Sait Sirin

The evaluation of surgical treatment options in the Chiari Malformation Type I.

AIM There have been several treatment modalities to reduce the volume of the syringomyelic cavity and the pressure on the brainstem in Chiari Malformation Type I (CM-I). Foramen magnum decompression with and without duroplasty were compared in this retrospective study. MATERIAL AND METHODS From 2003 to 2006, 27 patients suffering from CMI were operated on at our institute. The following were measured: the ratio of the syringomyelic cavity to the spinal cord; pre-operative tonsillar herniation from the foramen magnum; pre- and postoperative tonsillo-dural distance; and spinoposterior fossa dural angle. RESULTS 83.3 % of the patients in the non-duroplasty and 73.3% of the patients in the duroplasty group were symptom free. The ratio of syrinx regression was 28+/-10% in the non-duroplasty and 36+/-33% in the duroplasty group. The tonsillodural distance was 3.1+/-1.8 mm in the non-duroplasty and 4.6+/-2.1 mm in the duroplasty group (p>0.05). The spino-posterior fossa dural angle was 133.6+/-9.44 degrees preoperatively and 136.7+/-9.78 degrees postoperatively in the non-duroplasty (p=0.376); 123.7+/-11.7 degrees preoperatively and 129.8+/-11.1 degrees postoperatively in the duroplasty group (p=0.885); no significant difference was found postoperatively (p=0.55, z=1.92), respectively. One patient was re-operated in the non-duroplasty group and thereafter duroplasty was performed. CONCLUSION Almost the same clinical outcomes can be achieved with and without duroplasty. There might be an option to perform duroplasty if simple procedure fails.

Retrospective analysis of spinal missile injuries.

One hundred six patients with spinal missile injury from war zones were admitted to our department from 1994 to 2000. Functional recovery and complications in surgical and conservative treatment groups were evaluated. Sixty-five were treated surgically, of whom 55 (84%) had incomplete injuries (Frankel scores B, C, and D). In the conservative group, 28 (68%) had incomplete injuries. A total of 81 patients (53 in the surgical group, 28 in the conservative group) could be monitored for functional recovery. In the surgical group, 34 (64%) showed improvement, 15 (28%) were unchanged, and four (7%) worsened. In the conservative group, 17 (60%) improved, nine (32%) remained unchanged, and two (7%) worsened. Cerebrospinal fluid fistula was observed in ten patients, seven of them in the surgically treated group. Five of seven meningitides were seen in the surgically treated group. Surgical intervention is not essential for spinal gunshot injury; however, it may be beneficial for patients with CSF fistula, infectious and compressing foreign bodies in the injury site, instability, and rapid neurological deterioration.

Imaging of posterior fossa epidermoid tumors

OBJECTIVE Epidermoid tumors have similar radiologic characteristics with arachnoid cysts on routine imaging techniques. Since they warrant different therapeutic interventions, it is essential to differentiate the two pathologies and to assess operative results. PURPOSE The purpose of this study is to define the MR characteristics of epidermoid tumors in posterior fossa particularly on fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI). PATIENTS AND METHODS During a 10-year period, we operated 19 cases with epidermoid tumor of posterior fossa. The localization of the epidermoids was cerebellopontine angle in 16 patients, within the fourth ventricle in 2 patients and pineal region in 1 patient. Neuroimaging included CT in all patients, conventional MR in 14 patients and FLAIR and DWI in the last 6 patients. RESULTS In the first 13 cases, diagnosis of epidermoid tumor was difficult on CT and conventional MR. Epidermoids appeared as heterogeneous hyperintense lesions on FLAIR and homogenous hyperintense lesions on DWI in the last 6 patients. While total resection of the tumor was achieved in 17 patients, subtotal resection was performed in 2 patients. Histopathological examinations of the specimens revealed epidermoid tumor in all cases. CONCLUSION Advances in neuroradiology provide us advantages for planning the treatment modalities in epidermoid tumors of the posterior fossa. The difficulties in preoperative differential diagnosis and judgment for reoperation in the postoperative course have been decreased particularly via FLAIR and DWI.

A rare reason of foot drop caused by primary diffuse large b-cell lymphoma of the sciatic nerve: case report

IntroductionPrimary central nervous system lymphomas account for 2% of all malignant lymphomas. Although the involvement of peripheral nerves has been previously described as a dissemination of systemic lymphomas or a direct extension to the nerve trunk from contiguous lymphomas, primary involvement of the sciatic nerve is extremely rare.CaseTo the best of our knowledge, the primary localization of lymphoma within sciatic nerve has been reported only nine times. We report, a very rare example of a primary diffuse large B-cell lymphoma of the sciatic nerve.DiscussionThe patient presented with atypical sciatica. Such symptoms can be misdiagnosed as lumbar disc pathology and magnetic resonance imaging and electrophysiological studies avoid this misinterpretation.

Management of patients with recurrent glioblastoma using hypofractionated stereotactic radiotherapy.

Background Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. The chance of cure is very limited due to treatment-refractory disease course with frequent recurrences despite aggressive multimodality management. In this retrospective study, we evaluated treatment outcomes of hypofractionated stereotactic radiotherapy (HFSRT) in the management of recurrent GBM and report our single-center experience. Methods Twenty-eight patients receiving HFSRT for recurrent GBM between September 2008 and February 2014 were retrospectively assessed. Total radiotherapy dose was 25 Gy delivered in 5 fractions over 5 consecutive days for all patients. High-precision, image-guided volumetric modulated arc therapy was delivered with a linear accelerator using 6-MV photons using the frameless technique. Analyzed prognostic factors were age, gender, Karnofsky performance status (KPS), tumor location, planning target volume (PTV) size, overall survival (OS), progression-free survival (PFS), time interval between completion of treatment with Stupp protocol at primary diagnosis and recurrence. Results Median follow-up time was 42 months (range 2–68). Median time interval between primary chemoradiotherapy and HFSRT was 11.2 months (range 4–57.9). Median OS and PFS calculated from reirradiation was 10.3 months and 5.8 months, respectively. Longer interval between initial treatment and recurrence (p = 0.01), smaller PTV size (p = 0.001), KPS ≥70 (p = 0.005) and younger age (p = 0.004) were associated with longer OS on statistical analysis. Conclusion HFSRT offers a feasible and effective salvage treatment option for recurrent GBM management. Prognostic factors associated with longer OS in our study were longer interval between initial treatment and recurrence, smaller PTV size, KPS ≥70 and younger age.

Bilateral Carpal Tunnel Syndrome with Type 1 Diabetes mellitus in Childhood

The differences between diabetic mono- or polyneuropathy and entrapment neuropathy are most important with respect to choosing treatment alternatives in pediatric patients. A 7-year-old girl with type 1 diabetes mellitus was admitted to our clinic with a complaint of bilateral weakness in her hands. Her clinical findings and electromyography study revealed an entrapment neuropathy of the median nerve at the wrist. She underwent operation by open carpal tunnel release. All symptoms resolved within 6 months after the operation. Carpal tunnel syndrome, especially bilateral, is very rare in childhood and it can be treated surgically.

Management of patients with ≥4 brain metastases using stereotactic radiosurgery boost after whole brain irradiation.

Aims and Background Brain metastases are a prevalent consequence of systemic cancer, and patients suffering from brain metastases usually present with multiple metastatic lesions. An overwhelming majority of the available literature assessing the role of stereotactic radiosurgery in brain metastasis management includes patients with up to 4 metastases. Given the significant benefit of stereotactic radiosurgery for the treatment of 1 to 3 brain metastases, we evaluated the use of stereotactic radiosurgery boost after whole brain irradiation in the management of patients with ≥4 brain metastases. Methods In this retrospective analysis, outcomes of 50 patients who underwent linear accelerator-based stereotactic radiosurgery boost within 4 to 6 weeks of whole brain irradiation for ≥4 brain metastases were assessed in terms of local control, overall survival, primary involved organ, recursive partitioning analysis class and Karnofsky performance status at the time of stereotactic radiosurgery, number of lesions, age, status of the primary cancer (controlled vs uncontrolled), presence of extracranial disease and toxicity. Results Fifty patients with ≥4 brain metastases were treated using linear accelerator-based stereotactic radiosurgery boost after whole brain irradiation between April 1998 and April 2013. Mean and median number of intracranial lesions was 6.02 and 6, respectively. Median lesion volume was 10.9 cc (range, 0.05–32.6). Median survival time after radiosurgery was 10.1 months (range, 1–25). Status of the primary cancer (controlled vs uncontrolled), recursive partitioning analysis class, Karnofsky performance status, and extracranial metastasis showed statistically significant correlations with overall survival (P <0.001). Treatment-related side effects after stereotactic radiosurgery included temporary edema (n = 14, 28%), hemiparesis (n = 1, 2%), seizure (n = 1, 2%), leukoencephalopathy (n = 2, 4%), and radiation necrosis (n = 6, 12%). Conclusions Linear accelerator-based stereotactic radiosurgery boost within 4 to 6 weeks after whole brain irradiation proved to be an efficacious and well-tolerated treatment strategy for the management of patients with ≥4 brain metastases in our study.

Evaluation of linear accelerator-based stereotactic radiosurgery in the management of glomus jugulare tumors.

AIMS AND BACKGROUND Although mostly benign and slow-growing, glomus jugulare tumors have a high propensity for local invasion of adjacent vascular structures, lower cranial nerves and the inner ear, which may result in substantial morbidity and even mortality. Treatment strategies for glomus jugulare tumors include surgery, preoperative embolization followed by surgical resection, conventionally fractionated external beam radiotherapy, radiosurgery in the form of stereotactic radiosurgery or fractionated stereotactic radiation therapy, and combinations of these modalities. In the present study, we evaluate the use of linear accelerator (LINAC)-based stereotactic radiosurgery in the management of glomus jugulare tumors and report our 15-year single center experience. METHODS AND STUDY DESIGN Between May 1998 and May 2013, 21 patients (15 females, 6 males) with glomus jugulare tumors were treated using LINAC-based stereotactic radiosurgery at the Department of Radiation Oncology, Gulhane Military Medical Academy. The indication for stereotactic radiosurgery was the presence of residual or recurrent tumor after surgery for 5 patients, whereas 16 patients having growing tumors with symptoms received stereotactic radiosurgery as the primary treatment. RESULTS Median follow-up was 49 months (range, 3-98). Median age was 55 years (range, 24-77). Of the 21 lesions treated, 13 (61.9%) were left-sided and 8 (38.1%) were right-sided. Median dose was 15 Gy (range, 10-20) prescribed to the 85%-100% isodose line encompassing the target volume. Local control defined as either tumor shrinkage or the absence of tumor growth on periodical follow-up neuroimaging was 100%. CONCLUSIONS LINAC-based stereotactic radiosurgery offers a safe and efficacious management strategy for glomus jugulare tumors by providing excellent tumor growth control with few complications.

Management of vestibular schwannomas with linear accelerator-based stereotactic radiosurgery: a single center experience.

AIMS AND BACKGROUND The primary goal of treatment for vestibular schwannoma is to achieve local control without comprimising regional cranial nerve function. Stereotactic radiosurgery has emerged as a viable therapeutic option for vestibular schwannoma. The aim of the study is to report our 15-year single center experience using linear accelerator-based stereotactic radiosurgery in the management of patients with vestibular schwannoma. METHODS AND STUDY DESIGN Between July 1998 and January 2013, 68 patients with unilateral vestibular schwannoma were treated using stereotactic radiosurgery at the Department of Radiation Oncology, Gulhane Military Medical Academy. All patients underwent high-precision stereotactic radiosurgery using a linear accelerator with 6-MV photons. RESULTS Median follow-up time was 51 months (range, 9-107). Median age was 45 years (range, 20-77). Median dose was 12 Gy (range, 10-13) prescribed to the 85%-95% isodose line encompassing the target volume. Local tumor control in patients with periodic follow-up imaging was 96.1%. Overall hearing preservation rate was 76.5%. CONCLUSIONS Linear accelerator-based stereotactic radiosurgery offers a safe and effective treatment for patients with vestibular schwannoma by providing high local control rates along with improved quality of life through well-preserved hearing function.