Endovascular revascularization of chronically occluded common carotid artery for symptomatic cerebral hypoperfusion.

Endovascular recanalization is increasingly being utilized in symptomatic patients with chronically occluded carotid arteries.1 In carefully selected patients, endovascular recanalization has shown to lower the risk of ischemic events when compared to medical management alone.1 However, successful endovascular revascularization is technically challenging and not without risk.1, 2 In this video, we demonstrate a case of a 64-year-old woman who presented with recurrent transient ischemic attacks. On imaging she was found to have a chronic total occlusion of the common carotid artery from the arch. After obtaining informed consent, the patient underwent a successful endovascular recanalization and stenting of a chronically occluded left common carotid artery with aid from an intravascular guided re-entry catheter. Post operatively the patient developed a neck hematoma which improved and she returned to her neurological baseline. She reported no further symptoms on her three month follow up.

Vagus nerve stimulation using an endovascular electrode array.

Objective. Vagus nerve stimulation (VNS), which involves a surgical procedure to place electrodes directly on the vagus nerve (VN), is approved clinically for the treatment of epilepsy, depression, and to facilitate rehabilitation in stroke. VNS at surgically implanted electrodes is often limited by activation of motor nerve fibers near and within the VN that cause neck muscle contraction. In this study we investigated endovascular VNS that may allow activation of the VN at locations where the motor nerve fibers are not localized.Approach. We used endovascular electrodes within the nearby internal jugular vein (IJV) to electrically stimulate the VN while recording VN compound action potentials (CAPs) and neck muscle motor evoked potentials (MEPs) in an acute intraoperative swine experiment.Main Results. We show that the stimulation electrode position within the IJV is critical for efficient activation of the VN. We also demonstrate use of fluoroscopy (cone beam CT mode) and ultrasound to determine the position of the endovascular stimulation electrode with respect to the VN and IJV. At the most effective endovascular stimulation locations tested, thresholds for VN activation were several times higher than direct stimulation of the nerve using a cuff electrode; however, this work demonstrates the feasibility of VNS with endovascular electrodes and provides tools to optimize endovascular electrode positions for VNS.Significance. This work lays the foundation to develop endovascular VNS strategies to stimulate at VN locations that would be otherwise too invasive and at VN locations where structures such as motor nerve fibers do not exist.

Revascularization of a Complex Case of Vertebrobasilar Insufficiency with Occipital Artery-Anterior Inferior Cerebellar Artery Bypass.

Atherosclerotic disease is the most common etiology in causing posterior circulation strokes and can be found within the intracranial vertebrobasilar system.1 Endovascular and surgical approaches to treat this disease have been defined with both advantages and disadvantages.2,3 We present a case of surgical revascularization of a complex case of vertebrobasilar insufficiency with occipital artery (OA)-anterior inferior cerebellar artery (AICA) bypass (Video 1). A 56-year-old gentleman presented with severe, disabling, and progressive symptoms of vertebrobasilar insufficiency refractory to maximal medical management. Symptom onset was 2 years prior after suffering a left lateral medullary stroke due to a left vertebral artery (VA) occlusion. Angiography showed left VA occlusion after the origin of the posterior inferior cerebellar artery (PICA) and a hypoplastic right VA mostly ending in a PICA with a small and critically stenosed branch to the basilar artery. An initial attempt to revascularize the chronic totally occluded left VA using a combination of anterograde and retrograde (via PComm) approaches was unsuccessful. The decision was made to proceed with an OA-AICA bypass. The end-to-side anastomosis was conducted in the right cerebellopontine cistern and was uncomplicated. Postoperative angiography demonstrated a patent bypass with brisk OA-to-AICA flow with retrograde filling of the basilar artery and its branches. No perioperative strokes. The patient remained free of recurrent symptoms of vertebrobasilar insufficiency at 6 months' follow-up.

Human "live cadaver" neurovascular model for proximal and distal mechanical thrombectomy in stroke.

BACKGROUND: Preclinical testing platforms that accurately replicate complex human cerebral vasculature are critical to advance neurointerventional knowledge, tools, and techniques. Here, we introduced and validated a human "live cadaveric" head-and-neck neurovascular model optimized for proximal and distal vascular occlusion and recanalization techniques. METHODS: Human cadaveric head-and-neck specimens were cannulated bilaterally in the jugular veins, carotid, and vertebral arteries. Specimens were then coupled with modular glass models of the aorta and extracranial carotid arteries, as well as radial and femoral access ports. Intracranial physiological flow was simulated using a flow-delivery system and blood-mimicking fluid. Baseline anatomy, histological, and mechanical properties of cerebral arteries were compared with those of fresh specimens. Radiopaque clot analogs were embolized to replicate proximal and distal arterial occlusions, followed by thrombectomy. Experienced interventionalists scored the model on different aspects. RESULTS: Compared with counterpart fresh human arteries, formalin-fixed arteries showed similar mechanical properties, including maximum stretch, increased tensile strength/stiffness, and friction coefficients were also not significantly different. On histology, minimal endothelial damage was noted in arteries after 3 months of light fixation, otherwise the arterial wall maintained the structural integrity. Contrast angiographies showed no micro- or macro-vasculature obstruction. Proximal and distal occlusions created within the middle cerebral arteries were consistently obtained and successfully recanalized. Additionally, interventionists scored the model highly realistic, indicating great similarity to patients' vasculature. CONCLUSIONS: The human "live cadaveric" neurovascular model accurately replicates the anatomy, mechanics, and hemodynamics of cerebral vasculature and allows the performance of neurointerventional procedures equivalent to those done in patients.

Evaluation of an in vivo preclinical model for human middle meningeal artery embolization using the posterior intercostal artery of the swine.

BACKGROUND: Embolization of the middle meningeal artery (MMA) is a promising minimally invasive technique that is gaining traction in the treatment of chronic subdural hematoma. Unfortunately, the human meninges and associated arteries are significantly larger than those of conventional laboratory animals, making the development of a clinically relevant animal model for testing of embolization agents elusive. OBJECTIVE: To introduce the posterior intercostal artery (PIA) model in swine and provide anatomical, angiographic, histological, and procedural data to validate its relevance in modeling the human MMA. METHODS: In human cadaveric specimens, 3D angiograms of the internal maxillary arteries (n=6) were obtained and the dura with MMA were harvested and histologically processed. Angiographic and histologic data of the human MMA were compared with the swine PIA (three animals). Then, embolization of the PIA (n=48 arteries) was conducted with liquid embolization agent (Onyx, Medtronic), and angiographic and histological results were assessed acutely (four animals) and after 30 days (two animals). RESULTS: The human MMA has equivalent diameter, length, branching pattern, 3D trajectory, and wall structure to those of swine PIAs. Each swine has 12 to 14 PIAs (6-7 per side) suitable for acute or chronic embolization, which can be performed with high fidelity using the same devices, agents, and techniques currently used to embolize the MMA. The arterial wall structure and the acute and chronic histological findings in PIAs after embolization are comparable to those of humans. CONCLUSIONS: This PIA model in swine could be used for research and development; objective benchmarking of agents, devices, and techniques; and in the training of neurointerventionalists.

Construction and Validation of a Benchtop Model for Testing of Mechanical Thrombectomy Devices for Pulmonary Embolism.

PURPOSE: This study aims to define the process of designing and manufacturing 3D printed and glass models of the pulmonary artery (PA) and utilizing them in a test bed for evaluation of devices for mechanical thrombectomy of pulmonary embolism (PE). MATERIALS AND METHODS: Patient derived computed tomography angiography (CTA) images of the PA were digitally converted into a hollowed-out structure and translated into clear 3D printed and glass models. A test bed was created using a peristaltic pump and silicone tubing connected to the models. Human clot analogs were then prepared and injected within the models. Thrombectomy testing was done using clinically used predicates and baseline characteristics of the models were evaluated by independent interventionalists. RESULTS: The mean sizes of the main pulmonary artery (MPA) for the 3D printed model and glass model were 30.4 mm and 29.2 mm, mimicking those of the patient's PA obtained on CTA. Heterogeneous human clot analogs were created with fibrin composition ranging from 60 to 30%. Mechanical thrombectomy was successfully attempted by independent interventionalists. Both the 3D printed, and glass model were appraised as very good for multiple attributes. CONCLUSION: A complete test bed using 3D printed and glass models of the PA with human clot analogs was created for testing of mechanical thrombectomy devices for PE.

Surgical Techniques and Nuances for Superior Cervical Ganglionectomy and Decentralization in Rats.

The sympathetic nervous system has been implicated in various physiological and pathological processes, including regulation of homeostatic functions, maintenance of the circadian rhythms, and neuronal disruption and recovery after injury. Of special interest is focus on the role of the superior cervical ganglion (SCG) in regulating the daily changes in pineal function. Removal of the superior cervical ganglion (SCGx) and decentralization have served as valuable microsurgical models to investigate the effects of surgical denervation on this gland or organ. In this chapter, we offer information about methodologies for performing SCGx along with decentralization and denervation procedures, including details about recommended equipment as well as tips that can improve these techniques.

An Audit of the effect of Bone Morphogenetic Protein-2 Treatment in patients with non-union of long bone fractures.

OBJECTIVE: To evaluate the outcomes, clinical and radiological application of Bone Morphogenetic Protein-2 alone versus Bone Morphogenetic Protein-2 with autograft in long bone non-unions. METHODS: A prospective review of patients was done with fracture non-union admitted to Aga Khan University Hospital, Karachi, from January 2016 to January 2019. The patients were divided into two groups; those exposed to Bone Morphogenetic Protein-2 alone in group 1, and those exposed to Bone Morphogenetic Protein-2 plus autologous graft in group 2. RESULTS: Background characteristics of both the groups were analysed. Patients were followed up at 6, 12 and 24 weeks through their medical records. The primary outcome was postoperative union at 6, 12 and 24. Union was defined by having the clinical union as well as the radiological union at the same time of assessment. Of the 80 patients enrolled, 13(16.25%) were excluded, and 5(6.25%) were lost to follow-up. The final sample had 62(77.5%) patients; 35(56.5%) in group 1, and 27(43.5%) in group 2. Union at 6 weeks was observed in 13(21%) patients; 8(62%) in group 1, and 5(38%) in group 2. Union at 12 weeks was observed in 38(61%) patients; 20(53%) in group 1, and 18(47%) in group 2. CONCLUSIONS: Results showed that using the adjuvant treatment alone was not worse than using it along with bone autologous graft.

Electroencephalogram and heart rate variability features as predictors of responsiveness to vagus nerve stimulation in patients with epilepsy: a systematic review.

INTRODUCTION: Vagus nerve stimulation (VNS) is a mainstay treatment in people with medically refractive epilepsy with a growing interest to identify biomarkers that are predictive of VNS efficacy. In this review, we looked at electroencephalography (EEG) and heart rate variability (HRV) parameters as potential biomarkers. METHODOLOGY: A comprehensive search of several databases limited to the English language and excluding animal studies was conducted. Data was collected from studies that specifically reviewed preoperative EEG and HRV characteristics as predictive factors of VNS outcomes. RESULTS: Ten out of 1078 collected studies were included in this review, of which EEG characteristics were reported in seven studies; HRV parameters were reported in two studies, and one study reported both. For EEG, studies reported a lower global rate of synchronization in alpha, delta, and gamma waves as predictors of the VNS response. The P300 wave, an evoked response on EEG, had conflicting results. Two studies reported high P300 wave amplitudes in nonresponders and low amplitudes in responders, whereas another study reported high P300 wave amplitudes in responders. For HRV, one study reported high-frequency power as the only parameter to be significantly lower in responders. In contrast, two studies from the same authors showed that HRV parameters were not different between responders and nonresponders. CONCLUSION: HRV parameters and EEG characteristics including focal seizures and P300 wave have been reported as potential biomarkers for VNS outcomes in people with medically refractive epilepsy. However, the contradictory findings imply a need for validation through clinical trials.

Thirty-Day Stroke and Mortality After Carotid Revascularization Among Octogenarians with Symptomatic Carotid Stenosis: Real-World Evidence from a National Surgical Quality Registry.

BACKGROUND: The outcomes of carotid revascularization among octogenarians are not well studied. We present analyses of 30-day stroke and mortality of patients aged ≥80 years using real-world data from a national surgical quality registry. METHODS: The National Surgical Quality Improvement Program targeted data set for carotid endarterectomy (CEA) and carotid angioplasty and stenting (CAS) was queried for patients aged ≥80 years undergoing CEA and CAS between 2012 and 2019. RESULTS: A total of 122 and 3013 patients aged ≥80 years with symptomatic carotid stenosis undergoing CAS and CEA, respectively, were identified. Patients with CAS were more likely to be older than 90 years (P = 0.006) and have diabetes (P = 0.036), were more likely to have high-risk anatomy (P < 0.001), but had lower American Society of Anesthesiologists score (P < 0.001). An ipsilateral stroke had been experienced by 43.6% of patients with CAS and 44.7% of patients with CEA. The rate of 30-day composite outcome was 6.4% in the CAS group and 4.5% in the CEA group (P = 0.326). The f 30-day mortality was significantly higher for CAS (5.6% vs. 1.7%, P = 0.001); however, the difference between the cohorts was not significant (CAS, 2.4% vs. CEA, 3.4%, P = 0.555). On multivariable analysis, CEA was associated with significantly lower odds of mortality (odds ratio [OR], 0.32; P = 0.0145). Symptom presentation other than ipsilateral stroke was associated with significantly decreased odds of 30-day outcome (amaurosis fugax/transient monocular blindness, OR, 0.39, P = 0.004; transient ischemic attack, OR, 0.57, P = 0.003), whereas higher age had significantly increased odds (OR, 1.95; P = 0.0172). CONCLUSIONS: Real-world analyses from a surgical quality registry show that CEA may be associated with lower odds of mortality compared with CAS among octogenarians.

EMR adoption in Dhaka, Bangladesh: a template to index pediatric central nervous system tumor care and a review of preliminary neuro-oncologic observations.

PURPOSE: To describe the design, implementation, and adoption of a simplified electronic medical record (EMR) and its use in documenting pediatric central nervous system (CNS) tumors at a tertiary care referral hospital in South-East Asia. METHODS: A novel EMR, cataloguing pediatric CNS tumors was used to collect data from August 2017 to March 2020 at National Institute of Neurosciences and Hospital (NINS&H) in Dhaka, Bangladesh. RESULTS: Two hundred forty-nine pediatric patients with a CNS tumor were admitted to NINS&H. Fifty-eight percent of patients were male, and the median age was 8 years. A total of 188/249 patients (76%) underwent surgery during their index admission. Radiographic locations were known for 212/249 (85%) of cases; the most common radiographic locations were infratentorial (81/212; 38%), suprasellar (45/212; 21%), and supratentorial (29/212; 14%). A histopathological classification was reported on 156/249 (63%) of patients' cytology. The most common infratentorial pathologies were medulloblastoma (22/47; 47%) and pilocytic astrocytoma (14/47; 30%). The median time between admission and surgery was 36 days, while the median post-operation stay was 19.5 days. CONCLUSIONS: The feasibility of a basic EMR platform for a busy pediatric neurosurgery department in a lower-middle income country is demonstrated, and preliminary clinical data is reviewed. A wide variety of pediatric CNS tumors were observed, spanning the spectrum of anatomic locations and histopathologic subtypes. Surgical intervention was performed for the majority of patients. Barriers to care include limited molecular diagnostics and unavailable data on adjuvant therapy. Future targets include improvement of clinical documentation in the pre-operative and post-operative period.

Extra-Intimal Carotid Endarterectomy: Two-Dimensional Microsurgical Approach.

Carotid endarterectomy is a standard treatment for patients with symptomatic carotid artery stenosis.1 Surgical techniques require a full-thickness incision (longitudinal, diagonal, or transverse) through the carotid wall. This incision results in significant plaque disruption and precludes harvesting of intact specimens for research. The video demonstrates an endarterectomy technique for removal of intact plaques using an extra-intimal approach. A 70-year-old man presented to our service with a history of aphasia. Neuroimaging showed the presence of an 80%-90% calcified stenosis of the left internal carotid artery. Brain magnetic resonance imaging revealed multiple acute and subacute left hemispheric strokes. The decision was made to proceed with extra-intimal carotid endarterectomy of the left internal carotid artery after obtaining informed consent. To this end, after appropriate exposure of the carotid artery bifurcation, the adventitia and the tunica media were transected longitudinally followed by the creation of a circumferential dissection plane between the tunica media and the intima (i.e., extra-intimal). After sharply transecting the intimal inlets and outlet of the atheroma, the arteriotomy was repaired in usual fashion (Video 1). The patient was discharged home the next day without complications and remained asymptomatic at 1-year follow-up. To date, this technique has been successfully used in 55 consecutive patients with no intraoperative or postoperative complications. This technique is fast, reproducible, and effective even in highly calcified lesions that are otherwise hard to cut. The approach requires minimal arterial wall and atheroma manipulation and procures intact specimens for high-quality research.

Per-pass analysis of recanalization and good neurological outcome in thrombectomy for stroke: Systematic review and meta-analysis.

BACKGROUND AND AIM: First pass effect (FPE) is defined as achieving a complete recanalization with a single thrombectomy device pass. Although clinically desired, FPE is reached in less than 30% of thrombectomy procedures. Multiple device passes are often necessary to achieve successful or complete recanalization. We performed a systematic review and meta-analysis to determine the recanalization rate after each pass of mechanical thrombectomy and its association with good neurological outcome. METHODS: A literature search was performed for studies reporting the number of device passes required for either successful (mTICI 2b or higher) or complete (mTICI 2c or higher) recanalization. Using random-effect meta-analysis, we evaluated the likelihood of recanalization and good neurological outcome (measured with the modified Rankin Score <2 at 90 days) after each device pass. RESULTS: Thirteen studies comprising 4197 patients were included. Among cases with failed first pass, 24% of them achieved final complete recanalization and 45% of them achieved final successful recanalization. Independently to the total number of previously failed attempts, the likelihood of achieving successful recanalization was 30% per pass, and the likelihood to achieve complete recanalization was about 20% per pass. The likelihood of good neurological outcome in patients with final successful recanalization decreased after each device pass: 55% after the first pass, 48% after the second pass, 42% after the third pass, 36% after the fourth pass, and 26% for 5 passes or more. CONCLUSION: Each pass is associated with a stable likelihood of recanalization but a decreased likelihood of good neurological outcome.

Correlation of Neutrophil to Lymphocyte Ratio with Expression of Neutrophil Extracellular Traps Within Stroke Emboli.

BACKGROUND & PURPOSE: It has been hypothesized that circulating neutrophils have a direct correlation with the composition of emboli in acute ischemic stroke (AIS). The aim of this study is to evaluate the association between neutrophil-lymphocyte ratio (NLR) in peripheral blood and the expression of neutrophil extracellular traps (NETs) within stroke emboli. METHODS: Consecutive patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) that underwent mechanical thrombectomy (MT) were included. Patients were divided into two groups based on NLR median value. Retrieved thrombi were histologically analyzed using Martius Scarlett Blue (MSB) for main thrombus components including red blood cells (RBCs), white blood cells (WBCs), fibrin and platelet. Immunohistochemistry staining for von Willebrand Factor (vWF) and anti-citrullinated H3 (H3Cit; NETs marker) was also performed. RESULTS: Samples from a total of 84 patients were included. The average percentage of RBCs, WBCs, fibrin, platelet, H3Cit, and vWF components in thrombi were 45.1%, 3.5%, 21.8%, 29.6%, 19.7% and 14.8% respectively. When stratifying by NLR group [low (≤3.94) versus high (>3.95)], high NLR group had significantly more WBCs (4.5%), fibrin (24.2%), H3Cit (22.7%) and vWF (17.1%) thrombus fractions compared to low NLR group. Additionally, RBC content (38.8%) was lower in the high NLR group. CONCLUSIONS: NLR is correlated with the amounts of WBCs, fibrin, NETs and vWF within the thrombi retrieved from AIS patients due to LVO.

Quantification of clot spatial heterogeneity and its impact on thrombectomy.

BACKGROUND: Compositional and structural features of retrieved clots by thrombectomy can provide insight into improving the endovascular treatment of ischemic stroke. Currently, histological analysis is limited to quantification of compositions and qualitative description of the clot structure. We hypothesized that heterogeneous clots would be prone to poorer recanalization rates and performed a quantitative analysis to test this hypothesis. METHODS: We collected and did histology on clots retrieved by mechanical thrombectomy from 157 stroke cases (107 achieved first-pass effect (FPE) and 50 did not). Using an in-house algorithm, the scanned images were divided into grids (with sizes of 0.2, 0.3, 0.4, 0.5, and 0.6 mm) and the extent of non-uniformity of RBC distribution was computed using the proposed spatial heterogeneity index (SHI). Finally, we validated the clinical significance of clot heterogeneity using the Mann-Whitney test and an artificial neural network (ANN) model. RESULTS: For cases with FPE, SHI values were smaller (0.033 vs 0.039 for grid size of 0.4 mm, P=0.028) compared with those without. In comparison, the clot composition was not statistically different between those two groups. From the ANN model, clot heterogeneity was the most important factor, followed by fibrin content, thrombectomy techniques, red blood cell content, clot area, platelet content, etiology, and admission of intravenous tissue plasminogen activator (IV-tPA). No statistical difference of clot heterogeneity was found for different etiologies, thrombectomy techniques, and IV-tPA administration. CONCLUSIONS: Clot heterogeneity can affect the clot response to thrombectomy devices and is associated with lower FPE. SHI can be a useful metric to quantify clot heterogeneity.

Current Landscape and Future Prospects of Radiation Sensitizers for Malignant Brain Tumors: A Systematic Review.

BACKGROUND: Radiation therapy (RT) is the cornerstone of management of malignant brain tumors, but its efficacy is limited in hypoxic tumors. Although numerous radiosensitizer compounds have been developed to enhance the effect of RT, progress has been stagnant. Through this systematic review, we provide an overview of radiosensitizers developed for malignant brain tumors, summarize their safety and efficacy, and evaluate areas for possible improvement. METHODS: Following PRISMA guidelines, PubMed, EMBASE, Cochrane, and Web of Science were searched using terminology pertaining to radiosensitizers for brain tumor RT. Articles reporting clinical evidence of nonantineoplastic radiosensitizers with RT for malignant central nervous system tumors were included. Data of interest were presumed mechanism of action, median overall survival (OS), progression-free survival (PFS), and adverse events. RESULTS: Twenty-two unique radiosensitizers were identified. Only 2/22 agents (fluosol with oxygen, and efaproxiral) showed improvement in OS in patients with glioblastoma and brain metastasis, respectively. A larger study was not able to confirm the latter. Improved PFS was reported with use of metronidazole, sodium glycididazole, and chloroquine. There was a wide range of toxicities, which prompted change of schedule or complete discontinuation of 9 agents. CONCLUSIONS: Progress in radiosensitizers for malignant CNS tumors has been limited. Only 2 radiosensitizers have shown limited improvement in survival. Alternative strategies such as synthetic drug design, based on a mechanism of action that is independent of crossing the blood-brain barrier, may be necessary. Use of drug development strategies using new technologies to overcome past challenges is necessary.

Mutational landscape of head and neck squamous cell carcinomas in a South Asian population.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer type globally and contributes significantly to burden of disease in South Asia. In Pakistan, HNSCC is among the most commonly diagnosed cancer in males and females. The increasing regional burden of HNSCC along with a unique set of risk factors merited a deeper investigation of the disease at the genomic level. Whole exome sequencing of HNSCC samples and matched normal genomic DNA analysis (n=7) was performed. Significant somatic single nucleotide variants (SNVs) were identified and pathway analysis performed to determine frequently affected signaling pathways. We identified significant, novel recurrent mutations in ASNS (asparagine synthetase) that may affect substrate binding, and variants in driver genes including TP53, PIK3CA, FGFR2, ARID2, MLL3, MYC and ALK. Using the IntOGen platform, we identified MAP kinase, cell cycle, actin cytoskeleton regulation, PI3K-Akt signaling and other pathways in cancer as affected in the samples. This data is the first of its kind from the Pakistani population. The results of this study can guide a better mechanistic understanding of HNSCC in the population, ultimately contributing new, rational therapeutic targets for the treatment of the disease.

Three-dimensional Visualization Software Assists Learning in Students with Diverse Spatial Intelligence in Medical Education.

This study evaluated effect of mental rotation (MR) training on learning outcomes and explored effectiveness of teaching via three-dimensional (3D) software among medical students with diverse spatial intelligence. Data from n = 67 student volunteers were included. A preliminary test was conducted to obtain baseline level of MR competency and was utilized to assign participants to two experimental conditions, i.e., trained group (n = 25) and untrained group (n = 42). Data on the effectiveness of training were collected to measure participants' speed and accuracy in performing various MR activities. Six weeks later, a large class format (LCF) session was conducted for all students using 3D software. The usefulness of technology-assisted learning at the LCF was evaluated via a pre- and post-test. Students' feedback regarding MR training and use of 3D software was acquired through questionnaires. MR scores of the trainees improved from 25.9±4.6 points to 28.1±4.4 (P = 0.011) while time taken to complete the tasks reduced from 20.9±3.9 to 12.2±4.4 minutes. Males scored higher than females in all components (P = 0.016). Further, higher pre- and post-test scores were observed in trained (9.0±1.9 and 12.3±1.6) versus untrained group (7.8±1.8; 10.8±1.8). Although mixed-design analysis of variance suggested significant difference in their test scores (P < 0.001), both groups reported similar trend in improvement by means of 3D software (P = 0.54). Ninety-seven percent of students reported technology-assisted learning as an effective means of instruction and found use of 3D software superior to plastic models. Software based on 3D technologies could be adopted as an effective teaching pedagogy to support learning across students with diverse levels of mental rotation abilities.

Development of Criteria Highly Suggestive of Spinal Tuberculosis.

BACKGROUND: In a developing country there is a need for development of criteria that can be used for the diagnosis of spinal tuberculosis, which is common in that region. METHODS: Demographic, clinical, and radiologic features of spinal tuberculosis and spinal epidural tumors have been compared statistically, and inferences have been drawn in terms of P values, sensitivity, specificity, positive predictive values, and negative predictive values. RESULTS: A statistically significant relationship was found between spinal tuberculosis and spinal pain, fever, gradually progressive lower limb weakness, contrast-enhancing epidural ± paravertebral lesions, continuous levels affected, spinal deformity, and raised erythrocyte sedimentation rate. CONCLUSIONS: These relationships were considered the most probable criteria for the diagnosis of spinal tuberculosis.