Toward Generalizable Trajectory Planning for Human Intracerebral Trials and Therapy.

INTRODUCTION: Stereotactic neurosurgical techniques are increasingly used to deliver biologics, such as cells and viruses, although standardized procedures are necessary to ensure consistency and reproducibility. OBJECTIVE: We provide an instructional guide to help plan for complex image-guided trajectories; this may be of particular benefit to surgeons new to biologic trials and companies planning such trials. METHODS: We show how nuclei can be segmented and multiple trajectories with multiple injection points can be created through a single or multiple burr hole(s) based on preoperative images. Screenshots similar to those shown in this article can be used for planning purposes and for quality control in clinical trials. RESULTS: This method enables the precise definition of 3-D target structures, such as the putamen, and efficient planning trajectories for biologic injections. The technique is generalizable and largely independent of procedural format, and thus can be integrated with frame-based or frameless platforms to streamline reproducible therapeutic delivery. CONCLUSIONS: We describe an easy-to-use and generalizable protocol for intracerebral trajectory planning for stereotactic delivery of biologics. Although we highlight intracerebral stem cell delivery to the putamen using a frame-based stereotactic delivery system, similar strategies may be employed for different brain nuclei using different platforms. We anticipate this will inform future advanced and fully automated neurosurgical procedures to help unify the field and decrease inherent variability seen with manual trajectory planning.

Sixth Nerve Palsy Secondary to Traumatic Carotid-Jugular Fistula.

Carotid-jugular fistulae are rare complications of penetrating head and neck trauma. We report an unusual case of an external carotid-internal jugular fistula presenting with diplopia due to sixth nerve paresis. A 38-year-old Caucasian female presented in the setting of acute neurovascular neck trauma and weeks later developed symptomatic diplopia. An acquired carotid-internal jugular fistula affecting the abducens nerve secondarily via compression from a distended inferior petrosal sinus was diagnosed and treated using endovascular coil embolisation, resolving the patient's symptoms. A posteriorly draining external carotid artery-internal jugular venous fistula can be an uncommon cause of a compressive sixth cranial nerve palsy.

Newer treatment paradigm improves outcomes in the most common neurosurgical disease of the elderly: a literature review of middle meningeal artery embolization for chronic subdural hematoma.

Chronic subdural hematoma (cSDH) is one of the most prevalent neurosurgical diseases, especially in the elderly. Yet, its incidence is predicted to increase further, paralleling the growth of the geriatric population. While surgical evacuation is technically straightforward, it is associated with significant morbidity and mortality. In fact, 30% of patients are expected to have hematoma recurrence and to need repeat surgical evacuation, and 20% of patients are expected to lose independence and require long-term care. A pathophysiology more complex than originally presumed explains the disappointing results observed for decades. At its core, the formation of microcapillaries and anastomotic channels with the middle meningeal artery (MMA) perpetuates a constant cycle resulting in persistence of hematoma. The rationale behind MMA embolization is simple: to stop cSDH at its source. Over the last few years, this "newer" option has been heavily studied. It has shown tremendous potential in decreasing hematoma recurrence and improving neurological outcomes. Whether combined with surgical evacuation or performed as the only treatment, the scientific evidence to its benefits is unequivocal. Here, we aimed to review cSDH in the elderly and discuss its more recent treatment options with an emphasis on MMA embolization.

Carotid artery dissection and non-aneurysmal subarachnoid hemorrhage following carotid endarterectomy.

Stroke continues to be a major public health issue resulting in high mortality and severe long-term disability. Carotid endarterectomy (CEA) plays an important role in the prevention of ischemic stroke. Complications associated with CEA can be life threatening and prompt recognition is crucial. In this report, we present a patient who presented to the hospital with progressive headache, 2 weeks following CEA. He was neurologically intact and hypertensive. Non-contrast head computed tomography (CT) scan showed convexity subarachnoid hemorrhage (SAH). He was found to have a left internal carotid artery dissection. Patients who present to the hospital following CEA with headache and hypertension benefit from a non-contrast head CT scan. The presence of SAH can be a warning sign of cerebral hyperperfusion syndrome. Carotid artery dissection is also a disease entity that can occur in the post-operative period. Prompt recognition and treatment is crucial for the management of these disease entities.

Pipeline Embolization Device (PED) and Flow Re-Direction Endoluminal Device (FRED) for Intracranial Aneurysms; A Comparative Systematic Review and Meta-Analysis Study.

BACKGROUND: When it comes to intracranial aneurysms, the quest for more effective treatments is ongoing. Flow diversion represents a growing advancement in this field. This review seeks to compare two variants of the endovascular flow diversion method: the Flow Re-Direction Endoluminal Device (FRED) and the Pipeline Embolization Device (PED). METHODS: A systematic review was conducted according to the PRISMA guideline using PubMed, Scopus, Web of Science, and Embase, using appropriate terms to compare PED and FRED in double-arm studies from conception until October 8th, 2023. RESULTS: The meta-analysis encompassed 1,769 patients, with a predominance of females (75.5%), among whom 973 patients underwent FRED procedures, while 651 received PED interventions. At six months, complete occlusion rates were 0.62 for FRED and 0.68 for PED (P = 0.68). At one year and the last follow-up, no significant differences were observed between FRED and PED, respectively. Adequate occlusion rates were similar between FRED and PED (0.82 vs 0.79, P = 0.68). FRED showed a statistically significant higher rate of good mRS scores at follow-up (1.00 vs. 0.97, P = 0.03). Hemorrhage and re-treatment rates were higher in PED (P < 0.01) without considering the rupture status of the aneurysms due to the lack of data. CONCLUSION: This meta-analysis suggests comparable efficacy but different safety profiles between FRED and PED in treating intracranial aneurysms. FRED demonstrated a higher rate of good mRS scores, while PED showed increased hemorrhage and re-treatment rates. Understanding these differences is crucial for informed decision-making in clinical practice.

Altered endocannabinoid metabolism compromises the brain-CSF barrier and exacerbates chronic deficits after traumatic brain injury in mice.

Endocannabinoids [2-arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine (AEA)], endogenously produced arachidonate-based lipids, are anti-inflammatory physiological ligands for two known cannabinoid receptors, CB1 and CB2, yet the molecular and cellular mechanisms underlying their effects after brain injury are poorly defined. In the present study, we hypothesize that traumatic brain injury (TBI)-induced loss of endocannabinoids exaggerates neurovascular injury, compromises brain-cerebrospinal fluid (CSF) barriers (BCB) and causes behavioral dysfunction. Preliminary analysis in human CSF and plasma indicates changes in endocannabinoid levels. This encouraged us to investigate the levels of endocannabinoid-metabolizing enzymes in a mouse model of controlled cortical impact (CCI). Reductions in endocannabinoid (2-AG and AEA) levels in plasma were supported by higher expression of their respective metabolizing enzymes, monoacylglycerol lipase (MAGL), fatty acid amide hydrolase (FAAH), and cyclooxygenase 2 (Cox-2) in the post-TBI mouse brain. Following increased metabolism of endocannabinoids post-TBI, we observed increased expression of CB2, non-cannabinoid receptor Transient receptor potential vanilloid-1 (TRPV1), aquaporin 4 (AQP4), ionized calcium binding adaptor molecule 1 (IBA1), glial fibrillary acidic protein (GFAP), and acute reduction in cerebral blood flow (CBF). The BCB and pericontusional cortex showed altered endocannabinoid expressions and reduction in ventricular volume. Finally, loss of motor functions and induced anxiety behaviors were observed in these TBI mice. Taken together, our findings suggest endocannabinoids and their metabolizing enzymes play an important role in the brain and BCB integrity and highlight the need for more extensive studies on these mechanisms.

Concomitant central venous sinus thrombosis and subdural hematoma in acute promyelocytic leukemia: middle meningeal artery embolization enables safe anticoagulation. Illustrative case.

BACKGROUND: Acute promyelocytic leukemia (APL) has long been associated with coagulation disorders. The proposed mechanism is a combination of fibrinolysis, proteolysis, platelet dysfunction, thrombocytopenia, and possibly disseminated intravascular coagulation. Hemorrhagic complications are prominent. OBSERVATIONS: In this case, a 25-year-old female with newly diagnosed APL developed extensive cerebral venous thrombosis (CVT) and was initiated on a protocol with idarubicin and all-trans retinoic acid. The general recommendation for treating CVT is anticoagulation to stabilize the existing thrombus and prevent propagation. The patient was initiated on a heparin drip, but her clinical course was complicated by subdural hemorrhage (SDH) and epidural hemorrhage in the setting of thrombocytopenia. Anticoagulation was held, and her CVT propagated on follow-up imaging. To restart anticoagulation for CVT with a limited risk of SDH, the authors pursued middle meningeal artery (MMA) embolization. The patient was transitioned to apixaban and discharged to home. LESSONS: MMA embolization enables safe anticoagulation in patients with concomitant CVT and SDH. The authors report the complex clinical course and effective management of this rare clinical scenario.

Dural Sandwich Technique for Hemicraniectomy and Benefits During Cranioplasty.

OBJECTIVE: Hemicraniectomy is a commonly performed neurosurgical procedure used in the setting of medically refractory malignant intracranial hypertension. Complications from cranioplasty after hemicraniectomy can be significant, including infection and wound issues. Difficulty with scar tissue during exposure for cranioplasty can be challenging and can lead to prolonged surgical time and increased bleeding. We describe a surgical technique, termed the "dural sandwich," that could provide a significant benefit during cranioplasty as compared with traditional single-layered dural closure. METHODS: A retrospective analysis was conducted that included 14 patients who underwent a hemicraniectomy procedure over a 4-year period. Seven patients were identified who received a cranioplasty after dural sandwich technique during craniectomy. They were compared with a similar patient group of 7 patients who received a cranioplasty after conventional hemicraniectomy with single-layered dural closure. Surgical time, estimated blood loss, and complication rates were compared between the 2 groups. Analysis of variance measures were performed to assess for statistically significant differences in blood loss and operative time between the dural sandwich and control groups. Statistical significance was defined as P < 0.05. RESULTS: The mean estimated blood loss was 82.1 mL in the dural sandwich craniectomy group versus 150 mL in the conventional hemicraniectomy group (P < 0.05). The mean estimated surgical time was 91.7 minutes in the dural sandwich craniectomy group versus 127.5 minutes in the conventional craniectomy group (P < 0.05). There was no evidence of neurologic deterioration, cerebral spinal fluid leak, or postoperative hematoma requiring evacuation in either group. In the conventional craniectomy group, a single report of a wound infection was noted that was treated conservatively with antibiotics. CONCLUSIONS: By layering bovine pericardium above and below the dura during initial hemicraniectomy, an artificial plane is created that improves ease of exposure during cranioplasty. This technique could reduce surgical time and blood loss during subsequent cranioplasty, and potentially reduce recovery time and postoperative complications.

A Retrospective Cohort Analysis of Hemorrhagic Arteriovenous Malformations Treated with Combined Endovascular Embolization and Gamma Knife Stereotactic Radiosurgery.

BACKGROUND: The management of brain arteriovenous malformations (AVMs) remains a controversial topic. Given the relatively low incidence, high heterogeneity, and high morbidity and mortality of these lesions, consensus on treatment strategies is an issue of concern to organized neurosurgery. The present retrospective analysis examined and quantified the outcomes of patients with an initial presentation of intracranial hemorrhage from a Spetzler-Martin grade III or IV AVM, later ruled out as surgical candidates. METHODS: A total of 16 patients (5 females; 11 males) had presented with symptomatic hemorrhage confirmed by non-contrast-enhanced computed tomography and were deemed to not be surgical candidates owing to AVM location and/or architecture. The patients underwent combined endovascular embolization and gamma knife stereotactic radiosurgery (SRS). The modified Rankin scale was used to measure the clinical outcomes, comparing the scores at presentation, gamma knife treatment, and the last known follow-up examination. A radiographic evaluation was used to determine the level of AVM nidus involution after the procedure. RESULTS: The present study identified 16 patients with ruptured high-grade AVMs of high surgical risk. All the patients had undergone immediate embolization with delayed SRS for treatment of the hemorrhage and nidus of the AVM. A statistically significant proportion of patients showed marked improvement in the modified Rankin scale scores. No subsequent repeat hemorrhage or any associated complications after embolization occurred in any patient. CONCLUSION: These findings warrant consideration of endovascular embolization with adjuvant SRS as a powerful treatment option for cases with high surgical morbidity due to AVM characteristics.

Clinically Silent Adrenocorticotropic Hormone-Positive Crooke Cell Adenoma: Case Report and Review of Literature.

BACKGROUND: Pituitary adenomas are one of the most common tumors of adulthood; however, subtypes such as Crooke cell adenoma are relatively rare. CASE DESCRIPTION: We present the case of a 55-year-old woman who presented with new-onset intermittent headache and dizziness. Clinical and laboratory investigations were not suggestive of corticotroph tumor. However, subsequent computed tomography and magnetic resonance imaging scans revealed the presence of a suprasellar pituitary adenoma displacing the optic chiasma superiorly, with hemorrhage and sellar expansion. The lesion was removed by transsphenoidal surgery and the biopsy confirmed the lesion to be a nonfunctioning pituitary macroadenoma. Further investigation revealed that the specimen demonstrated Crooke hyaline changes, with strong immunoreactivity for adrenocorticotropic hormone. However, initial workup and postoperative testing lacked evidence of Cushing disease. There was no sign of recurrence after 1-year follow-up. CONCLUSIONS: Clinically silent Crooke cell adenomas are rare occurrences, and as such we report this case with investigation of past cases.

Medieval neurosurgery: contributions from the Middle East, Spain, and Persia.

Modern neurological and spinal surgical techniques have been developed on the foundations established by predecessors. Modern 21st century neurosurgery begins in the Babylonian period, with the Edwin Smith papyrus. Throughout history, periods of enlightenment have resulted in advances in knowledge and understanding that have served as stepping stones for generations to come. As in other fields, in neurosurgery these periods of "enlightenment" have occurred in a variety of civilizations and time periods.

Evolution of the treatment of cerebral vasospasm.

Cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is a disease process for which the lack of effective treatments has plagued neurosurgeons for decades. Historically, successful treatment after SAH in the acute setting was often followed by a rapid, uncontrollable deterioration in the subacute interval. Little was known regarding the nature and progression of this condition until the mid-1800s, when the disease was first described by Gull. Insight into the origin and natural history of cerebral vasospasm came slowly over the next 100 years, until the 1950s. Over the past five decades our understanding of cerebral vasospasm has expanded exponentially. This newly discovered information has been used by neurosurgeons worldwide for successful treatment of complications associated with vasospasm. Nevertheless, although great strides have been made toward elucidating the causes of cerebral vasospasm, a lasting cure continues to elude experts and the disease continues to wreak havoc on patients after aneurysmal SAH.

Golf-associated head injury in the pediatric population: a common sports injury.

OBJECT: Golf-related injuries constitute a common type of sports injury in the pediatric population. The increase in the frequency of these injuries is largely attributed to the increase in the popularity of golf and greater use of golf carts by children. METHODS: The purpose of this study was to investigate the mechanisms and complications associated with golf-related injuries in the pediatric population and, by doing so, assist in the prevention of such injuries. We reviewed the charts of 2546 pediatric patients evaluated by the neurosurgery service at the authors' institution over a 6-year period. There were 64 cases of sports-related injuries. Of these, 15 (23%) were golf-related, making these injuries the second-largest group of sports-related injuries. Depressed skull fracture was the most common injury observed. Neurosurgical intervention was required in 33% of the cases. With rare exceptions, patients made good recoveries during a mean follow-up period of 22.2 months. One death occurred due to uncontrollable cerebral edema following a golf cart accident. One child required shunt placement and several revisions following an injury sustained from a golf ball. CONCLUSIONS: Children should be advised on the proper use of golf equipment as a preventive measure to avoid these injuries. Precautionary guidelines and safety training guidelines should be established. The institution of a legal minimum age required to operate a golf cart should be considered.

History of infection control and its contributions to the development and success of brain tumor operations.

Before advancements in infection control, only conditions that brought patients near death warranted the risk of surgical intervention. If patients survived the operation, infection was nearly inevitable and death by overwhelming sepsis was knocking at their door. In the late 19th century, with the development of germ theory by Louis Pasteur and its subsequent application to surgical sterility by Joseph Lister, surgeons were able to operate with a substantially reduced risk of infection. Consequently, surgeons became more confident and began to explore more extravagant procedures, including elective operations within the cranial vault. As scientific knowledge expanded in the 20th century, so did the advancement of infection control with the use of prophylactic antibiotic drugs, heat sterilization of instruments, and microbial barriers. Recent reports have placed the rate of complications due to infection between 0.75 and 2.32% for intracranial operations.

History of posterior thoracic instrumentation.

The term "backbone" appears in many expressions used in modern day society. In any scenario, it has one central meaning: stability. Best defined as a foundation that is able to sustain multiple stressors without adversely affecting integrity, the commonly and appropriately termed backbone of humans is the spinal column. As the central focus of stability in our species, the spine is subject to a great degree of trauma and mechanical forces. A variety of methods have been developed throughout history in the treatment of spinal column injury. Initial treatment involved the use of simple traction devices for the reduction of spinal fractures; these have evolved to include the current insertion of spinal instrumentation. The authors review the historical treatment and development of posterior instrumentation for thoracic spinal injury.

Treatment of atlantoaxial instability in pediatric patients.

The atlantoaxial region has been extensively described as a spinal segment especially prone to injury in children. In this clinical review, the authors evaluate and summarize the management of 23 pediatric cases of atlantoaxial instability treated between March 1990 and October 2002. Four broad categories of atlantoaxial problems were observed-atlantoaxial rotatory subluxation in six patients, anterior-posterior atlantoaxial instability caused by ligamentous injury or congenital ligamentous laxity (10 patients), atlantoaxial fracture with or without dislocation (five patients), and atlantooccipital dislocation (two patients). Most cases (60.9%) were treated without surgical intervention, resulting in excellent outcomes; however, 21.7% of cases were treated with a cervical halo (mean patient age 72.6 months) alone for 3 months. Various techniques of surgical stabilization including transarticular screws with sublaminar wiring, transoral decompression with posterior plating, and laminectomy with Steinmann pin occipital-cervical fusion were used with good results. Both patients with atlantooccipital dislocation underwent immediate Locksley occipital-cervical fusion, with marked neurological improvement. Individualized case management must be based on clinical presentation, with internal fixation being the last resort.

Open surgical management of a ruptured intracranial aneurysm in Klippel-Trenaunay-Weber (KTW) syndrome.

A 24-year-old man with a history of Klippel-Trenaunay-Weber syndrome presented with severe headache and neck pain. Work-up revealed subarachnoid hemorrhage and evidence of multiple intracranial aneurysms. The patient was treated with open surgical clipping of his ruptured aneurysm and is currently doing well.