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Permanent URI for this collectionhttps://hdl.handle.net/20.500.14288/3
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Publication Metadata only Clinical results of anterior odontoid screw fixation for type II odontoid fractures(Turkish Neurosurgical Society, 2014) Keskin, Fatih; Gomleksiz, Cengiz; Sasani, Mehdi; Oktenoglu, Tunc; Suzer, Tuncer; Özer, Ali Fahir; Faculty Member; School of Medicine; 1022AIM: In this study, 31 patients with a diagnosis of Type II odontoid fractures were reported. All patients were treated with anterior transodontoid screw fixation and clinical outcomes were reported. MATERIAL and METHODS: In this study, the retrospective clinical analysis of 31 patients with traumatic type II odontoid fractures who were treated through anterior transodontoid fixation in Neurosurgery Department at VKV American Hospital between 1998 and 2012 was performed. The age, sex, cause of injury, diagnosis time, neurological examination before and after surgery, follow-up period were evaluated. The neurological status of patients was classified according to the Frankel scale. RESULTS: In 4 patients, 2 transodontoid screws were inserted. The mean hospital stay was 3.35 days. Posterior occipito-cervical fusion was done in 1 patient due to the lack of fusion in the first operation. No vascular injury, screw malposition, infection, neurologic deterioration, or complications were observed during the peroperative and postoperative stage. The mean postoperative follow-up period was 36 months after surgery. Radiological imaging of patients were performed at the early and late postoperative stage. CONCLUSION: We found satisfying fusion rates and better patient comfort during the postoperative period. We think that stabilization and fusion through a transodontoid screw is a minimal invasive method.AMAÇ: Çalışmada, Tip II odontoid fraktürü tanısı alan 31 olgu bildirilmiştir. Olguların hepsi anterior transodontoid vida fiksasyonu ile tedavi edilmiş ve klinik sonuçları bildirilmiştir. YÖNTEM ve GEREÇLER: Çalışma, VKV Amerikan Hastanesi Nöroşirürji Bölümü’nde 1998-2012 yılları arasında travmatik tip II odontoid kırığı nedeniyle anterior transodontoid fiksasyon ile cerrahi tedavi uygulanan 31 hastanın retrospektif klinik analizleri yapılmıştır. Tüm olguların yaş, cinsiyet, travma nedeni, teşhis zamanı, cerrahi girişim öncesi ve sonrasında nörolojik muayeneleri, takip süresi değerlendirilmiştir. Olguların nörolojik durumları Frankel skalasına göre sınıflandırılmıştır. BULGULAR: Dört hastaya 2 adet transodontoid vidası yerleştirildi. Hastanede kalış süresi ortalama 3,35 gün idi. 1 hastada postop takibinde füzyon oluşmaması nedeniyle ikinci bir operasyon ile posteriordan oksipitoservikal füzyon yapıldı. İşlem sırasında ve sonrasında damar yaralanması, vida malpozisyonu, enfeksiyon, nörolojik bozulma gibi komplikasyonlar izlenmedi. Hastalar ameliyat sonrasında ortalama 36 ay takip edildi. Hastaların erken ve geç dönemde radyolojik görüntülemeleri yapıldı. SONUÇ: Postoperatif dönemde hastaların takiplerinde tatmin edici füzyon oranı ve hasta konforunun daha iyi olduğunu saptadık. Tip II odontoid kırıklarının cerrahi tedavisinde minimal invaziv yöntem olan transodontoid vida ile fiksasyonun yüksek avantajlarından dolayı ilk seçenek olabileceğini düşünüyoruz.Publication Metadata only Response to microsurgical anatomy of lumbosacral spinal roots(Springer, 2015) Çavdar, Safiye; Faculty Member; School of Medicine; 1995Publication Metadata only Superior epididymal artery-based paraepididymal adipofascial flap(Lippincott Williams and Wilkins (LWW), 2023) Cinar, Fatih; Yalcin, Can Ege; Celik, Ugur; Demiroz, Anil; Baghaki, Semih; Cetinkale, Oguz; N/A; Ayas, Görkem; Undergraduate Student; School of Medicine; N/ABackground: Flap surgery is widely performed in reconstructive surgery. Experimental research is vital to improve flap viability. However, the number of flap models for animals is still limited. In this study, we define a new adipofascial flap in rats that can be used to investigate pedicled flap and/or adipofascial flap physiology.Methods: Eight Wistar male rats were used. Under deep anesthesia, paraepididymal adipofascial flaps were harvested. Flap perfusion was assessed using a near-infrared fluorescence imaging system. The length of the flap and the diameter of the flap pedicle were measured.Results: All animals (n = 8) had sufficient sizes of paraepididymal fat pad, and no animals were lost. The only postoperative complication was testicular hematoma, which was observed in 2 animals. The maximum length of the harvested paraepididymal adipofascial flap was 9.7 cm with a mean of 6.6 cm. The maximum width of the flap was 3.3 cm with a mean of 2.6 cm. The mean pedicle diameter of the paraepididymal adipofascial flap was 1.1 mm. Near-infrared fluorescence imaging revealed adequate perfusion in all flaps.Conclusions: The number of reported adipofascial flap models in animals is low, and they are mostly limited to flaps based on epigastric vessels. Superior epididymal artery-based paraepididymal adipofascial flap can be used as a pedicled flap model for studies focusing on adipofascial and/or pedicled flap physiology. Uncomplicated surgical technique and short operative time make this flap a valuable alternative to other flap models.Publication Metadata only Late tricuspid regurgitation after percutaneous transcatheter closure of ventricular septal defect: an educational presentation(Sociedade Brasileira de Cirurgia Cardiovascular, 2021) Sarkışlalı, Kamil; N/A; Kalangos, Afksendiyos; Faculty Member; School of Medicine; 286247Transcatheter closure of ventricular septal defects (VSD) is not out of complications. Late complications are rare, but important, and sometimes require surgical correction. Herein, we report a case of tricuspid regurgitation as a complication of transcatheter VSD closure. The patient underwent successful surgery. Postoperative course was satisfactory. Echocardiographic examination revealed well-functioning tricuspid valve. We present this case since valve regurgitation after transcatheter procedure requiring surgery is an uncommon but significant complication due to heart failure risk. Even in the absence of any clinical finding, post-procedural close follow-up is important for early diagnosis of the problem to prevent the aforementioned risk.Publication Metadata only Gamma knife radiosurgery for hemorrhagic brainstem cavernomas(Turkish Neurosurgical Soc, 2019) Üçüncü Kefeli, Ayşegül; Şengöz, Meriç; N/A; Peker, Selçuk; Faculty Member; School of Medicine; Koc University Hospital; 11480AIM: To assess treatment results of gamma knife radiosurgery (GKRS) for hemorrhagic brainstem cavernous malformations (BSCMs). MATERIAL and METHODS: A retrospective review of patients with hemorrhagic BSCMs, who were treated at the Acibadem Kozyatagi Hospital GKRS unit from May 2007 to October 2015 was performed. RESULTS: In total, 82 patients were identified. All patients had experienced at least one hemorrhagic event (range 1-3), and all of them presented with radiological evidence of hemorrhage. The median target volume was 0.3 ml, and the median marginal radiation dose was 12 Gy. The mean durations before and after surgery were 25.5 (range 1-204) months, and 50.3 (range 13-113) months, respectively. Pre-treatment hemorrhage rates were calculated from the date of first hemorrhage to the date of radiosurgery. There were 97 bleeds over 174.4 patient-years during the observation period, with an annual hemorrhage rate of 55.7%. If the first bleed is excluded, the annual hemorrhage rate was 8.6%. Only three patients demonstrated re-bleeding, which occurred at 3, 12 and 79 months after radiosurgery. Over a total follow up time of 344 patient-years the annual re-bleeding rate was therefore 0.87%, indicating that the risk of BSCM hemorrhage was significantly decreased by radiosurgery. CONCLUSION: GKRS was a safe and effective treatment for symptomatic low volume BSCMs when a low marginal dose is used. A randomized controlled trial is needed that compares GKRS to observation if we want to establish the true efficacy of this treatment.Publication Metadata only Stereotactic radiosurgery for intracranial chordomas: an international multiinstitutional study(American Association of Neurological Surgeons (AANS), 2022) Pikis, Stylianos; Mantziaris, Georgios; Nabeel, Ahmed M.; Reda, Wael A.; Tawadros, Sameh R.; El-Shehaby, Amr M. N.; Abdelkarim, Khaled; Eldin, Reem M. Emad; Sheehan, Darrah; Sheehan, Kimball; Liscak, Roman; Chytka, Tomas; Tripathi, Manjul; Madan, Renu; Speckter, Herwin; Hernandez, Wenceslao; Barnett, Gene H.; Hori, Yusuke S.; Dabhi, Nisha; Aldakhil, Salman; Mathieu, David; Kondziolka, Douglas; Bernstein, Kenneth; Wei, Zhishuo; Niranjan, Ajay; Kersh, Charles R.; Lunsford, L. Dade; Sheehan, Jason P.; N/A; Peker, Selçuk; Samancı, Mustafa Yavuz; Faculty Member; Faculty Member; School of Medicine; School of Medicine; 11480; 275252Objective: the object of this study was to evaluate the safety, efficacy, and long-term outcomes of stereotactic radiosurgery (SRS) in the management of intracranial chordomas. Methods: this retrospective multicenter study involved consecutive patients managed with single-session SRS for an intracranial chordoma at 10 participating centers. Radiological and neurological outcomes were assessed after SRS, and predictive factors were evaluated via statistical methodology. Results: a total of 93 patients (56 males [60.2%], mean age 44.8 years [SD 16.6]) underwent single-session SRS for intracranial chordoma. SRS was utilized as adjuvant treatment in 77 (82.8%) cases, at recurrence in 13 (14.0%) cases, and as primary treatment in 3 (3.2%) cases. The mean tumor volume was 8 cm(3) (SD 7.3), and the mean prescription volume was 9.1 cm(3) (SD 8.7). The mean margin and maximum radiosurgical doses utilized were 17 Gy (SD 3.6) and 34.2 Gy (SD 6.4), respectively. on multivariate analysis, treatment failure due to tumor progression (p = 0.001) was associated with an increased risk for post-SRS neurological deterioration, and a maximum dose > 29 Gy (p = 0.006) was associated with a decreased risk. A maximum dose > 29 Gy was also associated with improved local tumor control (p = 0.02), whereas the presence of neurological deficits prior to SRS (p = 0.04) and an age > 65 years at SRS (p = 0.03) were associated with worse local tumor control. The 5- and 10-year tumor progression-free survival rates were 54.7% and 34.7%, respectively. An age > 65 years at SRS (p = 0.01) was associated with decreased overall survival. The 5- and 10-year overall survival rates were 83% and 70%, respectively. Conclusions: SRS appears to be a safe and relatively effective adjuvant management option for intracranial chordomas. The best outcomes were obtained in younger patients without significant neurological deficits. Further well-designed studies are necessary to define the best timing for the use of SRS in the multidisciplinary management of intracranial chordomas.Publication Metadata only P-139 the effects of the incision type on incisional hernia results of living donor liver transplant; single center experience(Oxford University Press (OUP), 2022) Tırnova, İsmail; N/A; N/A; Kanmaz, Turan; N/A; Faculty Member; N/A; School of Medicine; Koç University Hospital; N/A; 275799Publication Metadata only Contemporary strategies to improve the outcome in locally advanced pancreatic cancer(Edizioni Medico Scientifiche, 2017) Schneider, Rick; Spath, Christoph; Nitsche, Ulrich; Kleeff, Jorg; Erkan, Murat Mert; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Koç University Hospital; 214689Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with an overall 5-year survival rate of less than 7%. After many years of basic and clinical research efforts, pancreatic cancer patients presenting with locally advanced, unresectable tumors remain a therapeutic challenge. Despite the lack of high quality randomized controlled trials, perioperative/neoadjuvant treatment strategies seem to be beneficial in these patients. At present the FOLFIRINOX regimen, which was established in the palliative setting, is increasingly recognized as the backbone of neoadjuvant therapy for locally advanced PDAC. Surgical resection follows the same principles and guidelines as upfront surgery specifically regarding the extent of resection including lymphadenectomy, vascular resections and multivisceral resections. Because of the limited diagnostic accuracy of restaging after neoadjuvant treatment, an adjusted intraoperative strategy is necessary to minimize the risk of debulking procedures and maximize the chance of a potential curative resection. Locally advanced PDAC requires a multidisciplinary and individualized treatment approach, and further research efforts for novel and innovative therapies. This article provides an updated overview on strategies to improve the outcome in locally advanced PDAC.Publication Metadata only Intradural communication between dorsal rootlets of spinal nerves: their clinical significance(Springer, 2015) Solmaz, Bilgehan; Tatarli, Necati; Ceylan, Davut; N/A; Keleş, Güven Evren; Çavdar, Safiye; Faculty Member; Faculty Member; School of Medicine; School of Medicine; N/A; 1995Background Anatomical and surgical textbooks give almost no attention to the intradural communications between dorsal rootlets of adjacent spinal nerves. These communications can be of significance in various neurosurgical procedures and clinical conditions of the region. Methods The spinal cord of six formaldehyde-fixed cadavers was dissected from C1–S5. The dorsal rootlets of the spinal nerves were exposed via a posterior approach and communications between adjacent spinal nerves were documented. Results The frequency of communication between adjacent dorsal rootlets of the spinal nerves showed variations among spinal levels. Thirty-eight dorsal rootlet communications were observed in six cadavers (12 sides) and 20 (52.6 %) were at cervical levels, 14 (36.8 %) at thoracic levels, and four (10.5 %) at lumbar levels. The majority of communications were observed on the left side (65.8 %). Communications were most frequently observed at cervical (C4–C5, C5–C6) and upper thoracic (T1–T2) levels and seen least frequently at lower thoracic and lumbar levels. No communications were observed at sacral levels. Five types of communication were observed: I. oblique ascending, II. oblique descending III. short Y, IV. long Y and V shaped. None of the communication extended beyond one segment at any spinal level. The occurrence of such dorsal rootlet communications ranged from 3 to 7 for each cadaver and the mean was 4.8±1.3. Histological sections from various levels of the dorsal rootlet communications showed that all consisted of myelinated fibers of varying diameters. Conclusions Such communications may lead to misinterpretation of the pathology on the basis of clinical signs and symptoms and also should be considered in rhizotomy.Publication Metadata only Poorly cohesive (signet ring cell) carcinoma of the ampulla of vater(Sage, 2020) Tuncel, Deniz; Basturk, Olca; Bradley, Kyle T.; Kim, Grace E.; Xue, Yue; Reid, Michelle D.; Balci, Serdar; Erbarut, Ipek; N/A; Adsay, Nazmi Volkan; Faculty Member; School of Medicine; 286248In the ampulla of Vater, carcinomas with "diffuse-infiltrative"/"signet ring cell" morphology, designated as "poorly cohesive carcinoma" (PCC) in the WHO classification, are very rare and poorly characterized. Nine cases with a classical PCC morphology constituting >50% of the tumor were identified. Mean age was 64.8 years (vs 64.6 in ampullary carcinomas [ACs]) and 6 were males, 3 females. The mean invasive tumor size was 2.5 cm (vs 1.9 in ACs). Other morphologic patterns displayed included cord-like infiltration (n=2), plasmacytoid cells (n=2), and microglandular component (n=4), including goblet cell adenocarcinoma-like foci. None of the cases were associated with dysplasia. By immunohistochemistry, the carcinomas did not show intestinal differentiation (CDX2 0/9, CK20 1/9, MUC2 3/9), MUC1 was positive in 4/9, MUC5AC was positive in 7/8. E-cadherin loss was noted in 4/9. All cases were advanced stage (6/9-pT3, 3/9-pT4) (vs 43% in ACs). Lymph node metastases were identified in 44% (vs 45% in AC). Six patients (67%) died of disease at a median of 25 months, 3 were alive at 13, 15, and 60 months. Overall median survival was significantly worse than that of intestinal-type ACs (26 vs 122 months, P = .006) and trended toward worse than pancreatobiliary type (26 vs 42 months, P = .1). In conclusion, PCCs constitute 2.45% of all ACs. These present as advanced tumors and express upper-gastrointestinal immunoprofile with frequent MUC5AC labeling, which may be helpful in identifying subtle infiltration in the surface mucosa since MUC5AC is not expressed in the ampullary mucosa. Patients have poor prognosis.