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    1H magnetic resonance spectroscopy of the normal testis
    (Elsevier Science Inc, 2008) Firat, Ahmet Kemal; Ugras, Murat; Karakas, Hakk M.; Erdem, Gulnur; Kurus, Meltem; Ugras, Meltem; Celik, Tayfun
    Purpose: The purpose of this study was to determine the pre- and postpubertal H-1 magnetic resonance spectroscopic characteristics of the normal testis to establish baseline values for further clinical studies. Materials and Methods: The subjects consisted of male volunteers, of whom 19 were prepubertal with ages between 7 and 13 years and 24 were postpubertal with ages between 19 and 39 years. Their testes were evaluated at 1.5 T with magnetic resonance spectroscopy; in addition, testis volumes were measured. Major metabolite peaks were identified and their ratios were calculated. Metabolite differences of testis between pre- and postpubertal age were analyzed. Results: Major constituents of spectra were 3.21 ppm choline and 0.9-1.3 ppm lipid peaks. At the echo time (TE) spectrum of 31 ms, choline/lipid ratios ranged from 0.35 to 8.30 (mean=1.87) in postpubertal males and from 0.06 to 5.45 (mean=0.88) in prepubertal males (P<.013). At the TE spectrum of 136 ms, choline/lipid ratios ranged from 0.66 to 15.42 (mean=4.09) in postpubertal males and from 0.05 to 4.91 (mean=0.9) in prepubertal males (P<.016). Conclusions: Choline/lipid ratio was higher in the postpubertal period. The existence of higher choline peak in that age group should be due to the initiation of spermatogenesis. The decrease in the lipid peak may represent the effect of testosterone on testicular tissue or may be due to histochemical changes initiated by puberty. The significant decrease in choline/lipid ratio noted after puberty could represent the presence of spermatogenesis. This hypothesis should be evaluated by further studies on postpubertal. subjects with impaired spermatogenesis. (C) 2008 Published by Elsevier Inc.
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    Bile duct anatomy of the Anatolian Caucasian population: Huang classification revisited
    (Springer France, 2008) Karakas, Hakki Muammer; Celik, Tayfun; Alicioglu, Banu
    Background and objectives Living donor liver transplantations (LDLT) donor candidates are being assessed with MRCP (magnetic resonance cholangiopancreatography) to identify their suitability for standard surgical techniques. Variations of the bile duct anatomy play an important role in donor selection and in the selection of the resection technique. If bile duct anatomy is misrecognized, complications may occur. Anatomic variations are classified according to the origin of the right posterior hepatic duct (RPHD). According to the so called Huang classification, type A1 is the most, and type A5 is the least frequent variation. These frequencies were initially validated on Chinese population. Later studies revealed significant variability in frequency for the so called trifurcation, the variation in which a common junction of RHPD, right anterior hepatic duct (RAHD) and left hepatic duct (LHD) (A2) exists. In this study we aimed to determine the bile duct anatomy variations for the Anatolian Caucasians. Methods One hundred and thirty-four healthy subjects were investigated under 1.5 T MRI, with breath-hold (expiration) heavily T2-weighted turbo spin echo (TSE) static fluid imaging (TR/TE = 8,000/800). The sequence has permitted three to five oblique coronal thick sections (40 mm) around a common axis. Sequences were repeated until anatomically interpretable images were obtained. Diagnostic images could not be obtained in 22 subjects. Radiologists who were fully experienced in LDLT assessment investigated these images, and classified them for the surgical variations of the bile duct anatomy. One hundred and twelve subjects (58 men, 54 women) who were classified were between 14 and 81 years of age (mean: 39.3; SD 14.1). According to Huang classification, 61 of them (55%) were classified as type A1 (normal right and left hepatic duct junction), 16 (14%) as type A2 (common junction of RAHD, RHPD and LHD), 24 (21%) as type A3 (aberrant drainage of RPHD to left main duct), and 11 (10%) as type A4 (aberrant drainage of RPHD to main hepatic duct). When subjects, in whom the distance (d) between RPHD insertion and the right and left hepatic duct junction is less than 1 cm, are classified as type A2, the type A1 prevalence decreases to 28%. For the entire population that distance was between 3 and 25 mm (mean: 9.8, SD: 4.8). Accordingly, the frequency of type A1 anatomy was 8-29% lower than the respective frequency in Chinese population. Conclusion From the surgical perspective, close proximity (d < 1 cm) of RPHD to right and left hepatic duct junction is considered as type A2 variation. According to that concept, type A1, usually accepted as the dominant anatomic variation, is encountered only in 28% of the Anatolian Caucasians. We have proposed a modified surgical classification in which Huang type 2 was subdivided into types K2a (close proximity) and K2b (trifurcating). The predominance of K2 types in the population of the study may necessitate the use of bench ductoplasty in many liver grafts.
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    Subcutaneous Fat Necrosis Mimicking a Malignant Mass Associated with the Left Internal Oblique and the Sartorius Muscles in a 3 Months Old Boy: Differential Diagnosis
    (Ortadogu Ad Pres & Publ Co, 2009) Sigirci, Ahmet; Karaman, Abdurrahman; Bassullu, Nuray; Celik, Tayfun
    Subcutaneous fat necrosis (SCFN) is a rare, self-limited and benign disorder that develops after birth. A 3-month-old-boy presented with a semi-mobile mass under the skin without erythema on the left inguinal area. Ultrasound (US) revealed a mass within the subcutaneous fat layer over the left internal oblique and the sartorius muscles with heterogenous echogenicity. Computed tomograpy (CT) showed that the mass had a smooth border with partially spicular extensions to the subcutaneous fat. The presumptive diagnosis was rhabdomyosarcoma. Surgical exploration and excision biopsy were performed. The pathological examination revealed SCFN.
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    Synovial Chondromatosis of the Temporomandibular Joint: Radiologic and Histopathologic Findings
    (Lippincott Williams & Wilkins, 2012) Kahraman, Aysegul Sagir; Kahraman, Bayram; Dogan, Metin; Firat, Cemal; Samdanci, Emine; Celik, Tayfun
    Synovial chondromatosis is a formation of multiple intrasynovial nodules resembling osteochondromas, resulting from proliferative changes in the synovial linings of joints; as the disorder progresses, nodules increasingly withdraw from the intrasynovial areas for the joint cavities. This is a relatively unusual case that can arise at unilateral large joints, such as knee, hip, and elbow, with the temporomandibular joint being the rarest one of them. Early recognition of the signs and symptoms with resultant accurate diagnosis, as well as proper surgical treatment, offers patients the best hope of recovery and improved quality of life. We report a conventional radiologic film, computed tomography, magnetic resonance imaging, and histopathologic findings of the synovial chondromatosis presenting as a large right preauricular mass arising from the temporomandibular joint without bone destruction.