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İstanbul, Turkey

Senkesen O.,Acibadem Kozyatagi Hospital | Tezcanli E.,Acibadem University | Buyuksarac B.,Bogazici University | Ozbay I.,Istanbul University
Medical Dosimetry

Radiation fluence changes caused by the dosimeter itself and poor spatial resolution may lead to lack of 3-dimensional (3D) information depending on the features of the dosimeter and quality assurance of dose distributions for high-dose rate (HDR) iridium-192 (192Ir) brachytherapy sources is challenging and experimental dosimetry methods used for brachytherapy sources are limited. In this study, we investigated 3D dose distributions of 192Ir brachytherapy sources for irradiation with single and multiple dwell positions using a normoxic gel dosimeter and compared them with treatment planning system (TPS) calculations. For dose calibration purposes, 100-mL gel-containing vials were irradiated at predefined doses and then scanned in an magnetic resonance (MR) imaging unit. Gel phantoms prepared in 2 spherical glasses were irradiated with 192Ir for the calculated dwell positions, and MR scans of the phantoms were obtained. The images were analyzed with MATLAB software. Dose distributions and profiles derived with 1-mm resolution were compared with TPS calculations. Linearity was observed between the delivered dose and the reciprocal of the T2 relaxation time constant of the gel. The x-, y-, and z-axes were defined as the sagittal, coronal, and axial planes, respectively, the sagittal and axial planes were defined parallel to the long axis of the source while the coronal plane was defined horizontally to the long axis of the source. The differences between measured and calculated profile widths of 3-cm source length and point source for 70%, 50%, and 30% isodose lines were evaluated at 3 dose levels using 18 profiles of comparison. The calculations for 3-cm source length revealed a difference of > 3mm in 1 coordinate at 50% profile width on the sagittal plane and 3 coordinates at 70% profile width and 2 coordinates at 50% and 30% profile widths on the axial plane. Calculations on the coronal plane for 3-cm source length showed > 3-mm difference in 1 coordinate at 50% and 70% and 2 coordinates at 30% profile widths. The point source measurements and calculations for 50% profile widths revealed a difference > 3mm in 1 coordinate on the sagittal plane and 2 coordinates on the axial plane. The doses of 3 coordinates on the sagittal plane and 4 coordinates on the axial plane could not be evaluated in 30% profile width because of low doses. There was good agreement between the gel dosimetry and TPS results. Gel dosimetry provides dose distributions in all 3 planes at the same time, which enables us to define the dose distributions in any plane with high resolution. It can be used to obtain 3D dose distributions for HDR 192Ir brachytherapy sources and 3D dose verification of TPS. © 2014 American Association of Medical Dosimetrists. Source

Ertem M.,Istanbul University | Ozben V.,Istanbul University | Gok H.,Acibadem Kozyatagi Hospital | Aksu E.,Istanbul University
Journal of Minimal Access Surgery

Small bowel obstruction associated with abdominal cocoon (AC) is a rarely encountered surgical emergency. This condition is characterised by a thick fibrous membrane which encases the small bowel partially or completely. It is usually difficult to be able to make a definitive diagnosis in the presence of obscure clinical and radiological findings. Diagnosis is usually made at laparotomy when the encasement of the small bowel within a cocoon-like sac is visualised. Here, we report on a 29-year-old male patient who presented with acute small bowel obstruction and was eventually diagnosed with AC at laparoscopy. In this case, laparoscopic excision of the fibrous sac and extensive adhesiolysis resulted in complete recovery. Although rare, the diagnosis of AC should be kept in cases of patients with intestinal obstruction combined with relevant imaging findings. Laparoscopy should also be considered for the management of this condition in suitable patients. Source

Kayatas S.,Zeynep Kamil Women and Children Diseases Training and Research Hospital | Meseci E.,Acibadem Kozyatagi Hospital | Tosun O.A.,Zeynep Kamil Women and Children Diseases Training and Research Hospital | Arinkan S.A.,Zeynep Kamil Women and Children Diseases Training and Research Hospital | And 2 more authors.
Clinical and Experimental Obstetrics and Gynecology

Objective: To evaluate the indications, intraoperative diagnoses, and complication rates of both diagnostic and operative hysteroscopic procedures. Materials and Methods: Five thousand four hundred seventy-four (5474) hysteroscopic procedures performed in the department of gynecologic endoscopy unit between May 2005 and December 2012 were retrospectively analyzed from the archives. Indications, intraoperative diagnosis, and complications of all gynecological endoscopic procedures are recorded. Results: Abnormal uterine bleeding in premenopausal and postmenopausal women was the most frequent indication for diagnostic hysteroscopies in 1,887 (40%) cases. The most common preoperative indication for operative hysteroscopy was endometrial polyps in 469 (55.7%) cases and submucous leiomyomas in 151 (17.9%) cases. In this series, the most common complication was uterine perforation which occured in 15 (0.27%) out of 5,474 cases and the rate for diagnostic hysteroscopy and operative hysteroscopy was 0.06% and 1%, respectively. Conclusion: Hysteroscopy is a safe and effective minimally invasive procedure with very low complication rate. Source

Ozen H.,Hacettepe University | Akyol F.,Hacettepe University | Toktas G.,Istanbul Teaching and Research Hospital | Eskicorapci S.,Pamukkale University | And 10 more authors.
Journal of Urology

Purpose: We investigated the efficacy of prophylactic radiotherapy for gynecomastia/breast pain induced by 150 mg bicalutamide in a prospective, randomized, multi-institutional trial. Materials and Methods: After definitive treatment for localized prostate cancer 125 patients were randomized to 12 Gy radiotherapy before bicalutamide as prophylactic radiotherapy (53) or bicalutamide only for nonprophylactic radiotherapy (72). The incidence of gynecomastia, breast pain and tenderness, and discomfort perceived by the patients was assessed by physical examination and direct questioning at 3, 6 and 12 months of followup. Results: At the end of 12 months the gynecomastia rate was 15.8% in the prophylactic group and 50.8% in the nonprophylactic group (p <0.001). On patient evaluation the breast enlargement rate was 34.4%. The severity of breast pain and tenderness was not different between the groups. The breast pain rate was 36.4% and 49.2% by 12 months in the prophylactic and nonprophylactic groups, and the rate of patients who felt discomfort from gynecomastia was 11.4% and 29.5%, respectively. Conclusions: In this prospective study the incidence of gynecomastia was not as high as previously believed. Although prophylactic breast irradiation seemed to decrease the gynecomastia rate in patients on 150 mg bicalutamide, our study proves that not all patients need prophylaxis since only 52% were significantly bothered by gynecomastia. Thus, individual assessment is needed to select patients who need prophylactic radiation while on 150 mg bicalutamide. © 2010 American Urological Association Education and Research, Inc. Source

Kan B.,Kocaeli University | Tasar F.,Hacettepe University | Korkusuz P.,Hacettepe University | Ersoy O.,Nigde University | And 4 more authors.
Lasers in Medical Science

Distraction osteogenesis (DO) is the application of traction to the callus formed between bone segments and stimulation of bone formation by creating stress on the callus with this traction. Shorten the duration of DO and increasing the capacity of bone formation is important to prevent the possible complications of DO. For this reason, it was considered that low-level laser therapy (LLLT) may affect positively DO and it can decrease the complication range by shortening the period. Unilateral mandibular distractors were applied on 16 female white New Zealand rabbit to prove this hypothesis with micro CT, plain radiograph and histomorphometric analyses. Eight rabbits were applied LLLT with GaAlAs laser on the distraction area during the distraction period. On the post-distraction 28th day, four rabbits from study group and four rabbits from control groups were sacrificed. The rest of the rabbits were sacrificed on post-distraction 56th day. As a result of this study, significant positive effects of LLLT on post-distraction 28th day were revealed with all analyses. In histomorphometrical analyses, new bone formation was significantly higher in short-term laser applied group comparing to that of short-term control group (p = 0.029). In both microCT and plain radiograph, the highest radioopacity values were observed in short-term laser group when compared with that of the controls (p = 0.043 and p = 0.025, respectively). Even though LLLT increased the healing capacity on short-term, it was not sufficient on long-term (post-distraction 56th day) healing. LLLT application on distraction period, activate healing on bone so it may decrease DO period. The result of this study should be supported with clinical studies and the most effective laser source, dose and application time should be revealed with experimental and clinical studies. © 2013 Springer-Verlag London. Source

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