Francesco Tomasello

Does early decompression improve neurological outcome of spinal cord injured patients? Appraisal of the literature using a meta-analytical approach

Study design: Definitive and unequivocal evidence to support the practice of early or late surgery is still lacking in clinical studies. Accordingly, meta-analysis is one of the few methods that offer a rational, statistical approach to management decision. A review of the clinical literature on spinal cord injury with emphasis on the role of early surgical decompression and a meta-analysis of results was performed.Objectives: To determine whether neurological outcome is improved in traumatic spinal cord-injured patients who had surgery within 24 h as compared with those who had late surgery or conservative treatment.Methods: A Medline search covering the period 1966–2000, supplemented with manual search, was used to locate studies containing information on indication, rationale and timing of surgical decompression after spinal cord injuries. The analysis included a total of 1687 eligible patients.Results: Statistically, early decompression resulted in better outcome compared with both conservative (P<0.001) and late management (P<0.001). Nevertheless, analysis of homogeneity showed that only data regarding patients with incomplete neurological deficits who had early surgery were reliable.Conclusions: Although statistically the percentage of patients with incomplete neurological deficits improving after early decompression appear 89.7% (95% confidence interval: 83.9, 95.5%), to be better than with the other modes of treatment when taking into consideration the material available for analysis and the various other factors including clinical limitations; early surgical decompression can only be considered as practice option for all groups of patients.

Anterior skull base reconstruction with a galeal-pericranial flap.

Excision of neoplasm and trauma involving the anterior cranial base may often result in communication between the intracranial and extracranial compartments. Many techniques have been proposed to obtain a watertight separation. We report our 5 years of experience in the management of anterior skull base defects using a galeal-pericranial flap. Between January 2001 and April 2006, 22 patients were treated for a cranial base reconstruction at the University of Messina. Five of them presented with persistent cerebrospinal fluid (CSF) leak after previous craniofacial trauma. Ten underwent a combined maxillofacial-neurosurgical approach for the removal of a benign tumor involving the anterior skull base. Seven had severe craniofacial trauma, which required an intervention of reconstruction of the anterior skull base. In the whole series, a galeal-pericranial flap was used to separate intra- and extracranial compartments. No patients developed postoperative brain contusions or subdural-epidural blood collections. Throughout the follow-up period, there was no evidence of flap failure. In all but one patient, no postoperative CSF leak was evident. In one patient, a mild transient postoperative CSF leakage was present. There has been no recurrent CSF leak or meningitis. The follow up average of 23 months shows no incidence of infection. Even if our series does not comprise malignancies and previously irradiated patients, our data confirm the validity of the galeal- pericranial flap for the surgical management of minimal and moderately sized defects of anterior cranial base.

Fibrin Sealants in Dura Sealing: A Systematic Literature Review

Background Fibrin sealants are widely used in neurosurgery to seal the suture line, provide watertight closure, and prevent cerebrospinal fluid leaks. The aim of this systematic review is to summarize the current efficacy and safety literature of fibrin sealants in dura sealing and the prevention/treatment of cerebrospinal fluid leaks. Methods A comprehensive electronic literature search was run in the following databases: Cochrane Database of Systematic Reviews, Cochrane Central Resister of Controlled Trials, clinicaltrials.gov, MEDLINE/PubMed, and EMBASE. Titles and abstracts of potential articles of interest were reviewed independently by 3 of the authors. Results A total of 1006 database records and additional records were identified. After screening for duplicates and relevance, a total of 78 articles were assessed by the investigators for eligibility. Thirty-eight were excluded and the full-text of 40 articles were included in the qualitative synthesis. Seven of these included only safety data and were included in the safety assessment. The remaining 33 articles included findings from 32 studies that enrolled a total of 2935 patients who were exposed to fibrin sealant. Among these 33 studies there were only 3 randomized controlled trials, with the remaining being prospective cohort analysis, case controlled studies, prospective or retrospective case series. One randomized controlled trial, with 89 patients exposed to fibrin sealant, found a greater rate of intraoperative watertight dura closure in the fibrin sealant group than the control group (92.1% versus 38.0%, p<0.001); however, post-operative cerebrospinal fluid leakage occurred in more fibrin sealant than control patients (6.7% versus 2.0%, p>0.05). Other clinical trials evaluated the effect of fibrin sealant in the postoperative prevention of cerebrospinal fluid leaks. These were generally lower level evidence studies (ie, not prospective, randomized, controlled trials) that were not designed or powered to demonstrate a significant advantage to fibrin sealant use. Two small case series studies evaluated the effect of fibrin sealants in persistent cerebrospinal fluid leak treatment, but did not establish firm efficacy conclusions. Specific adverse reports where fibrin sealants were used for dura sealing were limited, with only 8 cases reported in neurosurgical procedures since 1987 and most reporting only a speculative relationship/association with fibrin sealant exposure. Conclusions A major finding of this systematic literature review is that there is a paucity of randomized studies that have evaluated the effectiveness and safety of fibrin sealants in providing intraoperative watertight dura closure and post-operative cerebrospinal fluid leakage. Among the limited studies available, evidence from a single randomized, controlled trial indicates that fibrin sealants provide a higher rate of intraoperative watertight closure of the dura suture line than control, albeit with a higher rate of postoperative cerebrospinal fluid leakage. Evidence from non-randomized, controlled trials suggests that fibrin sealants may be effective in preventing cerebrospinal fluid leaks with an acceptable safety profile. There is a substantial need for randomized, controlled clinical trials or well-designed prospective observational trials where the conduct of a randomized trial is not feasible to fully assess the impact of fibrin sealant utilization on the rates of intraoperative dura closure, postoperative cerebrospinal leakage, and safety.

Microvascular Decompression for Trigeminal Neuralgia: Technical Refinement for Complication Avoidance

BACKGROUND Microvascular decompression (MVD) represents the most effective and safe surgical option for the treatment of trigeminal neuralgia since it was first popularized by Jannetta 50 years ago. Despite several advances, complications such as cerebellar and vascular injury, hearing loss, muscular atrophy, cerebrospinal fluid (CSF) leak, postoperative cutaneous pain, and sensory disturbances still occur and may negatively affect the outcome. We propose some technical nuances of the surgical procedure that were used in our recent series. METHODS We used a novel hockey stick-shaped retromastoid skin incision, preserving the major nerves of the occipital and temporal areas. Microsurgical steps were performed without the use of retractors. CSF leakage was prevented with a watertight dural closure and multilayer osteodural reconstruction. RESULTS The refined surgical steps were perfected in the last consecutive 15 cases of our series. In these cases we did not record any cutaneous pain, sensory disturbances, or CSF leakage. The average diameter of the craniectomy was 18 mm. No patient reported major complications related to the intradural microsurgical maneuvers. In all cases the neurovascular conflict was found and solved with a good outcome in terms of pain disappearance. CONCLUSIONS Our minimally invasive approach was demonstrated to guarantee an optimal exposure of the cerebellopontine angle and minimize the rate of complications related to skin incision and muscular dissection, microsurgical steps, and closure.

Gliomas Biology: Angiogenesis and Invasion

Glial tumors, within neuroepitelial-derived lesions, are the most common intra-assial neo‐ plastic histotypes. Gliomas account for about 45% of all primary central nervous system (CNS) tumors and 77% of all malignant primary CNS tumors. Gliomas can originate from neural stem cells, progenitor cells, or from de-differentiated mature neural cells transformed into cancer stem cells. Although brain tumors constitute only a small proportion of overall human malignancies, they carry high rates of morbidity and mortality. Mortality is still close to 100% and the average survival of patients with glioblastoma multiforme (GBM) is less than 1 year when classical treatment is used. Recent progresses in multimodal treatment has led to only a slight increase in average survival up to 15-18 months [1]. The effectiveness of the actual chemotherapeutic approach and multimodal targeted therapies remains modest in gliomas.

Intraoperative Neurophysiological Monitoring in Spine Surgery: A Significant Tool for Neuronal Protection and Functional Restoration.

Although there is recent evidence for the role of intraoperative neurophysiological monitoring (IONM) in spine surgery, there are no uniform opinions on the optimal combination of the different tools. At our institution, multimodal IONM (mIONM) approach in spine surgery involves the evaluation of somatosensory evoked potentials (SEPs) and motor evoked potentials (MEPs) with electrical transcranial stimulation, including the use of a multipulse technique with multiple myomeric registration of responses from limbs, and a single-pulse technique with D-wave registration through epi- and intradural recording, and free running and evoked electromyography (frEMG and eEMG) with bilateral recording from segmental target muscles. We analyzed the impact of the mIONM on the preservation of neuronal structures and on functional restoration in a prospective series of patients who underwent spine surgery. We observed an improvement of neurological status in 50 % of the patients. The D-wave registration was the most useful intraoperative tool, especially when MEP and SEP responses were absent or poorly recordable. Our preliminary data confirm that mIONM plays a fundamental role in the identification and functional preservation of the spinal cord and nerve roots. It is highly sensitive and specific for detecting and avoiding neurological injury during spine surgery and represents a helpful tool for achieving optimal postoperative functional outcome.

Navigated Brain Stimulation (NBS) for Pre-Surgical Planning of Brain Lesion in Critical Areas: Basic Principles and Early Experience

Direct cortical stimulation (DCS) is an intraoperative technique that uses electrodes placed directly on the exposed cortical surface of the brain to stimulate activity of functional areas by simultaneously recording the evoked responses peripherally. DCS is very precise and re‐ liable and can be considered the gold standard in brain mapping and intraoperative func‐ tional monitoring. Nevertheless, the neurosurgeon discovers the spatial relationship between the disease and eloquent cortical surfaces only after having completed a cranioto‐ my and dural opening.