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Öğe Does random pattern skin flap supply adequate circulation to the underlying muscle through musculocutaneous perforators by reverse flow? An experimental study(Thieme Medical Publ Inc, 2007) Yazar, Şükrü; Çetinkale, Oğuz; Demir, Mustafa; Demirkesen, Cuyan; Arslan, HakanAn experimental study was designed to examine whether the blood supply of the muscle would be maintained by a reverse flow from the random pattern skin flap through the musculocutaneous perforators. A flap model containing rat rectus abdominis muscle and randomly based overlying abdominal skin was designed. Sixty rats were divided into four experimental groups as follows. In group I, scintigraphy and microangiography were performed in 10 and 6 rats, respectively, immediately after flap elevation. In group II, scintigraphy and microangiography were performed in 10 and 6 rats, respectively, 2 days after flap elevation. In group III, surviving skin paddle area was evaluated in 16 rats 7 days after flap elevation. After evaluation of surviving skin paddle area, the same animals were used for microangiographic (n¼6) and scintigraphic (n¼10) studies at the same day. In group IV, histopathologic examination was done in six flap muscles each 2 and 6 weeks after flap elevation (n¼12). The mean percentage of surviving skin paddle area was 95.6 6.5% on postoperative day 7. Microangiography showed progressively developed blood flow from the skin to muscle through the musculocutaneous perforators in groups II and III, respectively. The radioisotope uptake of the operated muscle was 40.9 12.8% immediately after flap elevation (group I), 58.3 15.6% on postoperative day 2 (group II), and 70.7 25.6% on postoperative day 7 (group III). There was a significant difference only between group I and group III (p<0.05, analysis of variance). Histopathologically prominent atrophy, lipomatoses, and fibroses were revealed at week 6. The poor circulation and viability outcomes of the muscle revealed in the study are because of immediately insufficient blood microcirculation at the distal part of the random pattern skin flap.Öğe A retrospective multicenter evaluation of cutaneous melanomas in Turkey(Asian Pacific Organization Cancer Prevention, 2014) Gamsızkan, Mehmet; Yılmaz, İsmail; Büyükbabani, Nesimi; Demirkesen, Cuyan; Demiriz, Murat; Astarcı, Hesna MüzeyyenBackground: We defined melanoma distribution in a large series of Turkish patients and evaluated the prognostic parameters of melanomas. Materials and Methods: A total of 1574 patients' data was retrospectively collected at 18 centers in Turkey. Demographic characteristics were questioned and noted. Prognostic parametres were evaluated based on sentinel lymph node involvement. Results: Mean age was 56.7 (4-99) years. While 844 (53.6%) cases were male, 730 (46.4%) cases were female. One thousand four hundred forty-seven (92%) cases were invasive melanoma and 127 (8%) cases were in-situ melanoma. The most common histopathological form was the superficial spreading melanoma (SSM) which was found in 549 patients (37.9%). It was followed by nodular melanoma in 379 (26.2%), acral lentiginous melanoma (ALM) in 191 (13.2%) and lentigo maligna melanoma in 132 (9.1%), respectively. On univariate analysis, lymphovascular invasion (p<0.001), tumor thickness (p<0.001), histopathological subtype (p<0.001), Clark level (p=0.001), ulceration (p<0.001), >= 6/mm(2) mitosis (p=0.005), satellite formation (p=0.001) and gender (p=0.03) were found to be associated with sentinel lymph node positivity. Regression was associated with sentinel lymph node negativity (p=0.017). According to multivariate analysis, lymphovascular invasion and tumor thickness were significant independent predictive factors of SLN positivity. Patient age, tumor localization, precursor lesions, lymphocytic infiltration and neurotropism were not related with sentinel lymph node involvement. Conclusions: In this retrospective analysis, it was found that the prevalence of SSM is at a lower rate while the prevalence of ALM is at a higher rate when compared to western countries. According to Breslow index; most of the melanoma lesions' thickness were greater than 2 mm, corresponding Clark IV. Vascular invasion and tumor thickness are the most important factors for sentinel lymph node involvement.