Endoscopic endonasal transsphenoidal Onyx embolization of a paracavernous dural arteriovenous fistula.

Paracavernous dural arteriovenous fistulas (pdAVFs) are extremely rare and can mimic carotid cavernous fistulas (CCFs) in both clinical presentation and imaging characteristics. Access to the venous pouch often presents the greatest challenge in the treatment of pdAVFs. Here we present a novel access technique utilizing an endoscopic endonasal transsphenoidal approach, where we directly puncture the venous pouch under both stereotactic guidance and endoscopic visualization, thereby completely embolizing a pdAVF with no alternate access (video 1). neurintsurg;15/10/1055/V1F1V1Video 1Technical video demonstrates the complete embolization of a pdAVF using an endoscopic endonasal transsphenoidal approach.

Late Testicular Yolk Sac Tumor With Cerebellar Metastasis and a Rapid Recurrence After a Gross Total Resection: A Case Report.

Yolk sac tumor (YST) is the most common prepubertal testicular tumor. It is considered a subtype of non-seminoma germ cell tumor (NSGCT) that is presumed to have an aggressive behavior with high malignant potential, thus requiring multimodality treatment with resection and chemotherapy. Treatment is curative for the majority of patients, even the ones with relapse after a few years. Here, we describe for the first time an atypical case of YST recurrence 17 years after primary treatment of YST. This is a case of YST in a 32-year-old man who presented with a large cerebellar mass consistent with YST recurrence after being in remission for 17 years. He underwent suboccipital craniotomy and complete excision of the tumor, as evident on postoperative MRI with a plan for stereotactic radiosurgery with dose and fractionation determined by MRI at four weeks postoperatively. However, the four-week MRI postoperatively revealed a large mass that was engulfing the prior resection cavity, indicative of unusual rapid tumor recurrence despite evidence of complete resection. The highly aggressive nature of this tumor should prompt clinicians to consider chemotherapy and radiation earlier than four weeks postoperatively.

Metastatic Renal Cell Carcinoma to the Cerebrum in a Patient With Lynch Syndrome: A Case Report.

Hereditary nonpolyposis colorectal cancer (HNPCC) or Lynch syndrome is an autosomal-dominant genetic disorder of DNA mismatch repair associated with many forms of cancer, especially colorectal and including renal cell. In this report, we present a case of a patient with a known history of HNPCC whose first presentation of renal cell carcinoma (RCC) was associated with a symptomatic intracranial lesion. After intracranial imaging, resection, and pathologic examination, the lesion was revealed to be of RCC origin. Further imaging revealed primary RCC. HNPCC may present with neurologic symptoms prior to the diagnosis of primary cancer, and lower levels of suspicion for intracranial lesions may be required to properly treat this patient population.

Effect of an additional neurosurgical resident on procedure length, operating room time, estimated blood loss, and post-operative length-of-stay.

Introduction: Neurosurgical residency training is costly, with expenses largely borne by the academic institutions that train residents. One expense is increased operative duration, which leads to poorer patient outcomes. Although other studies have assessed the effect of one resident assisting, none have investigated two residents; thus, we sought to investigate if two residents versus one scrubbed-in impacted operative time, estimated blood loss (EBL), and length-of-stay (LOS).Methods: In this retrospective review of patients who underwent a neurosurgical procedure involving one or two residents between January 2013 and April 2016, we performed multivariable linear regression to determine if there was an association between resident participation and case length, operating room time, EBL, and LOS. We also included patient demographics, attending surgeon, day of the week, start time, pre-operative LOS, procedure performed, and other variables in our model. Only procedures performed at least 40 times during the study period were analyzed.Results: Of 860 procedures that met study criteria, 492 operations were one of six procedures performed at least 40 times, which were anterior cervical discectomy and fusion, cerebrospinal fluid (CSF) shunt insertion, CSF shunt revision, lumbar laminectomy, intracranial hematoma evacuation, and non-skull base, supratentorial parenchymal brain tumor resection. An additional resident was associated with a 35.1-min decrease (p = .01) in operative duration for lumbar laminectomies. However, for intracranial hematoma evacuations, an extra resident was associated with a 24.1 min increase (p = .03) in procedural length. There were no significant differences observed in the other four surgeries.Conclusion: An additional resident may lengthen duration of intracranial hematoma evacuations. However, two residents scrubbed-in were associated with decreased lumbar laminectomy duration. Overall, an extra resident does not increase procedural duration, total operating room utilization, EBL, or post-operative LOS. Allowing two residents to scrub in may be a safe and cost-effective method of educating neurosurgical residents.

Cefazolin versus vancomycin for neurosurgical operative prophylaxis - A single institution retrospective cohort study.

OBJECTIVES: Cefazolin and vancomycin are common choices for neurosurgical antimicrobial prophylaxis. Cefazolin is typically first-line due to its lower toxicity profile and specificity for gram-positives such as skin commensals, while vancomycin is often reserved for patients with cephalosporin or penicillin allergies. However, one randomized clinical trial demonstrated superiority of vancomycin for cerebrospinal fluid (CSF) shunt insertions at a hospital with a high prevalence of methicillin-resistance Staphylococcus aureus (MRSA). We aimed to evaluate the association of prophylaxis choice and incidence of surgical site infection (SSI) at our own institution. PATIENTS AND METHODS: This was a retrospective cohort study of patients who underwent a neurosurgical operation from January 2013 to April 2016 at one particular hospital belonging to our institution. We included patients who received either only cefazolin or only vancomycin as their pre-incisional prophylaxis. Vancomycin was substituted for cefazolin in patients with known penicillin or cephalosporin allergy. Procedures requiring multiple attending surgeons were excluded. We defined a SSI as a confirmed culture isolated from the wound, implant (if pertinent), or CSF (if pertinent) within a year of surgery. Multivariable logistic regression was performed with consideration of antibiotic, operation performed, wound class, and procedure length. RESULTS: A total of 859 operations met study criteria; 664 patients received Cefazolin, and 195 received Vancomycin. We identified 22 SSIs, with 14 in the cefazolin (2.2%) and 8 in the vancomycin (4.1%) group. Upon logistic regression, there was no significant association of vancomycin substitution with incidence of SSIs between the two groups (odds ratio, 1.59; 95% CI, 0.42-6.00, p = .49). In the cefazolin group, 8/14 cultures were positive for S. aureus compared to 1/8 of the vancomycin group. CONCLUSIONS: There was no significant difference in neurosurgical site infection incidence when vancomycin prophylaxis was substituted for cefazolin. S. aureus was isolated from patients who received cefazolin at a higher rate although this was not statistically significant. At our institution, S. aureus makes up 36% of isolated organisms from inpatient and intensive care units. Institutions should consider their own investigations into local antibiograms, SSI rates, and choice of prophylaxis.

Derivation of a Predictive Score for Hemorrhagic Progression of Cerebral Contusions in Moderate and Severe Traumatic Brain Injury.

BACKGROUNDS: After traumatic brain injury (TBI), hemorrhagic progression of contusions (HPCs) occurs frequently. However, there is no established predictive score to identify high-risk patients for HPC. METHODS: Consecutive patients who were hospitalized (2008-2013) with non-penetrating moderate or severe TBI were studied. The primary outcome was HPC, defined by both a relative increase in contusion volume by ≥30 % and an absolute increase by ≥10 mL on serial imaging. Logistic regression models were created to identify independent risk factors for HPC. The HPC Score was then derived based on the final model. RESULTS: Among a total of 286 eligible patients, 61 (21 %) patients developed HPC. On univariate analyses, HPC was associated with older age, higher initial blood pressure, antiplatelet medications, anticoagulants, subarachnoid hemorrhage (SAH) subdural hematoma (SDH), skull fracture, frontal contusion, larger contusion volume, and shorter interval from injury to initial CT. In the final model, SAH (OR 6.33, 95 % CI, 1.80-22.23), SDH (OR 3.46, 95 % CI, 1.39-8.63), and skull fracture (OR 2.67, 95 % CI, 1.28-5.58) were associated with HPC. Based on these factors, the HPC Score was derived (SAH = 2 points, SDH = 1 point, and skull fracture = 1 point). This score had an area under the receiver operating curve of 0.77. Patients with a score of 0-2 had a 4.0 % incidence of HPC, while patients with a score of 3-4 had a 34.6 % incidence of HPC. CONCLUSIONS: A simple HPC Score was developed for early risk stratification of HPC in patients with moderate or severe TBI.

Miller Fisher Syndrome: A Case Report Highlighting Heterogeneity of Clinical Features and Focused Differential Diagnosis.

Miller Fisher Syndrome (MFS) is a rare variant of Guillain-Barré Syndrome (GBS) that has a geographically variable incidence. It is largely a clinical diagnosis based on the cardinal clinical features of ataxia, areflexia, and opthalmoplegia, however, other neurological signs and symptoms may also be present. Serological confirmation with the anti-GQ1b antibody is available and allows for greater diagnostic certainty in the face of confounding symptoms. A self-limiting course is typical of MFS. The following case report is that of a patient who presented with generalized weakness, somatic pain, inability to walk, and diplopia following an upper respiratory illness. The patient exhibited the classic triad of ataxia, areflexia, and opthalmoplegia characteristic of MFS, but also had less typical signs and symptoms making for a more challenging diagnostic workup. Our suspected diagnosis of MFS was serologically confirmed with positive anti-GQ1b antibody titer and the patient was successfully treated with Intravenous immune globulin (IVIG).

Comparing Radiation Dose from Conventional Fluoroscopy to Intraoperative Cone Beam CT (O-arm) during Percutaneous Lesioning Procedures of the Gasserian Ganglion.

INTRODUCTION: The use of intraoperative CT-guidance during the percutaneous treatment of trigeminal neuralgia has become increasingly popular due to the greater ease of foramen ovale cannulation and decreased procedure times. Concerns regarding radiation dose to the patient, however, remain unaddressed. We sought to compare the emitted radiation dose from fluoroscopy with intraoperative CT for these procedures. METHODS: A retrospective review of percutaneous lesioning procedures for trigeminal neuralgia performed between 2010 until 2012 at our institution was conducted and radiation doses to the patient were recorded. We subsequently simulated four separate percutaneous trigeminal rhizotomies using the O-arm intraoperative CT (Medtronics, Minneapolis, MN, USA) to cannulate the foramen ovale bilaterally in two formalin-fixed cadaver heads. RESULTS: Seventeen successful percutaneous treatments for trigeminal neuralgia were performed during the study period. Eleven procedures containing complete records were included in the final analysis. For procedures using fluoroscopy, the mean dosage was 15.2 mGys (range: 1.15 - 47.95, 95% CI 7.34 - 22.99). Radiation dosage from the O-arm imaging system was 16.55 mGy for all four cases. An unequal variance t-test did not reach statistical significance (p=0.42). CONCLUSIONS: We did not observe a significant difference in radiation dose delivered to subjects when comparing CT-guided foramen ovale cannulation relative to fluoroscopy for percutaneous lesioning of the Gasserian ganglion. Additional study is required under operational settings.

Cardiac angiogenesis directed by stable Hypoxia Inducible Factor-1.

BACKGROUND: The heterodimeric, oxygen-sensitive transcription factor Hypoxia Inducible Factor-1 (HIF-1) orchestrates angiogenesis and plays a key role in the response to ischemia and the growth of cancers. METHODS: We developed a transgenic mouse line in which expression of an oxygen-stable HIF-1α construct was controlled by a tetracycline-responsive promoter. HIF-1α expression was induced for up to 28 days in adult mouse heart, resulting in angiogenesis and progressive ventricular dysfunction. RESULTS: Gross inspection demonstrated enlarged hearts with large epicardial vessels with prominent side branches. Perfusion curves obtained by ultrasound contrast analysis demonstrated a significant increase in the myocardial red cell volume after 28 days of HIF-1α expression. Corrosion casts of cardiac vessels were made with a new low-viscosity resin that can fill the vasculature down to the level of the capillaries. Scanning electron microscopy of these casts reveal "lakes" of capillaries forming off of larger vessels after HIF expression, and support the rapid formation of mature neovascularization. Pro-angiogenic factors DLL-4, Notch-1, and PDGF-ß, were evaluated by immunohistochemistry and Western blots, and support a pattern of progressive functional neoangiogenesis. CONCLUSIONS: This study demonstrates the structural characteristics of HIF-directed angiogenesis and supports the utility of manipulation of HIF signaling to enhance perfusion and treat ischemia.