Rima S. Rindler

Complications following cranioplasty and relationship to timing: A systematic review and meta-analysis

The optimal timing of cranioplasty after decompressive craniectomy has not been well established. The purpose of this study was to evaluate the relationship between timing of cranioplasty and related complications. A systematic search of MEDLINE, Scopus, and the Cochrane databases was performed using PRISMA guidelines for English-language articles published between 1990 and 2015. Case series, case-control and cohort studies, and clinical trials reporting timing and complication data for cranioplasty after decompressive craniectomy in adults were included. Extracted data included overall complications, infections, reoperations, intracranial hemorrhage, extra-axial fluid collections, hydrocephalus, seizures, and bone resorption for cranioplasty performed within (early) and beyond (late) 90days. Twenty-five of 321 articles met inclusion criteria for a total of 3126 patients (1421 early vs. 1705 late). All were retrospective observational studies. Early cranioplasty had significantly higher odds of hydrocephalus than late cranioplasty (Odds Ratio [OR] 2.38, 95% Confidence Interval [CI] 1.25-4.52, p=0.008). There was no difference in odds of overall complications, infections, reoperations, intracranial hemorrhage, extra-axial fluid collections, seizures, or bone resorption. Subgroup analysis of trauma patients revealed a decreased odds of extra-axial fluid collection (OR 0.30, p=0.02) and an increased odds of hydrocephalus (OR 4.99, p=0.05). Early cranioplasty within 90days after decompressive craniectomy is associated with an increased odds of hydrocephalus than with later cranioplasty, but no difference in odds of developing other complications. Earlier cranioplasty in the trauma population is associated with fewer extra-axial fluid collections.

Early Cranioplasty is Associated with Greater Neurological Improvement: A Systematic Review and Meta-Analysis

BACKGROUND Cranioplasty after decompressive craniectomy is a common neurosurgical procedure, yet the optimal timing of cranioplasty has not been well established. OBJECTIVE To investigate whether the timing of cranioplasty is associated with differences in neurological outcome. METHODS A systematic literature review and meta-analysis was performed using MEDLINE, Scopus, and the Cochrane databases for studies reporting timing and neurological assessment for cranioplasty after decompressive craniectomy. Pre- and postcranioplasty neurological assessments for cranioplasty performed within (early) and beyond (late) 90 d were extracted. The standard mean difference (SMD) was used to normalize all neurological measures. Available data were pooled to compare pre-cranioplasty, postcranioplasty, and change in neurological status between early and late cranioplasty cohorts, and in the overall population. RESULTS Eight retrospective observational studies were included for a total of 528 patients. Studies reported various outcome measures (eg, Barthel Index, Karnofsky Performance Scale, Functional Independence Measure, Glasgow Coma Scale, and Glasgow Outcome Score). Cranioplasty, regardless of timing, was associated with significant neurological improvement (SMD .56, P = .01). Comparing early and late cohorts, there was no difference in precranioplasty neurological baseline; however, postcranioplasty neurological outcome was significantly improved in the early cohort (SMD .58, P = .04) and showed greater magnitude of change (SMD 2.90, P = .02). CONCLUSION Cranioplasty may improve neurological function, and earlier cranioplasty may enhance this effect. Future prospective studies evaluating long-term, comprehensive neurological outcomes will be required to establish the true effect of cranioplasty on neurological outcome.

Effects of Cranioplasty on Cerebral Blood Flow Following Decompressive Craniectomy: A Systematic Review of the Literature.

BACKGROUND Cranioplasty after decompressive craniectomy (DC) is routinely performed for reconstructive purposes and has been recently linked to improved cerebral blood flow (CBF) and neurological function. OBJECTIVE To systematically review all available literature to evaluate the effect of cranioplasty on CBF and neurocognitive recovery. METHODS A PubMed, Google Scholar, and MEDLINE search adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines included studies reporting patients who underwent DC and subsequent cranioplasty in whom cerebral hemodynamics were measured before and after cranioplasty. RESULTS The search yielded 21 articles with a total of 205 patients (range 3-76 years) who underwent DC and subsequent cranioplasty. Two studies enrolled 29 control subjects for a total of 234 subjects. Studies used different imaging modalities, including CT perfusion (n = 10), Xenon-CT (n = 3), single-photon emission CT (n = 2), transcranial Doppler (n = 6), MR perfusion (n = 1), and positron emission tomography (n = 2). Precranioplasty CBF evaluation ranged from 2 days to 6 months; postcranioplasty CBF evaluation ranged from 7 days to 6 months. All studies demonstrated an increase in CBF ipsilateral to the side of the cranioplasty. Nine of 21 studies also reported an increase in CBF on the contralateral side. Neurological function improved in an overwhelming majority of patients after cranioplasty. CONCLUSION This systematic review suggests that cranioplasty improves CBF following DC with a concurrent improvement in neurological function. The causative impact of CBF on neurological function, however, requires further study.

Effect of perioperative steroids on dysphagia after anterior cervical spine surgery: A systematic review

Background Dysphagia following anterior cervical spine surgery is common. Steroids potentially reduce post-operative inflammation that leads to dysphagia; however, the efficacy, optimal dose and route of steroid administration have not been fully elucidated. Objective The purpose of this systematic review is to evaluate the effect of peri-operative steroids on the incidence and severity of dysphagia following anterior cervical spine surgery. Methods A PubMed search adherent to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed to include clinical studies reporting use of steroids in adult patients following anterior cervical spine surgery. Data regarding steroid dose, route and timing of administration were abstracted. Incidence and severity of post-operative dysphagia were pooled across studies. Results Seven of 72 screened articles met inclusion criteria for a total of 246,298 patients that received steroids. Patients that received systemic and local steroids had significant reductions in rate and severity of dysphagia postoperatively. Reduction of dysphagia severity was more pronounced in patients undergoing multilevel procedures in both groups. There was no difference in infectious complications among patients that received steroids compared with controls. There was no difference in fusion rates at long-term follow-up. Conclusions and Clinical Relevance Steroids may reduce dysphagia after anterior cervical spinal procedures in the early post-operative period without increasing complications. This may be especially beneficial in patients undergoing multilevel procedures. Future studies should further define the optimal dose and route of steroid administration, and the specific contraindications for use.

Percutaneous Instrumentation Without Arthrodesis for Thoracolumbar Flexion-Distraction Injuries: A Review of the Literature

Background Flexion-distraction injuries (FDI) represent 5% to 15% of traumatic thoracolumbar fractures. Treatment depends on the extent of ligamentous involvement: osseous/Magerl type B2 injuries can be managed conservatively, while ligamentous/Magerl type B1 injuries undergo stabilization with arthrodesis. Minimally invasive surgery without arthrodesis can achieve similar outcomes to open procedures. This has been studied for burst fractures; however, its role in FDI is unclear. Objective To conduct a systematic review of the literature that examined minimally invasive surgery instrumentation without arthrodesis for traumatic FDI of the thoracolumbar spine. Methods Four electronic databases were searched, and articles were screened using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines for patients with traumatic FDI of the thoracolumbar spine treated with percutaneous techniques without arthrodesis and had postoperative follow-up. Results Seven studies with 44 patients met inclusion criteria. There were 19 patients with osseous FDI and 25 with ligamentous FDI. When reported, patients (n = 39) were neurologically intact preoperatively and at follow-up. Osseous FDI patients underwent instrumentation at 2 levels, while ligamentous injuries at approximately 4 levels. Complication rate was 2.3%. All patients had at least 6 mo of follow-up and demonstrated healing on follow-up imaging. Conclusion Percutaneous instrumentation without arthrodesis represents a low-risk intermediate between conservative management and open instrumented fusion. This “internal bracing” can be used in osseous and ligamentous FDIs. Neurologically intact patients who do not require decompression and those that may not tolerate or fail conservative management may be candidates. The current level of evidence cannot provide official recommendations and future studies are required to investigate long-term safety and efficacy.

Role of Spinal Diffusion Tensor Imaging in Predicting Post-operative Outcome in Cervical Degenerative Pathologies

Introduction Predicting post-operative recovery after surgery for cervical spondylotic myelopathy (CSM) is challenging. The authors performed a systematic review of the literature evaluating the diagnostic ability of DTI in CSM, and its ability to predict post-operative outcome. Material and Methods A systematic PubMED search adherent to PRISMA guidelines included relevant clinical studies reporting use of DTI in adult humans undergoing operative management for CSM from 1980 onwards. Available data on pre-operative clinical status and imaging and post-operative clinical outcomes were abstracted. Results Six of 562 studies were eligible for detailed review. There were 112 patients with CSM and 45 healthy controls. Seventy-three (59.8%) underwent operative management with mean follow-up time 90–730 days. Fractional anisotropy (FA) was significantly lower in patients compared with controls across multiple studies, and correlated with pre-operative assessment (modified Japanese Outcome Assessment). FA and fiber tractography ratio (FTR) correlated with post-operative clinical assessments, with FA independently predicted surgical need and good outcome post-operatively. Conclusion DTI may be a valuable tool in identifying patients in need of surgical decompression and predicting post-operative outcome. Future prospective studies are required for choosing optimal DTI parameters, anatomic levels and acquisition techniques.