Deniz Belen

Posterior osseous bridging of C1

The sulcus of the vertebral artery is located behind the lateral mass of the atlas and in some cases is converted into a foramen by anomalous ossification known as the posterior ponticulus (osseous bridge). This study involved anatomical observations of 158 isolated anatomical specimens of dry C1 vertebrae. The incidence and types of posterior osseous bridging were identified for the 158 dry samples of atlas vertebrae. In nine (5.6%) dry C1 vertebrae, partial osseous bridging was detected (bilaterally in eight vertebrae and unilaterally on the left in one). Complete osseous bridging (arcuate foramen) was observed in six (3.8%) dry C1 vertebrae (bilaterally in one vertebra, unilaterally on the left in three, and on the right in two). Awareness of the types of posterior osseous bridging of C1 in craniocervical junction surgery is essential, and may be helpful in surgical interventions in this region.

Functional and clinical evaluation for the surgical treatment of degenerative stenosis of the lumbar spinal canal: Clinical article

OBJECT This study was designed to evaluate the efficacy of decompressive surgery for degenerative lumbar spinal stenosis (LSS) on a functional and clinical basis. METHODS A prospective analysis and follow-up of 125 consecutive patients with degenerative LSS between 2000 and 2006 were performed. All patients underwent surgery for lumbar stenosis. Functional evaluations of the patients were performed using a treadmill, the visual analog scale, and the Oswestry Disability Questionnaire (ODQ). These parameters were recorded before surgery and the 3rd month and 1st and 2nd years after treatment. The first symptom time (FST), maximal walking duration (MWD), and thecal sac cross-sectional area (CSA) before and after surgery were also recorded. Statistical relations between variables were calculated. RESULTS As patient ages increased, the CSA of the thecal sac decreased. Decompressive surgery reached the target according to the difference between the preoperative and postoperative thecal sac CSA. A correlation between the CSA of the thecal sac and FST, and between the CSA of the thecal sac and MWD could not be established. There was a significant correlation between the FST and MWD, and a negative correlation could be established between the MWD and the ODQ score. Surgery led to significant decreases in the ODQ score. Maximal improvement was observed in the 3rd month after decompressive surgery. CONCLUSIONS The treatment for LSS should be decided using functional criteria; radiological criteria may not correlate with the severity of the disease. Improvements following lumbar decompression surgery continued within 1 year of treatment according to the ODQ and did not change significantly thereafter.

Internal Reduction Established by Occiput-C2 Pedicle Polyaxial Screw Stabilization in Pediatric Atlantoaxial Rotatory Fixation

Atlantoaxial rotatory fixation is an uncommon disorder of childhood, which can be treated conservatively whendiagnosed early. Although spontaneous correction occasionally occurs, most of the patients usually benefit from collar or traction therapies. If there is no intervention or if all external therapeutic modalities fail, the deformity may become chronic and irreducible. In such rare cases, surgical correction and stabilization are needed to prevent future head and neck deformity or facial asymmetry. In this report we describe a novel surgical technique used in a pediatric case presenting with delayed type 2 atlantoaxial rotatory fixation, in whom all external reduction methods had failed. The patient’s deformity was treated by occiput-C2 pedicle polyaxial screw stabilization. This technique is effective for reducing the atlantoaxial fixation in children.

Freehand C1 lateral mass screw fixation technique: our experience.

BACKGROUND Although C1 lateral mass fixation technique is frequently performed in upper cervical instabilities, it requires the guidance of fluoroscopic imaging. The fluoroscopy guidance is time-consuming and has the risks of accumulative radiation. Biplane fluoroscopy is also difficult in upper cervical pathologic conditions because of the use of cranial fixations. This study aimed to demonstrate that unicortical C1 lateral mass screws could be placed safely and rapidly without fluoroscopy guidance. METHODS Between 2002 and 2008, 32 C1 lateral mass screws were inserted in 17 consecutive patients with various pathologic conditions involving either atlantoaxial or occipitocervical instability. RESULTS C1 screw lengths ranged from 18 to 32 mm. The atlantoaxial fixation was performed in 13 patients, and C1 lateral mass screws were added to the occipitocervical construct in 3 patients, to the posterior cervical construct in 2 patients, and to the cervicothoracic construct in 1 patient. In 2 patients, because C1 lateral mass screws could not be inserted unilaterally, C1 pedicle screw analogs were inserted. There were no screw malpositions or neurovascular complications related to screw insertion. Operation time and intraoperative bleeding of the isolated atlantoaxial fixations were retrospectively evaluated. The mean follow-up was 32.3 months (range, 7-59 months). No screw loosening or construct failure was observed within this period. Postoperatively, 4 patients complained of hypoesthesia, whereas one patient had superficial wound infection. CONCLUSION C1 lateral mass screws may be used safely and rapidly in upper cervical instabilities without intraoperative fluoroscopy guidance and the use of the spinal navigation systems. Preoperative planning and determining the ideal screw insertion point, the ideal trajections, and the lengths of the screws are the most important points.

CNS involvement of Langerhans cell histiocytosis. Report of 23 surgically treated cases

We present 23 cases of Langerhans cell histiocytosis with central nervous system (CNS) involvement. The major complaints were a mass on the cranial vault in fifteen (65 %), visual disturbance in four (16 %), polyurea-polydipsia in three (13 %), and progressive weakness in all extremities in one patient (4 %). Neurological examination revealed no abnormality in sixteen patients (70 %), cranial nerve palsy, visual field defect and optic atrophy in six (26 %) and paraparesis in one (4 %). Tumoral mass was found to be located on the cranial vault (65 %), in the suprasellar region (21 %) and in the spinal column (8 %). The cranium and spinal column were both involved in one patient. All patients underwent surgery; craniectomy with grossly total tumor excision plus cranioplasty (65 %), craniotomy with subtotal tumor excision (26 %), and vertebrectomy with grafting (13 %) were performed. The clinical radiological and histopathological features, as well as therapeutical considerations are discussed and the pertinent literature is reviewed.

Lamotrigine attenuates cerebral vasospasm after experimental subarachnoid hemorrhage in rabbits.

BACKGROUND Increasing evidence implicates voltage-dependent sodium and potassium channels, in addition to calcium channels of various types, in the pathophysiological development of cerebral vasospasm. This study investigated the ability of LTG, an antiepileptic drug with multi-ion channel inhibition properties, to prevent cerebral vasospasm and subsequent neural ischemia in a rabbit model of SAH. METHODS Thirty-five New Zealand white rabbits were assigned to 1 of 3 groups: (1) control (no SAH, saline injection); (2) SAH alone; (3) SAH + LTG, 20 mg/kg daily. Animals were killed 72 hours after SAH, then basilar artery lumen areas and arterial wall thickness were measured in all groups. The histological sections of the CA1 and CA3 regions and dentate gyri of the hippocampi were evaluated semiquantitatively for neural tissue degeneration. RESULTS In the SAH group, the mean luminal cross-sectional area of the basilar artery was reduced by 62% after SAH as compared with the non-SAH controls (P < .0001). After SAH, the vasospastic response was attenuated by 36% in animals treated with 20 mg/kg of LTG compared with the SAH group (P < .005). The mean luminal cross-sectional areas of the basilar artery were 279000 +/- 27000 microm(2) in the control group, 173000 +/- 17600 microm(2) in the SAH group, and 236000 +/- 10000 microm(2) in the SAH + LTG group. The differences between the SAH group and the LTG-treated group were statistically significant (P < .0001). Histological examination was done in 12 control, 12 SAH, and 9 SAH + LTG-treated animals. The mean degeneration score for the control group and SAH + LTG group was statistically significant (P = .012). The difference between the SAH group and SAH+ LTG group was also statistically significant (P = .006). CONCLUSIONS These findings demonstrate that oral administration of LTG has marked neuroprotective effect and significantly attenuates cerebral vasospasm after SAH, thus providing additional support for the role of non-L-type calcium channels and voltage-dependent sodium channels in vasospasm.

Unusual appearance of intracranial fibromuscular dysplasia : A case report

Fibromuscular dysplasia (FMD) of intracranial arteries is seen rarely and usually limited to the intrapetrosal internal carotid artery or carotid siphon. The authors report a case with recurrent subarachnoid hemorrhage diagnosed angiographically as FMD with extensive involvement of intracranial arteries. Angiography showed large fusiform dilata tions and multiple aneurysms along the left intracranial internal carotid artery into its major branches, middle cerebral and posterior communicating arteries, and tip of the basilar and posterior cerebral arteries. Such an angiographic appearance has not been previously reported. Radiologic findings are demonstrated and possible pathophysiologic mechanisms are discussed.

Leflunomide prevents vasospasm secondary to subarachnoid haemorrhage

SummaryBackground. Though cerebral vasospasm is one of the most serious complications of subarachnoid haemorrhage (SAH), its complex pathogenesis is poorly understood and available clinical treatment options are unsatisfactory. This study was designed to examine the efficacy of leflunomide, an immunomodulatory agent with inhibitory properties, on vascular smooth muscle cell proliferation and inflammation in a rabbit cerebral vasospasm model. Methods. Twenty-two adult New-Zealand rabbits were assigned to 4 groups: control, SAH, SAH plus vehicle, SAH plus leflunomide. Subarachnoid haemorrhage was induced by administration of 1 ml of fresh unheparinised autologous arterial blood into the cisterna magna. Oral leflunomide (2 mg/kg) or vehicle treatment was started 12 h after the induction of subarachnoid haemorrhage and administered once a day. Three days later, the animals were sacrificed and the basilar artery was examined histologically for the lumen area and the thickness of the vessel wall. Inflammatory reaction was also examined by counting white blood cells within the vessel wall by means of light microscopic examination using haematoxylin and eosin staining. Findings. Severe and moderate vasospasms were detected in the basilar artery of the SAH and SAH plus vehicle treated groups, respectively. Leflunomide effectively reduced the vasospasm of the basilar artery. Compared to the vehicle treated group, leflunomide significantly reduced the lumen area (p < 0.01) and hyperplasia of the vessel wall (p < 0.01). Although inflammatory response within the vessel wall was reduced in the leflunomide treated group, no statistical significance was found between groups (p = 0.07). Conclusion. This study demonstrates for the first time that leflunomide treatment attenuates cerebral vasospasm in a rabbit SAH model while inflammatory reaction in the vessel wall is not affected. Although further studies are needed to reveal its molecular mechanisms in relieving vasospasm, leflunomide may provide a therapeutic potential for human cerebral vasospasm induced by SAH.

Management of Spinal Disorders and Trauma in Avicenna's Canon of Medicine

WE STUDY HISTORY in an attempt to achieve a wide perspective of life and reality. Spinal disorders, particularly spine traumas and their complications, have been one of the most challenging problems throughout the history of medicine and, indeed, throughout the history of humanity. The pioneers and founders of scientific medicine committed much of their lives to understanding these disorders. There is a paucity of historical documentation. From the extraordinary efforts of early practitioners, we may glean insight relevant to the more effective treatment of such debilitating disorders. Ibn Sina (Avicenna), who lived in the medieval period, was one such physician. His principal book of medicine, The Canon, played a fundamental role in the practice of medicine in the Eastern and Western worlds between the 11th and 17th centuries. In this book, published in the 11th century, he provided detailed accounts of spinal disorders and strategies for their management. Here, we provide a brief review of Avicenna’s most significant points concerning spinal diseases and their treatment from the chapters of the Canon. Although, there are not basic differences from Hippocratic knowledge, this book contains some original contributions.

Preliminary experience with squid: a new liquid embolizing agent for AVM, AV fistulas and tumors.

AIM The aim of the present study was to analyze our experience with a new liquid embolic agent, Squid, for the treatment of cerebral vascular lesions. MATERIAL AND METHODS We present 28 patients who were treated with two formulations of Squid (Squid 18 and Squid 12). The lesions included 16 arteriovenous malformation (AVM)s (Spetzler-Martin grade 2 in 8, 3 in 6 and 4 in 2), 9 arteriovenous (AV) fistulas, 2 tumors (glomus tumor and angiofibroma) and 1 AICA aneurysm. Of the 9 patients presenting with hemorrhage, 6 were AVM, 2 were AVF and 1 was aneurysm. RESULTS The total obliteration rate of the AVMs was 37.5%. Fistulas were closed completely after combined treatment with surgery in 6 out of 9 patients, and one was sent to radiotherapy. There was no mortality. Two reported hemorrhages and thromboembolic complications resulted in permanent deficits in 3 patients. Pathologic examination revealed mild inflammatory reaction with infiltration of polymorphonuclear cells in 5 patients in whom surgery was performed immediately after embolization. Technical problems such as rupture, inability to remove or premature occlusion of the microcatheter related to the embolic agent were not recorded. CONCLUSION Squid is a safe and effective embolic agent for treatment of cerebral AVMs, AV fistulas, tumors and aneurysms with satisfactory obliteration rate.