Axial Magnetic Resonance Angiography in Evaluating Revascularization after Indirect Bypass Surgery for Moyamoya Axial Magnetic Resonance Angiography after Indirect Bypass.

INTRODUCTION: At our institution, revascularization after indirect moyamoya surgery is routinely evaluated using magnetic resonance angiography (MRA) rather than catheter angiography. In this paper, we review how revascularization can be visualized on axial MRA and compare its visualization on MRA to that on catheter angiography. We also compare clinical outcomes of patients followed with routine postoperative MRA with outcomes of patients followed with routine catheter angiography. METHODS: We retrospectively reviewed the records of all patients treated at our institution who underwent unilateral encephaloduroarteriosynangiosis (EDAS) and/or pial synangiosis between the ages of 1 and 21 years and between December 31, 2003, and May 1, 2021. We included patients who underwent EDAS/pial synangiosis at other hospitals as long as they met all inclusion criteria. Inclusion criteria included having a preoperative MRA within 18 months of surgery and a postoperative MRA 3-30 months after surgery. Clinical outcomes included development of postoperative stroke and transient ischemic attacks (TIAs) and changes in symptoms (improved, unchanged, or worsened), including seizures, balance issues, and headaches. Clinical outcomes were compared between patients who had routine postoperative MRA only versus those who had routine postoperative angiograms, with or without routine MRA. For each surgery, we determined the ratios of the diameters and areas of the donor vessel and the contralateral corresponding vessel, as well as the relative signal intensities of these two vessels, on preoperative and 3- to 30-month postoperative MRA. We did the same for the middle meningeal artery (MMA) ipsilateral to the donor artery and the contralateral MMA. We assessed changes from pre- to post-operation in diameter ratios, area ratios, relative signal intensity, ivy sign, and in brain perfusion on arterial spin labeled (ASL) imaging. MRI and MRA measures of revascularization and flow were compared to Matsushima grades in patients who had postoperative catheter angiograms. RESULTS: Fifty-one operations for 42 unique patients were included. There were no significant differences in the rates of postoperative strokes, postoperative TIAs, changes in symptoms, or new symptoms after surgeries evaluated by routine postoperative MRA versus catheter angiogram (p = 0.282, 1, 0.664, and 0.727, respectively). There were significant associations between greater collateralization on postoperative MRA and greater median increases in preoperative-to-postoperative ratios of donor-vessel-over-contralateral-vessel diameter (p = 0.0461), ipsilateral-MMA-over-contralateral-MMA diameter (p = 0.0135), and the summed donor and ipsilateral MMA diameters over the summed contralateral vessel diameters (p < 0.001). The median increase in the ratio of the donor vessel and contralateral corresponding vessel diameters was significantly higher for Matsushima grade A versus B (p = 0.036). The median increase in the ratio of the sum of donor and ipsilateral MMA diameters over the sum of the contralateral vessel diameters was significantly higher for improved-versus-unchanged perfusion on ASL imaging (p = 0.0074). There was a nonsignificant association between greater postoperative collateralization on MRA and Matsushima grade (p = 0.1160). CONCLUSION: Cerebral revascularization after EDAS and pial synangiosis can be evaluated on axial MRA by comparing the diameter and/or signal intensity of the donor vessel and corresponding contralateral vessel, as well as the ipsilateral and contralateral MMA, on postoperative-versus-preoperative MRA. The use of routine postoperative MRA rather than catheter angiography does not appear to negatively affect outcomes.

Geographic Trends in the Neurosurgery Match During the COVID-19 Pandemic.

In the present article, the impact of the COVID-19 pandemic on geographical trends in the neurosurgery match in successfully matched applicants was analyzed. A cross-sectional analysis for the years from 2017 to 2021 was performed. Successful applicants' region, state, and medical school were compared with the location of their matched residency program. The number of applicants matching at a residency program within the same region or state as their home medical school or their own medical school was then evaluated. One hundred fifteen neurosurgery residency programs and 1066 successfully matched applicants were included in the analysis. When comparing 2021 with previous years, no significant change in the percentage of applicants matching at their home region (43.1% vs 49.7%, P = .09), home state (25.1% vs 26.3%, P = .69), or home program (19.9% vs 18.7%, P = .70) was found. The COVID-19 pandemic did not significantly affect geographic trends during the neurosurgery match in 2021. This is of note as the COVID-19 pandemic significantly affected the match in other competitive specialties, including plastic surgery, dermatology, and otolaryngology. Despite limited away rotations, it is possible that neurosurgery programs did not change their applicant selection criteria and implemented systems to virtually interact with applicants outside of their local region.

Erector Spinae Plane Block is Equivalent to Tumescent Local Anesthesia for Perioperative Pain Control with Abdominal Harvest for Fat Grafting.

There is increasing evidence that lidocaine is toxic to adipocytes and their precursors, which can contribute to the variability in fat graft resorption. Erector spinae plane (ESP) block is a new technique to provide analgesia of the trunk and would avoid lidocaine at the fat graft donor site. The aim of this study was to compare the efficacy of ESP block versus tumescent local anesthesia (TLA). Methods: A retrospective review was performed for all patients who underwent autologous fat grafting from the abdomen at the University of New Mexico Hospital between February 2016 and March 2019. These patients received either ESP block or TLA during abdominal fat harvest. The primary endpoints were intraoperative, postoperative, and total morphine equivalents. Results: There was no difference in the mean intraoperative, postoperative, and total morphine equivalents administered between the ESP and TLA groups. Conclusions: ESP block is equivalent to TLA for analgesia when using an abdominal donor site for fat harvest. ESP block should be considered in fat-grafting cases to avoid the potential toxicity of lidocaine to the viability of adipocytes and preadipocytes.

Botulinum Toxin A for the Treatment of Sympathomimetic Pressor-Induced Digital Hand Ischemia in the Critically Ill Intensive Care Unit Patient.

Vasopressor-induced ischemia of the hand, while relatively rare, is a severe complication in critically ill intensive care unit (ICU) patients requiring high concentrations of sympathomimetic pressors and often results in digit necrosis and amputation. Currently, there are no widely accepted approaches for treating this cause of peripheral digital ischemia. Case reports have demonstrated that reducing the concentration of vasopressors that patients are given may reverse the progression of ischemic events prior to necrosis. While this approach is at odds with the principle of "life over limb," it demonstrates that digit necrosis can be reversed, resulting in improved outcomes. Here, we present a therapeutic strategy for treating digital limb ischemia in the septic ICU patient without the need to lower systemic vasopressor dose by using locally injected botulinum toxin A into ischemic hands.

Pavement Burns in New Mexico: Our Experiences, Treatments, and Outcomes.

This study focused on patients treated at the University of New Mexico Burn Center who sustained burn injuries from contact with environmentally heated pavement. We report on our patient demographics and outcomes as well as describe our institutional staged surgical approach to treatment. We provide a comparison of our results with other case reports as well as other findings. A retrospective review of patients admitted to the University of New Mexico Burn Center with injuries suffered from contact with hot pavement was performed. Patients were stratified on the presence or absence of altered mental status (AMS) and additional inciting factors. A total of six patients were reviewed from 2018 to 2019. We looked at patient demographics and comorbidities, time of contact with hot pavement, inciting factors, total body surface area (TBSA) burned, location of areas burned, depth of burn injury at the time of presentation and at the time of initial operative debridement, percentage of autograft take, complications, length of stay (LOS), and final disposition. The patients in our study had a mean TBSA of 9.82% corresponding to pressure points of the body. All patients had nearly 100% conversion to full-thickness burns at the time of initial operative debridement. With staged excision and split-thickness autografting, our patients had nearly 100% take of their skin grafts with minimal graft loss or related complications. At the time of presentation, 100% of patients had AMS and 66% (4/6) had a drug- or alcohol-related inciting event. Finally, the average LOS was 19.5 days in comparison to 7 to 9 days for uncomplicated burns of equivalent size at our burn center. Despite an initial appearance of a partial-thickness burn, pavement burns had a high propensity to convert to full-thickness burns. Patients with AMS contributed to our patient population being found with pavement burns. Patients with pavement burns had a distinct anatomic pattern corresponding to pressure points of the body which were often areas at high risk for skin and wound breakdown and complications. Staged excision and split-thickness autografting in the treatment of pavement burns yielded excellent results. Finally, our data showed that providers must be prepared for an extended LOS for patients with pavement burns.

Persistent nipple discharge after nipple-sparing mastectomy secondary to unincorporated AlloDerm: a case report.

BACKGROUND: Rates of nipple-sparing mastectomies have increased over the past decade. In 2017, acellular dermal matrix was used in 56% of breast reconstructive procedures, with complication rates similar to operations without AlloDerm. Although persistent nipple discharge after nipple-sparing mastectomy is a rare event, it has been described in the literature. Other authors have described evaluation and treatment on a case-by-case basis. To the best of our knowledge, this is the first case report to describe a persistent unilateral discharge after multiple operative revisions and to provide an algorithmic approach to workup and treatment. CASE PRESENTATION: We present a case of a 29-year-old Hispanic woman with BRCA1 mutation who underwent a prophylactic bilateral nipple-sparing mastectomy with immediate reconstruction using AlloDerm. The year following her operation, the patient underwent two surgical revisions, one for implant rippling and one for asymmetry. Six months after her second revision, she presented to our hospital with a capsular contracture and unilateral clear nipple discharge. Her breast ultrasound showed dilated subareolar ducts and a suspicious mass. Magnetic resonance imaging identified a benign-appearing, rim-enhancing fluid collection. She underwent a third revision. One year later, she returned to our clinic with bloody nipple discharge, erythematous skin changes, and a palpable breast lump. Her surgical biopsy showed a fold in AlloDerm and chronic inflammatory changes. She continued experiencing discharge and opted for nipple excision. During the operation, a lacrimal probe demonstrated a direct connection between the discharging external duct and a seroma associated with an area of unincorporated AlloDerm. The section of unincorporated AlloDerm was excised, and no evidence of malignancy was identified. Ten months later, the patient remained symptom-free and had progressed to placement of final silicone implants. CONCLUSIONS: To the best of our knowledge, this is the first case report to describe a nongravid patient with persistent unilateral sanguineous nipple discharge after multiple operative revisions. A visible communication between the draining duct and a seroma associated with unincorporated AlloDerm was ultimately identified. We present a clinical algorithm for patients with nipple discharge after nipple-sparing mastectomy.

Botulinum Toxin A Salvage of Ischemic Hand Trauma.

Posttraumatic hand injuries from crush injury, infusion, or iatrogenic vascular cannulation can cause ischemic finger damage that can progress to necrosis and digital amputation. Botulinum toxin type A (Botox) improves blood flow in chronic vasospastic disorders of the hand. Botox's efficacy in salvaging ischemic loss in digits in acute traumatic and iatrogenic injury has not been previously reported. From February of 2015 to December of 2016, 11 patients at a Level I trauma center (West Virginia University) presented to the hand surgery service with early ischemic injury and vascular compromise to hand and fingers as a result of crush, direct drug injection, or proximal arterial injury from drug injection or catheterization. Before 2015, all patients with vascular compromise were treated with standard protocol. After January of 2016, patients were treated with additional injection of 80 to 100 U of Botox into the palm and wrist. Before administration of Botox, six patients with vascular compromise of one or more fingers were treated with a conservative protocol and 83 percent had amputation of necrotic digits. After January of 2016, five patients with ischemia were treated with Botox into the palm and proximal arteries. All Botox-treated digits were preserved (100 percent salvage). Pain scores were lower in Botox-treated fingers. We conclude that (1) in the acute traumatic vascular hand injury, early Botox injection markedly increases digital salvage; (2) direct nerve effects after Botox injections improve postinjury pain scores; and (3) early use of Botox in finger injuries is our standard approach to impending ischemia in the hand.

Prolonged delayed vasospasm in the setting of nonaneurysmal intraventricular hemorrhage.

BACKGROUND: Though still thought to be rare, in recent years, vasospasm as a result of primary intraventricular hemorrhage (IVH) has been increasingly recognized in patients with spontaneous primary intraventricular hemorrhage, of various etiologies. Unlike vasospasm in aneurysmal subarachnoid hemorrhage (SAH), which has a well-defined time frame of 3-21 days, such a window is poorly defined for primary spontaneous intraventricular hemorrhage from other vascular etiologies. CASE DESCRIPTION: We report on two cases of prolonged delayed proximal intracranial cerebral vasospasm occurring 29 and 22 days after the initial presentation. CONCLUSION: To our knowledge, this is the first report of such delayed vasospasm in spontaneous primary intraventricular hemorrhage secondary to a dural arteriovenous fistula and cavernous malformation. Our two cases of vasospasm in patients with nontraumatic nonaneurysmal SAH with IVH presented outside the expected time period of 21 days. It is important to recognize that symptomatic vasospasm secondary to intraventricular hemorrhage is a rare but devastating complication that can have serious deleterious consequences if gone unrecognized and untreated.

Automating neurosurgical tumor resection surgery: Volumetric laser ablation of cadaveric porcine brain with integrated surface mapping.

OBJECTIVE: Current surgical instruments for soft tissue resection including neurosurgical procedures rely on the accuracy and precision of the human operator and are fundamentally constrained by the human hand. Automated surgical action with the integration of intraoperative data sources can enable highly accurate and fast tissue manipulation using laser ablation. This study presents the first experiments with a prototype designed for automated tumor resection via laser ablation. We demonstrate targeted soft tissue resection in porcine brain with an integrated device that combines 3D scanning capabilities with a steerable surgical laser and discuss implications for future automated robotic neurosurgical procedures. STUDY DESIGN AND METHODS: A device consisting of a two-axis galvanometer for steering a cutting laser and a 3D surface profiler is used to perform volumetric removal of tissue of ex vivo porcine brain. Three-dimensional surface profiles are gathered between cuts and used to estimate ablation rate. RESULTS: Volumetric ablation of porcine brain tissue is performed and subsequently surface profiled. The average ablation rates across the area cutting areas were 2.6 mm3 /s and 3.7 mm3 /s for the initial and subsequent cuts, respectively. A Kruskal-Wallis and post-hoc Tukey test show statistical significance between the initial and subsequent cuts. Accuracy between cuts when benchmarked against a human surgeon varied from 47 to 88%. CONCLUSION: A feed-forward volumetric resection is demonstrated with sensing and cutting housed within a single device, thereby opening the potential for automated soft tissue resection as necessary during the surgical removal of pathologic tissues. High variance around target cut depths motivates future work in developing a closed-loop ablation tool as well as characterization of laser-tissue interactions for predictive modelling. Objective Lasers Surg. 50:1017-1024, 2018. © 2018 Wiley Periodicals, Inc.

Drivers and Risk Factors of Unplanned 30-Day Readmission Following Spinal Cord Stimulator Implantation.

OBJECTIVES: Unplanned 30-day readmission rates contribute significantly to growing national healthcare expenditures. Drivers of unplanned 30-day readmission after spinal cord stimulator (SCS) implantation are relatively unknown. The aim of this study was to determine drivers of 30-day unplanned readmission following SCS implantation. METHODS: The National Readmission Database was queried to identify all patients who underwent SCS implantation for the 2013 calendar year. Patients were grouped by readmission status, "No Readmission" and "Unplanned 30-day Readmission." Patient demographics and comorbidities were collected for each patient. The primary outcome of interest was the rate of unplanned 30-day readmissions and associated driving factors. A multivariate analysis was used to determine independent predictors of unplanned 30-day readmission after SCS implantation. RESULTS: We identified 1521 patients who underwent SCS implantation, with 113 (7.4%) experiencing an unplanned readmission within 30 days. Baseline patient demographics, comorbidities, and hospital characteristics were similar between both cohorts. The three main drivers for 30-day readmission after SCS implantation include: 1) infection (not related to SCS device), 2) infection due to device (limited to only hardware infection), and 3) mechanical complication of SCS device. Furthermore, obesity was found to be an independent predictor of 30-day readmission (OR: 1.86, p = 0.008). CONCLUSION: Our study suggests that infectious and mechanical complications are the primary drivers of unplanned 30-day readmission after SCS implantation, with obesity as an independent predictor of unplanned readmission. Given the technological advancements in SCS, repeated studies are necessary to identify factors associated with unplanned 30-day readmission rates after SCS implantation to improve patient outcomes and reduce associated costs.

Incidental choroid plexus papilloma in a child: A difficult decision.

BACKGROUND: Choroid plexus tumors (CPT) in the pediatric population are usually discovered in symptomatic patients often with symptoms of increased intracranial pressure, with hydrocephalus as the most common presentation, along with seizures, subarachnoid hemorrhage, or focal neurological deficit. Most CPTs are found to be benign choroid plexus papillomas (CPP), whereas a small number are intermediate and malignant choroid plexus carcinomas (CPC). Total surgical resection is the established definitive treatment for symptomatic CPP. CASE DESCRIPTION: We describe a young female who was found to have an incidental CPT during workup for recent head trauma without neurological deficits or hydrocephalus. She underwent a surgical operation to remove the tumor successful, with 1-year follow-up showing no recurrence and normal developmental milestones. CONCLUSION: This rare presentation of an asymptomatic CPT brings attention to the fact that there is no clear evidence for how or when to treat such patients. Because discovery of a CPT in an asymptomatic patient is uncommon, the treatment plan appears to be developed on a case-by-case basis. We hope to generate discussion for establishing an agreed upon treatment approach for CPTs in asymptomatic patients.

Maxillary Artery to Middle Cerebral Artery Bypass: A Novel Technique for Exposure of the Maxillary Artery.

OBJECTIVE: To define the maxillary artery (MaxA) anatomy and present a novel technique for exposing and preparing this vessel as a bypass donor. METHODS: Cadaveric and radiologic studies were used to define the MaxA anatomy and show a novel method for harvesting and preparing it for extracranial to intracranial bypass. RESULTS: The MaxA runs parallel to the frontal branch of the superficial temporal artery and is located on average 24.8 ± 3.8 mm inferior to the midpoint of the zygomatic arch. The pterygoid segment of the MaxA is most appropriate for bypass with a maximal diameter of 2.5 ± 0.4 mm. The pterygoid segment can be divided into a main trunk and terminal part based on anatomic features and use in the bypass procedure. The main trunk of the pterygoid segment can be reached extracranially, either by following the deep temporal arteries downward toward their origin from the MaxA or by following the sphenoid groove downward to the terminal part of the pterygoid segment, which can be followed proximally to expose the entire MaxA. In comparison, the prebifurcation diameter of the superficial temporal artery is 1.9 ± 0.5 mm. The average lengths of the mandibular and pterygoid MaxA segments are 6.3 ± 2.4 and 6.7 ± 3.3 mm, respectively. CONCLUSIONS: The MaxA can be exposed without zygomatic osteotomies or resection of the middle fossa floor. Anatomic landmarks for exposing the MaxA include the anterior and posterior deep temporal arteries and the pterygomaxillary fissure.

Somatosensory evoked potential monitoring detection of carotid compression during ACDF surgery in a patient with a vascularly isolated hemisphere.

The authors report herein a case of anterior cervical discectomy and fusion (ACDF) surgery in which findings on somatosensory evoked potential (SSEP) monitoring led to the correction of carotid artery compression in a patient with a vascularly isolated hemisphere (no significant collateral blood vessels to the carotid artery territory). The amplitude of the cortical SSEP component to left ulnar nerve stimulation progressively decreased in multiple runs, but there were no changes in the cervicomedullary SSEP component to the same stimulus. When the lateral (right-sided) retractor was removed, the cortical SSEP component returned to baseline. The retraction was then intermittently relaxed during the rest of the operation, and the patient suffered no neurological morbidity. Magnetic resonance angiography demonstrated a vascularly isolated right hemisphere. During anterior cervical spine surgery, carotid artery compression by the retractor can cause hemispheric ischemia and infarction in patients with inadequate collateral circulation. The primary purpose of SSEP monitoring during ACDF surgery is to detect compromise of the dorsal column somatosensory pathways within the cervical spinal cord, but intraoperative SSEP monitoring can also detect hemispheric ischemia. Concurrent recording of cervicomedullary SSEPs can help differentiate cortical SSEP changes due to hemispheric ischemia from those due to compromise of the dorsal column pathways. If there are adverse changes in the cortical SSEPs but no changes in the cervicomedullary SSEPs, the possibility of hemispheric ischemia due to carotid artery compression by the retractor should be considered.