Effectiveness of an Annular Closure Device to Prevent Recurrent Lumbar Disc Herniation: A Secondary Analysis With 5 Years of Follow-up.

Importance: Patients with large annular defects following lumbar microdiscectomy for disc herniation are at increased risk for symptomatic recurrence and reoperation. Objective: To determine whether a bone-anchored annular closure device in addition to lumbar microdiscectomy resulted in lower reherniation and reoperation rates vs lumbar microdiscectomy alone. Design, Setting, and Participants: This secondary analysis of a multicenter randomized clinical trial reports 5-year follow-up for enrolled patients between December 2010 and October 2014 at 21 clinical sites. Patients in this study had a large annular defect (6-10 mm width) following lumbar microdiscectomy for treatment of lumbar disc herniation. Statistical analysis was performed from November to December 2020. Interventions: Lumbar microdiscectomy with additional bone-anchored annular closure device (device group) or lumbar microdiscectomy only (control group). Main Outcomes and Measures: The incidence of symptomatic reherniation, reoperation, and adverse events as well as changes in leg pain, Oswestry Disability Index, and health-related quality of life when comparing the device and control groups over 5 years of follow-up. Results: Among 554 randomized participants (mean [SD] age: 43 [11] years; 327 [59%] were men), 550 were included in the modified intent-to-treat efficacy population (device group: n = 272; 270 [99%] were White); control group: n = 278; 273 [98%] were White) and 550 were included in the as-treated safety population (device group: n = 267; control group: n = 283). The risk of symptomatic reherniation (18.8% [SE, 2.5%] vs 31.6% [SE, 2.9%]; P < .001) and reoperation (16.0% [SE, 2.3%] vs 22.6% [SE, 2.6%]; P = .03) was lower in the device group. There were 53 reoperations in 40 patients in the device group and 82 reoperations in 58 patients in the control group. Scores for leg pain severity, Oswestry Disability Index, and health-related quality of life significantly improved over 5 years of follow-up with no clinically relevant differences between groups. The frequency of serious adverse events was comparable between the treatment groups. Serious adverse events associated with the device or procedure were less frequent in the device group (12.0% vs 20.5%; difference, -8.5%; 95% CI, -14.6% to -2.3%; P = .008). Conclusions and Relevance: In patients who are at high risk of recurrent herniation following lumbar microdiscectomy owing to a large defect in the annulus fibrosus, this study's findings suggest that annular closure with a bone-anchored implant lowers the risk of symptomatic recurrence and reoperation over 5 years of follow-up. Trial Registration: ClinicalTrials.gov Identifier: NCT01283438.

Brainatomy: A Novel Way of Teaching Sphenoid Bone Anatomy With a Simplified 3-Dimensional Model.

BACKGROUND: The diagnosis and treatment of diseases at and around the sphenoid bone demands throughout understanding of its anatomy in 3-dimensional (3-D) space. However, despite the complex anatomic nature of the sphenoid bone, the current educational resources for its 3-D anatomy are insufficient for fast and long-term retention of the anatomic relationships. OBJECTIVE: To provide a simplified 3-D model of the sphenoid bone that anyone can easily learn and recall as an internal mental model. METHODS: Various studies on the anatomy of the sphenoid bone were analyzed. The collected data included the shape, foramina, canals, fissures, and minute details of the sphenoid bone. The gained detailed knowledge was subsequently used to create a 3-D model of the sphenoid bone with the help of 3-D computer software. A live lecture was given with this same software and simultaneously recorded with a microphone and a computer-screen recorder. A novel approach in lecturing, building the sphenoid bone from the scratch in a piecemeal fashion, was utilized. RESULTS: The sphenoid bone was recreated as an horizontally elongated box without a superior and posterior wall. All its foramina, canals, and fissures are visually easy to follow. Understanding its neuroanatomic terminologies based on their anatomic nature and relationships is enhanced. CONCLUSIONS: This simplified 3-D model, along with the video lecture, will enhance the efficiency of studying sphenoid bone anatomy. The educational resources of this study can be obtained by medical students, radiologists, neurologists, neurosurgeons, neuroscientists, or anyone else seeking for fundamental understanding of sphenoid bone anatomy.

Posterolateral myelotomy for intramedullary spinal cord tumors: the other way to do it?

BACKGROUND AND PURPOSE: To evaluate posterolateral myelotomy (PLM) as a surgical method for all cases of intramedullary spinal cord tumors (IMSCT) by assessing the surgical and functional outcomes of patients treated in our clinic. MATERIALS AND METHODS: Patients with IMSCT who underwent surgery using PLM from 2013 to 2018 were reviewed retrospectively. Objective and quantitative assessment of the preoperative, postoperative, and follow-up neurological status was performed by using the modified McCormick functional schema and sensory pain scale. RESULTS: A total of 33 operations were performed on 27 patients who met the inclusion criteria. The mean grade on the McCormick functional schema increased insignificantly from 2.0 preoperatively to 2.3 immediately postoperatively and decreased back to 2.1 at the follow-up examination. Just one patient exhibited a transient proprioception deficit. Significant pain relief was observed as expressed in an improvement of mean grade on the sensory pain scale. Only in two cases was late neuropathic pain reported. A gross total resection/subtotal resection (GTR/STR) was achieved in all cases of hemangioblastoma and cavernoma, while for the majority of astrocytomas, only partial removal was accomplished. For ependymoma, which represents the most common IMSCT, a GTR/STR was realized in 12 cases (86%). A statistically significant difference (p = 0.027) was found when comparing the extent of tumor resection (EOR) between the two most common IMSCT, i.e., ependymoma and astrocytoma. CONCLUSION: PLM may be considered a reliable surgical method for IMSCT, as it combines a satisfactory EOR with reduced risk of tissue damage and excellent pain relief.

Comparison between optical coherence tomography imaging and histological sections of peripheral nerves.

OBJECTIVE: Optical coherence tomography (OCT) is an imaging technique that uses the light-backscattering properties of different tissue types to generate an image. In an earlier feasibility study the authors showed that it can be applied to visualize human peripheral nerves. As a follow-up, this paper focuses on the interpretation of the images obtained. METHODS: Ten different short peripheral nerve specimens were retained following surgery. In a first step they were examined by OCT during, or directly after, surgery. In a second step the nerve specimens were subjected to histological examination. Various steps of image processing were applied to the OCT raw data acquired. The improved OCT images were compared with the sections stained by H & E. The authors assigned the structures in the images to the various nerve components including perineurium, fascicles, and intrafascicular microstructures. RESULTS: The results show that OCT is able to resolve the myelinated axons. A weighted averaging filter helps in identifying the borders of structural features and reduces artifacts at the same time. Tissue-remodeling processes due to injury (perineural fibrosis or neuroma) led to more homogeneous light backscattering. Anterograde axonal degeneration due to sharp injury led to a loss of visible axons and to an increase of light-backscattering tissue as well. However, the depth of light penetration is too small to allow generation of a complete picture of the nerve. CONCLUSIONS: OCT is the first in vivo imaging technique that is able to resolve a nerve's structures down to the level of myelinated axons. It can yield information about focal and segmental pathologies.

The Interdisciplinary Management of Foot Drop.

BACKGROUND: Foot drop can be caused by a variety of diseases and injuries. Although it is a common condition, its overall incidence has not been reported to date. Foot drop markedly restricts the everyday activities of persons suffering from it. There is, therefore, a need for an optimized strategy for its diagnosis and treatment that would be standardized across the medical specialties encountering patients with this problem. METHODS: This article consists of a review on the basis of pertinent publications re- trieved by a search in the Pubmed/MEDLINE and Cochrane databases, as well as a description of the authors' proposed strategy for the diagnosis and treatment of foot drop. RESULTS: Foot drop can be due to a disturbance at any central or peripheral location along the motor neural pathway that terminates in the dorsiflexor muscles of the foot, or at multiple locations in series. Optimal localization of the lesion(s) is a pre- requisite for appropriate treatment and a successful outcome. The most common causes are L5 radiculopathy and peroneal nerve injury. An operation by a neuro- surgeon or spinal surgeon is a reasonable option whenever there is a realistic chance that the nerve will recover. In our opinion, any patient with a subjectively disturbing foot drop and a clinically suspected compressive neuropathy of the peroneal nerve should be informed about the option of surgical decompression of the nerve at the fibular head, which can be performed with little risk. In case of a permanent foot drop, some patients can benefit from muscle-transfer surgery. For spastic foot drop, the option of botulinum toxin injections should be evaluated. CONCLUSION: The care of patients with foot drop could be optimized by interdisciplin- ary foot-drop clinics involving all of the relevant specialists. The goals of treatment should always be improved mobility in everyday life and the prevention of falls, pain, and abnormal postures.

High-resolution in vivo imaging of peripheral nerves using optical coherence tomography: a feasibility study.

OBJECTIVE: Because of their complex topography, long courses, and small diameters, peripheral nerves are challenging structures for radiological diagnostics. However, imaging techniques in the area of peripheral nerve diseases have undergone unexpected development in recent decades. They include MRI and high-resolution sonography (HRS). Yet none of those imaging techniques reaches a resolution comparable to that of histological sections. Fascicles are the smallest discernable structure. Optical coherence tomography (OCT) is the first imaging technique that is able to depict a nerve's ultrastructure at micrometer resolution. In the current study, the authors present an in vivo assessment of human peripheral nerves using OCT. METHODS: OCT measurement was performed in 34 patients with different peripheral nerve pathologies, i.e., nerve compression syndromes. The nerves were examined during surgery after their exposure. Only the sural nerve was twice examined ex vivo. The Thorlabs OCT systems Callisto and Ganymede were used. For intraoperative use, a hand probe was covered with a sterile foil. Different postprocessing imaging techniques were applied and evaluated. In order to highlight certain structures, five texture parameters based on gray-level co-occurrence matrices were calculated according to Haralick. RESULTS: The intraoperative use of OCT is easy and intuitive. Image artifacts are mainly caused by motion and the sterile foil. If the artifacts are kept at a low level, the hyporeflecting bundles of nerve fascicles and their inner parts can be displayed. In the Haralick evaluation, the second angular moment is most suitable to depict the connective tissue. CONCLUSIONS: OCT is a new imaging technique that has shown promise in peripheral nerve surgery for particular questions. Its resolution exceeds that provided by recent radiological possibilities such as MRI and HRS. Since its field of view is relatively small, faster acquisition times would be highly desirable and have already been demonstrated by other groups. Currently, the method resembles an optical biopsy and can be a supplement to intraoperative sonography, giving high-resolution insight into a suspect area that has been located by sonography in advance.

Experimental investigations of a manually versus an electrically driven skull drill for bedside usage.

BACKGROUND: Manual skull drilling is an old but in modern neurosurgery still established procedure which can be applied quickly and universally in emergency situations. Electrical drilling requires more complex equipment and is usually reserved to the Operating Room (OR). It also seems desirable to apply an electrical drill for bedside usage but a suitable product does not exist so far. METHOD: Our experimental study using a manually and an electrically driven skull drill included a total of 40 holes drilled into synthetic biomechanical sheets. Half of the holes were produced with a prototype electrical drilling machine of the company Kaiser Technology and half of them with a traditional manual drill. Different drilling parameters such as the geometry of the borehole, the drilling forces and the drilling vibrations were captured during all experiments. RESULTS: The electrical drilling needed higher vertical force by the operators and a longer time to penetrate the sheet. A reason was the relatively lower rotational speed provided by this particular drill. When drilling electrically the vibrations were substantially less which in turn led to a more precise shape of the holes (revealed by observation via a microscope). CONCLUSIONS: The electrification of bedside drilling can in principle enable emergency craniostomies to be performed with greater ease and accuracy. The power of the electric drive, however, must be at least equivalent to the power of the traditional manual drill. Otherwise, the vertical forces exerted on the scull by the operator become inhibitive. The challenge is to combine cost-efficiency and re-sterilizability of an electrically driven drilling machine which at the same time is small and simple enough to qualify for emergency applications.

Rare finding in peripheral nerve surgery: an unicentric Castleman disease presenting as median nerve tumour.

A 51 year old man presented with progressive swelling in the upper arm. MRI revealed a solitary mass extending from the median nerve. Intraoperative finding was a tumour extending within the nerve in its proximal fibres. The histological result showed a Castleman disease.

Reliability and scientific use of a surgical planning software for anterior cervical discectomy and fusion (ACDF).

PURPOSE: Software-based planning of a spinal implant inheres in the promise of precision and superior results. The purpose of the study was to analyze the measurement reliability, prognostic value, and scientific use of a surgical planning software in patients receiving anterior cervical discectomy and fusion (ACDF). METHODS: Lateral neutral, flexion, and extension radiographs of patients receiving tailored cages as suggested by the planning software were available for analysis. Differences of vertebral wedging angles and segmental height of all cervical segments were determined at different timepoints using intraclass correlation coefficients (ICC). Cervical lordosis (C2/C7), segmental heights, global, and segmental range of motion (ROM) were determined at different timepoints. Clinical and radiological variables were correlated 12 months after surgery. RESULTS: 282 radiographs of 35 patients with a mean age of 53.1 ± 12.0 years were analyzed. Measurement of segmental height was highly accurate with an ICC near to 1, but angle measurements showed low ICC values. Likewise, the ICCs of the prognosticated values were low. Postoperatively, there was a significant decrease of segmental height (p < 0.0001) and loss of C2/C7 ROM (p = 0.036). ROM of unfused segments also significantly decreased (p = 0.016). High NDI was associated with low subsidence rates. CONCLUSIONS: The surgical planning software showed high accuracy in the measurement of height differences and lower accuracy values with angle measurements. Both the prognosticated height and angle values were arbitrary. Global ROM, ROM of the fused and intact segments, is restricted after ACDF.

Complications associated with cervical vertebral body replacement with expandable titanium cages.

Our aim was to analyze complications and risk factors for cervical vertebral body replacement (VBR) with expandable titanium cages (ETC). Fifty patients; 22 women and 28 men, mean age 61years, undergoing cervical VBR from 2010 to 2015 were analyzed. Complications were stratified by hardware-association (HA). Univariate and multivariate logistic regression was used to identify independent risk factors. Single, two and three level corpectomies were performed in 32, 15 and 3 patients respectively. A circumferential approach was necessary in 16 cases. At mean follow-up (7.3 months) 66% of patients had recovered. Radiological data showed a significant distraction (2.60mm, p<0.0001) and lordosis (5°, p=0.001). Twenty-three patients experienced 42 complications; 18 HA, 24 non-HA and 24% needed revision surgery. The number of corpectomy levels and surgical approach significantly correlated with the risk of complications (p=0.001), especially non-HA complications (p=0.002). On multivariate analysis, only the number of corpectomy levels (p<0.02, odds ratio 5.48, 95% CI 1.31-22.91) was a significant predictor of complications. We conclude that ETC are efficacious devices for cervical spine VBR, however, when used for more than 1 level, the corpectomy complication rate significantly increases.

Radiological and clinical results of patients after ACDF with and without preoperative software-assisted cage selection.

OBJECTIVE: Comparison of software facilitated preoperatively-selected cages versus standard intraoperatively-selected cages, assessing radiological and clinical outcomes of patients after single level cervical discectomy and fusion (ACDF). METHODS: Cages of study group patients were preoperatively chosen via software-aided dimensioning. Controls obtained cages determined by intraoperative trail implants. Primary endpoints were segmental height (SH), regional angulation (RA) and global cervical angulation (GCA) measured on plain radiographs before, immediately and 12 months after surgery. Neck pain on the visual analogue scale, the neck disability index, and patient satisfaction index recorded at 12 months follow up (FU) were the secondary endpoints. RESULTS: Each group comprised of 20 patients and both depicted similar demographics and operated segmental levels. Mean postoperative SH was significantly increased in both study and control groups, p<0.001* and p=0.006* respectively. Immediate postoperative gain of lordosis was only significant for the study group p<0.001*. At 12 months FU, SH and RA decreased significantly in both groups. GCA and all secondary endpoints were similar for various measured time points. The two groups did not show any significant difference for all investigated parameters. CONCLUSION: The radiographical and clinical outcomes of patients receiving cages preoperatively selected by software-assistance are similar to that of patients obtaining conventionally chosen cages. However the former allows for better regional gain/restoration of lordosis.

Lumbar juxta-facet joint cysts in association with facet joint orientation, -tropism and -arthritis: A case-control study.

OBJECTIVE: To assess the association between juxta-facet-joint cysts (JFC) occurrence at the lumbar spine and Facet Joint (FJ) orientation, -tropism and -arthritis. METHODS: Study group, 36 consecutive patients with JFC and the same number of controls, with degenerative diseases without JFC were match paired for demographics and spine segment. Parameter assessment was by T2-weighted axial MRI scans. JFC diagnosis was confirmed histopathologically. Group comparison was by Student's t-test for continuous variables and X(2) for categorical variables. RESULTS: Nineteen female and 17 male patients, aged between 45 and 85 years (mean 67.19 ± 10.3 years) had a mean JFC size of 9.26 ± 4.8mm occurring most frequently in the segment L4-L5 (75% n=25) and on the left side (61%). Mean FJ orientation of the study group was significantly more coronal compared to controls (left side 42° vs 36°, p<0.02*, 95% confidence interval: 0.9-11.5 and right side 43° vs 37°, p<0.02*, 95% confidence interval: 0.6-10.6 respectively). However, individual intersegmental analysis for study group patients showed the JFC bearing side to be significantly more sagittally oriented 40° ± 11.2° compared to 45° ± 13.2° for the side without FJC (p<0.03*, 95% confidence interval: 8.1-1.7). 50% of the study group showed FJ asymmetry compared to 30% in controls, with a trend for FJ tropism (p<0.07). Severe (grade 3) FJ arthritis was significantly more predominant in the study group 23/33 (p<0.001*) as compared to controls. CONCLUSIONS: Compared to a control group, JFC occurrence is associated with significant higher rates of arthritis and coronally orientated FJ. At intersegment comparison within the same patient cysts located in more sagittally orientated FJ and the asymmetric segments show a trend for FJ tropism.

Repeat-surgery at Glioblastoma recurrence, when and why to operate?

OBJECTIVE: Glioblastoma (GB) recurrence is inevitable; guidelines for treatment at disease recurrence are deficient. Clinicians are faced with deciding whom to choose for repeat-surgery. This study analyzes recurrence therapy modalities, investigates characteristics of patients operated on at recurrence and evaluates outcome benefit. METHODS: Consecutive adult patients operated on for de novo GB at a single institution from 2006 to 2011 were reviewed. Clinical, radiographic and molecular data of 141 patients diagnosed of recurrent disease were assessed. Reasons for recurrence therapy and therapy modalities were reviewed. Univariate analysis was used to analyze differences in parameters of patients operated on at recurrence and those not. Impact of re-operation on survival was evaluated by the Kaplan-Meier method and Log-rank test. RESULTS: 53 (38%) patients were selected for repeat surgery upon recurrent disease, this was followed by either chemotherapy (CT) (40%), radiotherapy (8%) or both (49%). 57 (40%) patients received CT alone, which was the most frequent mono-second-line therapy opted for. Most frequent indications for repeat-surgery were maximum possible tumor resection mass reduction and symptom relief (62% and 21%, respectively). Univariate analysis of re-operated vs. not operated patients, showed significant differences for age (p=0.0001*) and Karnofsky Performance status (KPS) >70 at both primary and repeat tumor resection (p=0.013* and 0.0001*, respectively). The operated group had a significantly lower Charlson-comorbidity-index≤3 (p=0.004*) and larger tumor size (p=0.0001*). Complication risk at recurrence was not significantly different between groups (p=0.069). However, patients chosen for repeat surgery had significantly less complications at index surgery (p=0.006*). Median time from recurrence to death was 11 months (range, 1-33 months) for operated patients as opposed to 5 months (range, 0-22 months) for not operated patients. The former survived significantly longer; 19 months compared to 13 months for those not operated upon (p=0.002*). CONCLUSIONS: Our study depicts that patients eligible for repeat-surgery at GB recurrence are characterized by a KPS>70% before primary and repeat-surgery, Charlson-comorbidity-index≤3, large tumor size and young age. These well-selected patients survive significantly longer after repeat-surgery without being at a higher complication risk in comparison to patients not operated upon.

Risk factors for glioblastoma therapy associated complications.

OBJECTIVE: Thromboembolic events, seizures, neurologic symptoms and adverse effects from corticosteroids and chemotherapies are frequent clinical complications seen in Glioblastoma (GB) patients. The exact impact these have on dismal patient outcome has not been fully elucidated. We aimed at assessing treatment associated complications, evaluating the impact on survival and defining risk factors. METHODS: Two hundred and thirty three consecutive adult patients operated on for newly diagnosed GB at a single tertiary institution over a 5-year-period (2006-2011) were assessed. Demographic parameters (age, gender, comorbidity status quantified by the Charlson-comorbidity-index (CCI), functional status computed by the Karnofsky Performance Scale (KPS), tumor characteristics (size, location, IDH-1 mutation and MGMT-Promotor-methylation-status) and treatment parameters (volumetrically quantified extent of resection and adjuvant therapy) were retrospectively reviewed. Complications assessed were recorded as neurological (N), surgical (S) and medical (M). Independent risk factor analysis was performed by the univariate and multivariate logistic regression method. Survival analysis was plotted by the Kaplan-Meier-method, influence of complication occurrence was evaluated by the log-rank test. RESULTS: One hundred and fifty nine (68.2%) patients had a total of 281 complications (90 N, 174 M and 17 S). Univariate analysis identified age (P=0.003), KPS<70 (P=0.002), CCI>3 (P=0.03), eloquent tumor location (P=0.001) and therapy other than the standard radio-chemotherapy with temozolomide therapy (P=0.034) as risk factors for complications. Multivariate analysis extracted the eloquent tumor location (P=0.007, odds ratio 1.94) as a significant predictor for complications. Having a complication significantly decreased patient survival (P=0.015). CONCLUSIONS: Complications significantly decrease GB patient survival. Age, poor functional status, other than standard adjuvant therapy and eloquent tumor location proved as significant risk factors for encountering a therapy associated complication. Not extensive surgery or tumor size but surgery at eloquent locations impacts complication occurrence the strongest with a 2 fold increased complication occurrence risk.

Core herniation after implantation of a cervical artificial disc: case report.

INTRODUCTION: Cervical artificial discs (CADs) represent an established surgical option in selected patients with cervical spinal disc degeneration. Though CADs have been available for many years, there is a lack of information concerning long-term safety, durability and implant-related failure rates. MATERIALS AND METHODS: The authors describe the failure of a M6-C CAD (Spinal Kinetics, Sunnyvale, CA, USA). RESULTS: Eight years after implantation of a CAD of the M6 type, a 39-year-old female presented with new clinical signs of cervical myelopathy. Radiologically, medullar compression due to posterior core herniation was the suspected cause. The damaged CAD was removed and the segment fused. During revision surgery, rupture of the posterior structures could be detected. Possible mechanisms leading to implant failure are discussed. CONCLUSION: As there is no standard regarding clinical and radiological follow-up for patients with CADs, radiological long-term follow-up investigations seem to be justified for exclusion of implant failure.

Influence of cervical bone mineral density on cage subsidence in patients following stand-alone anterior cervical discectomy and fusion.

PURPOSE: Anterior cervical discectomy and fusion (ACDF) is a common procedure for the treatment of cervical degenerative diseases. However, cage subsidence remains a frequent problem. We therefore investigated if cage design and site-specific bone mineral density (BMD) contribute to the rate and direction of subsidence following ACDF. METHODS: Patients were prospectively included and received two different cages (groups 1 and 2) using minimization randomization. The degree and direction of cage subsidence were determined using plain radiographs. Neck pain intensity on the visual analogue scale (VAS), the neck disability index (NDI), and the patient satisfaction index were recorded up to 12 months after surgery. RESULTS: 88 patients were analysed with a mean age of 53.7 ± 11.8 years. BMD values decreased in craniocaudal direction from 302.0 ± 62.2 to 235.5 ± 38.9 mg/cm(3). Both groups showed significant height gain after the operation (both p < 0.001), followed by height loss at 3 months (both p < 0.05) and at 3-12 months after the operation (both p > 0.05). Both groups showed improvement of VAS neck pain intensity (both p < 0.05) and NDI (both p < 0.05). The direction of cage subsidence was similar, no correlations were found between cage subsidence and BMD or various clinical parameters. CONCLUSIONS: Implant geometry of both cages and variations of the operative procedure promoted a relatively high degree of cage subsidence. Further studies are necessary to identify a relation of BMD and subsidence using optimized implant geometry and by controlling additional intraoperative variables.

Sonographic examination of the median nerve in dialysis patients and after renal transplantation.

OBJECTIVE: Patients with renal insufficiency are predisposed to develop CTS (carpal tunnel syndrome). In particular, long-term dialysis seems to contribute to changes in median nerve texture which lead to an increased risk for CTS. The current study was designed to evaluate if these structural changes can be detected by HRS (high-resolution sonography). Additionally, the current study aimed to determine if changes are reversible after termination of dialysis. METHODS: Fifty patients (98 hands) were included in the study. The study population was subdivided into three groups: patients without any history of renal disease (H, n = 20), patients with long-term dialysis (D, n = 10), and patients after renal transplantation (TX, n = 20). None of the patients had any clinical symptoms for a median nerve compression syndrome. The CSA (cross-sectional area) of the median nerve was evaluated both 12 cm proximally of the carpal tunnel inlet and directly at the carpal tunnel inlet. The ratio of those two values, the WFR (wrist forearm ratio), was calculated and analyzed. RESULTS: The CSA demonstrated significantly higher values in dialysis (D) and transplanted (TX) patients compared to the healthy (H) control group (P < 0.001). No significant differences were detectable between the D and TX groups. Specifically, there was no significant difference in the WFR. CONCLUSION: Patients with chronic renal disease demonstrate significantly higher CSA values compared to their healthy counterparts. Termination of dialysis does not seem to reverse these morphological changes.

Spinal metastasis of gliosarcoma: array-based comparative genomic hybridization for confirmation of metastatic spread.

We report a 64-year-old woman who underwent craniotomy and gross total resection of a left frontal lobe tumor initially diagnosed as glioblastoma. Multiple wound revisions were necessary due to repeated wound healing disorders under concomitant radio-chemotherapy. After 9 months there was local cranial tumor recurrence, requiring re-operation. Thereafter, temozolomide monotherapy was implemented. Histologically, a shift from glial to mesenchymal differentiation was observed in the recurrent tumor, resulting in the diagnosis of gliosarcoma. A further 9 months later a thoracic spinal tumor occurred requiring emergency tumor resection. Analysis showed a mesenchymal tumor without definite glial component. Being resistant to local radiation therapy, symptomatic local spinal tumor progression was observed within 1 month requiring re-resection. There was no response to chemotherapy with bevacizumab and irinotecan. Considering the pronounced sarcoma-like differentiation, a sarcoma chemotherapy regime with doxorubicin was initiated. This was also to no avail; the disease progressed and recurred at both the spinal and cerebral locations, respectively. This ambiguous tumor characteristic and therapy resistance encouraged us to retrospectively perform molecular and array-based comparative genomic hybridization (aCGH) analysis on the extirpated cerebral and spinal tumors. Tumors from both locations showed a consistent cytogenetic signature of gain of chromosome 7, and losses of chromosomes 10 and 13. This novel report of aCGH analysis of spinal gliosarcoma metastasis and the correlation to the clinical disease course shows that genotypic profiling may serve as a supplementary diagnostic tool in improving our knowledge of the biologic behavior of rare tumor variants.

Clinical relevance of neuroforaminal patency after anterior cervical discectomy and fusion.

BACKGROUND: We sought to investigate the clinical relevance of neuroforaminal patency and facet degeneration one year after anterior cervical discectomy and fusion (ACDF). Previous studies were characterized by imprecise techniques and fragmentary measurements, and most lacked reliable clinical data and correlation analyses. METHODS: Patients with cervical mono- or bi-level degenerative pathology were prospectively included. Neuroforaminal size and segmental height were determined quantitatively, and the degree of facet degeneration was assessed qualitatively before and one year after the operation, by computed tomography. Clinical data, such as the severity of neck and arm pain, were assessed on a visual analogue scale (VAS) from 0 to 10, and neck disability index (NDI) was recorded before and one year after the operation. Their correlation with radiological data was investigated. RESULTS: Seventy-nine patients aged 53.3 ± 11.3 years were included. One year after surgery, median VAS pain intensity was still significantly improved (neck, from 5 to 1; right arm, from 2 to 1; left arm, from 4 to 1) as was NDI (from 40 to 20). Neuroforaminal size showed a reduction on both sides (left, 0.0289 ± 0.09 cm(2); right, 0.0149 ± 0.08 cm(2)). One year after the operation, segmental height decreased and facet degeneration increased from measures taken before the operation. No correlations were found between neuroforaminal stenosis or the degree of facet degeneration and various clinical outcome parameters. CONCLUSIONS: The decrease in segmental height one year after ACDF leads in turn to secondary neuroforaminal stenosis and progressive facet degeneration. Of the various neuroforaminal variables used, none revealed a threshold value indicative of the presence or severity of radicular arm pain. This absence of correlation between imaging and clinical information is important and should be considered when allocating patients for surgical interventions.