Gamma Knife radiosurgery for the treatment of trigeminal neuralgia: A single center-experience.

INTRODUCTION AND OBJECTIVES: We aimed to assess the outcomes of patients with trigeminal neuralgia (TGN) who underwent Gamma Knife radiosurgery (GKRS). MATERIALS AND METHODS: Fifty-three patients with typical TGN underwent GKRS from May 2012 until December 2022. Among these patients, 45 patients who were follow-up for at least 12 months were included in the study. A mean dose of 87.5 Gy (range, 80-90) was administered to the trigeminal nerve. Postoperatively, outcome was considered excellent if the patient was pain- and medication-free. RESULTS: The mean symtpom duration was 9.53 years, and the mean patient age was 59.8 years (range, 34-85). The mean follow-up period was 46.8 months (range, 12-127 months). 46.7% of patients had a history of previous surgical interventions. A single nerve division was affected in 14 patients (31.1%), and multiple divisions were affected in 31 patients (68.9%). The rate of initial pain relief was 80%. Hypoesthesia in the area of trigeminal nerve developed in 30 (66.7%). Twenty patients (44.4%) exhibited excellent results within 72.4 months. Recurrence occurred in 11 patients (24.4%) with 27.6 months. CONCLUSIONS: Our results suggest that GKRS is a safe and effective procedure. Thus, it is an attractive first- and second-line treatment choice for TGN.

Cement Augmented Pedicle Screw Instrumentation in Pediatric Spine Surgery.

BACKGROUND: Osteoporosis in pediatric patients is rare. Osteomalacia and osteoporosis are known to develop in syndromic or neuromuscular scoliosis children. Spinal deformity surgery for pediatric patients with osteoporosis is challenging, associated with pedicle screw (PS) failure and compression fractures. Cement augmentation of PS is one several measures to prevent screw failure. It provides additional pull-out strength to the PS in the osteoporotic vertebra. METHODS: In 2010-2020, an analysis of pediatric patients who had cement augmentation of PS with a minimum follow-up of 2 years was performed. Radiological and clinical evaluations were analyzed. RESULTS: The study included 7 patients (4 girls, 3 boys) with a mean age of 13 years (range, 10-14 years) and mean follow-up of 3 years (range, 2-3 years). Only 2 patients underwent revision surgery. Total number of cement augmented PSs was 52 with an average of 7 per patient. Only 1 patient had lower instrumented vertebra vertebroplasty. There was no PS pull-out in the cement augmented levels, and there were no neurological deficits or pulmonary cement embolisms. One patient developed a PS pull-out in uncemented levels. Two patients developed compression fractures, one, with osteogenesis imperfecta, in the supra-adjacent levels (upper instrumented vertebra + 1 and upper instrumented vertebra + 2), and the other, with neuromuscular scoliosis, in the uncemented segments. CONCLUSIONS: In this study, all cement augmented PSs provided satisfactory radiological outcomes without PS pull-out and adjacent vertebral compression fracture. In pediatric spine surgery, in osteoporotic patients with a poor bone purchase, cement augmentation may be used, especially in high-risk patients with osteogenesis imperfecta, neuromuscular scoliosis, and syndromic scoliosis.

Transdiscal Screw Fixation in L5-S1 Adult Spondylolisthesis: Technical Note and Midterm Outcomes of a Case Series.

BACKGROUND: Spondylolisthesis changes the pelvic morphology and sagittal spinopelvic alignment with abnormality compared to individuals with similar pelvic morphology. There are many treatment options including a combination of decompression and fusion. In spondylolisthesis patients with high-grade spondylolisthesis, bone to bone contact (closed intradiscal space), and high-grade disc degeneration with disc collapse, fusion is challenging. METHODS: From 2011 through 2020, an analysis of L5-S1 spondylolisthesis patients who had L5-S1 transdiscal screw fixation with a minimum follow-up of 2 years was performed. Radiological evaluation and clinical measures were compared preoperatively and postoperatively. Postoperative complications were analyzed. Also, L5-S1 degree fusion was analyzed using a computed tomography scan. RESULTS: Eight patients of L5-S1 spondylolisthesis with a mean follow-up of 69 (25-122) months. All patients were female; the average age was 58 (43-78) years. 4 patients presented with high-grade spondylolisthesis (Meyerding grade III). Among the patients, 3 patients were undergoing revision surgery. Only 5 patients had interbody fusion for their adjacent levels. In the postoperative follow-up, none of the patients had neurological deficits. Radiological evaluations of L5-S1 level showed fusion in all patients. Only 1 patient had rod failure and was advised for revision surgery. CONCLUSIONS: L5-S1 transdiscal screw fixation may provide a satisfactory rigid fixation and fusion at the L5-S1 level in cases of spondylolisthesis. This technique requires a surgeon's experience. Despite the challenge of this technique, it can provide a safe option for acquiring rigid stabilization.

Segmental Zoster Paresis of the Unilateral Lower Extremity With Neuritis MRI Findings: A Case Report and Literature Review.

Herpes zoster (HZ) is a common clinical condition caused by the reactivation of the latent varicella-zoster virus (VZV). Neurological complications after HZ have been described, including a rare condition of segmental zoster paresis (SZP), which results in unilateral motor impairment in the extremities. Only two cases of HZ patients with radiculopathy and MRI findings of neuritis have been reported. We present a 62-year-old male with a HZ rash in the right calf and low back pain radiating to the right leg accompanied by a right leg great toe weakness for one week. Neurological examination revealed 4/5 dorsiflexion of the right great toe. Also, the patient's rash was distributed on the L5 dermatome. The lumbar MRI showed a contrast enhancement of the right L5 nerve root with enlargement diagnosed as neuritis. The patient was treated with valacyclovir. The neuromotor deficit and the cutaneous rash started to improve on the third day of treatment. This case emphasizes the necessity of considering SZP in the differential diagnosis of elderly patients presenting with muscle weakness in the lower extremity with or without a rash. MRI evaluations of HZ patients with radiculopathy may include contrast-enhanced sequences.

Anterior-to-Posterior Epidural Migration of a Lumbar Disc Herniation at L1-L2: A Case Report.

Protruded disc fragments that penetrate the posterior longitudinal ligament (PLL) migrate rostral or caudal in the vertical plane, some laterally in the horizontal plane, or into the foramina involving the anterior aspect of the spinal canal. Often, there is migration to the ventral epidural space. However, posterior epidural migration of a lumbar disc herniation (PEMLDH) is a rare phenomenon that makes the differential diagnosis challenging. We describe a rare case of anterior-to-posterior epidural migration of a lumbar disc herniation at the L1-L2 level. It was treated microsurgically after total laminectomy, and total resection of the lesion was carried out. PEMLDH is a unique condition causing neurological deficits at different levels. Due to different localization of disc herniations, optimal diagnosis becomes critical for determining the timing and type of treatment surgically.

The Importance of Lumbar Curve Flexibility and Apical Vertebral Rotation for the Prediction of Spontaneous Lumbar Curve Correction in Selective Thoracic Fusion for Lenke Type 1 and 2 C Curves: Retrospective Cohort Study with a Mean Follow-Up of More than 10 years.

STUDY DESIGN: Retrospective analysis of a prospectively collected data. OBJECTIVE: Lumbar flexibility(LF) is generally defined with preoperative side bending films;it is not clear what percentage of LF predicts the spontaneous lumbar curve correction (SLCC) at long term follow up. Aim of this study was to find out cut-off value of preoperative LF,apical vertebra rotation(AVR) and apical vertebral translation(AVT);which may predict more than 50%SLCC. METHODS: Patients with Lenke 1C&2C curves,treated with posterior STF,with a minimum 10 years follow up were included.The patients who had more than 50% SLCC(Group A) or less than 50% (Group B) were compared in terms of LF,AVR and AVT to understand a cut-off value of those parameters.Statistically, Receiver Operating Characteristic(ROC) test was used. RESULTS: Fifty five AIS patients (54F, 1M) with mean age 14 (11-17) were included to study.Thoracic curve correction rate was 75%;lumbar curve correction rate was 59% at the latest follow up.Group A included 45(82%) patients at the latest follow up.Three patients (5%) showed coronal decompensation at early postop and 2 of them became compensated at f/up.ROC analyses showed 69% flexibility as the cut-off value for SLCC (P < .01).The difference between groups in terms of preop mean AVRs was significant (P = .029) (Group A = 1.9; Group B = 2.4). CONCLUSION: In Lenke 1C&2C curves,whenever LF on the preoperative bending x-ray is greater than 70% (P < .01)and AVR is equal or less than grade 2,STF provides satisfactory clinical and radiological SLCC with more than mean 10 years f/up.This flexibility rate and apical vertebral rotation can be helpful in decision making for successful STF.

Single-Stage Posterior Vertebral Column Resection With Circumferential Reconstruction for Thoracic/Thoracolumbar Burst Fractures With or Without Neurological Deficit: Clinical Neurological and Radiological Outcomes.

STUDY DESIGN: Retrospective study. OBJECTIVE: The aim of this study is to evaluate the clinical, neurological, and radiological outcomes of posterior vertebral column resection (PVCR) technique for treatment of thoracic and thoracolumbar burst fractures. METHODS: Fifty-one patients (18 male, 33 female) with thoracic/thoracolumbar burst fractures who had been treated with PVCR technique were retrospectively reviewed. Preoperative and most recent radiographs were evaluated and local kyphosis angle (LKA), sagittal and coronal spinal parameters were measured. Neurological and functional results were assessed by the American Spinal Injury Association (ASIA) Impairment Scale, visual analogue scale score, Oswestry Disability Index, and Short Form 36 version 2. RESULTS: The mean age was 49 years (range 22-83 years). The mean follow-up period was 69 months (range 28-216 months). Fractures were thoracic in 16 and thoracolumbar in 35 of the patients. AO spine thoracolumbar injury morphological types were as follows: 1 type A3, 15 type A4, 4 type B1, 23 type B2, 8 type C injuries. PVCR was performed in a single level in 48 of the patients and in 2 levels in 3 patients. The mean operative time was 434 minutes (range 270-530 minutes) and mean intraoperative blood loss was 520 mL (range 360-1100 mL). The mean LKA improved from 34.7° to 4.9° (85.9%). For 27 patients, the initial neurological deficit (ASIA A in 8, ASIA B in 3, ASIA C in 5, and ASIA D in 11) improved at least 1 ASIA grade (1-3 grades) in 22 patients (81.5%). Solid fusion, assessed with computed tomography at the final follow-up, was achieved in all patients. CONCLUSION: Single-stage PVCR provides complete spinal canal decompression, ideal kyphosis correction with gradual lengthening of anterior column together with sequential posterior column compression. Anterior column support, avoidance of the morbidity of anterior approach and improvement of neurological deficit are the other advantages of the single stage PVCR technique in patients with thoracic/thoracolumbar burst fractures.

Clinical, radiological and HRQoL outcomes after selective thoracic fusion with minimum 15-year follow-up.

INTRODUCTION: The purpose of the study was to provide a 15-year natural history evaluation of the radiographic appearance of uninstrumented compensatory lumbar curves in patients who had undergone selective thoracic fusion (STF) for scoliosis, measure any changes in health-related quality of life scores (HRQoL) and compare them with controls matched for age, gender and body-mass index (BMI). METHODS: STF group included 43 female adolescent idiopathic scoliosis (AIS) patients who underwent STF with mean age 33(27-42) years and a mean follow-up of 18.7 (15-28) years, mean BMI 22(18-29). Preop, early postop and follow-up radiographs were reviewed for behavior of lumbar curves. Control group included a random selection of healthy volunteers with no history of back pain and with mean age 33(27-41), and mean BMI 22(17-33). HRQoL scores were compared between two groups in latest f/up. Radiographs including low dose biplanar imaging with EOS were used to measure disc heights and assess for radiographic evidence of degenerative changes. Various parameters were statistically compared. RESULTS: Posterior fusion was performed in all 43, with all pedicle screws used in 41 and all-hook constructs in 2. Main thoracic curve correction was improved from pre-op to early-post-op and maintained at latest f/up (55.6°-16.1°-16.9°). Spontaneous lumbar curve correction (SLCC) was also maintained beyond 15 years (39.9°-16.6°-17.1°). Two patients developed coronal decompensation following surgery, but improved with time and were well compensated at final follow-up. Mean HRQoL scores, self-image and mental health scores were higher in STF group than control group (p < 0.05). SRS-22r pain and function, Oswestry Disability Index and Numeric Rating Scale, marital status, number of children were similar between the groups(p > 0.05). All disc heights except L5-S1 were significantly lower in STF group (p < 0.05). There was no significant difference between the groups for degenerative changes in the latest radiographs. CONCLUSION: In this group of patients, the uninstrumented lumbar curve spontaneously corrected and the correction was maintained after 18 years following surgery using STF. Mild degenerative changes were seen radiographically and HRQoL scores suggest that the psychological-functional well-being are quite good in the long term in AIS patients who have undergone STF when compared with an age-gender-BMI-matched population.

Pulmonary cement embolism following cement-augmented fenestrated pedicle screw fixation in adult spinal deformity patients with severe osteoporosis (analysis of 2978 fenestrated screws).

INTRODUCTION: There is very limited information about pulmonary cement embolism (PCE) following cement-augmented fenestrated pedicle screw (CAFPS) fixation in the literature. The aim of this study to report the incidence of PCE following CAFPS fixation in adult deformity patients with severe osteoporosis and to identify risk factors such as; the number of levels, number of screws, and the cement volume used. METHODS: 281 patients (204F, 77M) in whom CAFPS fixation was used during deformity surgery were included. All patients' routine postop 2 day chest X-rays and any available CT scans were reviewed by two radiologists. In patients with PCE, preop, early postop, and latest echocardiography studies were compared in terms of changes in pulmonary artery pressure (PAP) and right ventricular dilatation. Estimated cement volume used was calculated as: 2 cc (1 cc + 1 cc) per thoracic and 3 cc (1.5 cc + 1.5 cc) per lumbar levels, which are our routine protocol. Statistical analysis for risk factors was assessed with point biserial correlation test. RESULTS: Average age is 70.5 (51-89) and average follow-up is 3.2 years (2-5). A total of 2978 CAFPS were instrumented with a mean of 10.5 levels (2-16) in 281 patients. PCE was diagnosed radiologically in 46 patients (16.3%). Among these 46 patients, PCE was clinically symptomatic in only 4 patients. Overall incidence of symptomatic PCE was 1.4% (4 of 281). Symptomatic PCE was statistically significant: when CAFPS fixation was performed > 7 levels; > 14 screws were used, and > 20-25 cc cement was used for augmentation (r = 0.378). In PCE group, mean preop PAP values of 27.40 (20-37) mm/Hg increased to 32.34 (20-50) mm/Hg in early postop and decreased to 28.29 (18-49) mm/Hg at final follow-up. In symptomatic PCE patients, mean preop PAP values of 30.75 (28-36) mm/Hg increased to 45.74 (40-50) mm/Hg in early postop and decreased to 38.75 (37-40) mm/Hg at final follow-up. CONCLUSION: This study showed an overall 16.3% radiological PCE and 1.4% symptomatic PCE incidence when CAFPS were used due to severe osteoporosis. The symptomatic PCE risk was significant when CAFPS were > 7 levels; > 14 fenestrated screws; and > 20-25 cc cement volume is used and this may cause PAP increase and right ventricular dilatation.

Cervicothoracic spine duplication: a 10-year follow up of a neurological intact boy.

PURPOSE: Spine duplication is a very rare condition with the literature being composed of only case reports. All previously reported cases were thoracolumbar spine duplications. Here, we report cervicothoracic spine duplication in a neurological intact male. According to our knowledge, it is the first case in the literature of cervicothoracic spine duplication. CLINICAL PRESENTATION: A 3-year-old patient presented to a primary physician with a complaint of short stature. He was referred to our department with suspected spinal deformity. Computerized tomography imaging revealed anterior bony structure duplication and posterior dysmorphic elements at the C5-T9 levels. Magnetic resonance imaging revealed a syrinx cavity which splits cord at the duplication level and the relation of the syrinx with posterior mediastinum through anterior bone defect. He was followed up for 10 years. CONCLUSION: In the literature, spine duplication has been classified as a severe form of split cord malformation because of the concurrence of bone duplication with split spinal cord malformation (SCM). This case presents a distinct form of SCM which shows non-duplicated dural tube as unclassified and cervicothoracic duplication level without neurological deficitis. Treatment of SCM was based on removal of splitting fibrous/osseous process. Neurologic intact spine duplication could be followed up without surgical intervention.

Paper #21: Posterior Vertebral Column Resection (PVCR) for Congenital Thoracic Lordoscoliosis in children under age of 10 with minimum 5 years follow-up.

Congenital thoracic lordosis or lordoscoliosis are rare deformities which causes severe cardiopulmonary problems in early ages. PVCR is effective in restoring thoracal kyphosis in treatment of these rare deformities and avoids morbidity of combined surgeries.

Does It Make a Difference to Stop Fusion at L3 Versus L4 in Terms of Disc and Facet Joint Degeneration: An MRI Study With Minimum 5 Years Follow-up.

OBJECTIVES: To compare the functional outcomes of patients with idiopathic scoliosis who had surgical correction and fusion with all pedicle screw construct down to L3 or L4 and to evaluate whether saving a mobile lumbar motion segment distally would demonstrate any difference in terms of disc degeneration (DD) and facet joint degeneration (FJD) after minimum 5 years follow-up. SUMMARY OF BACKGROUND DATA: Selection of lowest instrumented vertebra (LIV) is often difficult when lumbar curve was included into the fusion (L3 vs L4). Saving L4 is believed to be beneficial for preserving motion and preventing degeneration of unfused lumbar spine. METHODS: The L3 group included 21 patients (mean age of 21.4) and L4 group included 16 patients (mean age 22.9). Control group included 30 healthy individuals with no spinal deformities (mean age of 23.8). Follow-up lumbar magnetic resonance images (MRIs) were evaluated for each patient in terms of DD and FJD. Clinical evaluation was done by using the Scoliosis Research Society-22r, Oswestry Disability Index, and Numeric Rating Scale. RESULTS: Mean follow-up period was 7.4 (5-10) years in the L3 group and 9 (5-17) years in L4 group. Average correction rates for lumbar curve magnitudes were 78% in the L3 group and 79% in the L4 group, with no significant correction loss at the final follow-up. There was no statistical difference for DD in all groups (p > .05). FJD was significantly greater in both L3 and L4 groups compared to the control group (p < .001). Clinical outcome scores were similar among all three groups (p > .05). CONCLUSION: Spinal balance and corrections remained stable, without showing any decompensation over time. This midterm MRI study demonstrated similar disc and facet degeneration rates for L3 and L4 groups. FJD at the upper two levels adjacent to the LIV was significant for both surgically treated groups. Clinical outcome scores were similar for all groups at minimum 5 years follow-up.

Does pedicle screw fixation under age 5 cause spinal canal narrowing? A CT study with minimum 5 years follow-up.

PURPOSE: The aim of this retrospective study was to evaluate the changes in the vertebral body and spinal canal area in a group of patients who had pedicle screw fixation under age 5 for the treatment of congenital spinal deformity at least 5 year follow-up. METHODS: 11 patients who had been operated due to spinal deformity under age 5 with who had a CT examination at least 5 years after the initial operation were included in the study. All patients underwent hemivertebrectomy and transpedicular fixation procedures at an average age of 3.18 years (range 2-5 years). All had preoperative CT to evaluate the congenital deformities. Measurements were done at the instrumented vertebrae as well as the un-instrumented ones above and below them to evaluate; vertebral body parameters, pedicle parameters and spinal canal area of upper instrumented vertebra (UIV), lower instrumented vertebra (LIV), upper adjacent un-instrumented vertebra and lower adjacent un-instrumented vertebra. RESULTS: The average follow-up was 7.2 (range 5-12) years. Six of the patients were over age 10 during the final CT examination while 5 were at age 7. Female-to male ratio was 8-3. Measurement of all the parameters in 22 instrumented and 22 non-instrumented segments showed a proportional increase rather than a decrease at each segment. The percentage of canal area growth at UIV and LIV was 21 and 17.5 %, respectively. CONCLUSION: Pedicle screw instrumentation has no adverse effect on further spinal body, pedicle and canal growth and does not result in iatrogenic spinal canal stenosis.

Selective Thoracic Fusion Provides Similar Health-Related Quality of Life but Can Cause More Lumbar Disc and Facet Joint Degeneration: A Comparison of Adolescent Idiopathic Scoliosis Patients With Normal Population 10 Years After Surgery.

OBJECTIVES: To evaluate the long-term behavior of the lumbar curve in patients with adolescent idiopathic scoliosis treated with selective thoracic fusion and to assess the clinical and radiologic outcomes in this fusion group compared with an age- and gender-matched group. SUMMARY OF BACKGROUND DATA: Selective thoracic fusion for the treatment of adolescent idiopathic scoliosis (AIS) preserves lumbar motion segments but leaves a residual deformity. By avoiding fusion of the lumbar spine, a greater mobility may be preserved, which may be an advantage in long-term follow-up in terms of degenerative changes in unfused segments. METHODS: Group A included 25 AIS patients with mean a age of 23.8 years and a mean 11.4 years of follow-up. Group B included 30 age- and gender-matched subjects without any deformity. Preoperative, postoperative, and follow-up radiographs were reviewed. All patients had MRIs taken at the final follow-up in order to evaluate disc degeneration (DD) and facet joint degeneration (FJD) at the unfused lumbar spine. Clinical evaluation was done by using Scoliosis Research Society-22R, Oswestry Disability Index, and numerical rating scale. RESULTS: Sagittal and coronal balance and lowest instrumented vertebra disc angulation were stable over time. Mean grading of lumbar DD was 2.16 (2-4) in Group A and 1.86 (1-3) in Group B. Lumbar FJDs were 2.05 (1-4) in Group A and 1.60 (1-3) in Group B. There was significant difference between the two groups for DD except for the L4-L5 level (p = .26). FJD was significantly higher in the L1-L2 and L2-L3 levels (L1-L2, p = .002, L2-L3, p = .002) but not for the other levels. Outcome scores were similar without significant differences between the two groups (p > .05). CONCLUSION: Selective thoracic fusion provides satisfactory outcomes at more than 10 years of follow-up. Our study demonstrated a moderate increase in the rate of disc degeneration in the unfused segments. Facet joint degeneration was significant at the upper two levels adjacent to the lowest instrumented vertebra.

Short-term X-ray results of posterior vertebral column resection in severe congenital kyphosis, scoliosis, and kyphoscoliosis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To analyze the efficacy and safety of posterior vertebral column resection performed on a consecutive series of patients with severe congenital spinal deformity. SUMMARY OF BACKGROUND DATA: The treatment of severe congenital spinal deformities is a demanding and difficult surgical challenge. Conventional procedures, such as posterior and anterior instrumentation or combined anteroposterior instrumentation provide limited correction in rigid neglected or maltreated (fused) deformities. METHODS: Forty-four patients with severe deformity and managed by posterior vertebral column resection between years 1997 and 2007 having more than 2 years of follow-up were included. Mean age was 8 (range, 2-28) years at the time of operation. The hospital charts were reviewed for demographic data and etiology of deformity. Measurements of curve magnitude and balance were made on 36-in. standing anteroposterior and lateral radiographs obtained before surgery and at most recent follow-up to assess deformity correction, spinal balance, complications related to the instrumentation, and any evidence of pseudarthrosis. RESULTS: Preoperative coronal plane major curve of 106° (range, 90°-132°) with flexibility of less than 30% was corrected to 41.4° (range, 20°-72°), showing a 61% scoliosis correction at the final follow-up. Coronal imbalance was improved by 79% at the most recent follow-up assessment. Preoperative thoracic kyphosis of 87° (range, 67°-103°) in patients with kyphosis was corrected to 36° (range, 25°-48°) at the most recent follow-up evaluation. Lumbar lordosis of 27° (range, 8°-35°) in patients with hypolordotic deformity was corrected to 45°. Complications included postoperative infection in 2 patients, dural laceration in 2 patients, and hemopneumothorax in 1 patient. CONCLUSION: Posterior vertebral column resection is an effective technique providing a successful correction of stiff complex congenital deformities. However, it is a technically demanding procedure, with possible risks for major complications.

The role of DTI in early detection of cervical spondylotic myelopathy: a preliminary study with 3-T MRI.

INTRODUCTION: The radiological diagnosis of cervical spondylotic myelopathy (CSM) has to be made as soon as possible, since surgery performed in earlier stages during the course of CSM was reported to be more successful when compared with later stages. We hypothesized that diffusion tensor imaging (DTI) may detect CSM in earlier stages, before the appearance of signal increase in T2-weighted sequences. METHODS: A total of 16 patients with neurological signs and symptoms of CSM but without hyperintensity in spinal cord on T2-weighted sequences enrolled in the study. The magnetic resonance (MR) examinations were performed on a 3-T MR imaging system. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were generated on axial plane. The ADC and FA measurements in each individual were made at the level of most severe cervical canal stenosis and at a nonstenotic level. Student's t test was used to compare FA and ADC values of the spinal cord in stenotic and nonstenotic segments. We also investigated if there was a correlation between DTI parametrics and duration of clinical symptoms by using Pearson correlation analysis. RESULTS: All patients showed changes in DTI parametrics at stenotic segments. While FA values of the spinal cord at the stenotic level showed a statistically significant reduction, there was a statistically significant increase in the measured ADC values (p < 0.001). There was no statistical correlation between the duration of symptoms and DTI parametrics. CONCLUSION: Our preliminary findings indicate that DTI may show abnormalities in the spinal cord before the development of T2 hyperintensity on conventional sequences in patients with CSM.

The role of routine magnetic resonance imaging in the preoperative evaluation of adolescent idiopathic scoliosis.

The routine use of magnetic resonance imaging (MRI) in adolescent idiopathic scoliosis remains controversial, and current indications for MRI in idiopathic scoliosis vary from study to study. The purpose of this study was to demonstrate the prevalence of neural axis malformations and the clinical relevance of routine MRI studies in the evaluation of patients with adolescent idiopathic scoliosis undergoing surgical intervention without any neurological findings. A total of 249 patients with a diagnosis of idiopathic scoliosis were treated surgically between the years 2002 and 2007. A routine whole spine MRI analysis was performed in all patients. On the preoperative clinical examination, all patients were neurologically intact. There were 20 (8%) patients (3 males and 17 females) who had neural axis abnormalities on MRI. Three of those 20 patients needed additional neurosurgical procedures before corrective surgery; the remaining underwent corrective spinal surgery without any neurosurgical operations. Magnetic resonance imaging may be beneficial for patients with presumed idiopathic scoliosis even in the absence of neurological findings and it is ideally performed from the level of the brainstem to the sacrum.

Destructive stereotactic surgery for treatment of dystonia.

BACKGROUND: This study is a retrospective review of the results of stereotactic destructive surgery in selected cases of drug-resistant dystonia. METHODS: Fifty-eight patients with drug-resistant dystonia were treated with stereotactic surgery between 1991 and 1999 in our institution. These patients' charts were retrospectively analyzed. The timing of the conducted evaluations was as follows: preoperatively, postoperatively, in the postoperative 1st week, 6th month, 12th month, and also thereafter every year. RESULTS: Symptoms of dystonia occurred before the age of 10 years in 30 patients (51.8%) and after the age of 10 years in 28 patients (48.2%). Generalized dystonia was detected in 41 patients, whereas 11 patients had hemidystonia, 5 patients had focal dystonia, and 1 patient had segmental dystonia. The most common etiologic factor was CP (n = 34). A total of 103 ablative lesions were created in 86 surgical sessions. Thalamotomy, pallidotomy, subthalamotomy, and the region of Forel lesions were performed either separately or in combination. In this series, the mean follow-up time was 102.2 months. Except for 2 cases of temporary hemiparesis, no other complications were observed. Minor improvement was obtained in 17 patients (19.7%), improvement of a medium degree was obtained in 17 patients (19.7%), high-degree improvement was obtained in 11 (12.8%), and very high degree improvement was obtained in 16 (18.6%) patients. A final evaluation revealed permanent improvement in 32 patients (55.2%). CONCLUSION: Production of stereotactic destructive lesions in certain specified targets is a safe method that improves quality of life and aids ambulation in patients with dystonia resistant to medical therapy.

Accuracy and diagnostic yield of stereotactic biopsy in the diagnosis of brain masses: comparison of results of biopsy and resected surgical specimens.

The aim of this retrospective study was to investigate the diagnostic yield and accuracy of stereotactic biopsy in patients harboring brain mass. Stereotactic biopsy was performed in 130 patients between 1995 and 2000 in an educational and research hospital in Turkey. The results of histological analysis were compared to the resected specimens in 23 patients. The lesions were lobar in 62% of cases and deep-seated in 38% of cases. During the biopsy procedures, the pathologist was in the operating theatre and a very small fragment was used for cytological examination. No frozen section was used in any of the cases. Samples were diagnostic in 122 cases. The overall diagnostic yield of the procedure was 94%. A definitive histological diagnosis was not made in eight patients. The histological diagnoses of the two procedures were identical (complete agreement) in 16 cases. In three cases, the histological diagnoses between the two procedures were slightly different without impact on patient care (minor disagreement). The diagnosis of the stereotactic biopsy was completely changed after craniotomy in four cases (major disagreement). The accuracy of the histological diagnosis was 83%. There was only one major complication, which involved intracerebral hemorrhage. Despite the limited number of patients who underwent resection, our data suggest that stereotactic biopsy of brain masses is a safe and accurate technique that can obtain adequate tissue for histological diagnosis, thus providing the best avaible treatment for patients. Cytological evaluation of the streotactic biopsy also is a highly effective tool for obtaining sufficient material during the procedure in many cases.