Najib E. El Tecle

A pilot study to assess the construct and face validity of the Northwestern Objective Microanastomosis Assessment Tool

OBJECTnMicrosurgical skills remain an integral component of neurosurgical education. There is a need for an objective scale to assess microsurgical skills. The objective of this study was to assess the face and construct validity of a bench training microanastomosis module and an objective assessment scale, i.e., the Northwestern Objective Microanastomosis Assessment Tool (NOMAT).nnnMETHODSnMedical students, neurosurgical residents, and postdoctoral research fellows at Northwestern University were enrolled in the study. Trainees were divided into 3 groups based on microsurgical experience: 1) experienced, 2) exposed, and 3) novices. Each trainee completed two end-to-end microanastomoses using a 1-mm and a 3-mm synthetic vessel. Two cameras were installed to capture procedural footage. One neurosurgeon blindly graded the performance of trainees using both objective and subjective methods to assess construct validity. Two neurosurgeons reviewed the contents of the simulation module to assess face validity.nnnRESULTSnTwenty-one trainees participated in the study, including 6 experienced, 6 exposed, and 9 novices. The mean NOMAT score for experienced trainees on the 1-mm module was 47.3/70 compared with 26.0/70 and 25.8/70 for exposed and novice trainees, respectively (p = 0.02). Using subjective grading, experienced trainees performed significantly better on the 1-mm module (64.2/100) compared with exposed or novice trainees (23.3/100 and 25.0/100, respectively; p = 0.02). No statistical difference between groups was noted for the 3-mm module with both NOMAT and subjective grading. Experienced trainees took less time to perform both tasks compared with the others.nnnCONCLUSIONSnFace and construct validities of the microanastomosis module were established. The scale and the microanastomosis module could help assess the microsurgical skills of neurosurgical trainees and serve as a basis for the creation of a microsurgical curriculum.

Timing of surgery in spinal cord injury

Study Design. A systematic review of the literature for clinical and preclinical evidence related to timing of decompression following spinal cord injury (SCI). Objective. A review of the literature in search of consensus on what constitutes the ideal time frame for surgical management of SCI. Summary of Background Data. Optimal timing for surgical management of SCI remains poorly defined. Despite multiple preclinical and clinical studies, there is still lack of consensus on the optimal time for surgery in SCI. Methods. We systematically reviewed the literature for clinical and preclinical evidence related to timing of decompression following SCI. For clinical studies, our review included papers published in English after January 1, 1990. For preclinical studies, we limited our review to papers published after January 2001. The OVID-Medline and Web of Science databases were reviewed for preclinical studies, and the OVID-Medline, Cochrane, and Embase databases were reviewed for clinical studies. Results. A total of 8792 preclinical articles were identified. Of those, only 14 met our inclusion criteria and were included in the analysis. A total of 25,190 clinical articles were identified. Of those, only 30 studies met our inclusion criteria and were included for analysis. Clinical studies reported on a total of 5236 patients, of whom 1665 underwent early decompression and 3571 underwent late decompression. There was significant variability in the definition of early and late decompression in both clinical and preclinical studies. Preclinical data were in favor of early decompression. From a clinical standpoint, there was only level II evidence proving safety and feasibility of early decompression with no definite evidence of improved outcome for any of the two groups. Conclusion. There is growing evidence in favor of early decompression following SCI. Early decompression was proven to be clinically safe and feasible, but there is still no definite proof that early decompression leads to improved outcomes. Level of evidence: 5

Management of spinal fractures in patients with ankylosing spondylitis

Ankylosing spondlylitis is a seronegative spondyloarthropathy that primarily affects the spinal column and sacroiliac joints. With disease progression autofusion of the spinal column takes place. This combined with the brittle bone quality make patients prone to fractures and spinal cord injury. The typical fracture pattern is extension type and involves all three columns. These fractures and injuries may involve the craniovertebral junction, the subaxial cervical spine, and the thoracolumbar spine. While at times these fractures are challenging to manage especially when they affect the elderly, there is evidence that supports long segment fixation and fusion. This article presents a narrative review on managing spinal fractures in patients with ankylosing spondylitis.

Risk factors and outcomes in thoracic stenosis with myelopathy: A single center experience

OBJECTIVEnIdentify risk factors predisposing to thoracic spinal stenosis and myelopathy (TS) and address treatment options and outcomes.nnnMETHODSnA retrospective review of our centers experience with TS over 10 years. Clinical and magnetic resonance imaging (MRI) data, surgical intervention and outcomes using Frankel and Japanese Orthopedic Association (JOA) scales were collected.nnnRESULTSnA total of 44 patients with TS were identified. There were 30 men and 14 women with a mean age±SD of 66±15years. Neurological performance was evaluated using the Frankel scale (A-E or 1-5), and JOA scale for myelopathy (0-11). Frankel scores (1-5) and JOA scores (0-11) on admission were 3.5±0.9 and 6.8±2.6 respectively. At follow-up, Frankel scores had improved to 4.1±0.8 (p=0.041) and JOA scores had improved to 8.3±2.4 (p=0.021). The presence on admission of increased signal from the cord on T2-weighted MRI was associated with lower Frankel and JOA scores (3.3±0.9, and 6.2±2.5 respectively) than in those with absent increased signal (4.0±0.4 and 8.6±2.1, p=0.02 and p=0.008 respectively). There were 4 complications, requiring exploration and debridement for dehiscence in 3 and an epidural hematoma in the fourth that necessitated evacuation, with a good outcome. A fifth patient underwent reoperation at the same level 18 months later for persistent stenosis.nnnCONCLUSIONnThoracic stenosis with myelopathy should be entertained in patients with myelopathy. Over half of our patients with TS were over the age of 70, and men outnumbered women by a ratio of 2:1. Nearly half the patients with TS had concomitant cervical and/or lumbar degenerative disease warranting surgery also. Increased signal intensity on T2-weighted MRI images correlated with lower Frankel and JOA scores compared to those without. Decompression for thoracic stenosis is associated with neurological improvement.

Use of a harvested radial artery graft with preservation of the vena comitantes to reduce spasm risk and improve graft patency for extracranial to intracranial bypass: Technical note

BACKGROUND AND SIGNIFICANCEnThe vessels of choice for cerebrovascular high-flow direct bypass procedures are the radial artery and the saphenous vein. Radial artery grafts have become favored over saphenous vein grafts because of higher patency rates and better size matching to appropriate recipient vessels. Radial grafts are prone to spasm however, and this may be seen in 4-10% of cases and can be associated with ischemic sequelae. The standard technique for radial artery harvest calls for complete separation of the artery from its adventitial attachments and associated venous network. There is reason to believe that this could contribute to spasm risk and possibly even thrombosis. Radial graft outcomes appear to be improved when the vena comitantes is preserved in cardiac and peripheral applications. We report the novel use of a harvested radial artery graft with preservation of its venae comitantes for extracranial to intracranial bypass.nnnCLINICAL PRESENTATIONnThe patient is a 59-year-old male who had a blunt head trauma with associated loss of consciousness and who was led to the incidental discovery of a large fusiform middle cerebral artery (MCA) aneurysm.nnnCONCLUSIONnPreservation of the vena comitantes when harvesting a radial arterial graft for bypass, along with dual (arterial and venous) anastomoses, and concomitant use of intra-operative vaso-dilatory maneuvers to prevent spasm, may improve overall graft patency and patient outcome.

Trans-Sulcal Endoport-Assisted Evacuation of Supratentorial Intracerebral Hemorrhage: Initial Single-Institution Experience Compared to Matched Medically Managed Patients and Effect on 30-Day Mortality

BACKGROUNDnThe surgical management of supratentorial intracerebral hemorrhages (ICH) remains controversial due to large trials failing to show clear benefits. Several minimally invasive techniques have emerged as an alternative to a conventional craniotomy with promising results.nnnOBJECTIVEnTo report our experience with endoport-assisted surgery in the evacuation of supratentorial ICH and its effects on outcome compared to matched medical controls.nnnMETHODSnRetrospective data were gathered of patients who underwent endoport-assisted evacuation between January 2014 and October 2016 by a single surgeon. Patients who were managed medically during the same period were matched to the surgical cohort. Previously published cohorts investigating the same technique were analyzed against the present cohort.nnnRESULTSnSixteen patients were identified and matched to 16 patients treated medically. Location, hemorrhage volume, and initial Glasgow Coma Scale (GCS) score did not differ significantly between the 2 cohorts. The mean volume reduction in the surgical cohort was 92.05% ± 7.05%. The improvement in GCS in the surgical cohort was statistically significant (7-13, P = .006). Compared to the medical cohort, endoport-assisted surgery resulted in a statistically significant difference in in-hospital mortality (6.25% vs 75.0%, P < .001) and 30-d mortality (6.25% vs 81.25%, P < .001). Compared to previously published cohorts, the present cohort had lower median preoperative GCS (7 vs 10, P = .02), but postoperative GCS did not differ significantly (13 vs 14, P = .28).nnnCONCLUSIONnEndoport-assisted surgery is associated with high clot evacuation and decreases 30-d mortality compared to a similar medical group.

The natural history of complete spinal cord injury: a pooled analysis of 1162 patients and a meta-analysis of modern data

OBJECTIVE The natural history of complete spinal cord injury (SCI) is poorly studied. The classically quoted rate of improvement or conversion for patients with American Spinal Injury Association (ASIA) grade A (ASIA A) injuries is 15%-20%; however, data supporting this rate are very limited. In this paper, the authors conducted a meta-analysis of modern data reporting on ASIA A patients and evaluated factors affecting the natural history of the disease. METHODS The authors conducted a systematic literature review of all randomized clinical trials (RCTs) and observational studies of patients with traumatic SCI. The Embase, MEDLINE, PubMed, Scopus, CINAHL, and Cochrane databases were reviewed for all studies reporting on SCI and published after 1992. A meta-analysis was conducted using the DerSimonian and Laird (random-effects) model with a summary odds ratio analysis. RESULTS Eleven RCTs and 9 observational studies were included in the final analysis. Overall, the 20 included studies reported on 1162 patients with ASIA A injuries. The overall conversion rate was 28.1%, with 327 of 1162 patients improving to at least ASIA B. The overall rate of conversion noted in cervical spine injuries was 33.3%, whereas that in thoracic injuries was 30.6%. Patients undergoing early surgery had a higher rate of conversion (46.1%) than patients undergoing late surgery (25%) (OR 2.31, 95% CI 1.08-4.96, p = 0.03). CONCLUSIONS The overall rate of conversion of ASIA A SCIs from pooled data of prospective trials and observational series is 28.1%. This rate of conversion is higher than what is reported in the literature. Early surgery is predictive of a higher conversion rate. However, there are not enough data to provide conclusions pertaining to the efficacy of biological and medical therapies.

C5 palsy following posterior decompression and instrumentation in cervical stenosis: Single center experience and review

OBJECTIVEnCausation and avoidance of C5 palsy after laminectomy have proven elusive, with multiple factors incriminated including width of the laminectomy, spinal cord migration, C5 neural foraminal stenosis, or intraoperative C5 root traction. In an attempt to identify risk factors for C5 palsy after decompression in cervical stenosis and myelopathy, the following review was conducted. This report is from a single center with consistent criteria for diagnosis and management of cervical stenosis and myelopathy.nnnPATIENTS AND METHODSnWe retrospectively reviewed 63 patients with cervical stenosis and myelopathy who had been treated with laminectomy with instrumentation at the C4-6 level. Imaging studies reviewed included plain X-ray films, magnetic resonance imaging (MRI), and computed tomography (CT) scans of the cervical spine. Health-related outcomes were assessed before and at follow-up and included Visual Analog Scale (VAS) for pain (1-10), Japanese Orthopedic Association (JOA) score for myelopathy (0-18), and SF-36 physical functioning, energy and fatigue, and general health categories (0-100).nnnRESULTSnIn 53 patients (control group), decompression and instrumentation was accomplished without incident, but 5 patients developed lasting postoperative C5 palsy. At follow-up, there were overall significant improvements in VAS, JOA, and SF-36 physical functioning and general health domains. Subsequent to surgery, a loss of lordosis of 5° and an increase in C2 sagittal vertical axis (SVA) of 17u2009mm was significant. There was, however, no significant difference between control and C5 palsy patients in lordosis and C2 SVA, before or after surgery. Postoperative MRI studies were obtained in 15 of the control patients and 6 of the C5 palsy patients. Postoperative width of the laminectomy as well as the caliber of the C5 neural foramina in the control and C5 palsy cohorts were not statistically different. Though the posterior displacement of the cord in the C5 palsy cohort was larger than in controls, this difference was also not significant.nnnCONCLUSIONnThe above findings suggest that the cause of C5 palsy remains elusive. Though our incidence of lasting C5 palsy subsequent to laminectomy and instrumentation was 8%, it is probably under-reported. In our experience, laminectomy and instrumentation failed to increase lordosis and, in fact, were associated with an increase in positive cervical balance. Complications with cervical laminectomy and instrumentation are not by any means rare, and need to be emphasized in counselling patients, and selecting the approach.

Programmable shunt valve interactions with osseointegrated hearing devices

OBJECTIVE Patients with ventriculoperitoneal (VP) shunts with programmable valves who would benefit from osseointegrated hearing devices (OIHDs) represent a unique population. The aim of this study was to evaluate the magnetic field strengths of 4 OIHDs and their interactions with 5 programmable VP shunt valves. METHODS Magnetic field strength was measured as a function of distance for each hearing device (Cochlear Baha 5, Cochlear Baha BP110, Oticon Ponto Plus Power, and Medtronic Sophono) in the following modes: inactive, active in quiet, and active in 60 decibels of background noise in the sound booth. The hearing devices were introduced to each shunt valve (Aesculap proGAV, Aesculap proGAV 2.0, Codman Hakim, Codman Certas, and Medtronic Strata II) also as a function of distance in these identical 3 settings. Each trial was repeated 5 times. Between each trial, the valves were assessed for a change in setting. Finally, using a skull model, the devices were introduced to each other in standard anatomical locations and the valves were assessed for a change in settings. RESULTS The maximum magnetic field strengths generated by the Cochlear Baha 5, BP110, and Oticon OIHDs were 1.1, 36.2, and 48.7 gauss (G), respectively. The maximum strength generated by the Sophono device was > 800 G. The magnetic field strength of the hearing devices decreased markedly with increasing distance from the device. The strength of the Sophonos magnetic attachment decreased to 34.8 G at 5 mm. The Codman Hakim, Codman Certas, and Medtronic Strata II valve settings changed when rotating the valves next to the Sophono abutment. No other changes in valve settings occurred in the distance or anatomical models for any other trials. CONCLUSIONS This is the first study evaluating the interaction between OIHDs and programmable VP shunt valves. The findings suggest that it is safe to use these devices together without having to switch to a nonprogrammable valve or move the shunt valve to a more distant location. Still, care should be taken if the Sophono device is used to ensure that the valve is ≥ 5 mm away from the magnetic attachment.

Management of concomitant scoliosis and tethered cord syndrome in non-spina bifida pediatric population

BackgroundThe management of concomitant scoliosis and tethered cord syndrome in the non-spina bifida pediatric population is challenging. In the present study, we evaluate the efficacy of different treatment modalities and propose a treatment plan for the management of affected patients.MethodsA systematic literature review was conducted by querying the MEDLINE, PubMed, Cochrane, EMBASE, Scopus, and Web of Science databases for papers published between January 1996 and June 2016 and reporting on concomitant scoliosis and tethered cord. We excluded animal studies, non-English papers as well as papers reporting on patients with multiple concomitant intraspinal anomalies such as spina bifida.ResultsOut of 1993 articles, only 13 met our inclusion criteria. These 13 articles described six main management approaches: Observation, cord untethering only, cord untethering followed by deformity correction, simultaneous cord untethering and deformity correction, and deformity correction without untethering. Selection of the best approach is a function of the patient’s symptomatology and Cobb angle.ConclusionWe propose treatment plan for the management of patients with concomitant tethered cord syndrome and spinal deformity. Asymptomatic patients can be followed conservatively and managed as scoliosis patients with no need for untethering. Surgical management in a staged fashion seems appropriate in symptomatic patients with a Cobb angle less than 35°. In these patients, deformity can improve following untethering, thus sparing the patient the risks of surgical correction of scoliosis. Staged or non-staged cord untethering and curve correction seem to be adequate in symptomatic patients with Cobb angle >35° as these patients are likely to require both untethering and deformity correction.