Exploring the Role of the Pulvinar Nucleus of the Thalamus in Occipital Lobe Epilepsy: A Case Report

Understanding the role of the pulvinar nucleus may be critical for guiding circuit-targeted neurosurgical intervention in some patients. In this report, a 33-year-old female presented with focal onset occipital epilepsy with secondary generalization and with a previously radiated arteriovenous malformation within the right primary visual cortex. Phase II monitoring demonstrated the pulvinar nucleus was not involved in subclinical seizures restricted to the primary visual cortex, but it did become involved in clinical events with more extensive seizure spread into higher visual cortical regions. She underwent responsive neurostimulation (RNS) with implantation of leads within the primary visual cortex. This case demonstrates the late propagation of epileptic activity from the visual cortex to the pulvinar nucleus and illustrates the pulvinar nucleus' connections with higher-order visual areas.

The Surgical Histopathology of the Filum Terminale: Findings from a Large Series of Patients with Tethered Cord Syndrome

This study investigated the prevalence of embryonic and connective tissue elements in the filum terminale (FT) of patients with tethered cord syndrome (TCS), examining both typical and pathological histology. The FT specimens from 288 patients who underwent spinal cord detethering from 2013 to 2021 were analyzed. The histopathological examination involved routine hematoxylin and eosin staining and specific immunohistochemistry when needed. The patient details were extracted from electronic medical records. The study found that 97.6% of the FT specimens had peripheral nerves, and 70.8% had regular ependymal cell linings. Other findings included ependymal cysts and canals, ganglion cells, neuropil, and prominent vascular features. Notably, 41% showed fatty infiltration, and 7.6% had dystrophic calcification. Inflammatory infiltrates, an underreported finding, were observed in 3.8% of the specimens. The research highlights peripheral nerves and ganglion cells as natural components of the FT, with ependymal cell overgrowth and other tissues potentially linked to TCS. Enlarged vessels may suggest venous congestion due to altered FT mechanics. The presence of lymphocytic infiltrations and calcifications provides new insights into structural changes and mechanical stress in the FT, contributing to our understanding of TCS pathology.

Microsurgical approach for resection of the filum terminale internum in tethered cord syndrome-a case demonstration of technical nuances and vignettes

BACKGROUND

In tethered cord syndrome due to filum terminale pathology, the surgical approach to achieve detethering of the spinal cord may vary. Traditionally, sectioning the filum through a laminectomy at the lumbosacral level is performed.

METHOD

A microsurgical technique at a higher level to approach the filum below the conus tip is performed. This allows for removal of the entire distal portion of the filum through a limited interlaminar approach and dural opening.

CONCLUSION

We propose a technique to transect the filum terminale below the conus tip and extract the distal filum by releasing it from its intradural attachments to minimize any remnants of the filum terminale.

Seizure and anatomical outcomes of repeat laser amygdalohippocampotomy for temporal lobe epilepsy: A single-institution case series

OBJECTIVE

In patients with treatment-refractory temporal lobe epilepsy (TLE), a single stereotactic laser interstitial thermotherapy (LITT) procedure is sometimes insufficient to ablate epileptogenic tissue, particularly the medial structures often implicated in TLE. In patients with seizure recurrence after initial ablation, the extent to which a second ablation may achieve improved seizure outcomes is uncertain. The objective of this study was to investigate the feasibility and potential efficacy of repeat LITT amygdalohippocampotomy as a worthwhile strategy for intractable temporal lobe epilepsy by quantifying changes to targeted mesial temporal lobe structures and seizure outcomes.

METHODS

Patients who underwent two LITT procedures for drug-resistant mesial TLE at our institution were included in the study. Lesion volumes for both procedures were calculated by comparing post-ablation intraoperative sequences to preoperative anatomy. Clinical outcomes after the initial procedure and repeat procedure were classified according to Engel scores.

RESULTS

Five consecutive patients were included in this retrospective case series: 3 with right- and 2 with left-sided TLE. The median interval between LITT procedures was 294 days (range: 227-1918). After the first LITT, 3 patients experienced class III outcomes, 1 experienced a class IV, and 1 experienced a class IB outcome. All patients achieved increased seizure freedom after a second procedure, with class I outcomes (3 IA, 2 IB).

CONCLUSIONS

Repeat LITT may be sufficient to achieve satisfactory seizure outcomes in some individuals who might otherwise be considered for more aggressive resection or palliative neuromodulation. A larger study to establish the potential value of repeat LITT amygdalohippocampotomy vs. other re-operation strategies for persistent, intractable temporal lobe epilepsy is worth pursuing.

Metastatic cervical carcinoma to the brain masquerading as a butterfly glioma: A case report

Background

Metastatic cervical cancer to the brain is a rare occurrence, representing approximately 1.5% of metastatic cases. We report a rare presentation of cervical cancer with brain metastasis to the corpus callosum. The patient was initially suspected to have a primary glioma but was diagnosed with a metastatic cervical carcinoma lesion through both stereotactic and then opens biopsy.

Case Description

A 53-year-old female, with Stage III adenosquamous cervical carcinoma, presented with a large heterogeneously enhancing mass in the corpus callosum body with extension in the cingulate gyrus concerning for glioma. A stereotactic biopsy revealed hypercellular and gliotic brain tissue, while an open biopsy showed an epithelioid neoplasm consistent with metastatic cervical adenosquamous carcinoma. The patient underwent a craniotomy and recovered well and was discharged in stable condition.

Conclusion

Brain metastases from cervical cancer are uncommon. We present a rare case of metastatic cervical carcinoma which appeared on imaging to mimic a butterfly glioma. The patient's history and histopathological examination were essential in determining the correct diagnosis and receiving timely treatment.

Minimizing blood loss with direct percutaneous polymethylmethacrylate embolization before corpectomy for vascular spinal tumors

Background

Standard surgical treatment for vascular spinal tumors, including renal cell carcinomas and hemangiomas, may result in significant blood loss despite preoperative arterial tumor embolization.

Methods

This is a retrospective review of 12 patients who underwent direct percutaneous polymethylmethacrylate embolization (DPPE) with or without feeding artery embolization before partial or complete corpectomy for the resection of vascular spinal tumors (2013-2018). Estimated blood loss (EBL) was compared to the blood loss reported in the literature and to patients receiving standard arterial embolization before surgery.

Results

The mean EBL for 12 patients was 1030 mL; three of 12 patients required blood transfusions. For the single level corpectomies, the EBL ranged from 100 mL to 3900 mL (mean 640 mL). This mean blood loss was not increased in patients receiving only DPPE preoperatively versus those patients receiving preoperative arterial embolization in addition to DPPE (1005 vs. 1416 mL); in fact, the EBL was significantly reduced for those undergoing DPPE alone.

Conclusion

In this initial study, nine patients treated with DPPE embolization alone before spinal tumor resection demonstrated reduction of intraoperative blood loss compared to three patients having arterial embolization with DDPE.

Superficial temporal artery injury and delayed post-cranioplasty infection

OBJECTIVE

Complications after cranioplasty after decompressive craniectomy (DC) have been reported to be as high as 40%. The superficial temporal artery (STA) is at substantial risk for injury in standard reverse question-mark incisions that are typically used for unilateral DC. The authors hypothesize that STA injury during craniectomy predisposes patients to post-cranioplasty surgical site infection (SSI) and/or wound complication.

METHODS

A retrospective study of all patients at a single institution who underwent cranioplasty after decompressive craniectomy and who underwent imaging of the head (computed tomography angiogram, magnetic resonance imaging with intravenous contrast, or diagnostic cerebral angiography) for any indication between the two procedures was undertaken. The degree of STA injury was classified and univariate statistics were used to compare groups.

RESULTS

Fifty-four patients met inclusion criteria. Thirty-three patients (61%) had evidence of complete or partial STA injury on pre-cranioplasty imaging. Nine patients (16.7%) developed either an SSI or wound complication after cranioplasty and, among these, four (7.4%) experienced delayed (>2 weeks from cranioplasty) complications. Seven of 9 patients required surgical debridement and cranioplasty explant. There was a stepwise but non-significant increase in post-cranioplasty SSI (STA present: 10%, STA partial injury: 17%, STA complete injury: 24%, P=0.53) and delayed post-cranioplasty SSI (STA present: 0%, STA partial injury: 8%, STA complete injury: 14%, P=0.26).

CONCLUSIONS

There is a notable but statistically non-significant trend toward increased rates of SSI in patients with complete or partial STA injury during craniectomy.

Time of Discharge and 30-Day Re-Presentation to an Acute Care Setting After Elective Lumbar Decompression Surgery

BACKGROUND

Evidence regarding the consequence of efforts to increase patient throughput and decrease length of stay in the context of elective spine surgery is limited.

OBJECTIVE

To evaluate whether early time of discharge results in increased rates of hospital readmission or return to emergency department for patients admitted after elective, posterior, lumbar decompression surgery.

METHODS

We conducted a retrospective cohort study of 779 patients admitted to hospital after undergoing elective, posterior, lumbar decompression surgery. Multiple logistic regression evaluated the relationship between time of discharge and the primary outcome of return to acute care within 30 days, while controlling for sociodemographic, procedural, and discharge characteristics.

RESULTS

In multiple logistic regression, time of discharge earlier in the day was not associated with increased odds of return to acute care within 30 days (odds ratio [OR] 1.18, 95% CI 0.92-1.52, P = .19). Weekend discharge (OR 1.99, 95% CI 1.04-3.79, P = .04) increased the likelihood of return to acute care. Surgeon experience (<1 year of attending practice, OR 0.43, 95% CI 0.19-1.00, P = .05 and 2-5 years of attending practice, OR 0.50, 95% CI 0.25-1.01, P = .054), weekend discharge (OR 0.49, 95% CI 0.27-0.89, P = .02), and physical therapy evaluation (OR 0.20, 95% CI 0.12-0.33, P < .001) decreased the likelihood of discharge before noon.

CONCLUSION

Time of discharge is not associated with risk of readmission or presentation to the emergency department after elective lumbar decompression. Weekend discharge is independently associated with increased risk of readmission and decreased likelihood of prenoon discharge.

Thalamic neuromodulation in epilepsy: A primer for emerging circuit-based therapies

INTRODUCTION

Epilepsy is a common, often debilitating disease of hyperexcitable neural networks. While medically intractable cases may benefit from surgery, there may be no single, well-localized focus for resection or ablation. In such cases, approaching the disease from a network-based perspective may be beneficial.

AREAS COVERED

Herein, the authors provide a narrative review of normal thalamic anatomy and physiology and propose general strategies for preventing and/or aborting seizures by modulating this structure. Additionally, they make specific recommendations for targeting the thalamus within different contexts, motivated by a more detailed discussion of its distinct nuclei and their respective connectivity. By describing important principles governing thalamic function and its involvement in seizure networks, the authors aim to provide a primer for those now entering this fast-growing field of thalamic neuromodulation for epilepsy.

EXPERT OPINION

The thalamus is critically involved with the function of many cortical and subcortical areas, suggesting it may serve as a compelling node for preventing or aborting seizures, and so it has increasingly been targeted for the surgical treatment of epilepsy. As various thalamic neuromodulation strategies for seizure control are developed, there is a need to ground such interventions in a mechanistic, circuit-based framework.

Development of posttraumatic frontal brain abscess in association with an orbital roof fracture and odontogenic abscess: A case report

Background:

Brain abscess is a potentially fatal condition. Orbital fractures caused by penetrating injury may be associated with intracranial infection. Such complication associated with blunt trauma, orbital roof fractures, and odontogenic abscesses is exceedingly rare.

Case Description:

We report the case of a 40-year-old transgender female with a frontal abscess presenting several weeks following a motor vehicle crash from which she suffered multiple facial fractures and an odontogenic abscess. On computed tomography scan, the patient had multiple right-sided facial fractures, including a medial orbital wall fracture and a right sphenoid fracture extending into the superior orbital roof. There was hemorrhage notable in the right frontal lobe. Communication with the ethmoid sinuses likely provided a conduit for bacterial spread through the orbit and into the intracranial and subdural spaces.

Conclusion:

Skull base fractures that communicate with a sinus, whether it be frontal, ethmoid, or sphenoid may increase the risk of brain abscess, especially in patients who develop an odontogenic abscess. Surgical repair of the defect is essential, and treating patients prophylactically with antibiotics may be beneficial.

Pedicle Screw Placement Using Intraoperative Computed Tomography and Computer-Aided Spinal Navigation Improves Screw Accuracy and Avoids Postoperative Revisions: Single-Center Analysis of 1400 Pedicle Screws

OBJECTIVE

Intraoperative computed tomography and navigation (iCT-Nav) is increasingly used to aid spinal instrumentation. We aimed to document the accuracy and revision rate of pedicle screw placement across many screws placed using iCT-Nav. We also assess patient-level factors predictive of high-grade pedicle breach.

METHODS

Medical records of patients who underwent iCT-Nav pedicle screw placement between 2015 and 2017 at a single center were retrospectively reviewed. Screw placement accuracy was individually assessed for each screw using the 2-mm incremental grading system for pedicle breach. Predictors of high-grade (>2 mm) breach were identified using multiple logistic regression.

RESULTS

In total, 1400 pedicle screws were placed in 208 patients undergoing cervicothoracic (29; 13.9%), thoracic (30; 14.4), thoracolumbar (19; 9.1%) and lumbar (130; 62.5%) surgeries. iCT-Nav afforded high-accuracy screw placement, with 1356 of 1400 screws (96.9%) being placed accurately. In total, 37 pedicle screws (2.64%) were revised intraoperatively during the index surgery across 31 patients, with no subsequent returns to the operating room because of screw malpositioning. After correcting for potential confounders, males were less likely to have a high-grade breach (odds ratio [OR] 0.21; 95% confidence interval [CI] 0.10-0.59, P = 0.003) whereas lateral (OR 6.21; 95% CI 2.47-15.52, P < 0.001) or anterior (OR 5.79; 95% CI2.11-15.88, P = 0.001) breach location were predictive of a high-grade breach.

CONCLUSIONS

iCT-Nav with postinstrumentation intraoperative imaging is associated with a reduced need for costly postoperative return to the operating room for screw revision. In comparison with studies of navigation without iCT where 1.5%-1.7% of patients returned for a second surgery, we report 0 revision surgeries due to screw malpositioning.

Toward more accurate documentation in neurosurgical care

OBJECTIVE

Accurate clinical documentation is foundational to any quality improvement endeavor as it is ultimately the medical record that is measured in assessing change. Literature on high-yield interventions to improve the accuracy and completeness of clinical documentation by neurosurgical providers is limited. Therefore, the authors sought to share a single-institution experience of a two-part intervention to enhance clinical documentation by a neurosurgery inpatient service.

METHODS

At an urban, level I trauma, academic teaching hospital, a two-part intervention was implemented to enhance the accuracy of clinical documentation of neurosurgery inpatients by residents and advanced practice providers (APPs). Residents and APPs were instructed on the most common neurosurgical complications or comorbidities (CCs) and major complications or comorbidities (MCCs), as defined by Medicare. Additionally, a "system-based" progress note template was changed to a "problem-based" progress note template. Prepost analysis was performed to compare the CC/MCC capture rates for the 12 months prior to the intervention with those for the 3 months after the intervention.

RESULTS

The CC/MCC capture rate for the neurosurgery service line rose from 62% in the 12 months preintervention to 74% in the 3 months after intervention, representing a significant change (p = 0.00002).

CONCLUSIONS

Existing clinical documentation habits by neurosurgical residents and APPs may fail to capture the extent of neurosurgical inpatients with CC/MCCs. An intervention that focuses on the most common CC/MCCs and utilizes a problem-based progress note template may lead to more accurate appraisals of neurosurgical patient acuity.

Short- and long-term opioid use in survivors of subarachnoid hemorrhage

OBJECTIVES

Opioids are frequently used for analgesia in patients with acute subarachnoid hemorrhage (SAH) due to a high prevalence of headache and neck pain. However, it is unclear if this practice may pose a risk for opioid dependence, as long-term opioid use in this population remains unknown. We sought to determine the prevalence of opioid use in SAH survivors, and to identify potential risk factors for opioid utilization.

METHODS

We analyzed a cohort of consecutive patients admitted with non-traumatic and suspected aneurysmal SAH to an academic referral center. We included patients who survived hospitalization and excluded those who were not opioid-naïve. Potential risk factors for opioid prescription at discharge, 3 and 12 months post-discharge were assessed.

RESULTS

Of 240 SAH patients who met our inclusion criteria (mean age 58.4 years [SD 14.8], 58% women), 233 (97%) received opioids during hospitalization and 152 (63%) received opioid prescription at discharge. Twenty-eight patients (12%) still continued to use opioids at 3 months post-discharge, and 13 patients (6%) at 12-month follow up. Although patients with poor Hunt and Hess grades (odds ratio 0.19, 95% CI 0.06-0.57) and those with intraventricular hemorrhage (odds ratio 0.38, 95% CI 0.18-0.87) were less likely to receive opioid prescriptions at discharge, we did not find significant differences between patients who had long-term opioid use and those who did not.

CONCLUSION

Opioids are regularly used in both the acute SAH setting and immediately after discharge. A considerable number of patients also continue to use opioids in the long-term. Opioid-sparing pain control strategies should be explored in the future.

Demand for Essential Nonambulatory Neurosurgical Care Decreased While Acuity of Care Increased During the Coronavirus Disease 2019 (COVID-19) Surge

Background

In times of health resource reallocation, capacities must remain able to meet a continued demand for essential, nonambulatory neurosurgical acute care. This study sought to characterize the demand for and provision of neurosurgical acute care during the coronavirus disease 2019 (COVID-19) pandemic.

Methods

This single-center cross-sectional observational analysis compared nonambulatory neurosurgical consult encounters during the peri-surge period (March 9 to May 31, 2020) with those during an analogous period in 2019. Outcomes included consult volume, distribution of problem types, disease severity, and rate of acute operative intervention.

Results

A total of 1494 neurosurgical consults were analyzed. Amidst the pandemic surge, 583 consults were seen, which was 6.4 standard deviations below the mean among analogous 2016–2019 periods (mean 873; standard deviation 45, P = 0.001). Between 2019 and 2020, the proportion of degenerative spine consults decreased in favor of spinal trauma (25.6% vs. 34% and 51.9% vs. 41.4%, P = 0.088). Among aneurysmal subarachnoid hemorrhage cases, poor-grade (Hunt and Hess grades 4–5) presentations were more common (30% vs. 14.8%, P = 0.086). A greater proportion of pandemic era consults resulted in acute operative management, with an unchanged absolute frequency of acutely operative consults (123/583 [21.1%] vs. 120/911 [13.2%], P < 0.001).

Conclusions

Neurosurgical consult volume during the pandemic surge hit a 5-year institutional low. Amidst vast reallocation of health care resources, demand for high-acuity nonambulatory neurosurgical care continued and proportionally increased for greater-acuity pathologies. In our continued current pandemic as well as any future situations of mass health resource reallocation, neurosurgical acute care capacities must be preserved.

A minimally invasive lateral approach with CT navigation for open biopsy and diagnosis of Nocardia nova L4–5 discitis osteomyelitis: illustrative case

BACKGROUND

Lumbar spine osteomyelitis can be refractory to conventional techniques for identifying a causal organism. In cases in which a protracted antibiotic regimen is indicated, obtaining a conclusive yield on biopsy is particularly important. Although lateral transpsoas approaches and intraoperative computed tomography (CT) navigation are well documented as techniques used for spinal arthrodesis, their utility in vertebral biopsy has yet to be reported in any capacity.

OBSERVATIONS

In a 44-year-old male patient with a history of Nocardia bacteremia, CT-guided biopsy failed to confirm the microbiology of an L4–5 discitis osteomyelitis. The patient underwent a minimally invasive open biopsy in which a lateral approach with intraoperative guidance was used to access the infected disc space retroperitoneally. A thin film was obtained and cultured Nocardia nova, and the patient was treated accordingly with a long course of trimethoprim-sulfamethoxazole.

LESSONS

The combination of a lateral transpsoas approach with intraoperative navigation is a valuable technique for obtaining positive yield in cases of discitis osteomyelitis of the lumbar spine refractory to CT-guided biopsy.