Utilization of Locum Tenens in Neurosurgery.

INTRODUCTION: Despite its rising popularity, little has been described about locum tenens employment (locums) in neurosurgery. This study provides the first nationwide overview of the locums neurosurgery experience. METHODS: An anonymous online survey examined practice characteristics of respondents, extent of and satisfaction with locums, motivations for pursuing locums, case volumes, agencies used, compensation, and positive/negative aspects of experiences. Responses were collected between November 2020 and February 2021. RESULTS: Response rate for the 1852 neurosurgeons who opened the survey request was 4.9%; 36 of 91 respondents had previously worked locums and were commonly motivated by compensation or transitioning to new jobs or retirement. In our response group, 92% of locums respondents had taken more than one position and 47% had taken more than 10. Neurosurgeons performing <200 cases/year were significantly more likely to have also worked locums than those performing >200 cases/year (41.6% locums, 12.7% non-locums, P = 0.001). Responses showed that 69% of locums respondents earned $2000-$2999/day and 16% earned >$3500/day. Nearly 78% of locums respondents were satisfied with their experience(s) and 86% would take another future locums position. Being in practice for >15 years was significantly associated with satisfaction with locums (P = 0.03). Reported flaws included unfamiliarity with hospitals, limited continuity of care, credentialing burdens, and inadequate travel compensation. CONCLUSIONS: Locums is utilized by neurosurgeons across multiple practice types and may serve to complement workloads or "fill in gaps" between longer-term employment. Overall, locums neurosurgeons are well compensated, and the majority are satisfied with their experience(s). Inevitably, flaws still exist with locums employment, which may be the focus of organized efforts aiming to improve the experience.

Is Minimally Invasive Spinal Surgery Superior to Endoscopic Spine Surgery in Postoperative Radiologic Outcomes of Lumbar Spine Degenerative Disease? A Systematic Review.

BACKGROUND: Minimally invasive spinal surgery (ESS) are both well-established surgical techniques for lumbar spinal stenosis; however, there is limited literature comparing the efficacy of the two techniques with respect to radiologic decompression data. METHODS: In this review, PubMed, Google Scholar, and Scopus databases were systematically searched from inception until July 2022 for studies that reported the radiologic outcomes of endoscopic and minimally invasive approaches for decompressive spinal surgery, namely, the spinal canal area, neural foraminal area, and neural foraminal heights. RESULTS: Of the 378 articles initially retrieved using MeSH and keyword search, 9 studies reporting preoperative and postoperative spinal areas and foraminal areas and heights were finally included in our review. Of the total 581 patients, 391 (67.30%) underwent MISS and 190 (32.70%) underwent ESS. The weighted mean difference between the spinal canal diameter in pre- and postoperative conditions was 56.64 ± 7.11 and 79.52 ± 21.31 mm2 in the MISS and ESS groups, respectively. ESS was also associated with a higher mean difference in the foraminal area postoperatively (72 ± 1 vs. 35.81 ± 11.3 mm2 in the MISS and ESS groups, respectively), but it was comparable to MISS in terms of the foraminal height (0.32 ± 0.037 vs. 0.29 ± 0.03 cm in the MISS and endoscopic groups, respectively). CONCLUSIONS: Compared with MISS, ESS was associated with improved radiologic parameters, including spinal canal area and neural foraminal area in the lumbar spinal segments. Both techniques led to the same endpoint of neural decompression when starting with a more severe compression. However, the present data do not allow the correlation of the radiographic results with the related clinical outcomes.

Utilization of Dual Expandable Cages in Lateral Lumbar Interbody Fusion Surgery.

The aim of this study is to present a case series of adult patients with lumbar degenerative scoliosis who underwent focused minimally invasive spine (MIS) surgery utilizing a new dual expandable cage technology. The study investigates the effectiveness of this approach in reducing the symptoms and progression of lumbar degenerative scoliosis (LDS). Adult patients with lumbar degenerative scoliosis were selected for focused MIS using the newly introduced expandable cage technology. Patient demographics, preoperative evaluations, surgical details, and postoperative outcomes were recorded. The primary outcome measures included the restoration of disc space height, an improvement in clinical outcomes, and a reduction in surgical complications. Analysis of the case series reveals promising outcomes following focused MIS with the utilization of the new expandable cage technology. The technique demonstrated successful restoration of intervertebral disc space heights and improved clinical outcomes in patients with lumbar degenerative scoliosis. Furthermore, a notable reduction in surgical complications was observed. The findings from this case series suggest that MIS with the implementation of the new expandable cage technology holds promise for patients with lumbar degenerative scoliosis. This approach appears to have the potential to effectively restore disc space heights, improve clinical outcomes, and minimize surgical complications. Here, we want to emphasize and add details to the improved clinical outcomes of this technology; however, further research and larger prospective studies are warranted to validate these preliminary results and establish the long-term benefits and safety profile of this innovative technique.

Radiation Myelopathy: A Case Report and Literature Review.

Proton beam therapy is a common type of radiation treatment that delivers a beam of proton particles to treat cancer and minimize damage to nearby healthy tissue. In this paper, we describe a case of a 20-year-old male patient with osteosarcoma of the distal right femur that eventually metastasized to his thoracic cavity. The patient underwent radiation beam therapy treatment that was directed at his left thorax and nine months later presented with clinical and radiographic findings of delayed radiation myelopathy (RM).

A Proposed Personalized Spine Care Protocol (SpineScreen) to Treat Visualized Pain Generators: An Illustrative Study Comparing Clinical Outcomes and Postoperative Reoperations between Targeted Endoscopic Lumbar Decompression Surgery, Minimally Invasive TLIF and Open Laminectomy.

Background: Endoscopically visualized spine surgery has become an essential tool that aids in identifying and treating anatomical spine pathologies that are not well demonstrated by traditional advanced imaging, including MRI. These pathologies may be visualized during endoscopic lumbar decompression (ELD) and categorized into primary pain generators (PPG). Identifying these PPGs provides crucial information for a successful outcome with ELD and forms the basis for our proposed personalized spine care protocol (SpineScreen). Methods: a prospective study of 412 patients from 7 endoscopic practices consisting of 207 (50.2%) males and 205 (49.8%) females with an average age of 63.67 years and an average follow-up of 69.27 months was performed to compare the durability of targeted ELD based on validated primary pain generators versus image-based open lumbar laminectomy, and minimally invasive lumbar transforaminal interbody fusion (TLIF) using Kaplan-Meier median survival calculations. The serial time was determined as the interval between index surgery and when patients were censored for additional interventional and surgical treatments for low back-related symptoms. A control group was recruited from patients referred for a surgical consultation but declined interventional and surgical treatment and continued on medical care. Control group patients were censored when they crossed over into any surgical or interventional treatment group. Results: of the 412 study patients, 206 underwent ELD (50.0%), 61 laminectomy (14.8%), and 78 (18.9%) TLIF. There were 67 patients in the control group (16.3% of 412 patients). The most common surgical levels were L4/5 (41.3%), L5/S1 (25.0%), and L4-S1 (16.3%). At two-year f/u, excellent and good Macnab outcomes were reported by 346 of the 412 study patients (84.0%). The VAS leg pain score reduction was 4.250 ± 1.691 (p < 0.001). No other treatment during the available follow-up was required in 60.7% (125/206) of the ELD, 39.9% (31/78) of the TLIF, and 19.7% (12/61 of the laminectomy patients. In control patients, only 15 of the 67 (22.4%) control patients continued with conservative care until final follow-up, all of which had fair and poor functional Macnab outcomes. In patients with Excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients (p < 0.001). The overall survival time in control patients was eight months with a standard error of 0.942, a lower boundary of 6.154, and an upper boundary of 9.846 months. In patients with excellent Macnab outcomes, the median durability was 62 months in ELD, 43 in TLIF, and 31 months in laminectomy patients versus control patients at seven months (p < 0.001). The most common new-onset symptom for censoring was dysesthesia ELD (9.4%; 20/206), axial back pain in TLIF (25.6%;20/78), and recurrent pain in laminectomy (65.6%; 40/61) patients (p < 0.001). Transforaminal epidural steroid injections were tried in 11.7% (24/206) of ELD, 23.1% (18/78) of TLIF, and 36.1% (22/61) of the laminectomy patients. The secondary fusion rate among ELD patients was 8.8% (18/206). Among TLIF patients, the most common additional treatments were revision fusion (19.2%; 15/78) and multilevel rhizotomy (10.3%; 8/78). Common follow-up procedures in laminectomy patients included revision laminectomy (16.4%; 10/61), revision ELD (11.5%; 7/61), and multilevel rhizotomy (11.5%; 7/61). Control patients crossed over into ELD (13.4%), TLIF (13.4%), laminectomy (10.4%) and interventional treatment (40.3%) arms at high rates. Most control patients treated with spinal injections (55.5%) had excellent and good functional outcomes versus 40.7% with fair and poor (3.7%), respectively. The control patients (93.3%) who remained in medical management without surgery or interventional care (14/67) had the worst functional outcomes and were rated as fair and poor. Conclusions: clinical outcomes were more favorable with lumbar surgeries than with non-surgical control groups. Of the control patients, the crossover rate into interventional and surgical care was 40.3% and 37.2%, respectively. There are longer symptom-free intervals after targeted ELD than with TLIF or laminectomy. Additional intervention and surgical treatments are more often needed to manage new-onset postoperative symptoms in TLIF- and laminectomy compared to ELD patients. Few ELD patients will require fusion in the future. Considering the rising cost of surgical spine care, we offer SpineScreen as a simplified and less costly alternative to traditional image-based care models by focusing on primary pain generators rather than image-based criteria derived from the preoperative lumbar MRI scan.

A Case Series of Permanent Dorsal Root Ganglion Stimulation.

Introduction  Neuropathic pain commonly causes high levels of pain that impairs multiple facets of the lives of patients. Multiple first-line treatments such as physical therapy and pharmacological intervention exist. Treatment refractory to these interventions may be considered for spinal cord stimulation (SCS). However, modest rates of meaningful relief leave room for improvement. Dorsal root ganglion stimulation (DRGS) has been touted to be a viable alternative solution to SCS with more specific targets and, consequently, fewer side effects. Thus, DRGS has been accepted as a better alternative to spinal cord stimulation. In contrast, we report a series of DRGS patients who had lower rates of meaningful pain relief than what was reported in the literature. Methods We present a series of 11 patients who underwent both DRGS trial and subsequent permanent implantation with negative outcomes (defined by ≥ 50% of pre-surgical pain) in 55% of patients. Patient records were searched for comorbidities that could potentially affect the DRGS implant (diabetes, cancer, smoking, age > 70 years old). Once delineated, the predictive value of each comorbidity for negative outcomes was estimated. Results Eighteen patients had a successful DRGS trial which was defined as a ≥ 50% pain reduction as well as increased ability to perform daily activities. Seven patients elected not to proceed with the permanent DRGS. Of the 11 remaining patients that had the permanent DRGS, four patients reported being completely pain-free ≥ one month following implantation, one reported a significant increase in pain improvement at four months post-operation, and six patients reported pain that was ≥ 50% of their pre-surgical pain 4-12 months following implantation.  Conclusion In our case series, we observed a discrepancy between DRGS trial outcomes and outcomes following permanent implantation. We found that a stronger correlation may exist between worse outcomes and smoking. Older age, the presence of diabetes, and cancer had more modest associations. These comorbidities may have value as tests for predicting negative outcomes of permanent DRGS implantation. Additionally, we hypothesized that this could also be due to the presence of psychological factors which obscure the true result of the DRGS trial. Thus, we suggest that DRGS be prescribed with caution in these patient populations, and use comorbidities to test for the likelihood of negative outcomes. Limitations of this study are those that are intrinsic to a retrospective case series.

A Proposed Brain-, Spine-, and Mental- Health Screening Methodology (NEUROSCREEN) for Healthcare Systems: Position of the Society for Brain Mapping and Therapeutics.

The COVID-19 pandemic has accelerated neurological, mental health disorders, and neurocognitive issues. However, there is a lack of inexpensive and efficient brain evaluation and screening systems. As a result, a considerable fraction of patients with neurocognitive or psychobehavioral predicaments either do not get timely diagnosed or fail to receive personalized treatment plans. This is especially true in the elderly populations, wherein only 16% of seniors say they receive regular cognitive evaluations. Therefore, there is a great need for development of an optimized clinical brain screening workflow methodology like what is already in existence for prostate and breast exams. Such a methodology should be designed to facilitate objective early detection and cost-effective treatment of such disorders. In this paper we have reviewed the existing clinical protocols, recent technological advances and suggested reliable clinical workflows for brain screening. Such protocols range from questionnaires and smartphone apps to multi-modality brain mapping and advanced imaging where applicable. To that end, the Society for Brain Mapping and Therapeutics (SBMT) proposes the Brain, Spine and Mental Health Screening (NEUROSCREEN) as a multi-faceted approach. Beside other assessment tools, NEUROSCREEN employs smartphone guided cognitive assessments and quantitative electroencephalography (qEEG) as well as potential genetic testing for cognitive decline risk as inexpensive and effective screening tools to facilitate objective diagnosis, monitor disease progression, and guide personalized treatment interventions. Operationalizing NEUROSCREEN is expected to result in reduced healthcare costs and improving quality of life at national and later, global scales.

Neuroscience20 (BRAIN20, SPINE20, and MENTAL20) Health Initiative: A Global Consortium Addressing the Human and Economic Burden of Brain, Spine, and Mental Disorders Through Neurotech Innovations and Policies.

Neurological disorders significantly impact the world's economy due to their often chronic and life-threatening nature afflicting individuals which, in turn, creates a global disease burden. The Group of Twenty (G20) member nations, which represent the largest economies globally, should come together to formulate a plan on how to overcome this burden. The Neuroscience-20 (N20) initiative of the Society for Brain Mapping and Therapeutics (SBMT) is at the vanguard of this global collaboration to comprehensively raise awareness about brain, spine, and mental disorders worldwide. This paper aims to provide a comprehensive review of the various brain initiatives worldwide and highlight the need for cooperation and recommend ways to bring down costs associated with the discovery and treatment of neurological disorders. Our systematic search revealed that the cost of neurological and psychiatric disorders to the world economy by 2030 is roughly $16T. The cost to the economy of the United States is $1.5T annually and growing given the impact of COVID-19. We also discovered there is a shortfall of effective collaboration between nations and a lack of resources in developing countries. Current statistical analyses on the cost of neurological disorders to the world economy strongly suggest that there is a great need for investment in neurotechnology and innovation or fast-tracking therapeutics and diagnostics to curb these costs. During the current COVID-19 pandemic, SBMT, through this paper, intends to showcase the importance of worldwide collaborations to reduce the population's economic and health burden, specifically regarding neurological/brain, spine, and mental disorders.

COVID-19: Review of a 21st Century Pandemic from Etiology to Neuro-psychiatric Implications.

COVID-19 is a severe infectious disease that has claimed >150,000 lives and infected millions in the United States thus far, especially the elderly population. Emerging evidence has shown the virus to cause hemorrhagic and immunologic responses, which impact all organs, including lungs, kidneys, and the brain, as well as extremities. SARS-CoV-2 also affects patients', families', and society's mental health at large. There is growing evidence of re-infection in some patients. The goal of this paper is to provide a comprehensive review of SARS-CoV-2-induced disease, its mechanism of infection, diagnostics, therapeutics, and treatment strategies, while also focusing on less attended aspects by previous studies, including nutritional support, psychological, and rehabilitation of the pandemic and its management. We performed a systematic review of >1,000 articles and included 425 references from online databases, including, PubMed, Google Scholar, and California Baptist University's library. COVID-19 patients go through acute respiratory distress syndrome, cytokine storm, acute hypercoagulable state, and autonomic dysfunction, which must be managed by a multidisciplinary team including nursing, nutrition, and rehabilitation. The elderly population and those who are suffering from Alzheimer's disease and dementia related illnesses seem to be at the higher risk. There are 28 vaccines under development, and new treatment strategies/protocols are being investigated. The future management for COVID-19 should include B-cell and T-cell immunotherapy in combination with emerging prophylaxis. The mental health and illness aspect of COVID-19 are among the most important side effects of this pandemic which requires a national plan for prevention, diagnosis and treatment.

Metastatic Intracerebral Chondrosarcoma: Case Report and Literature Review of Endocrine Effects and Management Paradigms.

The most common underlying diagnosis of intracranial tumor pathology is metastatic disease, followed by primary brain tumors. Chondrosarcomatous metastatic disease of the brain is a rare subtype of this disease process. The patient presented with right-sided weakness. Her history was significant for femur chondrosarcoma which was resected and treated. Laboratory analysis revealed persistent hypercalcemia and hyperglycemia. MRI of the brain was completed, which revealed a left parietal-occipital lesion with smaller lesions in the left frontal and right parietal lobe. Multidisciplinary tumor board recommended surgery for lesion resection and pathology. Surgical pathologic diagnosis after lesion resection was metastatic chondrosarcoma. The patient's preoperative arm and leg weakness improved after surgery. Our paper delineates this unique case of intracranial spread of femur chondrosarcoma.

Spinal Cord Stimulator Paddle Lead Surgery Complicated by Cerebrospinal Fluid Leak and Fistula Formation.

Spinal cord stimulation (SCS) paddle leads placed via laminectomy procedures have become common as more data accumulates with regards to their clinical efficacy. In this paper, we describe a case of a 72-year-old male patient with failed back surgery syndrome (FBSS) who underwent a thoracic laminectomy for permanent paddle lead placement. He went on to develop a complication that resulted in a large cerebrospinal fluid leak with a cerebrospinal fluid fistula formation.

The Impact of Intracranial Tumor Proximity to White Matter Tracts on Morbidity and Mortality: A Retrospective Diffusion Tensor Imaging Study.

Background: Using diffusion tensor imaging (DTI) in neurosurgical planning allows identification of white matter tracts and has been associated with a reduction in postoperative functional deficits. Objective: This study explores the relationship between the lesion-to-tract distance (LTD) and postoperative morbidity and mortality in patients with brain tumors in order to evaluate the role of DTI in predicting postoperative outcomes. Methods: Adult patients with brain tumors (n = 60) underwent preoperative DTI. Three major white matter pathways (superior longitudinal fasciculi [SLF], cingulum, and corticospinal tract) were identified using DTI images, and the shortest LTD was measured for each tract. Postoperative morbidity and mortality information was collected from electronic medical records. Results: The ipsilesional corticospinal tract LTD and left SLF LTD were significantly associated with the occurrence rate of total postoperative motor (P = .018) and language (P < .001) deficits, respectively. The left SLF LTD was also significantly associated with the occurrence rate of new postoperative language deficits (P = .003), and the LTD threshold that best predicted this occurrence was 1 cm (P < .001). Kaplan­Meier log-rank survival analyses in patients having high-grade tumors demonstrated a significantly higher mortality for patients with a left SLF LTD <1 cm (P = .01). Conclusion: Measuring tumor proximity to major white matter tracts using DTI can inform clinicians of the likelihood of postoperative functional deficits. A distance of 1 cm or less from eloquent white matter structures most significantly predicts the occurrence of new deficits with current surgical and imaging techniques.

Dynamic susceptibility contrast and dynamic contrast-enhanced MRI characteristics to distinguish microcystic meningiomas from traditional Grade I meningiomas and high-grade gliomas.

OBJECTIVE Microcystic meningioma (MM) is a meningioma variant with a multicystic appearance that may mimic intrinsic primary brain tumors and other nonmeningiomatous tumor types. Dynamic susceptibility contrast (DSC) and dynamic contrast-enhanced (DCE) MRI techniques provide imaging parameters that can differentiate these tumors according to hemodynamic and permeability characteristics with the potential to aid in preoperative identification of tumor type. METHODS The medical data of 18 patients with a histopathological diagnosis of MM were identified through a retrospective review of procedures performed between 2008 and 2012; DSC imaging data were available for 12 patients and DCE imaging data for 6. A subcohort of 12 patients with Grade I meningiomas (i.e., of meningoepithelial subtype) and 54 patients with Grade IV primary gliomas (i.e., astrocytomas) was also included, and all preoperative imaging sequences were analyzed. Clinical variables including patient sex, age, and surgical blood loss were also included in the analysis. Images were acquired at both 1.5 and 3.0 T. The DSC images were acquired at a temporal resolution of either 1500 msec (3.0 T) or 2000 msec (1.5 T). In all cases, parameters including normalized cerebral blood volume (CBV) and transfer coefficient (kTrans) were calculated with region-of-interest analysis of enhancing tumor volume. The normalized CBV and kTrans data from the patient groups were analyzed with 1-way ANOVA, and post hoc statistical comparisons among groups were conducted with the Bonferroni adjustment. RESULTS Preoperative DSC imaging indicated mean (± SD) normalized CBVs of 5.7 ± 2.2 ml for WHO Grade I meningiomas of the meningoepithelial subtype (n = 12), 4.8 ± 1.8 ml for Grade IV astrocytomas (n = 54), and 12.3 ± 3.8 ml for Grade I meningiomas of the MM subtype (n = 12). The normalized CBV measured within the enhancing portion of the tumor was significantly higher in the MM subtype than in typical meningiomas and Grade IV astrocytomas (p < 0.001 for both). Preoperative DCE imaging indicated mean kTrans values of 0.49 ± 0.20 min-1 in Grade I meningiomas of the meningoepithelial subtype (n = 12), 0.27 ± 0.12 min-1 for Grade IV astrocytomas (n = 54), and 1.35 ± 0.74 min-1 for Grade I meningiomas of the MM subtype (n = 6). The kTrans was significantly higher in the MM variants than in the corresponding nonmicrocystic Grade 1 meningiomas and Grade IV astrocytomas (p < 0.001 for both). Intraoperative blood loss tended to increase with increased normalized CBV (R = 0.45, p = 0.085). CONCLUSIONS An enhancing cystic lesion with a normalized CBV greater than 10.3 ml or a kTrans greater than 0.88 min-1 should prompt radiologists and surgeons to consider the diagnosis of MM rather than traditional Grade I meningioma or high-grade glioma in planning surgical care. Higher normalized CBVs tend to be associated with increased intraoperative blood loss.

A Unique Case of Intracranial Mucormycosis Following an Assault.

Intracranial mucormycosis is a very unusual presentation of an infection after a depressed skull fracture due to an assault. Only sporadic cases have been reported in the literature previously. A 30-year-old male with a traumatic brain injury following an assault, status-post debridement and elevation of a depressed skull fracture, was discharged home several weeks postoperatively. A CT scan of the head with contrast was obtained due to mental status changes and revealed an enhancing ring-shaped lesion in the right frontal lobe consistent with a brain abscess. The patient was taken to the operating room for image-guided excisional biopsy of the lesion, with pathology revealing mucormycosis.

Intravascular Ultrasound for Intracranial and Extracranial Carotid Artery Stent Placement.

Intravascular ultrasound (IVUS) can provide valuable information regarding endoluminal morphology. We present the first description of IVUS-guided intracranial and extracranial carotid artery stent placement for arterial dissection. A 41-year-old female with a sudden-onset headache and blurred vision underwent a computed tomography (CT) angiogram imaging that revealed bilateral carotid artery dissections (BCAD) and a left vertebral artery dissection (VAD). Endovascular treatment (EVT) of a long segment right carotid artery dissection (CAD) was performed employing two Carotid WALLSTENT™ Monorails™ (8 x 36 mm, 10 x 31 mm) (Boston Scientific, Marlborough, MA). With the help of the IVUS, the distal stent was placed up to the petrous carotid artery, followed by the placement of the second stent in the immediate proximal location with some overlap that extended down to the carotid artery bulb. Intraoperative angiography and post-stenting IVUS revealed excellent stent placement with good resolution of the dissection and good luminal patency with pseudolumen obliteration. Stent use for intracranial circulation dissections will continue to be a favorable option given the decreased morbidity of endovascular therapy in this location. As endovascular surgeons become more facile with the use of IVUS, using it as a guide for stent placement and post-stenting confirmation will help them to ensure proper positioning and improved patency rates.

Retraction: Cadaveric Study of Anatomic Far Distal Musculocutaneous and Median Nerve Communication.

[This retracts the article DOI: 10.7759/cureus.627.].

Cadaveric Study of Anatomic Far Distal Musculocutaneous and Median Nerve Communication.

One of the more commonly reported variations in musculocutaneous and median nerves is a communication between the two. Such communications have been noted in the literature for well over a century, and numerous studies have attempted to quantify their rate of incidence and classify their different patterns. Most communications occur close to the brachial plexus in the proximal arm; communications distal to the musculocutaneous nerve perforation of the coracobrachialis have been reported with less frequency, and several rare and unique communication patterns have been reported as case studies. This paper describes a case of a communicating branch between the musculocutaneous and median nerves, distal to the origin of the brachialis muscle. This communication was found during a routine educational dissection and is closer to the level of the elbow than previously documented communications that are distal to the musculocutaneous perforation of the coracobrachialis. Identification and documentation of the variety of musculocutaneous and median nerve communications is relevant to clinical diagnosis of peripheral nerve pathologies, as well as for planning surgical approaches and procedures.

Application of the Flexible CO2 Laser in Minimally Invasive Laminectomies: Technical Note.

Background Minimally invasive laminectomy is a very effective surgical method for treating lumbar stenosis. However, this technique can be technically difficult, especially in patients suffering from severe stenosis. The contralateral decompression from a unilateral approach can result in durotomy during removal of the hypertrophied ligamentum flavum. This complication can be difficult to treat through a small working channel. Objective To detail our group's operative experience with the CO2 laser and discuss our results and previous studies in the literature reporting results.  Methods The CO2 laser (Omniguide, Boston, MA) was investigated in the surgical ablation of the contralateral ligamentum flavum during minimally invasive laminectomies. Forty levels have been investigated thus far. The amount of voltage needed to adequately desiccate and remove the ligamentum flavum safely as well as the effectiveness of this technique were investigated. Results The contralateral ligamentum flavum could be removed effectively using the 9 to 11 watt continuous wavelength (10,600 nanometer) power setting on the CO2 laser. Shrinkage of the contralateral ligamentum flavum facilitated its removal using a number 2 Kerrison Punch. No durotomies occurred, and the use of the laser did not significantly lengthen operative times.  Conclusions The CO2 laser appears to be a useful tool in the armamentarium of instruments available to the minimally invasive spine surgeon and may help to reduce the incidence of durotomies when performing minimally invasive laminectomies.

Clinical Utility of Thallium-201 Single Photon Emission Computed Tomography and Cerebrospinal Fluid Epstein-Barr Virus Detection Using Polymerase Chain Reaction in the Diagnosis of AIDS-Related Primary Central Nervous System Lymphoma.

OBJECTIVE: To determine the diagnostic efficiency of thallium-201 single photon emission computed tomography (SPECT) and Epstein-Barr virus (EBV) polymerase chain reaction (PCR) in the differentiation of primary central nervous system lymphoma (PCNSL) from other central nervous system processes in patients with HIV/AIDS. DESIGN/METHODS: Over 10 years, 68 thallium-201 SPECT scans were performed on neurologically symptomatic HIV+ patients with focal lesions on CT or MRI at the Johns Hopkins Hospital. Diagnoses were then established by either autopsy, biopsy, or clinical response to anti-toxoplasmosis therapy. Patients were categorized prior to a prospective clinical reading of the SPECT scans by nuclear medicine physicians. RESULTS: In our patient sample overall, the diagnostic efficiency of thallium-201 SPECT was 79%. The diagnostic accuracy of EBV PCR testing alone in a subset of 22 patients in our study that had CSF analyzed was 73%. However, when both positive EBV PCR and positive thallium-201 SPECT results were used together, the diagnostic accuracy improved to 100% based on a sample of 13 patients where EBV PCR and SPECT imaging results were concordant.  CONCLUSION: Thallium-201 SPECT has a relatively high positive predictive value with regards to the diagnosis of PCNSL, which suggests that patients with positive results could undergo empiric radiation treatment without resorting to brain biopsy. However, the predictive value can be increased by testing for CSF EBV using PCR. Alternatively, if CSF cannot be safely obtained because of mass effect, we believe that these data still suggest that empiric radiation treatment should be considered when discussing treatment options with patients with a positive thallium-201 SPECT.