Benjamin Zussman

Early Complications Related to Approach in Cervical Spine Surgery: Single-Center Prospective Study

BACKGROUND Surgical intervention is performed on the cervical spine in a heterogeneous number of pathologic conditions in a diverse patient population. Several authors have examined complication prevalence in cervical spine surgery using retrospective analysis. However, few prospective studies have directly examined perioperative complications. Most prospective studies in the spine literature have assessed only specific spinal implants in carefully selected surgical patients, and complication incidence in broader patient populations is limited. OBJECTIVES To prospectively collect data on all patients who underwent cervical spine surgery at a large tertiary care center and to evaluate the effect of the approach and the incidence of early complications. METHODS Data were collected prospectively on 119 patients admitted to the neurosurgical service at Thomas Jefferson University hospital from May to December 2008. Data collected consisted of preoperative diagnosis, medical comorbidities, body mass index, surgical approach, length of stay, and complications, and were analyzed using multivariate regression analysis. Complications occurring within 30 days after each operative procedure were included. Medical adverse events, regardless of their relationship to the operative intervention, were also included as complications. A previously validated binary definition of major and minor complications was used to stratify the data. RESULTS Overall, 53 of 119 patients (44.5%) experienced at least one complication. Eleven of 41 patients (26.8%) undergoing only an anterior cervical procedure had a perioperative complication, compared with 26 of 53 patients (49.0%) undergoing only a posterior cervical procedure (P = .01). In patients undergoing a combined anterior and posterior surgical procedure, 16 of 25 (66%) experienced a complication, a significant difference in comparison with solitary anterior procedures (P = .004). Anterior procedures were associated with postoperative dysphagia and vocal cord paresis, whereas wound infection and C5 palsy was more frequently recorded in the group undergoing surgery via an isolated posterior approach. CONCLUSIONS The incidence of complications or adverse events is not definitely known for most spinal procedures because of the complexity of defining complications and obtaining accurate data. Therefore, to obtain a more accurate assessment of spinal procedures, a prospective algorithm was designed to collect and record complications during the acute perioperative period. Using this technique, a significantly higher complication rate was documented than had been previously reported for cervical spine operative interventions. In addition, use of a broad definition of perioperative complications likely increased the recorded incidence of perioperative adverse events and complications. Complications were more common in patients undergoing posterior and anteroposterior procedures.

The relative effect of vendor variability in CT perfusion results: a method comparison study.

OBJECTIVE There are known interoperator, intraoperator, and intervendor software differences that can influence the reproducibility of quantitative CT perfusion values. The purpose of this study was to determine the relative impact of operator and software differences in CT perfusion variability. MATERIALS AND METHODS CT perfusion imaging data were selected for 11 patients evaluated for suspected ischemic stroke. Three radiologists each independently postprocessed the source data twice, using four different vendor software applications. Results for cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) were recorded for the lentiform nuclei in both hemispheres. Repeated variables multivariate analysis of variance was used to assess differences in the means of CBV, CBF, and MTT. Bland-Altman analysis was used to assess agreement between pairs of vendors, readers, and read times. RESULTS Choice of vendor software, but not interoperator or intraoperator disagreement, was associated with significant variability (p < 0.001) in CBV, CBF, and MTT. The mean difference in CT perfusion values was greater for pairs of vendors than for pairs of operators. CONCLUSION Different vendor software applications do not generate quantitative perfusion results equivalently. Intervendor difference is, by far, the largest cause of variability in perfusion results relative to interoperator and intraoperator difference. Caution should be exercised when interpreting quantitative CT perfusion results because these values may vary considerably depending on the postprocessing software.

Sources of variability in computed tomography perfusion: implications for acute stroke management

OBJECT Although dynamic, first-pass cerebral CT perfusion is used in the evaluation of acute ischemic stroke, a lack of standardization restricts the value of this imaging modality in clinical decision-making. The purpose of this study was to comprehensively review the reported sources of variability and error in cerebral CT perfusion results. METHODS A systematic literature review was conducted, 120 articles were reviewed, and 23 published original research articles were included. Sources of variability and error were thematically categorized and presented within the context of the 3 stages of a typical CT perfusion study: data acquisition, postprocessing, and results interpretation. RESULTS Seven factors that caused variability were identified and described in detail: 1) contrast media, the iodinated compound injected intravascularly to permit imaging of the cerebral vessels; 2) data acquisition rate, the number of images obtained by CT scan per unit time; 3) user inputs, the subjective selections that operators make; 4) observer variation, the failure of operators to repeatedly measure a perfusion parameter with precision; 5) software operational mode, manual, semiautomatic, or automatic; 6) software design, the mathematical algorithms used to perform postprocessing; and 7) value type, absolute versus relative values. CONCLUSIONS Standardization at all 3 stages of the CT perfusion study cycle is warranted. At present, caution should be exercised when interpreting CT perfusion results as these values may vary considerably depending on a variety of factors. Future research is needed to define the role of CT perfusion in clinical decision-making for acute stroke patients and to determine the clinically acceptable limits of variability in CT perfusion results.

The incidence of pulmonary embolism (PE) after spinal fusions

BACKGROUND Pulmonary embolism (PE) is a rare but serious event that may occur after spinal surgery. OBJECTIVE To correlate PE incidence after spinal arthrodesis with surgical approach, region of spine operated, and primary spinal pathology. To identify PE incidence trends in this population. METHODS The Nationwide Inpatient Sample was queried using ICD-9 codes (81.01-81.08) for spinal fusion procedures over a 21-year period (1988-2008). Other data points included PE occurrence, surgical approach, spinal region, surgical indication, and mortality. Multivariate and relational analyses were performed. RESULTS 4,505,556 patients were identified and 9530 had PE (incidence=0.2%). PE patients had higher odds of combined A/P surgical approaches than posterior approaches (OR=1.97; 95% CI=1.66-2.33), and PE incidence was higher in thoracic versus cervical or lumbar fusions (OR=2.54; 95% CI=2.14-3.02). PE was more likely with vertebral fracture (OR=1.85; 95% CI=1.53-2.23) and SCI with vertebral fracture (OR=4.59; 95% CI=3.72-5.70) than without trauma. Between 1988 and 2008, the PE incidence remained stable for patients with intervertebral disk degeneration and scoliosis, but increased for patients with vertebral fracture, and SCI with vertebral fracture. There was greater inpatient mortality with occurrence of a PE (OR=12.92; 95% CI=10.55-14.41). CONCLUSION Although the incidence of PE in spinal arthrodesis patients is only 0.2%, there is a higher incidence after combined A/P approaches, thoracic procedures, and trauma surgical procedures. Despite the overall PE incidence remaining stable since 1988, incidence steadily increased among trauma patients. Further research is needed to explain these trends, given the context of changing patient populations and improving surgical techniques and prophylaxis measures. Greater caution and prophylaxis among trauma patients may be warranted.

Stereotactic radiosurgery for intradural spine tumors using cone-beam CT image guidance

OBJECTIVE Cone-beam CT (CBCT) image guidance technology has been widely adopted for spine radiosurgery delivery. There is relatively little experience with spine radiosurgery for intradural tumors using CBCT image guidance. This study prospectively evaluated a series of intradural spine tumors treated with radiosurgery. Patient setup accuracy for spine radiosurgery delivery using CBCT image guidance for intradural spine tumors was determined. METHODS Eighty-two patients with intradural tumors were treated and prospectively evaluated. The positioning deviations of the spine radiosurgery treatments in patients were recorded. Radiosurgery was delivered using a linear accelerator with a beam modulator and CBCT image guidance combined with a robotic couch that allows positioning correction in 3 translational and 3 rotational directions. To measure patient movement, 3 quality assurance CBCTs were performed and recorded in 30 patients: before, halfway, and after the radiosurgery treatment. The positioning data and fused images of planning CT and CBCT from the treatments were analyzed to determine intrafraction patient movements. From each of 3 CBCTs, 3 translational and 3 rotational coordinates were obtained. RESULTS The radiosurgery procedure was successfully completed for all patients. Lesion locations included cervical (22), thoracic (17), lumbar (38), and sacral (5). Tumor histologies included schwannoma (27), neurofibromas (18), meningioma (16), hemangioblastoma (8), and ependymoma (5). The mean prescription dose was 17 Gy (range 12-27 Gy) delivered in 1-3 fractions. At the halfway point of the radiation, the translational variations and standard deviations were 0.4 ± 0.5, 0.5 ± 0.8, and 0.4 ± 0.5 mm in the lateral (x), longitudinal (y), and anteroposterior (z) directions, respectively. Similarly, the variations immediately after treatment were 0.5 ± 0.4, 0.5 ± 0.6, and 0.6 ± 0.5 mm along x, y, and z directions, respectively. The mean rotational angles were 0.3° ± 0.4°, 0.3° ± 0.4°, and 0.3° ± 0.4° along yaw, roll, and pitch, respectively, at the halfway point and 0.5° ± 0.5°, 0.4° ± 0.5°, and 0.2° ± 0.3° immediately after treatment. CONCLUSIONS Radiosurgery offers an alternative treatment option for intradural spine tumors in patients who may not be optimal candidates for open surgery. CBCT image guidance for patient setup for spine radiosurgery is accurate and successful in patients with intradural tumors.

Anterograde Revision of Cervical Spinal Cord Stimulator Paddle Electrode: A Case Report

Objectives:  To illustrate a new surgical revision strategy for malfunctioning spinal cord stimulation (SCS) paddle electrodes.

Use of Pipeline Endovascular Device in Patients with Nickel Allergies

BACKGROUND Metal allergies affect a significant portion of the population; intracranial flow diverters contain many of the most commonly allergenic metals. Prior literature has suggested patch testing for all patients with documented or suspected metal allergies before intracranial flow diverter placement; however, there remains a paucity of reports of patients with documented metal allergies undergoing intracranial flow diversion. CASE DESCRIPTION We report 2 patients with documented nickel allergies, confirmed via patch testing by a board-certified allergist, and unruptured intracranial aneurysms that underwent treatment with the PED. Both patients developed contact dermatitis when a PED was affixed to their skin during their preoperative workup. Follow-up arteriography at 12 and 36 months post PED placement showed no evidence of in-stent stenosis or intimal hyperplasia, and both patients never developed systemic allergic reactions. CONCLUSIONS In 2 patients with known nickel allergies and intracranial aneurysms treated with the PED, there were no clinically or radiographically apparent allergic reactions at greater than 2 years of follow-up.

Seeing Is Believing: Headway27 as a Highly Visible and Versatile Microcatheter with Ideal Dimensions for Stroke Thrombectomy

Introduction: Microcatheter selection is an infrequent focus of stroke thrombectomy technique evaluation. The Headway27 microcatheter strikes an excellent balance of microcatheter dimensions (156 cm length, 2.6 Fr distal OD, ID 0.027 inches) and visibility, making it ideal for stroke thrombectomy. Methods: We evaluated a prospectively maintained acute stroke thrombectomy database containing 50 consecutive cases using the Headway27 microcatheter. From the database, patient demographics, clinical and angiographic information as well as procedural technical details and complications were extracted. Results: Manual aspiration thrombectomy (MAT) was performed alone in 72% of cases, stentriever-assisted MAT was performed in 6% of cases, and a combination was used in 22% of cases. Median groin puncture to final recanalization time was 27 min and mTICI 2B/3 recanalization was achieved in 94% of cases. There were 2 intra-procedural complications, neither related to the microcatheter. In all cases, the Headway27 reached the intended target vessel: M1 (n = 4), M2 (n = 26), M3 (n = 13), P2 (n = 3), P3 (n = 1), and basilar artery (n = 3). There were no cases requiring usage of an additional or alternative microcatheter. In 45/47 cases of MAT, the reperfusion catheter tracked over the Headway to the clot/intended target; in two cases, the microcatheter was used to deploy a stentriever that then allowed the reperfusion catheter to track to the clot. Conclusion: The Headway27 microcatheter reliably facilitated rapid clot access in anterior and posterior circulation acute large vessel occlusions with no microcatheter-associated complications.

Cervical instability presenting as thoracic pain: Case report and literature review

Abstract Study design Case report. Objective To report a case of cervical instability from an os odontoideum that presented as posterior thoracic pain and to present a review of the literature. Background Thoracic posterior paraspinal spasms and pain are common chief complaints in individuals with spinal abnormalities. Methods A 19-year-old man presented with posterior thoracic pain for nearly 1 year following a college sports-related injury (lacrosse). Computed tomography and magnetic resonance imaging did not reveal any significant thoracic or lumbar spinal cord or nerve root pathology, but did reveal an incidental finding of an os odontoideum. Results Surgical stabilization of the atlantoaxial instability resulting from the os odontoideum resulted in complete resolution of the patients thoracic pain. Conclusions Thoracic back pain without a clear thoracic spine etiology warrants further workup to rule out the possibility of spinal instability.