Sleep apnoea adversely affects the outcome in patients who undergo posterior lumbar fusion: a population-based study.

Despite the increasing prevalence of sleep apnoea, little information is available regarding its impact on the peri-operative outcome of patients undergoing posterior lumbar fusion. Using a national database, patients who underwent lumbar fusion between 2006 and 2010 were identified, sub-grouped by diagnosis of sleep apnoea and compared. The impact of sleep apnoea on various outcome measures was assessed by regression analysis. The records of 84,655 patients undergoing posterior lumbar fusion were identified and 7.28% (n = 6163) also had a diagnostic code for sleep apnoea. Compared with patients without sleep apnoea, these patients were older, more frequently female, had a higher comorbidity burden and higher rates of peri-operative complications, post-operative mechanical ventilation, blood product transfusion and intensive care. Patients with sleep apnoea also had longer and more costly periods of hospitalisation. In the regression analysis, sleep apnoea emerged as an independent risk factor for the development of peri-operative complications (odds ratio (OR) 1.50, confidence interval (CI) 1.38;1.62), blood product transfusions (OR 1.12, CI 1.03;1.23), mechanical ventilation (OR 6.97, CI 5.90;8.23), critical care services (OR 1.86, CI 1.71;2.03), prolonged hospitalisation and increased cost (OR 1.28, CI 1.19;1.37; OR 1.10, CI 1.03;1.18). Patients with sleep apnoea who undergo posterior lumbar fusion pose significant challenges to clinicians.

Vertebroplasty combined with image-guided percutaneous cement augmented transpedicular fixation for the treatment of complex vertebral fractures in osteoporotic patients.

AIM: Surgical management of osteoporotic fractures constitutes a clinical challenge. The aim of this study was to evaluate feasibility and efficacy of navigated percutaneous screw fixation combined with multisegmental vertebroplasty for the treatment of osteoporotic fractures not suitable for monosegmental cement augmentation in patients with severe osteoporotic changes of the vertebral column and/or progressive kyphotic deformation. METHODS: Navigated percutaneous screw fixation and simultaneous augmentation with vertebroplasty was performed in 6 patients with lumbar and 4 patients with thoracic osteoporotic fractures. In all cases, significant vertebral body collapse, destruction of the endplates and multisegmental osteoporotic changes were radiologically confirmed. Postoperative images were obtained in all cases to analyze the position of each screw and to assess further deformity progression. Follow-up ranged between 12 and 18 months. RESULTS: There was no additional morbidity associated with screw or cement insertion. Cement leakage lateral to the vertebral body was observed in 4 cases. Mean total operation time (142 minutes) was prolonged due to intraoperative data acquisition for 15±6 minutes. In 2 cases a second data set had to be acquired due to poor image quality. Finally, mean intraoperative blood loss was 100ml. Clinical outcome was satisfactory in all cases. Radiological follow-up demonstrated loss of initial kyphosis correction in 8 cases. CONCLUSION: Navigated percutaneous screw fixation combined with multisegmental vertebroplasty is a technically feasible procedure. Despite the additional time needed for intraoperative data acquisition, total operation time was acceptable and intraoperative blood loss as well as muscle trauma were minimized compared to a standard open procedure. Despite good clinical outcome, the described construct failed to prevent further kyphotic deformation during the reported follow-up period.

Minimally invasive removal of an extradural intraradicular lumbar schwannoma.

OBJECTIVE: Surgical exposure of peripheral lumbar schwannomas often requires extensive muscle mobilization which results in significant postoperative pain. We describe an alternative minimally invasive surgical technique for the treatment of such lesions. METHODS: We report the case of a patient with an extradural intraradicular schwannoma of the L4 root that was treated with a minimally invasive transmuscular approach by using tubular retractors. RESULTS: Muscle trauma and intraoperative blood loss were negligible. The postoperative course was uneventfull. There was no additional morbidity associated with the approach. The patient was discharged 72 h after the procedure. CONCLUSIONS: In selected cases extradural intraradicular lumbar schwannomas can be treated adequately with a minimally invasive transmuscular approach.

Minimally invasive approach for the treatment of lateral lumbar disc herniations. Technique and results.

OBJECTIVE: This paper aims to demonstrate the feasibility and efficacy of a minimal invasive approach by using a muscle dilator system for the treatment of lateral lumbar disc herniations. METHODS: A retrospective analysis of 38 cases with lateral lumbar disc herniations that were treated the METRx-System was performed. Patients were assessed preoperatively and postoperatively with the visual analogue scale (VAS) for leg pain. Follow up ranged from 6 to 24 months. RESULTS: No intraoperative complications were observed. Operation time and intraoperative blood loss were minimized. In 37 cases VAS scores were significantly lower after the procedure. A single patient had to be reoperated due to insufficient removal of the herniated disc material. CONCLUSION: The reported minimal invasive technique is a safe and efficient alternative to conventional methods for the treatment of lateral lumbar disc herniations.

Benefits and limitations of image guidance in the surgical treatment of intracranial dural arteriovenous fistulas.

BACKGROUND: Despite major advances in endovascular embolization techniques, microsurgical resection remains a reliable and effective treatment modality for dural arteriovenous fistulas (DAVF). However, intraoperative detection of these lesions and identification of feeding arteries and draining veins can be challenging. In a series of 6 patients who were not candidates for definitive treatment by endovascular embolization we evaluated the benefits and limitations of computer-assisted image guidance for surgical ablation of DAVF. METHODS: Of the 6 patients, 5 presented with haemorrhage and one with seizures. Diagnosis of DAVF was made by conventional angiography and dynamic contrast enhanced MR angiography (CE-MRA). All patients were surgically treated with the assistance of a 3D high resolution T1-weighted MR data set and time-of-flight MR angiography (MRA) obtained for neuronavigation. Registration was based on cranial fiducials and image-guided surgery was performed with the navigation system. FINDINGS: Four of the 6 patients suffered from DAVF draining into the superior sagittal sinus, one fistula drained into paracavernous veins adjacent to the superior petrosal sinus and one patient had a pial fistula draining in the straight sinus. DAVF diagnosed with conventional angiography could be located on CE-MRA and MRA prior to surgery. MRI and MRA images were combined on the neuronavigation workstation and DAVF were located intraoperatively by using a tracking device. In 4 out of 6 cases neuronavigation was used for direct intraoperative identification of DAVF. Brain shift prevented direct tracking of pathological vessels in the other 2 cases, where navigation could only be used to assist craniotomy. Microsurgical dissection and coagulation of the fistulas led to complete cure in all patients as confirmed by angiography. CONCLUSIONS: Neuronavigation may be used as an additional tool for microsurgical treatment of DAVF. However, in this small series of 6 cases, surgical procedures have not been substantially altered by the use of the neuronavigation system. Image guidance has been beneficial for the location of small, superficially located DAVF, whereas a navigated approach to deep-seated lesions was less accurate due to the familiar problem of brain shift and brain retraction during surgery.

Neurosurgical interventions during pregnancy and the puerperium: clinical considerations and management.

Neurosurgical interventions during pregnancy represent a special clinical challenge and require a meticulously selected treatment strategy. A thorough understanding of the underlying pathophysiological mechanisms involving mother and fetus is mandatory. We report our experience with neurosurgical procedures during pregnancy and the puerperium and summarize the difficulties encountered. The emerging diagnostic as well as therapeutic implications in these complex cases are also discussed.

Neurosurgical interventions in children with Maroteaux-Lamy syndrome. Case report and review of the literature.

This paper reports the case of a 14-year-old child with Maroteaux-Lamy syndrome (mucopolysaccharidosis type 6) who was treated consecutively for compressive damage of the optic nerves, hydrocephalus communicans and progressive spastic tetraparesis within 2 years. The clinical course of the patient is presented and the pathophysiologic mechanisms of disease progression in patients with Maroteaux-Lamy syndrome are discussed and reviewed.

Effects of the immunomodulator linomide on macrophage migration and myelin phagocytic activity in peripheral nerve trauma: an experimental study.

Wallerian degeneration after peripheral nerve transection leads to the phagocytosis of degenerated myelin and axon components by macrophages. These phagocytes are recruited from the systemic circulation and Wallerian degeneration may therefore be used as a model for myelin removal by hematogenous macrophages, a feature that is also a hallmark of demyelinating diseases of the central and peripheral nervous system. The immunomodulator linomide has been shown to be effective in the treatment of experimental demyelinating diseases although the exact mode of its action is not yet defined. The present study investigated the effect of linomide on monocyte invasion and myelin phagocytosis after sciatic nerve transection. Linomide had a dual effect in Wallerian degeneration. Monocyte migration from the circulation to the damaged nervous system was significantly reduced. Additionally, the myelin phagocytic capacity of macrophages was impaired, finally resulting in a significant delay in the removal of myelin. The present experiments may provide an explanation for the effects of linomide during the course of demyelinating diseases of the nervous system.

Involvement of intercellular adhesion molecule-1 in myelin recognition by macrophages.

Macrophages play a crucial role in myelin removal during nerve degeneration and demyelination. The exact mechanisms of myelin recognition and uptake are not yet defined. The present experiments aimed at defining the role of intercellular adhesion molecule-1 (ICAM-1) in this process. Myelin phagocytosis was studied in an established in vitro model of cultured macrophages and sciatic nerves. Cocultures of wild-type C57BL macrophages with sciatic nerves resulted in a massive invasion of the nerves by macrophages with subsequent removal of myelin. In contrast, when macrophages of ICAM-1-deficient animals were cocultured with wild-type nerves, myelin phagocytosis was significantly retarded, whereas cell invasion was completely undisturbed. These data indicate that the ICAM-1 molecule acts as a costimulatory signal in myelin recognition and uptake by macrophages.

Inflammatory CNS demyelination: histopathologic correlation with in vivo quantitative proton MR spectroscopy.

BACKGROUND AND PURPOSE: The mechanisms behind the demyelination that is characteristic of multiple sclerosis (MS) are still poorly understood. The purpose of this study was to compare immunopathologic findings in demyelinating lesions of three patients with in vivo assessments obtained by quantitative proton MR spectroscopy (MRS). METHODS: Between four and seven stereotactic needle brain biopsies were performed in three young adults with diagnostically equivocal findings for MS. Axonal density, gliosis, blood brain-barrier breakdown, and demyelinating activity of lesions were determined. Combined MR/MRS studies were performed (T1-weighted fast low-angle shot and single-voxel stimulated-echo acquisition mode), and absolute metabolite levels were obtained with a user-independent fitting routine. Metabolite control values were obtained from a group of age-matched healthy volunteers (n = 40, age range, 20-25 years old). Alterations of metabolite levels of control subjects were considered significant when exceeding two standard deviations. RESULTS: There were parallel decreases of N-acetylaspartate (21%-82%) and reductions of axonal density (44%-74%) in demyelinating plaques. Concomitant increases of choline (75%-152%) and myo-inositol (84%-160%) corresponded to glial proliferation. Elevated lactate was associated with inflammation. CONCLUSION: The present data suggest that in vivo MRS indicates key pathologic features of demyelinating lesions.

Radioimmunotherapy of colorectal cancer in small volume disease and in an adjuvant setting: preclinical evaluation in comparison to equitoxic chemotherapy and initial results of an ongoing phase-I/II clinical trial.

The 5-year survival of colorectal cancer patients with distant metastases is below 30%, despite the development and use of a variety of chemotherapeutic regimens. Therefore, new therapeutic strategies are warranted. Whereas radioimmunotherapy (RIT) has shown disappointing results in bulky disease, it may be a promising therapeutic alternative in limited and small volume disease. The aim of this study was, therefore, to compare, in a preclinical study, the therapeutic efficacy of RIT in colorectal cancer to equitoxic chemotherapy, as well as to evaluate, in a pilot clinical trial, its efficacy in small volume disease. Nude mice, bearing subcutaneous or metastatic human colon cancer xenografts, were injected either with the unlabeled or 131I-labeled monoclonal antibodies (MAbs), CO17-1A (which is a murine IgG2a directed against a 41-kD membrane glycoprotein) or F023C5 (which is an anti-CEA MAb of murine IgG1 subtype), or were administered 5-fluorouracil/folinic acid (5-FU/LV) at equitoxic doses. In a pilot clinical study, 10 colorectal cancer patients with small volume metastatic disease (all lesions < or = 3 cm) have been entered so far in an ongoing mCi/m2-based dose escalation study with the 131I-labeled F023C5. In the animals, the maximum tolerated activities (MTD) of 131I-labeled CO17-1A and F023C5 were 300 microCi and 600 microCi, respectively, corresponding to blood doses of approximately 15 Gy each. Accordingly, myelotoxicity was dose-limiting. The MTD in the chemotherapy group was 0.6 mg 5-FU/1.8 mg LV, given as intravenous bolus 1 h apart for 5 subsequent days. Whereas no significant therapeutic effects were seen with both unlabeled MAbs or 5-FU/LV chemotherapy, tumor growth was retarded significantly with both radiolabeled antibodies. In the metastatic model, chemotherapy prolonged life for only a few weeks, whereas RIT led to cures in 35-55% of the animals. As was the case in the animals, myelotoxicity seems to be dose-limiting in patients as well. Encouraging anti-tumor effects were observed, lasting for up to more than 12 months. These data suggest that radioimmunotherapy may be a viable therapeutic option in colorectal cancer patients with limited disease. Myelotoxicity is the only dose-limiting organ toxicity. Although most patients were treated below the MTD, anti-tumor effects are encouraging. Further studies are ongoing.

Wallerian degeneration in ICAM-1-deficient mice.

Wallerian degeneration of the peripheral nervous system was studied in ICAM-1-deficient mice and compared with the phenomena observed in C57BL wild-type animals. There was a decrease in myelin density in both mice strains 4 and 6 days after transection of the sciatic nerve. The degenerating nerves were invaded by Mac-1-, LFA-1-, and F4/80-positive macrophages; significantly lower numbers of macrophages were present in ICAM-1-deficient nerves. Myelin loss decreased after nerve transection with a more prominent loss in ICAM-1-deficient animals. Schwann cells revealed a much higher myelin load in these animals when compared with wild-type nerves, and there was an increased proliferation of endoneurial cells in ICAM-1-deficient mice. These data indicate that ICAM-1 is involved in macrophage recruitment to injured peripheral nerves as well as in the proliferative and phagocytic response of Schwann cells after peripheral nerve transection.