ADIOLOGY 'l1.11 NCOLOGY September 1999 ol. 33 No. 3 Ljubljana ISSN 1318-2099 1 l ' '" ?.:. ( ADIOLOGY AND NCOLOGY cillTI. Editorial office Radiologij and OncologiJ Septe111ber 1999 Institute oj Oncology Vol. 33 No. 3 Vrazov trg 4 Pages 179-255 51-1000 Ljubljana lSSN 1318-2099 5/ovrnia UDC 616-006 P/wne: +386 61 1320 068 CODEN: RONCEM Pho11e/Fnx: +386 61 1337 410 E-111ail: gsersa«vonko-i.si Aims and scope Radiology and Oncology is a jounrnl devoted to pllb!ication of origi11al conlriblltions in diagnostic a11d i11tervenlio11al radiology, complllerized tonzogmplzy, ultrasozmd, magnelic resonance, 1111clenr medicine, radiotlzerapy, clinical and experi111ental oncology, radiobiology, rndiophysics and rndiation protection. Editor-in-Chief Editor-in-Chief Emeritus Gregor Serša Tomaž Benulic Ljllb/jana, Slovenia Ljllb/jana, 5/ovenia Executive Editor Editor Viljem Kovac Uroš Smrdel Ljubljana, Slovenia Ljubljana, Slovenia Editorial board Marija Auersperg Bela Fornet Maja Osmak Ljubljana, 5/ovenia Budapest, H1111gary Zagreb, Croatia Nada Bešenski Tullio Giraldi Branko Palcic Zagreb, Croatia Trieste, Italy Va11couve1; Canada Karl H. Bohuslavizki Andrija Hebrang Jurica Papa Hamburg, Germany Zagreb, Croalia Zagreb, Croatia Haris Boka Ltiszl6 Horvat/z Dušan Pavcnik Zagreb, Croatia Pecs, H1111gary Porlla11d, USA Nataša V. Budihna Berta Jereb Sto;an Plesnicar Ljubljana, 5/ovenia Ljllblja11a, Slovrnia Ljubljana, Slovenia Marjan Budi/zna Vladimir Jevtic Ervin B. Podgoršak Ljubljana, Slovenia Ljllb/jana, 5/ovenia Montreal, Canada Malte Clausen H. Dieter Kogelnik Jan C. Roos Hamburg, Ger111m1y Salzburg, Austria Amsterdam, Netherlands Clzristoph Clemm Jurij Lindtner Slavko Šimunic Miine/zen, Gennany Ljubljmw, Slovenia Zagreb. Croafia Mario Corsi Ivan Lovasic Lojze Smid Udine, Italy Rijeka, Croalia Lj11blja1.a,Slovenia Christian Dittrich Marijan Lovrencic Borut Stabuc Viemw, Austria Zagreb, Croatia Ljubljana, 5/ovenia Ivan Drinkovic Luka Milas Andrea Veronesi Zagreb, Croatia Houston, USA Aviazzo, Itali; Gillian Duchesne Metka Milcinski Živa Zupa.cic Melbourne, Australia Ljub/jazza, Slove11ia Lj11blja11a, 5/ovenia Publishers S/ovenian Medica/ Associatioll Sloveniall Association oj Radiology, Nuc/ear Medici11e Society, S/ove11ia11 Society far Radiotherapy alld Oncology, and Slovenian Cancer Society Croatian Medica/ Association Croatian Society oj Radiology Affiliated with Societas Radiologorunz Hungaroru111 Friuli-Venezia Giu/ia regional groups oj S.I.R.M. (Italian Society oj Medica/ Radiology) Copyright © Radiology a11d Oncology. Ali rights reserved. Reader for English Olga Shrestha Mojca Cakš Key words Eva Klemencic Secretaries Milica Harisch Betka Savski Design Monika Fink-Serša Printed by Imprint d.o.o., Ljublja11a, Slovenia Published quarterly i11 750 copies Bank accou11t 1111111ber 50101 679 901608 Foreigll currrncy acco1111t number 50100-620-133-900-2 7620-978-515266/ 6 NLB -Ljublja11ska banka d.d. -Ljubljana Subscription fee far i11stitutio11s $ 100 (16000 SIT), individuals $ 50 (5000 SIT) The publication oj this journal is subsidized by the Ministry oj Science and Technology oj 1/ze Republic oj S/ovenia. According to tl1e opinio11 oj the Govern111e11t oj the Republic oj Slovenia, Public Relation and Media Office. The journal Radiology and Oncology is a publicatio11 oj informative value, and as such subject to taxation by 5 % sa/es tax. lndexed and abstracted by: BIOMEDICINA SLOVENICA CHEMICAL ABSTRACTS EMBASE / Excerpta Medica This journal is printed on acid- free paper Radiology a11d 011cology is available on the internet at: http://www.o11ko-i.sijradiolog/rno.litm ADIOLOGY AND NCOLOGY Ljubljana September 1999 Vol. 33 No. 3 CONTENTS ULTRASOUND .TI. ISSN 1318-2099 UDC 616-006 CODEN: RONCEM Treatment of hyperfunctioning thyroid nodules with ultrasound guided percutaneous ethanol injection -30 months experience Brkijacic B, Sucic M, Božikov V, Hebrang A 179 Sonographic diagnosis of soft-tissue foreign bodies in children Raic G, Ercegovic S, Vlahovic T, Cop S, Bumci I, Višnjic S 189 Ultrasonographic diagnosis of obstructive ileus in a patient with Meckel' s diverticulum (case report) Alenka Višnar-Perovic A, Koren A 193 COMPUTERIZED TOMOGRAPHY When do heterogeneous splenic enhancement patterns occur in contrast­enhanced CT studies of the abdomen ? Groell R, Rienmiiller R, Uggowitzer MM, Kugler C, Stauber RE, Fickert P NUCLEAR MEDICINE Value of F-18-FDG PET in patients with cervical lymph node metastases of unknown origin Bohuslavizki KH, Klutmann S, Buchert R, Kroger S, Werner JA, Mester ], Clausen M Renal transplant blood flow in patients with acute tubular necrosis Huic D, Grošev D, Bubic-Filipi L, Crnkovic S, Dodig D, Poropat M, Puretic Z 215 EXPERIMENTAL ONCOLOGY Cryosurgery combined with radiotherapy of tumors in mice Fras AP, Kranjc S, Cemažar M, Serša G 221 RADIOPHYSICS A modified half-block breast irradiation technique using a CT-simulator Evans MDC, Benk V, Freeman C, Gosselin M, O/ivares M, Podgorsak EB Evaluation of silicon microstrip detectors as X-ray sensors in digital mammography Mali T, Cindro V, Mikuž M, Zdešar U, Jancar B 227 237 SLOVENIAN ABSTRACTS 245 NOTICES 253 Radio/ 011co/ 1999; 33(3): 179-87. Treatment of hyperfunctioning thyroid nodules with ultrasound guided percutaneous ethanol injection -30 months experience Boris Brkljacic"I, Mate Suck2, Veljko Božikov2, Andrija Hebrang1 1 Departrnent oj Radiology, University Hospital "Merkur" and 2 Department oj Interna/ Medicine, Division oj Endocrinology, University Hospital "Dubrava", Zagreb, Croatia Background. Our technique oj performing percutaneous ethanol injection (PEI) and results after 30 months are presented alld compared with results from the literature. Material and methods. PEI was pe1formed in 40 patients (37 Jemale, 3 male, age range 28-76 years); in 35 cases, there was a solitary, scintigraphically "Jzot" nodule, and in 5 cases a toxic nodular goiter was found. The volume of treated nodules was in the range from 2.5 to 38 ccm (mean vohune 20.7 ± 14.1 cC1n). Etha­nol was injected witlz the 'jree-hand" tec/mique, usually in multiple sessions, with the color and power Doppler ultrasound guidance. The tata/ injected vohnne oj ethanol was 1.5 times the vohune oj the treated 11odule. Results. The procedure was tec/mically successful in 37 patients (92.5%). Pain during injection was observed in ali cases, subcutaneous hematoma in 6 cases, and transitory dysphonia in one patient. There were no long-tenn complications. In 36 patients, the successfulness oj the treatment was evaluated after 3­ 4 months on the basis of scintigraphy, hormona/ status and ultrasonographic findings. A complete and par­tial cure was achieved in 22 (61.1 %) and in 10 patients (27.8%) of patients, respectively, whereas in 4 patients (11.1 %) the result was unsatisfactory, since only a moderate hormona/ remission was observed after the completion of the procedure. A satisfactory result was observed in 32/36 patients (88.9%). Significant reduction of nodular volume was noted in ali cases. A better result was observed in smaller nodules and in cases of autonornous adenomas. No cases of recurrent hyperthyreosis were detected. Conclusions. Percutaneous ethanol injection under ultrasound guidance is an efficient and saje method in the treatment oj autonomous thyroid nodules, that enables inactivation of nodules witlz minimal and/or transitory complications, without permanent ar serious complications that can be observed after radioiodine ar surgical therapy. Key words: thyroid nodule -drug therapy; ethanol; thyroid neoplasms -ultrasonography; autonomous adenoma Correspondence to: Doc. Boris Brkljacic, MD, PhD, Ultrasonic Center, Department of Radiology, University Hospital "Merkur", Zajceva 19, 10000 Zagreb, Croatia; Phone: 385 1 2431 413; Fax: 2431 397; E-mail: boris.brkljacic 0.05). In the patients with ATN, mean RBFjCOs were significantly related to creatinin serum (CS) value (CS < 500 µmolji -8.0 % ± 3.0 %, CS > 1000 µmolji -5.2 % ± 2.2 %, p < 0.05) and to 1-131 OIH renogram patterns (some OIH excretion from renal parenchyma during the examination -7.0 % ± 3.5 %, no excretion -5.1 % ± 2.2 %, p < 0.05). Conclusions. Rena/ transplant blood flow is clearly diminished in ATN, similarly as in AR, and signifi­cantly related to the graft function. Key words: kidney transplantation; kidney tubular necrosis, acute, kidney-blood supply-radionuclide imaging; quantitative analysis; graft rejection Received 12 April 1999 Accepted 24 April 1999 Correspondence to: Huic Dražen, MD, Clinical Department of Nuclear Medicine and Radiation Protection, University Hospital Rebro, Kišpaticeva 12, 10000 Zagreb, Croatia; Phone: ++385 1 23 33 850; Fax: ++385 1 23 35 785; E-mail: huic@mailexcite.com Introduction Radionuclide methods, as non-invasive pro­cedures, are very useful in detection of many complications, which affect renal transplants. It is necessary to study both renal perfusion and function to differentiate post-transplant complications. 1,2 Huic D el a/. / Rena/ lra11spln11I blood flow Acute tubular necrosis (ATN) is present in the majority of cadaveric transplanted kid­neys, but only infrequently in transplants from living related donors. It arises in the immediate post-transplant period and usually resolves without therapy. The major patho­logic changes in ATN are caused by ischemic damage to the kidney, which usually arises from prolonged ischemia caused by harvest­ing and implanting of the kidney or by reac­tion to X-ray contrast media. Rena! blood flow (RBF) in patients with ATN has been shown to be associated equal­ly with both good and compromised perfu­sion and it has been usually described as "rel­atively good", always assumed better than in acute rejection (AR).1-6 Since the data are contradictory, the aim of our study was to investigate the quantity of renal transplant blood flow in patients affect­ed by ATN. Subjects and methods Patients During the four year period, 179 examina­tions were performed in 60 patients (31 female, 29 male, median age 37 years, range 11-62 years). Forty-two patients received the kidney from cadavers and 18 from living related donors. Median follow-up was 21 months (range 1-45 months). A baseline examination with Tc-99m pertechnetate (per­fusion) and I-131-0IH (function) was per­formed in ali patients within 48 hours of transplantation and additional examinations during post-transplant period in the patients in whom the transplant function impairment was suspected. Ali patients were treated with antirejection therapy. Diagnostic criteria Ali examinations were classified by the fol­lowing diagnostic criteria: A. Acute tubular necrosis (ATN) l. Delayed and prolonged peak of the OIH renogram. 2. No sings and symptoms of rejection on the day of the examination and within the fol­lowing week. 3. Clinical and OIH renographic improve­ment after supportive therapy only. B. Acute rejection (AR) l. Signs and symptoms of AR (graft tender­ness, pyrexia, rising serum creatinine leve! or decrease in the creatinine clearance). 2. Evidence of rejection confirmed by biopsy (when available). 3. Clinical improvement after specific treat­ment for acute graft rejection. C. Acute tubular necrosis complicated with acute rejection (ATN+AR) l. Criteria A+B. D. Normal functioning graft l. Good urine production of at least 150 ml/h. 2. Serum creatinine leve! not more than 130 µmol/!. 3. No sings and symptoms of rejection on the day of the examination and within the fol­lowing week. 4. Normal appearance of OIH renogram. Radionuclide studies The perfusion and subsequent dynamic graft scintigraphy were performed using 555 MBq of Tc-99m-pertechnetate and 8 MBq of I-131­0IH. Tc-99m-pertechnetate was injected rapidly as a compact bolus. A gamma camera with low energy parallel collimator was used for l-Iuic D et al. / Rena/ trallsplalll b/ood flow data acquisition. Flow images were collected at a frame rate of 1 per sec for 60 sec. Pre-and post-dose syringe counts were measured on collimated gamma camera's face as 10 sec static frames for measuring the net injected dose. Dead tirne correction was per­formed as described previously.7 The distance between an anterior abdomi­nal wall marker and the center of the trans­planted kidney was obtained on a laterni view for depth correction factor measuring. The dynamic examination with I-131-OIH was performed immediately after perfusion study using medium energy collimator and a frame rate of 1 per minute for 20 minutes for data acquisition. Data analysis The well known method for measuring RBF as a percentage of cardiac output (CO) was applied on blood flow studies.s,9 One region of interest was placed around the kidney and three along the course of the abdominal aorta. Each aortic curve was corrected for recircula­tion using a gamma fit, integrated and multi­plied by the ratio of the maximum upslope of the integrated gamma function aortic curve. The obtained curve represents the renal curve that would be recorded if the Tc-99m-pertech­netate was totally trapped in the vascular bed of the kidney on the first pass. RBF as a fraction of CO was finally calcu­lated from the formula: gk x A x DCF x 100 RBF/CO ga xD where RBF/CO = RBF as a percentage of CO; gk = maximum upslope of the renal curve; ga maximum upslope of the integrated aortic curve; A = plateau of the integrated aortic curve (cts/sec); D = net injected dose (cts/sec); DCF = depth correction factor (eµx); m = Tc-99m soft tissue linear attenuation coefficient (0.153 cnr1 ). A fina! RBF/CO value was expressed as an average value of three estimates from three aortic ROis. Statistical analysis Comparative testing of more than two vari­ables at a tirne was performed by the Kruskal­Wallis analysis of variance. Differences were considered significant if the respective proba­bility values were less than O.OS. Testing of Kruskal-Wallis sub-groups was conducted by the Mann-Whitney-U test. The t -test was used for testing the differences between the two variables. A summary statistics, including mean val­ues, standard deviations, and minimal and maximal values was run on ali data sets. Results According to our diagnostic criteria 42 patients (33 cadaveric and 9 living related transplantations) were affected with ATN in the immediate post-transplant period. In 53 examinations of the patients with ATN, the mean RBF/CO value was signifi­cantly lower than in 60 examinations of the patients with normal graft function (6.5% ± 3.4%, 11.4% ± 3.4%, respectively; p = 9.6 x 10-12; Mann-Whitney-U test ), but similar to the mean RBF/CO values of 49 examinations of the patients with AR and 17 examinations of the patients with the combination of ATN and AR (7.3 % ± 3.4 %, 5.8 % ± 2.5 %, respec­tively; p > O.OS; Mann-Whitney-U test). These data are summarized in Table 1. In patients with ATN, mean RBF/CO val­ues were significantly related to the creati­nine serum (CS) leve! and to OIH renogram patterns, as shown by the first examinations after transplantation. The mean RBF/CO was 5.2 % ± 2.2 % in nine examinations with CS > 1000 µmol/! and 5.3 % ± 3.2 % in 20 examina­tions with CS between 501 and 1000 µmol/!, Huic D el al. / Rena/ transplant blood flow Table 1. Mean RBF/CO values, standard deviations and ranges in patients with normal graft function, ATN, AR, andATN+AR Diagnosis Mean RBF/CO (%) Standard deviation (%) Range(%) Number of examinations ATN 6.5 3.4 1.4 -19.2 53 AR 7.3 3.4 1.2 -16.1 49 ATN +AR 5.8 2.5 1.9 -13.2 17 Normal 11.4* 3.4 6.4 -21.1 60 * significantly different from ali other mean values (Kruskal-Wallis analysis of variance, p = 4.8 x 10-14). as a contrary to higher RBF/CO values in 13 99-pertechnetate is preferable for simple rou­examinations with CS less than 500 µmol/1 tine studies because of its low price, high vas­ (8.0 % ± 3.0 %; p = 0.044; Kruskal-Wallis cular transit and low kidney radiation.10 At analysis of variance; Table 2). the same tirne, we perform quantitative analy- Table 2. Mean RBF/CO values, standard deviations and ranges in patients with ATN according to creatinin serum values (CS) CS (µmol/!) Mean RBF/CO (%) Standard deviation (%) Range(%) Number of examinations < 500 8.0*0 3.0 5.6-14.3 501-1000 5.3* 3.2 1.5-12.2 20 > 1000 5.2° 2.2 1.4-8.5 9 * p = 0.034; 0 p = 0.025 (Mann-Whitney-U test) Some excretion of OIH from renal parenchyma during 22 I-131-OIH examina­tions was accompanied with better renal blood flow (RBF/CO = 7.0 % ± 3.5 %) in com­parison with 20 cases without any hippuran excretion (RBF/CO = 5.1 % ± 2.2 %; p < 0.05, t­test). In 13 patients affected with ATN graft function recovered and became normal in the second examination after transplantation. This improvement was followed with the mean RBF/CO rise of 5.4 % ± 3.4 % (range -0.2 % -13.6 %). Only one patient did not show any flow improvement (Table 3.). Discussion At our department, we routinely use Tc-99 pertechnetate for assessing renal transplant perfusion. Since the renal handling of Tc-99m-DTPA, Tc-99m-MAG3 and I-123-OIH interferes on the downslope of the first-pass curve, these pharmaceuticals may be less use­ful in poorly or non-functioning kidneys. Tc-sis of the transplant blood flow which is based on the principle of fractionation of car­diac output. This method depends minimally on bolus shape and is applicable with any recirculating gamma emitting tracer. 8,9,ll The major pathologic changes in ATN are caused by prolonged ischemia, which usually arises during harvesting and implanting of the kidney. ATN is present in the majority of cadaveric kidneys and, in most cases, it will resolve without therapy in few weeks follow­ing the transplantation. Histologically, there is dilatation of the proximal as well as O 80 ----4>-Control ::, -v-Cryo 1 min. E .... 50 ---6-Cryo 3 min. ----lili Cryo 5 min. 30 10 12 14 16 18 20 Time after treatment (days) l. The antitumor effect of cryosurgery on subcu­ Figure taneous fibrosarcoma SA-1 tumors in A/J mice. Cryosurgery was performed with 8 mm probe cooled by liquid nitrogen for 1, 3 and 5 minutes. Symbols, mean tumor volume; vertical bars, standard error of the mean. 500 300 ME E ::, 100 > 5 80 E ::, -o-Control 50 -.\-Cryo3min. --ill--RT 10 Gy -+-RT+Cryo 30 ---Cryo+ RT O 2 4 6 8 10 12 14 16 18 W 22 M 26 U W Time after treatment (days) Figure 2. The antitumor effect of cryosurgery combined with radiotherapy on SA-1 tumors in mice. Cryosurgery was performed for 3 minutes and radiotherapy by local tumor irradiation with 10 Gy. The interval between croy­surgery and radiotherapy was 5 minutes. Symbols, mean tumor volume; vertical bars, standard error of the mean. quence dependent. We faund that the tumor growth delay was prolonged when tumors were treated with irradation befare cryo­surgery. The inverse combined treatment did not differ significantly compared to irradia­tion alone. Cryosurgery is being increasingly consid­ered as a treatment of choice far a number of malignant skin tumors.1 Moreover, better Radio/ Onco/ 1999; 33(3): 221-5. understanding of the mechanisms of tissue injury by cryosurgery has lead its way into broader clinical practice far treatment of the head and neck and gyneacological tumors. It is known that tissue damage by freezing depends on both, freeze and thaw rates; in many instances, rapid freezing and slow thawing should be used.2 Injury is increased by repeating freeze-thaw cycles.3 The best results of cryosurgery have been obtained in the treatment of malignant skin lesions.1 The overall cure rates obtained by cryosurgery compare favourably with those obtained by other treatment modalities. The depth of freezing is approximately the same as the lateral spread of frost from the edge of the probe. However, when the volume of the tumor hampers the optimal freezing, cryosurgery can not be perfarmed adequately. These advanced bulky tumors may require combined therapeutic technique, such as combined cryosurgery and radiotherapy. It can be predicted that cryosurgery may deal better with central portion of the tumor, that tends to be radioresistant, while radiotherapy would deal better with the peripheral parts of the tumor that are more radiosensitive due to better oxygenation. However, there have been only limited studies of hypothermia dealing with response to subsequent irradiation, either to cells or tissues in vivo. s,s,9 Generally, enhanced radiosensitivity of cells and tumors after hypothermia have been observed, but the magnitude was dependent on cell line used, cooling temperature, duration, and rewarm­ing interval befare irradiation. In this study, the importance of sequencing was examined, i.e. local irradiation of tumors either befare or after cryosurgery. This is important, since the rationale of tumor irradiation after cryosur­gery bears the notion that cryosurgery may predispose cells to radiation damage. However, cryosurgery after irradiation can have the rationale in the potentiation of sub­lethal radiation damage of cells. Fras AP el ni. / Cryosurgery combined with radiotlzempy Although the aim of this study was not to investigate the underlying mechanisms of antitumor effectiveness of combined cryo­surgery and radiotherapy, the results show that in our experimental design, cryosurgery was more effective when given after radio­therapy. Acknowledgements This work was supported by the Ministry of Science and Technology of the Republic of Slovenia. References l. Gage A. Cryosurgery in the treatment of cancer. Surg Gy11eco/ Obstet 1992; 174: 73-92. 2. Gage AA, Baust J. Mechanisms of tissue injury in cryosurgery. Cryobiology 1998; 37: 171-86. 3. Gage AA, Guest K, Montes M, Caruana JA, Whalen Jr DA. Effect of varying freezing and thaw­ing rates in experimental cryosurgery. Cryobiology 1985; 22: 175-82. 4. Kuflik EG. Cryosurgery for cutaneous malignancy. Dernwtol Surg 1997; 23: 1081-7. 5. Shibata T, Yamashita T, Suzuki K, Takeichi N, Micallef M, Hosokawa M, Kobayashi H, Mura ta M, Arisue M. Enhancement of experimental pul­monary metastasis and inhibition of subcuta­neously transplanted tumor growth following cryosurgery. A11ticn11cer Res 1998; 18: 4443-8. 6. Zouboulis CC. Cryosurgery in dermatolos'Y-Eur J Dermatol 1998; 8: 466-74. 7. Bi.ichner SA. Kryochirurgie bei malignen Tumoren der Haut. Tlzernpe11tisclze Umsiinu 1993; 50: 848-51. 8. van Rijn J, van den Berg J, Kipp JBA, Schamhart DHJ, van Wijk R. Effect of hypothermia on celi kinetics and response to hyperthermia and X rays. Rndiat Res 1985; 101: 292-305. 9. Burton SA, Paljug WR, Kalnicki S, Werts ED. Hypothermia-enhanced human tumor cell radiosensitivity. Cryobiology 1997; 35: 70-8. 10. Vergnon JM, Schmitt T, Alamartine E, Barthelemy JM, Fournel P, Emont A. lnitial combined cryother­apy and irradiation for unresectable non-small celi Jung cancer. Clzest 1992; 102: 1436-1440. 11. Zogafos L, Uffer S, Bercher L, Gaillound C. Chirurgie, cryocoagulation et radiotherapie com­binee pour le traitement des melanomes de la con­juctive. Klin Mo11/asbl Auge11/zeilkd 1994; 204: 385­90. Radio/ Ollcol 1999; 33(3): 227-35. A modified half-block breast irradiation technique using a CT-simulator Michael D.C. Evans1 , Veronique Benk2, Carolyn Freeman2 Micheline Gosselin,1 Marina Olivares,1 Ervin B. Podgorsak1 1 Department oj Medica! Physics, 2Department oj Radiation Oncology, McGill University Health Centre, Monh·eal, QC, Canada Purpose. Over the past two decades numerous approaches with varying degrees oj complexity have been proposed far radiation treatment oj the breast and peripheral lymphatics. In our center a single isocente1; rotating halfblock technique has been used since 1982, and the recent installation of a CT-simulator and a linear accelerator with asymmetric jaws has provided an impetus to improve our treatment technique by incorporating this new technologiJ into the treatment planning and dose delivery process. Materials and methods. Our breast irradiation technique requires no couch ar patient motion when switching from one field to anothe1; and provides a smooth and reproducible junction between the tangen­tia/ chest wall fields and the supraclavicular fields. Before treatment, the patient is scanned on the CT-sim­ulator, and with the aid oj virtual simulation software the optimal isocenter, common to ali radiation fields, is determined and marked on the patient's skin. Results. Since 1997, 17 patients have been treated with the modified breast irradiation technique. The sim­ulation time is reduced to about 30 minutes. The patient setup on the Zinem· accelerator is straightforward, and the dose delivery is re/atively simple because all fields, despite being half-blocked, use the same isocen­ter. The wedged tangentia/ fields are produced with a dynamic wedge, and the asymmetric jaws enab/e us to determine the optimum isocenter common to ali treatment fields. Conclusions. Treatment planning far our breast irradiation technique is based on virtual simulation, and dose delivery is accomplished on a 6 MV linear accelerator incorporating a rotating half-block, asymmetric jaws, dynamic wedge, and a multileaf collimator. The technique is practical, meets the requirements far ade­quate irradiation of the breast and peripheral lymphatics, and is easy to implement on modern Zinem· acce/­erators. Key words: breast neoplasm-radiotherapy; radiotherapy dosage; rotating half-block, CT-simulation, beam matching Correspondence to: Michael D.C. Evans, M.Se., FCCPM, Department of Medica! Physics; McGill University Health Centre, 1650 Ave Cedar, Montreal, PQ, Canada H3G 1A4; Phone: +1514 934-8052; Fax: +1 Received 11 January 1999 Accepted 27 January 1999 514 934-8229; E-mail: mevans@medphys.mgh.mcgill. ca; Internet: http://www.medphys. mgh. mcgill. ca Eva11s MDC et ni./ Breast irrndiatio11 technique lntroduction Since 1982 our center has used a single isocenter breast irradiation technique for treatment of the breast or chest wall and draining lymphatics. The technique as origi­nally described,1, 2 uses a rotating half-block to achieve a match between the two tangen­tial chest wall fields and the AP-PA fields used to treat the axilla and supraclavicular region. A single isocenter is used for all four fields, and no couch motion is required when switching from one field to another. The acquisition in 1994 of a CT-simulator and a linear accelerator with asymmetric jaws provided an opportunity to improve the tech­nique in terms of treatment planning and beam delivery. In this paper we describe the modified technique, which uses virtual simu­lation software for the determination of the optimal location of the treatment isocenter and relies upon a rotating half-block and asymmetric jaws to define the treatment fields. It has been established that the isodose distributions and matchline dosimetry that were perfonned for the original technique1 have not changed for the modified technique, therefore this paper presents only the modifi­cation to the planning using the CT simulator. Materials and methods Numerous techniques with varying degrees of complexity have been proposed for radia­tion treatment of the breast and peripheral lymphatics.3-IO Our original technique was designed around the capabilities of linear accelerators without asymmetric jaws. The isocenter of the machine was placed onto the patient's skin on the matchline between the two treatment volumes and midway between the medial and lateral limits of the anterior supraclavicular field. While this isocenter position was appropriate for the supraclavic­ular region, it was not always optimal for the Radio/ Oncol 1999; 33(3): 227-35. two tangential chest wall fields, and often resulted in the isocenter for the two tangen­tial fields being located medially with respect to the position which would be chosen for a simple set of opposed tangential chest wall fields. In our current technique the most appro­priate isocenter is chosen for the tangential fields first, and then this isocenter is also used for the supraclavicular fields in conjunc­tion with asymmetric jaws. Both our original and current breast techniques are shown schematically in Figure 1. For the original technique the solid dot (point 1 in Figure la) indicates the position of the treatment isocen­ter at the matchline of the fields, positioned midway between the medial and lateral limits of the supraclavicular field. The analogous isocenter point in our current technique (point 2 in Figure lb) is shown shifted lateral­ly. The placement of the isocenter using the symmetric jaws (point 1) was on the patient's skin, while typically point 2 will be posi­tioned subcutaneously. The line CC' runs through point 2 along the coronal aspect of the patient. Two transverse sections through the patient are shown for the original technique (Figure le) and the modified technique (Figure ld). As indicated in Figures la and lb, section A.A: is at the level of the beam match­plane and section BB' is at a leve! midway through the tangential chest-wall volume. The constraints imposed by the linac with sym­metric jaws required that the treatment isocenter (point 1) be placed medially, forcing the apparent isocenter (point 1') of the tan­gential fields to be off mid-volume and requir­ing unequal beam weights to produce an opti­mized 5 is some­what lower, which is due to the source inten­sity variations in tirne. Since the image is obtained by scanning, the instability of cur­rent in the X-ray source is manifested as the background variation along the x axis. The low exposure rate (3.3 ± 0.3 mGy/min) result- Mali Te/ ni./ Silico11 de/ectors i11 digitnl mnmmogmplzy O 1 2 3 4 5 6 7 8 9 1 O x [mm] Figure 3. Microcalcifications with a diarneter of 350 .Lrn. The contrast of the object at x=3.5 is 6%. The image was obtained by scanning in x direction with a scanning step of 200 µrn; the strip pitch of the detector was 100 µm. The size of pixels is 300x100 .lrn2 (x x 1/ size). The irnage was obtained at a skin entrance 3 mGy). It is Mali T el ni./ Silicon deleclors in digitnl 111n111111ogrnp!t11 y[mm] M -----------------------­ 1.4E ___ \i/ ".,.''f 1.2 1 0.8 0.6 0.4 0.2 0.2 0.4 0.6 0.8 1.2 1.4 1.6 1.8 2 x[mm] o 0.2 0.4 0.6 0.8 1.2 1.4 1.6 1.8 2 x[mm] Figure 5. The 5 lp/mm detail from the phantom (Fig. 5a). Due to relatively large, finite size of pixel in x direction (300 ftm), the image is distorted. lnstead of five lines, separated by 200 µm, there are four lines separated by 200 µm, super -­ imposed on a plateau (see text below). A x direction cut of Figure 5a at y = 0.5 mm is shown in Figure 5b. expected that the contrast of the images improves, when softer spectum is used9, how-­ever at the moment such source is not avail-­able to our group. As our results show, the high efficiency of microstrip detectors can reduce the required dose per investigation. However, when com­pared to the screen-film, their drawback is a lower spatial resolution. We demonstrated, that 5 lp/mm details (in x direction) can be detected if an appropriate scanning step is chosen. However, due to the large size of pix­els, the signal is distorted (Figure 5). There are stil! four main improvements which may be implemented. First, a wider and stacked detection system should be assembled in order to reduce imaging time. Stacking 4 to 6 layers of wider detectors would result in a detector covering the area of approx. 1 mmx5 cm. This would enable imag­ing of larger objects as well as a reduction of scanning time. Next, detectors with a lower cutting dis­tance could be used in order to improve effi­ciency. There are indications that a safe cut­ting distance could be below 200 µrn, result­ing in detector efficiency above 80% at 20 keV. In comparison, the efficiency of the described detector was about 55%. The pixel size could be reduced by using thinner silicon substrates (e. g. 200 µm) and a finer strip pitch (e. g. 50 µrn) leading to a bet­ter spatial resolution. Finally, the transfer function of the system must be carefully evaluated and this informa­tion used for digital image processing, thus reducing the leve! of distortion due to the finite pixel size. With the irnplernentation of all these improvements, the dose required for mam- Mali Tet ni./ Silicon detectors in digital 111am111ograplzy mography may be reduced for a factor of about five compared to standard screen film. References l. Arfelli F, Barbiellini G, Cantatore G, Castelli E, Cristaudo P, Dalla Palma L et al. Silicon X-ray detector for synchrotron radiation digital radiolo­gy. Nucl lnstrum Meth A 1994; 353: 366-70. 2. Arfelli F, Barbiellini G, Cantatore G, Castelli E, Cristaudo P, Dalla Palma L et al. Silicon detectors for digital radiography. Nucl Instrum Meth A 1995; 367: 48-53. 3. Beuville E, Cederstriim B, Danielsson M, Luo L, Nygren D, Oltman E et al. High resolution X-ray imaging using a silicon strip detector. IEEE T Nucl Sci 1998; 45: 3059-63. 4. Mali T, Cindro V, Mikuž M, Richter R. Effect of cutting distance on noise of silicon microstrip detectors. Proceedi11gs of MIDEM 98 co11fere11ce, Rogaška Slatina, Slovenia,1998: 199-204. 5. Comes G, Loddo F, Hu Y, Kaplan J, Ly F, Turchetta R. CASTOR a VLSI CMOS mixed analog-digital circuit for low noise multichannel counting appli­cations, Nucl Instrum Me/11 A 1996; 377: 440-5. 6. Colledani C, Comes G, Dulinski W, Hu Y, Loddo F, Turchetta R et al. CASTOR 1.0: A VLSI CMOS mixed analog-digital circuit for pixel imaging applications. Nucl Instrum Met/z A 1997; 395: 435­42. 7. Mali T. Postavitev sistema za rentgensko slikanje z mikropasovnimi silicijevimi detektorji. [Diplom­sko delo], Ljubljana, Univerza v Ljubljani, 1997 8. Mali T, Cindro V, Mikuž M. X-ray imaging with a silicon microstrip detector. Proceedings of MIDEM 97 conference, Gozd Martuljek, Slovenia,1997: 347 -52. 9. Dance DR. Diagnostic radiology with X-rays. In: Webb S, editor. The physics of medica! imaging. Bristol and Philadelphia: Institute of Physics Publishing; 1988. p. 20-73. 10. Teuber J. Digital Image Processing. London: Prentice Hall; 1993. 11. Zavod RS za varstvo pri delu. Sevalna obremen­jenost prebivalstva zaradi medicinske upmabe ion­izirajocega sevanja v Republiki Sloveniji, porocilo za leto 1996. Ljubljana, 1997. S/ove11ian abstrnct Radio/ 011co/ 1999; 33(3): 179-87. Zdravljenje hiperfunkcijskih šcitnicnih nodusov z ultrazvocno vodenim perkutanim vbrizgavanjem etanola -30-mesecne izkušnje Brkljacic B, Sucic M, Božikov V, Hebrang A Izhodišca. V clanku predstavljamo svojo tehniko perkutanega vbrizgavanja etanola in rezultate po 30 mesecih zdravljenja ter jih primerjamo z rezultati, objavljenimi v literaturi. Bolniki in metode. Metodo perkutanega vbrizgavanja etanola smo uporabili na 40 bolnikih (37 žensk, 3 moški, starost od 28 do 76 let); od teh je bil pri 35 bolnikih ugotovljen solitaren in scinti­grafsko 'vroc' nodus, pri 5 pa toksicna nodularna golšavost. Volumen zdravljenih nodusov je znašal od 2,5 do 38 ccm (povprecni volumen 20,7 ± 14,1 ccm). Etanol smo vbrizgavali s prosto roko, ultrazvocno vodeno z barvnim in energijskim Doplerjem, obicajno v vec ponovljenih postopkih. Celoten volumen vbrizganega etanola je bil 1,5-krat vecji od volumna zdravljenega nodusa. Razultati. Postopek je bil tehnicno uspešen pri 37 bolnikih (92,5%). Vsi bolniki so tožili zaradi bolecine med vbrizgavanjem, podkožni hematom je nastal pri 6 bolnikih, prehodna disfonija pa pri 1 bolniku. Daljnorocnih zapletov zdravljenja ni bilo. Pri 36 bolnikih smo 3 do 4 mesece po zdravljenju ocenili uspešnost zdravljenja s scintigrafijo, s hormonskim stanjem ter z ultrazvocno preiskavo. Ozdravljenih je bilo 22 bolnikov (61,1 %), delno ozdravljenih pa 10 bolnikov (27,8 %). Pri 4 bolnikih (11,1 %) so bili rezultati zdravljenja nezadovoljivi, ker je bila po zdravljenju ugo­tovljena le skromna hormonska remisija. Zadovoljivi rezultati zdravljenja so bili doseženi pri 32/36 bolnikih (88,9 %). V vseh primerih pa se je volumen nodusa mocno zmanjšal. Boljše rezul­tate zdravljena smo ugotovili pri manjših vozlih in avtonomnih adenomih. Hipertireoza se ni ponovila pri nobenem bolniku. Zakljucki. Ultrazvocno vodeno perkutano vbrizgavanje etanola je ucinkovita in varna metoda zdravljenja avtonomnih šcitnicnih nodusov, ki preprecuje hiperaktivnost nodusov z minimalni­mi zapleti zdravljenja. Ti so prehodnega znacaja in niso resni, kot jih lahko opazimo po zdra­vljenju z radioaktivnim jodom ali po operaciji. Slove11ia11 abstrnct Radio] 011co/ 1999; 33(3): 189-92. Ultrazvocno diagnosticiranje tujkov v mehkih tkivih pri otrocih Roic G, Ercegovic S, Vlahovic T, Cop S, Bumci I, Višnjic S Izhodišca. Želeli smo ugotoviti uspešnost ultrazvocne metode pri diagnosticiranju tujkov mehkega tkiva. Bolniki in metode. Analizirali smo ugotovitve ultrazvoka pri 14 otrocih s tujkom v strukturah mehkega tkiva. Predhoden klinicni potek je bil pri bolnikih razlicen. Pri 6 bolnikih z rentgensko preiskavo niso našli tujka v telesu in sta bili identifikacija in odstranitev tujka neuspešni. Pri 5 bolnikih z manjšo površinsko prebodno rano sta po nekaj tednih do nekaj mesecih nastopili bolecina in oteklina struktur mehkega tkiva, rentgenski izvid pa je bil pravtako negativen. Pri 2 otrocih je nastal tujkov granulom, ko je bil tujek v mehkem tkivu že nekaj mesecev. Posumili smo na solidni tumor mehkega tkiva. Samo pri 1 bolniku je bil tujek (steklo) viden z rentgensko preiskavo, ni pa bilo mogoce dolociti njegovega položaja in globine. Rezultati. S pomocjo ultrazvoka smo natacno lokalizirali in oznacili položaj tujka v mehkih tkivih neposredno pred kirurškim posegom. Operacijo smo uspešno opravili pri vseh pregledanih bol­nikih, le pri bolniku z vec tujki je bilo potrebno kirurški poseg ponoviti, da bi odstranili preostale tujke. Zakjucki. Z ultrazvokom lahko uspešno dokažemo prisotnost tujka v mehkih tkivih, pa tudi okolišno granulaomatozno vnetno reakcijo. Radio/ Oncol 1999; 33(3): 193-98. Ultrazvocna diagnostika obstruktivnega ileusa pri bolniku z Meckelovim divertiklom Višnar-Perovic A in Koren A Uvod. Kljub uporabi modernih slikovnih tehnik, zanesljiva preoperativna ocena Meckelovega divertikla in z njim povezanih komplikacij te redke prirojene anomalije prebavnega trakta mno­gokrat ni mogoca. Predstavitev. Predstavljmo primer 25 letnega moškega, pri katerem se je pojavila nenadna boleci­na v spodnjem abdomnu desno. Klinicno je bil predel obcutljiv na palpacijo, ki je pokazala elasticno, valjasto strukturo globoko v trebuhu. Blumbergov znak je bil pozitiven, laboratorijske vrednosti pa v mejah normale. Ultrazvok abdomna je ileocekalno pokazal tekocinsko kolekcijo z gosto vsebino, sumljivo za Meckelov divertikel ali duplikacijsko cisto in ileus ozkega crevesa proksimalno od opisane strukture. Nativni rentgenogram stoje je potrdil prisotnost obstrukcij­skega ileusa v distalnem delu ozkega crevesa. Kirurški poseg je odkril ileus in kompresijo distal­nega dela ozkega crevesa zaradi prisotnosti edematoznega Meckelovega divertikla. Zakljucek. Glede na pogosto uporabo ultrazvoka pri oceni akutnega abdomna, bi lahko racional­izirali diagnosticni postopek in skrajšali cas do kirurške intervencije, ce bi možne zaplete Meckelovega divertikla upoštevali v diferencialni diagnozi. Radio/ Oncol 1999; 33(3): 245-52. Slove11ia11 a/,s/rac/ Radio! Oncol 1999; 33(3): 199-205. Kdaj se pri slikanju trebušne votline s kontrastom pri racunalniški tomografiji ojacijo heterogeni vzorci v vranici? Groell R, Rienmiiller R, Uggowitzer MM, Kugler C, Stauber RE, Fickert P Izhodišca. V študiji smo ugotavljali, kdaj se pri racunalniški tomografiji trebušne votline s kon­trastom pri bolnikih z diagnosticno potrjeno cirozo jeter in pri osebah brez takšne diagnoze ojacijo heterogeni vzorci v vranici. Bolniki in metode. Racunalniško tomografijo trebušne votline z elektronskim snopom smo izvedli po vbrizganem kontrastu pri 195 bolnikih. Vbrizgavanja kontrastnega sredstva smo opravili v skladu s tremi protokoli: protokol 1 (n=132, 120 ml, 2 m]/sek, slikanje po 50 sek), pro­tokol 2 (n=30, 90 ml, 3 ml/sek, slikanje po 10 sek) in protokol 3 (n=33, 50 ml, 5 ml/sek, slikanje po 10 sek). Od teh bolnikov jih je 34 imelo cirozo jeter. Rezultati. Ojacenje heterogenih vzorcev v vranici srno opazili pri 77'ľ., bolnikov (protokol 2) in pri 65% bolnikov (protokol 3) z zdravimi jetri, ter pri 23% (protokol 2) in 20% (protokol 3) bolnikov s cirozo jeter. Ojacani heterogeni vzorci so postali vidni med 14 in 48 sek po vbrizganju kon­trasta. Pri nobeni od skupin bolnikov in ob nobenem protokolu se ojacenje ni pojavilo kasneje kot v 48 sek po vbrizgu kontrastnega sredstva. Pri treh bolnikih smo odkrili lezije v vranici (hemangiom, limfam, metatstaze), ki so ostale vidne tudi 50 sek po vbrizgu kontrasta. Zakljucki. Iz rezultatov je razvidno, da ojacenje heterogenih vzorcev nastopi v casu 50 sek po zacetku vbrizgavanja kontrastnega sredstva. V enakem casu nastopi ojacenje heterogenih vzorcev tudi v primerih ko kontrast še vbrizgavamo. Slove11im1 abstmct Radio/ Oncol 1999; 33(3): 207-13. Pomen priskave s F-18-FDG PET pri bolnikih z metastazami v vratnih bezgavkah neznanega izvora Bohuslavizki KH, Klutmann S, Buchert R, Kroger S, Werner JA, Mester J, Clausen M Izhodišca. Ceprav imamo danes vec možnosti slikovne diagnostike, predstavlja metastaze nez­nanega izvora še vedno velik diagnosticen problem. Zato je bil namen naše studije opredeliti pri teh bolnikih pomen preiskave s fluor-18-fluorodeoksiglukozo (F-18-FDG) in pozitronsko emisij­sko tomografijo (PET) Material in metode. Obravnavali smo 28 bolnikov, starih od 39 do 84 let, od katerih jih je imelo 24 v vratnih bezgavkah metastaze skvamoznocelicnega karcinoma, 4 pa metastaze nediferenci­ranega karcinoma. Pri vseh bolnikih smo naredili klinicni pregled, ultrazvocno preiskavo vratu in CT glave. Ker nismo uspeli odkriti primarnega tumorja, smo se odlocili za preiskavo s PET. Vsem bolnikom smo intravenozno aplicirali 370 MBq F-18-FDG, po 60. minutah pa smo naredili tomografski posnetek celega telesa z aparatom ECAT EXACT 47 (921) (Siemens, CTI). Lezije, ki smo jih odkrili s PET-om, smo skušali pri vseh bolnikih oceniti tudi histološko ali s CT/MRI. Rezultati. Pri 16 od 28 bolnikih je PET pokazal žarišca kopicenja radiofarmaka, ki so ustrezala potencialnim primarnim ležišcem tumorja; pri 7 bolnikih v pljucih, pri 5 v tonzilah, po 1 bolnik pa je imel takšno žarišce v submandibularni žlezi, v nazofarinksu, v larinksu in v bazi jezika. Primarni tumor smo uspeli potrditi pri 9 od omenjenih 16 bolnikih; od tega 5 v pljucih, po enega pa v tonzili, v nazofarinksu, larinksu in v bazi jezika. Tako je pri 6 od 16 bolnikih preiskava dala lažno pozitiven rezultat, najveckrat v tonzilah, to je pri 3 bolnikih, en bolnik pa je odklonil nadaljnjo evaluacijo, s katero bi potrdili ali ovrgli rezultat preizkave s PET. Pri preostalih 12 od 28 bolnikih priskava PET ni pokazala za primarni tumor sumljivih lezij. Zakljucki. S preiskavo F-18-FDG PET lahko primarni tumor odkrijemo približno pri tretjini bol­nikov z metastazami na vratu neznanega izvora (CUP-sindrom), zato lahko omenjeno preiskavo pri teh bolnikih smatramo za pomembno pomoc pri izbiri ustreznega zdravljenja. Slovc11im1 nbslrac/ Radio/ Oncol 1999; 33(3): 215-20. Krvni obtok v ledvicnih transplantatih pri bolnikih z akutno tubularno nekrozo Huic D, Grošev D, Bubic-Filipi L, Crnkovic S, Dodig D, Poropat M, Puretic Z Izhodišca. Zaradi nasprotujocih se podatkov smo so odlocili za raziskavo ledvicnega krvnega obtoka (RBF) v ledvicnih transplantatih pri bolnikih z akutno tubularno nekrozo (ATN). Bolniki in metode. V štirih letih smo opravili 179 preiskav s Tc-99m pertehnetatom in I-131-OIH na 60 bolnikih (od teh je bilo 31 žensk in 29 moških, njihova srednja starost je bila 37 let in sicer od 11 do 62 let, presajenih je bilo 42 kadavrskih ledvic in 18 ledvic od živih darovalcev sorod­nikov, kontrolno sledenje je v povrecju trajalo 21 mesecev). Krvni obtok smo izracunali iz casovnih krivulj prvega pretoka skozi ledvice in aorto in ga izrazili v odstotkih iztisnega volum­na krvi iz srca (RBF/CO). Rezultati. V 53 preiskavah bolnikov z ATN je bil povprecni RBF/CO precej nižji kot pri 60 bol­nikih z normalnim delovanjem transplantirane ledvice (6,5 % ± 3,4 %; 11,4 % ± 3,4 %; p=9,6 x 10-12) in enak srednjim vrednostim 49 preiskav bolnikov z akutnim zavracanjem transplantirane ledvice ter prav tako enak 17 preiskavam bolnikov z ATN in z akutnim zavracanjem transplanti­rane ledvice (7,3 % ± 3,4 %; 5,8 % ± 2,5 %; p=0,005). Pri bolnikih z ATN so bile vrednosti RBF/CO v sorazmerju z vrednostjo serumskega kreatinina (KS<500 mmol/1 -8,0 % ± 3,0 %; KS >1000 mmoljl -5,2 % ± 2,2 %; p< 0,05) in z renogrami z I-131 OIH (delno izlocanje OIH iz ledvicnega parenhima med preiskavo -7,0 % ± 3,5 %; brez izlocanja -5,1 % ± 2,2 %; p=<0,005. Zakljucek. Krvni obtok v transplantiranih ledbicah se ocitno znatno zmanjša tako pri ATN kot pri akutnem zavracanju in je znacilno odvisen od delovanja transplatirane ledvice. S/ovenin11 nl>stract Radio/ 011col 1999; 33(3): 221-5. Kriokirurgija mišjih tumorjev SA-1 v kombinaciji z obsevanjem Fras AP, Kranjc S, Cemažar M, Serša G Namen naše raziskave je bil dolociti protitumorsko delovanje kriokirurgije kot samostojne tera­pije in v kombinaciji z obsevanjem. Kriokirurgija podkožnih fibrosarkomskih tumorjev SA-1, ki smo jih nasadili v A/J miši, je bila ucinkovita terapija. Zaostanek v rasti tumorjev po 5 minutnem zamrzovanju s tekocim dušikom je bil 10.3 ± 3.8 dni. Casovno krajše zamrzovanje je bilo manj ucinkovito, a odvisno od casa zamrzovanja. Pri kombinirani terapiji smo tumorje najprej zamr­zovali 3 minute in jih po 5 minutah obsevali z 10 Gy, oziroma najprej obsevali in jih po 5 minu­tah zamrzovali. Protitumorsko delovanje je bilo odvisno od vrstnega reda kombinirane terapije, tumorji ki smo jih obsevali pred zamrzovanjem so rastli pocasneje, kot tisti, ki smo jih obsevali po zmrzovanju. Kljub temu, da nekatere študije porocajo o povecani obcutljivosti celic na obse­vanje po kriokirurgiji, so naši rezultati pokazali, da te obcutljivosti na sevanje in vivo ne moremo vedno pricakovati, ter da so v protitumorsko delovanje kombinirane terapije verjetno vpleteni tudi drugi mehanizmi, ki prispevajo k poškodbam zaradi obsevanja, ce le-temu sledi kriokirurgi­ja. Slovrnim1 abslrncl Radio/ Onco/ 1999; 33(3): 227-35. Obsevanje dojke s prilagojeno tehniko polovicnega zapiranja polja in z uporabo CT simulatorja Evans MDC, Benk V, Freeman C, Gosselin M, Olivares M, Podgorsak EB Izhodišca. Zadnji dve desetletji so številni avtorji predlagali vrsto razlicnih nacinov obsevanja dojk in regionalnih bezgavk. V naši ustanovi od leta 1982 uporabljamo izocentricno tehniko s polovicnim zapiranjem polja; novejša uporaba CT simulatorja in linearnega pospeševalnika z asimetricnimi celjustmi sekundarnega kolimatorja pa je spodbudila prizadevanja za izboljšanje tehnike obsevanja z vkljucitvijo nove tehnologije v nacrtovanje obsevanja in v samo izvedbo obsevanja. Material in metode. Naša tehnika obsevanja ne zahteva premikanja obsevalne mize ali pre­mikanje bolnika pri obsevanju dveh zaporednih polj. Omogoca natancno in ponovljivo združevanje tangencialnega polja na prsni steni in supraklavikularnega polja. Pred obsevanjem bolnico slikamo na CT simulatorju, s pomocjo programa za virtualno simulacijo pa dolocimo in narišemo na kožo bolnice optimalni izocenter, ki je skupen vsem obsevalnim poljem. Rezultati. Od leta 1997 smo s prilagojeno tehniko obsevali dojke pri 17 bolnicah. Cas dela na simulatorju smo zmanjšali na 30 minut. Namestitev bolnice na obsevalno mizo linearnega pospeševalnika je bila enostavna, prav tako je bila enostavna, kljub polovicnemu zapiranju polj, izvedba obsevanja, saj so imela vsa polja isti izocenter. Oblikovanje polj smo izvedli z dinamic­nimi klini, uporaba asimetricnih celjusti na sekundarnem kolimatorju pa je omogocila optimalen izocenter, ki je bil skupen vsem obsevalnim poljem. Zakljucki. Nacrtovanje obsevanja z opisano tehniko temelji na virtualni simulaciji, obsevanje pa omogoca 6 MV linearni pospeševalnik, ki je izpopolnjen z rotacijskim sistemom polovicnega zapiranja polj, z asimetricnimi celjustmi na sekundarnem kolimatorju, z dinamicnimi klini in z veclistnim kolimatorjem. Takšna tehnika obsevanja je zelo uporabna, omogoca natancno obse­ vanje dojke in regionalnih bezgavk pri isti bolnici, prilagoditev sodobnega linearnega pospeševalnika pa ni težavna. Slove11in11 nbstract Radio/ Oncol 1999; 33(3): 237-44. Ovrednotenje silicijevih mikropasovnih detektorjev kot rentgenskih senzorjev za digitalno mamografijo Mali T, Cindro V, Mikuž M, Zdešar U, Jancar B Izhodišce. Pozicijsko obcutljive silicijeve detektorje smo uporabili kot senzorje rentgenskih žarkov v sistemu za digitalno rentgensko slikanje. Silicijevi detektorje smo uporabili v t. i. geometriji "na rob", kjer rentgenski žarki zadenjejo detektor s strani, zato lahko dosežemo visok izkoristek detekcije -preko 80% pri energiji rentgenskih fotonov 20 keV. Material in metode. Sestavili in testirali smo majhen sistem. Posneli smo slike standardnega, 5 cm debelega fantoma in jih ovrednotili. Rezultati in zakljucki. Silicijevi detektorji lahko znatno prispevajo k zmanjšanju doze pri mamo­grafskih preiskavah. Vse slike so bile posnete pri vstopni kožni dozi do 1 mGy. Mikrokalcifi­kacije s premerom 350 µm so še vedno vidne z vstopno kožno dozo 0.25 mGy. Pokazali smo, da z našim sistemom uspešno zaznamo testni vzorec crt z gostoto 5 parov na mm. Z nadaljno digi­talno obdelavo lahko še dodatno izboljšamo kvaliteto slik. Radio/ 011ca/ 1999; 33(3): 253-5. Notices Notices submitted for pu/Jlication should contain a 1nailing address, pl1011e and/or fax: JJumber nnd/or e-mail oj a Contact person or depnrtmeJJt. Immunotherapy of cancer September 20-23, 7999 The ESO training coursc will take place in Moscow, Russia. Contact ESO Office for Russia and Community of lndependent States, Blokhin Cancer Research Centre, L. Demidov, Kashirskoye shosse 24, 115478 Moscow, Russia; or call +70 95 3241184/3241504; or fax +70 95 324'1504 Gynecological oncology September 23-24, 1999 Thc ESO course on the occasion of the "7th Bicnnial Mecting of thc [nternational Gynecological Cm1cer Society" will take place in Rome, ltaly. Contact Triumph P.R. s.r.l., Via ['roba Petronia 3, 00136 Rome, ltaly; or fox +39 0639735195; or e-mail triumph(altin.it Gynecological oncology September 26-30, 1999 "7th The Biennial Meeting of the Intcrnational Gynecological Cancer Society" will bc offercd in Rome, ltaly. Contact Triumph P.R. s.r.l., Via Proba Petronia 3, 00136 Rome, ltaly; or fox +39 0639735'195; or c-mail triumph(al[in.it Radiation oncology September 26-30, 1999 ESTRO course on Evidence Based Radiation Oncology will be held in Bratislava, Slovakia. As a service to our rcaders, notices of meetings or courscs will be insertcd frce of charge. Please sent information to the Editorial office, Radiology and Oncolo6,y, Vrazov trg 4, 1000 Ljubljana, Slovenia. Contact ESTRO officc, Av. E. Mounicrlaan, 83/4, B­1200 Brussels, Belgium; or call +32 7759340; or fax +32 2 7795494; or e-mail info.Dcstro.be; web: http://­ WW\\'.estro.be Breast cancer Sepll'mber-Octobe,; 1999 Thc ESO training course will take place in Skopje, Macedonia. Contact ESO office for Balkans and Middlc East, N. Pavlidis, E. Andrcopoulou Medica! School, Depart­ment of Medica! Oncolo6>y, University 1-lospital of Joannina, 45110 loannina, Greece; or call +30 651 99394 or +30 953 91083; or fax +30 651 97505 Surgical oncology October, 1999 The ESO training course "Conservative Surgery and Combined Treatment" will take place in Sofia. Contact ESO office for Balkans and Middle East, N. Pavlidis, E. Andreopoulou Medica! School, Depart­ment of Medica! Oncology, Univcrsity Hospital of loannina, 45110 loannina, Greecc; or call +30 651 99394 or +30 953 91083; or fax +30 651 97505 Head and neck October 1-2, 1999 Th c first lnternational Chicago Symposium on Malignancies of thc Chest and I-Iead/Ncck will take place in Chicago, IL, USA. Contact Center for Continuing Medica! Education, Chicago University, 950 East 61st Strcct, Chicago, IL 60637, USA; or call +1 773 402 1056; or fax: +1 773 702 1736; or e-mail marlen«,,delphi.bsd.uchicago.edu Radiation oncology and biology Octobcr 4-6, 1999 Radiation Oncology and Biology Conference will be held on Bali, Indonesia. 254 Notices Contact ISRO secrctariat, Av. E. Mounier 83/12, "1200, Brussels, Belgium; or call +32 2 7759342; or fax +32 2 7795494; e-mail ISRO(a>estro.be Organ sparing treatment in oncology October 6-8, 1999 The ESO training course will take p[ace in Bled, Slovenia. Contact ESO officc for Central and Eastern Europe, Ms. Dagmar Just, Arztekammer fii Wien, Fortbildung­sreferat, Wcihburggasse 10-12, 41h floor, 1010 Vienna, Austria; or call +43 1 51501262; or fax +43 1 5150.1200; or e-n1ail just(tin.it Leukaemia lymphoma October 76-20, 1999 The ESO training course "Athens Postgraduate leukaemia lymphoma" will take place in Athens, Greece. Contact ESO office for Balkans and Middle East, N. Pavlidis, E. Andreopoulou Medica] School, Depart­ment of Medica! Oncology, University 1-lospital of loannina, 451]() loannina, Greecc; or call +30 651 99394 or +30 953 91083; or fax +30 651 97505 Radiobiology October 17-21, 1999 ESTRO course on Basic Clinical Radiobiology will be offered in Gdansk, Poland. Contact ESTRO office, Av. E. Mounierlaan, 83/4, B­1200 Brussels, Bclgium; or call +32 7759340; or fax +32 2 7795494; or e-mail infocu>estro.be; web: http://www.estro.be Melanoma Octo!Jer 25-26, 1999 The ESO training course will take place in Milan, ltaly. Notices 255 Contact ESO Office, Viale Beatrice d'Este 37, 2(Yl22 Milan, ltaly; or call +39 02583'1 7850; or fax +39 025832.1266: or e-mail csomi(u1tin.il Ovarian cancer Octo/1cr 25-27, 1999 The ESO training course "Ovarian Cancer and Trophoblastic Diseasc" will take placc in Moscow, Russia. Contact ESO Office for Russia and Community of lndependent States, Blokhin Cancer Research Centre, L. Demidov, Kashirskoye shosse 24, "115478 Moscow, Russia; or call +70 95 324"1"184/324.1504; or fax +70 95 3241504 Radiation therapy Oclobcr 31-November 3, 1999 ASTRO /\nnual meeting will be hcld in San Antonio, TX, US!\. Contact /\merican Society for Therapeutic Radiology and Oncology Office, 189'1 Prest(m White Drive, Reston, VA 20191, US/\. Skin cancer and melanoma Noue11i/1C1; "/999 The ESO training course will take place in Tirana, /\lbania. Contact ESO office for Balkan s and Middle East, N. Pavlidis, E. Andreopoulou Medica! School, Department of Medica! Oncology, University 1-lospital of loannina, 45UO loannina, Greece; or call +30 65"1 99394 or +30 953 91083; or fax +30 651 97505 Geriatric oncology November 3, "/999 The ESO training course will take placc in Tei /\viv, Israel. Contact ESO office for Balkans and Middle East, N. Pavlidis, E. Andreopoulou Medica! School, Department of Medica! Oncology, University 1-Iospital of loannina, 45]10 Ioannina, Greece; or call +30 65'1 99394 or +30 953 91083; or fax +30 651 97505 Antiangiogcnic thcrapy November 8-W, 1999 The ESO conferencc "13iological Basis for /\ntiangiogenic Therapy" will take place in Milan, ltaly. Contact ESO Office, Viale Bcatrice d'Este 37, 2(YI 22 Milan, Italy; or call +39 02583.17850; or fax +39 025832'1266: or e-mail esomi«"tin.it Sentinel nodc November 25-26, "1999 The ESO training course will be offered in Milan, ltaly. Contact ESO Office, Viale Beatrice d'Este 37, 20122 Milan, ltaly; or call +39 0258317850; or fax +39 0258321266: or e-mail csomi(<0tin.it Breast cancer Nm>c111ber 26-27, 1999 The ESO training course will take place in Nicosia, Cyprus. Contact ESO office for l3alkans and Middle East, N. Pavlidis, E. Andreopoulou Medica! School, Department of Medica! Oncology, University Hospital of loannina, 45rJO Ioannina, Greece; or call +30 651 99394 or +30 953 91083; or fax +30 651 97505 13reast cancer Deccn1/IC/; 1999 The ESO training coursc "Breast Reconstructive and Cancer Surgcry" will take place in Paris, France. Contact ESO Office, Viale Beatrice d'Este 37, 2ffl 22 Milan, llaly; or call +39 0258317850; or fax +39 025832.1266: or e-mail esomi( odmerku flukonazola za zdravljenje vaginalne kandidoze klinicno pomembnih interakcij (11. ;. Pri veckratnih in vecjih odmerkih so možne interakcije s terlenadinom, cisapridom, :astemizotorn; varfarinorn, derivati sulfonilureje, hidroklorotiazidom, fenitoinom, rifampicinor;i, .. · · teofilinom, indinavirom in midazolamom. Nosecnost in dojenje: Nosecnica lahko le, ce je korist zdravljenja za mater vecja od tveganja za plod. Dojece matere naj s flukonazolom ne dojijo. Stranski ucinki: Povezani so predvsem s prebavni, napenjanje, bolecine v trebuhu, driska, zelo redko se pojavijo preobcL anafilaksija in angioedem -v tem primeru takoj prenehamo jemati zdra glivicnimi obolenji lahko pride do levkopenije in trombocitopenije in do povoearie :a encimov. Oprema in nacin izdajanja: 7 kapsul po 50 mg, 28 kapsul p.o ,100 ITI! · · · · Podrobnejše informacije so na voljo pri proizvajalcu. 150 mg. Na zdravniški recept. 1/99. Radiology 1111d 011cology Instructions for authors Editorial policy of the journal Radiology and Oncology is to publish original scientific pa­pers, professional papers, review articles, case reports and varia (editorials, reviews, short communications, professional information, book reviews, letters, etc.) pertinent to diag­nostic and interventional radiology, computer­ized tomography, magnetic resonance, ultra­sound, nuclear medicine, radiotherapy, clinical and experimental oncology, radiobiology, radiophysics and radiation protection. The Editorial Board requires that the paper has not been published or submitted for publication elsewhere: the authors are responsible for ali statements in their papers. Accepted articles become the property of the journal and there­fore cannot be published elsewhere without written permission from the editorial board. Papers concerning the work on humans, must comply with the principles of the declaration of Helsinki (1964). The approval of the ethical cornmittee must then be stated on the manu­script. Papers with questionable justification will be rejected. Manuscript written in English should be subrnitted to the Editorial Office in triplicate (the original and two copies), including the illustrations: Radiology and 011cology, Institute of Oncology, Vrazov trg 4, SI-1000 Ljubljana, Slovenia; (Phone: +386 6] 132 00 68, Tel./Fax: +386 61 133 74 10, E-mail: gsersa@ionko-i.si). Authors are also asked to submit their manu­scripts on a 3.5" 1.44 Mb formatted diskette. The type of computer and word-processing package should be specified (Word for Windows is preferred). All articles are subjected to editorial review and review by independent referee selected by the editorial board. Manuscripts which do not comply with the technical requirements stated herein will be returned to the authors for cor­rection before peer-review. Rejected manu­scripts are generally returned to authors, how­ever, the journal cannot be held responsible for their loss. The editorial board reserves the right to ask authors to make appropriate changes in the contents as well as grammatical and stylistic corrections when necessary. The expenses of additional editorial work and requests for reprints will be charged to the authors. General instructions• Radiology and Onco­logy will consider manuscripts prepared accor­ding to the Vancouver Agreernent (N Engl J Med 1991; 324: 424-8, BM] 1991; 302: 6772; JAMA 1997; 277: 927-34.). Type the manuscript double spaced on one side with a 4 cm margin at the top and left hand side of the sheet. Write the paper in grammatically and stylistically correct language. Avoid abbreviations unless previously explained. The technical