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Peter F. Morgenstern and Jared Knopman

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Jared Knopman, A. John Tsiouris, and Mark M. Souweidane

Venous sinus thrombosis is a rare entity that usually arises secondary to underlying thrombophilia, neoplasm, head injury, or infection. Tympanic infection accounts for the majority of infectious etiologies, and the sigmoid sinus becomes the likely anatomical site of thrombosis. The authors report a case involving a child with recurrent otitis media who presented with an atraumatic epidural hematoma secondary to sigmoid sinus thrombosis. Intraoperative evaluation revealed epidural hemorrhage that originated from the venous sinus, with hemorrhagic products of varying ages. To the authors' knowledge, this is the first reported case of a venous sinus thrombosis resulting in an epidural hematoma.

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Karishma Parikh, Andre Tomasino, Jared Knopman, John Boockvar, and Roger Härtl

Object

The authors present their clinical results and the learning curve associated with the use of tubular retractors for 1- and 2-level lumbar microscope-assisted discectomies and laminectomies.

Methods

The study involves a retrospective and prospective analysis of 230 patients who underwent noninstrumented minimally invasive procedures for degenerative lumbar spinal disease between 2004 and 2007. Data on patient demographic characteristics and operative results, including length of stay, blood loss, operative times, and surgical complications were collected. Clinical outcomes were assessed based on pre- and postoperative Visual Analog Scale scores, Oswestry Disability Index values, and the Macnab outcome scale scores.

Results

The results showed characteristic differences in blood loss and operating times between 1- and 2-level procedures and between discectomies and laminectomies. A significant learning curve was seen by a decrease in operating time for 1- level discectomies and 2-level laminectomies. Major complications were not observed.

Conclusions

The use of tubular retractors for microsurgical decompression of degenerative spinal disease is a safe and effective treatment modality. As with other techniques, minimally invasive procedures are associated with a significant learning curve. As surgeons become more comfortable with the procedure, its applications can be expanded to include, for example, spinal instrumentation and deformity correction.

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George Chater-Cure, Caitlin Hoffman, Jared Knopman, Samuel Rhee, and Mark M. Souweidane

Object

Surgical treatment for periorbital inclusion cysts typically involves a brow, pterional, or partial bicoronal scalp incision for sufficient exposure. The authors have recently employed an endoscopy-assisted technique as an alternative approach intended to minimize the length of the skin incision and avoid scarring in the brow.

Methods

Children having typical clinical findings of a dermoid cyst located on the hairless forehead were selected to undergo endoscopy-assisted cyst removal. For suspected intradiploic lesions, MR imaging was used to assess osseous involvement. After induction of general anesthesia, a 1–2-cm curvilinear incision was made posterior to the hairline. A 30°-angled endoscope (4 mm) was then used for dissection in the subgaleal compartment. Subgaleal dissection was followed by a circumferential periosteal incision in which the authors used an angled needle-tip unipolar cautery. For lesions within the diploe, a high-speed air drill was used to expose the lesion. Complete removal was accomplished with curettage of either the skull or dural surface.

Results

Eight patients (5–33 months of age) underwent outpatient endoscopic resection. Seven cysts were extracranial, and 1 cyst extended through the inner table. In all patients complete excision of the cyst was achieved. There was negligible blood loss, no dural violation, and no postoperative infection. There have been no recurrences at a mean follow-up of 15 months.

Conclusions

Endoscopy-assisted resection of inclusion cysts of the scalp and calvaria is a safe and effective surgical approach. The technique results in negligible incisions with less apparent scarring compared with previously described incisions. This limited-access technique does not appear to be associated with a higher incidence of cyst recurrence.

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Justin Schwarz, Joseph A. Carnevale, Jacob L. Goldberg, Alexander D. Ramos, Thomas W. Link, and Jared Knopman

OBJECTIVE

Chronic subdural hematoma (cSDH) is a common and challenging pathology to treat due to both the historically high recurrence rate following surgical evacuation and the medical comorbidities inherent in the aging patient population that it primarily affects. Middle meningeal artery (MMA) embolization has shown promise in the treatment of cSDHs, most convincingly to avoid surgical evacuation in relatively asymptomatic patients. Symptomatic patients requiring surgical evacuation may also benefit from perioperative MMA embolization to prevent cSDH recurrence. The goal of this study was to determine the utility of perioperative MMA embolization for symptomatic cSDH requiring surgical evacuation and to assess if there is a decrease in the cSDH recurrence rate compared to historical recurrence rates following surgical evacuation alone.

METHODS

Symptomatic cSDHs were evacuated using a subdural evacuating port system (SEPS) with 5-mm twist-drill craniostomy in an intensive care unit or by performing a craniotomy in the operating room, using either a small (silver dollar, < 4 cm) or large (≥ 4 cm) craniotomy. MMA embolization was performed perioperatively using angiography, selective catheterization of the MMA, and infusion of polyvinyl particles. Outcomes were assessed clinically and radiographically with interval head CT imaging.

RESULTS

There were 44 symptomatic cSDHs in 41 patients, with 3 patients presenting with bilateral symptomatic cSDH. All cSDHs were evacuated using an SEPS (n = 18), a silver-dollar craniotomy (n = 16), or a large craniotomy (n = 10). Prophylactic MMA embolization was performed successfully in all cSDHs soon after surgical evacuation. There were no deaths and no procedural complications. There was an overall reduction of greater than 50% or resolution of cSDH in 40/44 (90.9%) cases, regardless of the evacuation procedure used. Of the 44 prophylactic cases, there were 2 (4.5%) cases of cSDH recurrence that required repeat surgical evacuation at the 1-year follow-up. These 2 cSDHs were initially evacuated using an SEPS and subsequently required a craniotomy, thereby representing an overall 4.5% recurrence rate of treated cSDH requiring repeat evacuation. Most notably, of the 26 patients who underwent surgical evacuation with a craniotomy followed by MMA embolization, none had cSDH recurrence requiring repeat intervention.

CONCLUSIONS

Perioperative prophylactic MMA embolization in the setting of surgical evacuation, via either craniotomy or SEPS, may help to lower the recurrence rate of cSDH.

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Fatima A. Sehba, Gulam Mostafa, Jared Knopman, Victor Friedrich Jr., and Joshua B. Bederson

Object. Aneurysmal subarachnoid hemorrhage (SAH) causes acute and delayed ischemic brain injuries. The mechanisms of acute ischemic injury following SAH are poorly understood, although an acute increase in microvascular permeability has been noted. The integrity of cerebral microvessels is maintained in part by components of basal lamina: collagen IV, elastin, lamina, and so forth. Destruction of basal lamina components by collagenases and matrix metalloproteinases (MMPs), especially MMP-9, has been known to occur in other ischemic models. The authors assessed the integrity of cerebral microvasculature after acute SAH by examining collagen IV and MMP-9 levels and collagenase activity in the microvessels.

Methods. Subarachnoid hemorrhage was induced in rats through endovascular perforation of the intracranial bifurcation of the internal carotid artery. Animals were killed 10 minutes to 48 hours after SAH or sham operation (time-matched controls). Levels of collagen IV and MMP-9 were studied in the microvasculature by performing immunoperoxidase and immunofluorescence staining, and collagenase activity was assessed by in situ zymography.

Little change occurred in collagen IV and MMP-9 immunostaining or collagenase activity at 10 minutes or 1 hour after SAH. Starting 3 hours after SAH, collagen IV immunostaining was reduced or eliminated along segments of microvessels whereas MMP-9 staining was segmentally increased. These effects reached a maximum at 6 hours and returned toward those values in sham-operated controls at 48 hours.

Conclusions. Results of this study demonstrated an acute loss of collagen IV from the cerebral microvasculature after SAH and indicated that MMP-9 contributes to this event. The loss of collagen IV might contribute to the known failure of the blood—brain barrier after SAH.

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Heather J. McCrea, Jana Ivanidze, Ashley O’Connor, Eliza H. Hersh, John A. Boockvar, Y. Pierre Gobin, Jared Knopman, and Jeffrey P. Greenfield

OBJECTIVE

Delivery of drugs intraarterially to brain tumors has been demonstrated in adults. In this study, the authors initiated a phase I trial of superselective intraarterial cerebral infusion (SIACI) of bevacizumab and cetuximab in pediatric patients with refractory high-grade glioma (diffuse intrinsic pontine glioma [DIPG] and glioblastoma) to determine the safety and efficacy in this population.

METHODS

SIACI was used to deliver mannitol (12.5 ml of 20% mannitol) to disrupt the blood-brain barrier (BBB), followed by bevacizumab (15 mg/kg) and cetuximab (200 mg/m2) to target VEGF and EGFR, respectively. Patients with brainstem tumors had a balloon inflated in the distal basilar artery during mannitol infusion.

RESULTS

Thirteen patients were treated (10 with DIPG and 3 with high-grade glioma). Toxicities included grade I epistaxis (2 patients) and grade I rash (2 patients). There were no dose-limiting toxicities. Of the 10 symptomatic patients, 6 exhibited subjective improvement; 92% showed decreased enhancement on day 1 posttreatment MRI. Of 10 patients who underwent MRI at 1 month, 5 had progressive disease and 5 had stable disease on FLAIR, whereas contrast-enhanced scans demonstrated progressive disease in 4 patients, stable disease in 2, partial response in 2, and complete response in 1. The mean overall survival for the 10 DIPG patients was 519 days (17.3 months), with a mean posttreatment survival of 214.8 days (7.2 months).

CONCLUSIONS

SIACI of bevacizumab and cetuximab was well tolerated in all 13 children. The authors’ results demonstrate safety of this method and warrant further study to determine efficacy. As molecular targets are clarified, novel means of bypassing the BBB, such as intraarterial therapy and convection-enhanced delivery, become more critical.

Clinical trial registration no.: NCT01884740 (clinicaltrials.gov)

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Alexander Ramos, Joseph A. Carnevale, Kashif Majeed, Gary Kocharian, Ibrahim Hussain, Jacob L. Goldberg, Justin Schwarz, David I. Kutler, Jared Knopman, and Philip Stieg

OBJECTIVE

Carotid body tumors (CBTs) are rare, slow-growing neoplasms derived from the parasympathetic paraganglia of the carotid bodies. Although inherently vascular lesions, the role of preoperative embolization prior to resection remains controversial. In this report, the authors describe an institutional series of patients with CBT successfully treated via resection following preoperative embolization and compare the results in this series to previously reported outcomes in the treatment of CBT.

METHODS

All CBTs resected between 2013 and 2019 at a single institution were retrospectively identified. All patients had undergone preoperative embolization performed by interventional neuroradiologists, and all had been operated on by a combined team of cerebrovascular neurosurgeons and otolaryngology–head and neck surgeons. The clinical, radiographic, endovascular, and perioperative data were collected. All procedural complications were recorded.

RESULTS

Among 22 patients with CBT, 63.6% were female and the median age was 55.5 years at the time of surgery. The most common presenting symptoms included a palpable neck mass (59.1%) and voice changes (22.7%). The average tumor volume was 15.01 ± 14.41 cm3. Most of the CBTs were Shamblin group 2 (95.5%). Blood was predominantly supplied from branches of the ascending pharyngeal artery, with an average of 2 vascular pedicles (range 1–4). Fifty percent of the tumors were embolized with more than one material: polyvinyl alcohol, 95.5%; Onyx, 50.0%; and N-butyl cyanoacrylate glue, 9.1%. The average reduction in tumor blush following embolization was 83% (range 40%–95%). No embolization procedural complications occurred. All resections were performed within 30 hours of embolization. The average operative time was 173.9 minutes, average estimated blood loss was 151.8 ml, and median length of hospital stay was 4 days. The rate of permanent postoperative complications was 0%; 2 patients experienced transient hoarseness, and 1 patient had medical complications related to alcohol withdrawal.

CONCLUSIONS

This series reveals that endovascular embolization of CBT is a safe and effective technique for tumor devascularization, making preoperative angiography and embolization an important consideration in the management of CBT. Moreover, the successful management of CBT at the authors’ institution rests on a multidisciplinary approach whereby endovascular surgeons, neurosurgeons, and ear, nose, and throat–head and neck surgeons work together to optimally manage each patient with CBT.

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Ryan E. Radwanski, Brandon R. Christophe, Josephine U. Pucci, Moises A. Martinez, Michael Rothbaum, Emilia Bagiella, Franklin D. Lowy, Jared Knopman, and E. Sander Connolly Jr.

OBJECTIVE

Postoperative surgical site infections (SSIs) in neurosurgical patients carry a significant risk of increased morbidity and mortality. With SSIs accounting for approximately 20% of nosocomial infections and costing approximately $1.6 billion USD annually, there is a need for additional prophylaxis to improve current standards of care. Topical vancomycin is increasingly utilized in instrumented spinal and cardiothoracic procedures, where it has been shown to reduce the risk of SSIs. A randomized controlled trial assessing its efficacy in the general neurosurgical population is currently underway. Here, the authors report their initial impressions of topical vancomycin safety among patients enrolled during the 1st year of the trial.

METHODS

This prospective, multicenter, patient-blinded, randomized controlled trial will enroll 2632 patients over 5 years. Here, the authors report the incidence of adverse events, the degree of systemic vancomycin absorption in treated patients, and pattern changes of antibiotic-resistant profiles of Staphylococcus aureus flora among patients enrolled during the 1st year.

RESULTS

The topical vancomycin treatment group comprised 257 patients (514 total enrolled patients), of whom 2 exhibited weakly positive serum levels of vancomycin (> 3.0 mg/dl). S. aureus was detected preoperatively in the anterior nares of 35 (18.1%) patients and the skin near the surgical site of 9 (4.7%). Colonization in the nares remained for many patients (71.4%) through postoperative day 30. The authors found a significant association between preoperative S. aureus colonization and postoperative colonization. Seven methicillin-resistant isolates were detected among 6 different patients. Two isolates were detected preoperatively, and 5 were de novo postoperative colonization. No adverse responses to treatment have been reported to date.

CONCLUSIONS

The authors’ data indicate that the use of topical vancomycin is safe with no significant adverse effects and minimal systemic absorption, and no development of vancomycin-resistant microorganisms.

Clinical trial registration no.: NCT02284126 (clinicaltrials.gov)

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Jennifer A. Moliterno, Jared Knopman, Karishma Parikh, Jessica N. Cohan, Q. Daisy Huang, Grant D. Aaker, Anastasia D. Grivoyannis, Ashwin R. Patel, Roger Härtl, and John A. Boockvar

Object

The use of minimally invasive surgical techniques, including microscope-assisted tubular lumbar microdiscectomy (tLMD), has gained increasing popularity in treating lumbar disc herniations (LDHs). This particular procedure has been shown to be both cost-efficient and effective, resulting in outcomes comparable to those of open surgical procedures. Lumbar disc herniation recurrence necessitating reoperation, however, remains an issue following spinal surgery, with an overall reported incidence of approximately 3–13%. The authors' aim in the present study was to report their experience using tLMD for single-level LDH, hoping to provide further insight into the rate of surgical recurrence and to identify potential risk factors leading to this complication.

Methods

The authors retrospectively reviewed the cases of 217 patients who underwent tLMD for single-level LDH performed identically by 2 surgeons (J.B., R.H.) between 2004 and 2008. Evaluation for LDH recurrence included detailed medical chart review and telephone interview. Recurrent LDH was defined as the return of preoperative signs and symptoms after an interval of postoperative resolution, in conjunction with radiographic demonstration of ipsilateral disc herniation at the same level and pathological confirmation of disc material. A cohort of patients without recurrence was used for comparison to identify possible risk factors for recurrent LDH.

Results

Of the 147 patients for whom the authors were able to definitively assess symptomatic recurrence status, 14 patients (9.5%) experienced LDH recurrence following single-level tLMD. The most common level involved was L5–S1 (42.9%) and the mean length of time to recurrence was 12 weeks (range 1.5–52 weeks). Sixty-four percent of the patients were male. In a comparison with patients without recurrence, the authors found that relatively lower body mass index was significantly associated with recurrence (p = 0.005), such that LDH in nonobese patients was more likely to recur.

Conclusions

Recurrence rates following tLMD for LDH compare favorably with those in patients who have undergone open discectomy, lending further support for its effectiveness in treating single-level LDH. Nonobese patients with a relatively lower body mass index, in particular, appear to be at greater risk for recurrence.