Mehdi Sasani
Koç University
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Featured researches published by Mehdi Sasani.
Spine | 2009
Mehdi Sasani; Ali Fahir Ozer
Study Design. A prospective study was performed. Objective. To assess an unusual technique for corpectomy and expandable cage placement via single-stage posterior approach in acute thoracic or lumbar burst fractures. Summary and Background Data. Burst fractures represent 10% to 20% of all spine injuries at or near the thoracolumbar junction, and can cause neurologic complications and kyphotic deformity. The goal of surgical intervention is to decompress the neural elements, restore vertebral body height, correct angular deformity, and stabilize the columns of the spine. Methods. The study comprised 14 patients (8 women and 6 men aged 40.3 years) who had 1 spinal burst fracture between T8 and L4 and who underwent single-stage posterior corpectomy, circumferential reconstruction with expandable-cage placement, and transpedicle screwing between January 2003 and May 2005. Neurologic status was classified using the American Spinal Injury Association (ASIA) impairment scale and functional outcomes were analyzed using a visual analogue scale (VAS) for pain. The kyphotic angle (&agr;) and lordotic angle (&bgr;) were measured in the thoracic or thoracolumbar and lumbar regions, respectively. Results. The mean follow-up time was 24 months (range, 12–48 months). Neurologic status was in 7 patients (preop: ASIA-E, postop: unchanged), 2 patients (preop: ASIA-D, postop: 1 unchanged, 1 improved to ASIA-E), 3 patients (preop: ASIA-C, postop: 2 improved to ASIA-D, 1 improved to ASIA-E), 2 patients (preop: ASIA-B, postop: 1 improved to ASIA-C, 1 unchanged). The mean operative time was 187.8 minutes. The mean blood loss was 596.4 mL. Regarding postoperative complications, 1 patient experienced transient worsening of neurologic deficits and 1 patient developed pseudarthrosis. The mean preoperative VAS score was 8.21 and the mean postoperative VAS score was 2.66 (P < 0.05). The mean preoperative kyphotic angle for the 11 individuals with the thoracic or thoracolumbar burst fractures was 24.6° and the mean preoperative lordotic angle for the 3 individuals with lumbar burst fractures was 10.6°. The corresponding values at 12 months postsurgery were 17.1° and 13.6°. Conclusion. This single-stage posterior approach for acute thoracic and lumbar burst fractures offers some advantages over the classic combined anterior-posterior approach. The results from this small series suggest that a single-stage posterior approach should be considered in select cases.
Journal of Spinal Cord Medicine | 2009
Mehdi Sasani; Ali Fahir Ozer; Metin Vural; Ali Cetin Sarioglu
Abstract Background: Idiopathic spinal cord herniation (ISCH) is a rare cause of progressive myelopathy frequently present in Brown-Séquard syndrome. Preoperative diagnosis can be made with magnetic resonance imaging (MRI). Many surgical techniques have been applied by various authors and are usually reversible by surgical treatment. Methods: Case report and review of the literature. Findings: A 45-year-old woman with Brown-Sequard syndrome underwent thoracic MRI, which revealed transdural spinal cord herniation at T8 vertebral body level. During surgery the spinal cord was reduced and the ventral dural defect was restorated primarily and reinforced with a thin layer of subdermal fat. The dural defect was then closed with interrupted stitches. Results: Although neurologic status improved postoperatively, postsurgical MRI demonstrated swelling and abnormal T2-signal intensity in the reduced spinal cord. Review of the English language literature revealed 100 ISCH cases. Conclusions: ISCH is a rare clinical entity that should be considered in differential diagnosis of Brown-Séquard syndrome, especially among women in their fifth decade of life. Outcome for patients who initially had Brown-Séquard syndrome was significantly better than for patients who presented with spastic paralysis. Although progression of neurologic deficits can be very slow, reduction of the spinal cord and repair of the defect are crucial in stopping or reversing the deterioration.
Journal of Neurosurgery | 2009
Murat Cosar; Mehdi Sasani; Tunc Oktenoglu; Tuncay Kaner; Omur Ercelen; K. Cagri Kose; A. Fahir Özer
OBJECT Vertebroplasty is a well-known technique used to treat pain associated with vertebral compression fractures. Despite a success rate of up to 90% in different series, the procedure is often associated with major complications such as cord and root compression, epidural and subdural hematomas (SDHs), and pulmonary emboli, as well as other minor complications. In this study, the authors discuss the major complications of transpedicular vertebroplasty and their clinical implications during the postoperative course. METHODS Vertebroplasty was performed in 12 vertebrae of 7 patients. Five patients had osteoporotic compression fractures, 1 had tumoral compression fractures, and 1 had a traumatic fracture. Two patients had foraminal leakage, 1 had epidural leakage, 1 had subdural cement leakage, 2 had a spinal SDH, and the last had a split fracture after the procedure. RESULTS Three patients had paraparesis (2 had SDHs and 1 had epidural cement leakage), 3 had root symptoms, and 1 had lower back pain. Two of the 3 patients with paraparesis recovered after evacuation of the SDH and subdural cement; however, 1 patient with paraparesis did not recover after epidural cement leakage, despite cement evacuation. Two patients with foraminal leakage and 1 with subdural cement leakage had root symptoms and recovered after evacuation and conservative treatment. The patient with the split fracture had no neurological symptoms and recovered with conservative treatment. CONCLUSIONS Transpedicular vertebroplasty may have major complications, such as a spinal SDH and/or cement leakage into the epidural and subdural spaces, even when performed by experienced spinal surgeons. Early diagnosis with CT and intervention may prevent worsening of these complications.
Journal of Spinal Disorders & Techniques | 2007
Tunc Oktenoglu; Murat Cosar; Ali Fahir Ozer; Celal Iplikcioglu; Mehdi Sasani; Nazan Canbulat; Cengiz Bavbek; Ali Cetin Sarioglu
Background Anterior cervical microdiscectomy (ACD) is commonly applied in the surgical treatment of cervical disc herniation. However, following discectomy procedure to perform a fusion process is still controversial. Therefore, a controlled, multicentric, prospective, randomized study was designed. Material and Method Totally 20 patients were operated. Eleven patients were operated with applying simple anterior microdiscectomy technique. Nine patients were operated via ACD and fusion with a semirigid plate technique. Preoperative and postoperative [immediate; postoperative first day and postoperative 1 y (mean 13.95 mo)] computed tomography studies and plain x-rays were obtained. The cervical disc and bilateral neural foramen heights of the operated level and adjacent segments were calculated. Pain assessment was performed using visual analog pain scale. Mann-Whitney statistical analysis method was applied to compare the outcomes for both groups. Results Satisfactory result was achieved in both groups. The pain scores for major complaint (arm pain) were decreased significantly in all patients after surgery regardless of the type of technique applied. The improvement in neck pain scores was significant only in patients who were treated with fusion procedure. There were no significant changes in disc height and neural foramen height measurements for both groups in adjacent levels in immediate and 1-year postoperative periods. The patients who were operated with simple ACD technique showed no significant decrease at postoperative first day in disc height and neural foramen height. However, the 1-year postoperative radiologic studies showed a significant decrease in disc height and neural foramen dimensions compared with preoperative values. The patients who were treated with fusion process showed a significant increase in disc height and nonsignificant increase in neural foramen heights at immediate postoperative study. However, with time, all dimensions showed significant decrease compared with preoperative values. Conclusions ACD technique offers satisfactory outcome regardless of whether fusion process is applied or not. Fusion with semirigid plate offers an advantage at operated level in immediate postoperative period in regard of disc height and neural foramen height. However, semirigid anterior plates by definition do not stop subsidence and the advantage that is offered by this technique is not persistent. On the other hand, to apply fusion process with semirigid plate system offers significantly less narrowing in disc height compared with simple ACD technique.
The Open Orthopaedics Journal | 2010
Ali Fahir Ozer; Neil R. Crawford; Mehdi Sasani; Tunc Oktenoglu; Hakan Bozkus; Tuncay Kaner; Sabri Aydin
Background: A lumbar pedicular dynamic stabilization system (LPDSS) is an alternative to fusion for treatment of degenerative disc disease (DDD). In this study, clinical and radiological results of one LPDSS (Saphinaz, Medikon AS, Turkey) were compared with results of rigid fixation after two-year follow-up. Methods: All patients had anteroposterior and lateral standing x-rays of the lumbar spine preoperatively and at 3 months, 12 months and 24 months after surgery. Lordosis of the lumbar spine, segmental lordosis and ratio of the height of the intervertebral disc spaces (IVS) measured preoperatively and at 3 months, 12 months and 24 months after surgery. All patients underwent MRI and/or CT preoperatively, 3months, 12 months and 24 months postoperatively. The ratio of intervertebral disc space to vertebral body height (IVS) and segmental and lumbar lordosis were evaluated preoperatively and postoperatively. Pain scores were evaluated via Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) preoperatively and postoperatively. Results: In both groups, the VAS and ODI scores decreased significantly from preoperatively to postoperatively. There was no difference in the scores between groups except that a lower VAS and ODI scores were observed after 3 months in the LPDSS group. In both groups, the IVS ratio remained unchanged between preoperative and postoperative conditions. The lumbar and segmental lordotic angles decreased insignificantly to preoperative levels in the months following surgery. Conclusions: Patients with LPDSS had equivalent relief of pain and maintenance of sagittal balance to patients with standard rigid screw-rod fixation. LPDSS appears to be a good alternative to rigid fixation.
Orthopedics | 2010
Tuncay Kaner; Sedat Dalbayrak; Tunc Oktenoglu; Mehdi Sasani; Ahmet Levent Aydin; Ali Fahir Ozer
This article describes the clinical and radiological outcomes of a comparison of posterior dynamic transpedicular stabilization and posterior rigid transpedicular stabilization with fusion after decompression in the treatment of degenerative spondylolisthesis. This prospective clinical and radiologic study was conducted between 2004 and 2007 and included 46 patients, of whom 33 were women (71.7%) and 13 were men (28.3%). Mean patient age was 61.67+/-10.80 years (range, 45-89 years). Twenty-six patients who underwent lumbar decompression and posterior dynamic transpedicular stabilization were followed for a mean of 38 months (range, 24-55 months). In the fusion group, 20 patients who underwent lumbar decompression and rigid stabilization with fusion were followed for a mean of 44 months (range, 26-64 months). The intervertebral space measurements of the dynamic group at the preoperative examination and at 12 and 24 months postoperatively were statistically significantly higher than the intervertebral space measurements of the fusion group (P<.05). In the dynamic group, complications occurred in 2 patients; the first was a screw malposition, which was improved with revision surgery within 1 month of the initial surgery, and the second was a fusion performed in the second year in 1 patient because the patient reported continued pain. In the fusion group, adjacent segment disease was observed in 1 patient, with subsequent reoperation. Lumbar decompression and posterior dynamic transpedicular stabilization yield satisfactory results in the treatment of degenerative lumbar spondylolisthesis and can be considered a valid alternative to fusion.
Turkish Neurosurgery | 2009
Tuncay Kaner; Mehdi Sasani; Tunc Oktenoglu; Ali Fahir Ozer
Fusion surgeries are still the gold standard in the treatment of the degenerative spine. Spinal fusion has some problems, however. Adjacent segment disease, donor place ailment, and the morbidity of the surgery has emerged as important problems over the years. As a consequence of such complications after fusion, the search for an alternative treatment for the degenerative spine widened. While trying to maintain the motion in the joint, dynamic stabilization aims to remove the pain by distributing the weight between anterior and posterior elements of the spine. Various new devices have now been developed for the dynamic stabilization of the spine. In this report, the dynamic stabilization devices of the spine are classified anew and, the authors explain briefly the historical evolution process, specialties, indications and contraindications of these dynamic stabilization devices.
The Spine Journal | 2011
Ahmet Levent Aydin; Mehdi Sasani; Belgin Erhan; Hadi Sasani; Seda Özcan; Ali Fahir Ozer
BACKGROUND CONTEXT Idiopathic spinal cord herniation (ISCH) is a rare cause of progressive myelopathy. Preoperative diagnosis can be made with magnetic resonance imaging (MRI). Many surgical techniques have been applied by various authors, and ISCH is usually reversible by surgical treatment. PURPOSE To present a case of ISCH in two separate zones at two thoracic levels. To our knowledge, this is the first such case to be published in English literature. We also discuss the clinical findings, surgical procedures, and surgical outcomes for other previously reported cases of ISCH in the literature. STUDY DESIGN Case report. METHODS A 52-year-old woman with bilateral lower extremity weakness underwent thoracic MRI, which revealed transdural spinal cord herniation at two separate zones, namely, the T4-T5 and T5-T6 intervertebral disc levels. RESULTS During surgery, the spinal cord was reduced, the two separate dural defects were connected, and the new single defect was restored then reinforced with a thin layer of fascial graft. The posterior dural defect was then closed with interrupted stitches. The patients neurologic status was characterized by no changing of the preoperative motor status. Follow-up MRI scans showed that the cord was replaced in the dural sac and showed cord hyperintensity in the herniation levels. The patient could move with a cane at the sixth month postoperatively. CONCLUSIONS Idiopathic spinal cord herniation is a rare clinical condition that should be considered in the differential diagnosis of paraplegia. Although progression of neurologic deficits can be very slow, reduction of the spinal cord and repair of the defect are crucial to stop or reverse the deterioration. The outcome for patients who initially have Brown-Séquard syndrome is significantly better than for patients who presented with spastic paralysis. To our knowledge, this case study represents the first reported instance in which two separate anterior dural defects caused two levels of anterior spinal cord herniation.
Journal of Korean Neurosurgical Society | 2010
Tuncay Kaner; Mehdi Sasani; Tunc Oktenoglu; Bilgehan Solmaz; Ali Cetin Sarloglu; Ali Fahir Ozer
OBJECTIVE To evaluate the clinical results of gross total resection in the surgical approach to spinal ependymoma. METHODS Between June 1995 and May 2009, 13 males and 8 females (mean age 34) diagnosed with intramedullary or extramedullary spinal ependymoma were surgically treated at our centre. The neurological and functional state of each patient were evaluated according to the modified McCormick scale. RESULTS The average follow-up duration was 54 months (ranging from 12 to 168 months). The locations of the lesions were: thoracic region (4, 19%), lumbar region (7, 34%), cervical region (4, 19%), cervicothoracic region (3, 14%) and conus medullaris (3, 14%). Four patients (19%) had deterioration of neurological function in the early postoperative period. The neurological function of three patients was completely recovered at the 6th postoperative month, while that of another patient was recovered at the 14th month. In the last assessment of neurological function, 20 patients (95%) were assessed as McCormick grade 1. No perioperative complications developed in any of our patients. In one patients 24-month assessment, tumour recurrence was observed. Re-operation was not performed and the patient was taken under observation. CONCLUSION Two determinants of good clinical results after spinal ependymoma surgery are a gross total resection of the tumour and a good neurological condition before the operation. Although neurological deficits in the early postoperative period can develop as a result of gross total tumour resection, significant improvement is observed six months after the operation.
Pediatric Neurosurgery | 2008
Mehdi Sasani; Bahloul Asghari; Yalda Asghari; Ruya Afsharian; Ali Fahir Ozer
Spinal dysraphism is characterized by a lack of fusion of the vertebral arches that occurs in the absence of spinous processes with variable amounts of lamina. Here, we retrospectively present the importance of cutaneous lesions and their correlation with clinical presentation, radiological examination and urodynamic assessment. We retrospectively reviewed 612 (6.12%) cases with skin lesions from 10,000 consecutive live-born children seen at two institutions between January 1998 and March 2005. We divided all children into a control group and three groups based on clinical assessment, radiological examination and urodynamic evaluation results. Neurological deficits were identified in 113 (18.46%) children, while spinal dysraphism disorders, tethered cord syndrome and associated orthopedic malformations were found in 171 (27.94%), 119 (19.45%) and 28 (4.57%) patients, respectively. The incidence of tethered cord with lumbosacral dimple lesions over the sacrum (32/119, 26.65% of patients) was 3.5-fold higher than that of lesions found over the coccyx (9/119, 7.5% of patients). Uroneurological symptoms were found in 207/612 (33.82%) children. Urodynamic assessment revealed decreased bladder capacity in 10% of patients, detrusor hyperflexia during filling in 47% and a low-compliance detrusor in 71%. Discordance between ultra- sonography and MRI was found in 16.58% of patients. Spinal cord untethering was performed for 109 patients. Nearly all children with resolution were at the end of their follow-up period (24 months). Retethering occurred in 21 (19.26%) patients, and a second untethering surgery was performed in 12 patients. When spina bifida was associated with lumbar skin lesions, there may have been an increased incidence of tethered cord and other spinal cord disorders. MRI scans are more reliable and give an exact diagnosis of tethered cord. Neurological and uroneurological instability are ultimately a clinical diagnosis, and there is controversy about their indications for surgery. However, the correlation between urodynamic assessment and cutaneous lesions with a tethered cord found by MRI examination allow for an early diagnosis and the possibility of prompt treatment.