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The neurosurgical management of spinal neoplasms has undergone immense development in parallel with advancements made in general spine surgery. Laminectomies were performed as the first surgical procedures used to treat spinal neoplasms. Since then, neurosurgical spinal oncology has started to incorporate techniques that have developed from recent advances in minimally invasive spine surgery. Neurosurgery has also integrated radiotherapy into the treatment of spine tumors. In this historical vignette, we present a vast timeline spanning from the Byzantine period to the current day and recount the major advancements in the management of spinal neoplasms.

BACKGROUND Gangliogliomas are well-differentiated, slow-growing glioneuronal neoplasms frequently reported to harbor upregulating alterations in the mitogen-activated protein kinase pathway, particularly serine–threonine protein kinase B-RAF alterations. Fusions involving neurotrophin tyrosine receptor kinase (NTRK) genes have rarely been reported in ganglioglioma. Similarly, echinoderm microtubule-associated protein-like (EML) 4 gene fusion has been described in lung cancer, but none has been reported in ganglioglioma. OBSERVATIONS This report discusses the care of a 72-year-old man presenting with medication-refractory, left-sided focal seizures who was found to have a nongadolinium-enhancing, T2-hyperintense, right frontoparietal lesion. The patient received resection, and histological analysis found a World Health Organization grade I ganglioglioma, with genetic analysis demonstrating an EML4-NTRK3 gene fusion protein. LESSONS To our knowledge, this is the first report of an NTRK3 fusion, EML4-NTRK3, in an adult ganglioglioma, which is otherwise mostly associated with BRAF alterations and activation of the mitogen-activated protein kinase signaling pathway. Further studies are needed to elucidate the function of the resultant fusion protein and determine whether it may serve as a future therapeutic target.

Background Significant intra- and inter-heterogeneity exists in gliomas. This provides clinical, radiological, diagnostic, and treatment challenges. To date, there have been few efforts to comprehensively catalog information obtained in the operating room that spatially links neuro-navigation localization to imaging characteristics, gross intraoperative visual findings, and pathological/molecular features. The value of this spatial localization is probably greatest in high grade gliomas, which have been demonstrated to have intra-tumoral histological and genetic/epigenetic heterogeneity. METHODS An IRB-approved institutional registry of patients undergoing clinically-indicated surgery with use of an image-guidance system (IGS) was launched in November 2019 and as of June 1, 2022 includes nearly 500 patients, of which 243 were diagnosed with gliomas. Intraoperatively, locations within the gross tumor or tumor-infiltrated brain were sampled at each surgeon’s discretion, and each sample was linked to their precise location with the IGS system (“geo-tagged”). The registry includes information regarding surgeon; anesthesia technique; use of intraoperative tumor fluorescence; tumor location and volume; pathologic diagnosis and molecular features, and sample number. RESULTS Of 243 gliomas, 26 were low grade and 217 were high grade with 174 being glioblastoma. For enhancing tumors, volume of enhancement ranged from 0.31 to 127.0 cm3 with an average of 22.9 cm3. Tumors were widely distributed throughout the cerebrum with 133 left-sided tumors, 110 right-sided and 32 spanning multiple lobes or deep subcortical structures including the brainstem. 51% of surgeries were under awake anesthesia, and 40% were performed using fluorescence guidance. The average number of navigation image-linked samples collected per tumor was 3.67; 3.48 in low grade gliomas, and 3.69 in high grade gliomas. Samples are archived in frozen and/or formalin-fixed, paraffin-embedded formats for future research. CONCLUSION This registry provides the foundation for correlation of imaging, intraoperative findings, and pathology in brain tumors, and it will support detailed laboratory/translational investigations addressing tumor heterogeneity.

Frequency and duration of outpatient clinic follow-up for patients with shunted hydrocephalus varies among clinicians and assessment of follow-up regimens is lacking. The aim of this study is to investigate whether routine clinic visits alter care and whether they identify patients requiring shunt revision surgery, as well as, to better understand how patients utilize the outpatient clinic and present for shunt revision evaluation. This is a single-centered retrospective study of 154 patients requiring shunt revision surgery from 2009 to 2018 who had at least one prior clinic evaluation. The median age for shunt placement and revision were 3 months and 11 years old, respectively. Routine clinic visits led to a change in care for 16 patients (10.4%); including additional imaging, follow-up, or a combination of the two. With regards to revision surgery, days from prior shunt surgery, Chiari II/myelomeningocele pathology, and shunt type (p 0.01) did affect time to presentation. Four patients (2.6%) requiring revision surgery were identified at routine clinic follow-up, while 92 (59.7%) and 47 (30.5%) presented to the emergency department and clinic sick visit, respectively. Presentation to clinic resulted in a statistically significant decrease in shunt revision surgery length-of-stay compared to presentation to the emergency department or inpatient admission for another condition. Even with increased emergency room utilization, increased clinic connectivity, and improved patient education, routine clinic visits remain an important component in the follow-up of patients with shunted hydrocephalus by helping to guide clinical care and identify patients requiring shunt revision surgery.

Ketamine, a phencyclidine analog and dissociative anesthetic, has been used in anesthesia since the 1960s. Serial subanesthetic administration has been explored for treatment of depression and chronic pain; however, there has been a recent surge in its intraoperative and perioperative use among anesthesia providers. As ketamine becomes an important addition to multimodal acute pain regimens, it important that anesthesia providers review the physiologic underpinnings of ketamine administration. Herein, we review the primary scientific literature and discuss recent studies that have implicated ketamine in inflammation and oxidative stress, inhibition of ion channels in dorsal horn neurons, and in disruption of frontoparietal communication. Also discussed are the potential clinical implications these effects may have for patients.

Background Direct penetrating trauma to the spinal cord as a result of stabbing is rare. The vertebral column is strongly suited to protecting the vital neural structures underneath, especially in the midline. Case Description A 25-year-old woman experienced a direct stabbing injury to her spinal cord, through the midline structures, resulting in bilateral dorsal column injury. She remained intact with regard to motor function despite bilateral sensory and proprioception loss. Conclusions Owing to the strength of the protective elements of the osseous structures surrounding the spinal cord, direct stabbing injuries usually result in incomplete neurologic deficits. This is generally manifested as a Brown-Sequard syndrome because of the midline ligamentous structures and spinous processes deflecting injuries laterally. Our patient experienced a direct midline puncture, resulting in a unique case of bilateral dorsal column injury. These injuries are generally treated conservatively, in the absence of a retained foreign body. Spinal cord stabbing injuries are a rare entity with interesting clinical and anatomic correlations.

Postherpetic neuralgia (PHN) after acute herpes zoster ophthalmicus involves unilateral pain persisting or recurring for at least 3 months in the distribution of one or more branches of the trigeminal nerve. Patients often describe the pain associated with PHN as a deep aching or burning, dysesthetic, hyperesthetic, or electric shock-like sensation. The incidence of PHN increases with age and varies from 7 to 27%, depending on age group. 1 A subset of these patients develops medication-refractory PHN and should be referred for neurosurgical evaluation. Motor cortex stimulation (MCS) and trigeminal nucleus caudalis dorsal root entry zone (NC DREZ) lesioning are two therapies that may provide substantial relief to patients suffering from medication-refractory, postherpetic neuropathic facial pain.

Vertebral metastases often lead to a complex pain syndrome that consists of both nociceptive and neuropathic pain. Multimodal medical management often includes paracetamol, non-steroidal anti-inflammatory agents, bisphosphonates, opioids, antidepressants, anti-epileptics, and neuroleptics. Surgical treatment to address oncologic burden and spinal instability, radiation therapy, and vertebroplasty or kyphoplasty may be indicated for some patients. However, often times patients with advanced malignancies are not able to safely undergo surgery and have medication-refractory oncologic pain. For these patients and for patients unwilling to undergo large oncologic or spinal stabilization surgeries, intrathecal drug therapy (IDT) serves as a safe and effective adjunct in the management of cancer-related pain.

Background Helicopter transport may shorten transport time to neurosurgical intervention; however, there are few data regarding its utility for nontraumatic emergencies. Methods Prehospital and hospital records of all patients transferred via helicopter to Dartmouth-Hitchcock Medical Center for spontaneous subarachnoid hemorrhage between January 2007 and December 2011 were reviewed. Primary outcome measure was emergent tertiary-level care intervention, defined as ventriculostomy, conventional angiography, endovascular treatment, or craniotomy within 3 hours of arrival. Results Fifty-one patients met inclusion criteria. Median helicopter transport time, defined as time from telephone referral to arrival, was 97 minutes (range, 61–214 minutes). Fifteen patients underwent intervention within 3 hours of arrival (29%), 19 patients underwent intervention between 3 and 6 hours (37%), 9 patients underwent intervention between 6 to 12 hours (18%), and 11 patients underwent intervention greater than 12 hours after arrival (16%). Univariate analysis of pretransfer clinical and radiographic findings showed significant correlations between Glasgow Coma Scale (GCS) score less than 15 (odds ratio [OR], 22.8; 95% confidence interval [CI], 4.2–122.5), World Federation of Neurologic Surgeons (WFNS) scale greater than 2 (OR, 46.75; 95% CI, 7.511–290.99), presence of intraparenchymal hemorrhage (OR, 4.7; 95% CI, 1.3–17.5), and intubation (OR, 12.4; 95% CI, 2.9–51.8) with emergent intervention. On logistic multivariate regression analysis, GCS score less than 15 and WFNS scale score greater than 2 independently predicted emergent intervention. Conclusions A majority of patients with spontaneous subarachnoid hemorrhage who were transferred by interfacility helicopter ambulance did not require emergent intervention. GCS score less than 15 at an outside hospital was independently associated with emergent intervention on multivariate analysis.

Hypothalamic hamartomas are benign tumors known to cause gelastic or dacrystic seizures, precocious puberty, developmental delay, and medically refractory epilepsy. These tumors are most often sporadic but rarely can be associated with Pallister-Hall syndrome, an autosomal dominant familial syndrome caused by truncation of glioblastoma transcription factor 3, a downstream effector in the sonic hedgehog pathway. In this clinical report, the authors describe two brothers with a different familial syndrome. To the best of the authors’ knowledge, this is the first report in the literature describing a familial syndrome caused by germline mutations in the Smoothened (SMO) gene and the first familial syndrome associated with hypothalamic hamartomas other than Pallister-Hall syndrome. The authors discuss the endoscopic endonasal biopsy and subtotal resection of a large hypothalamic hamartoma in one of the patients as well as the histopathological findings encountered. Integral to this discussion is the understanding of the hedgehog pathway; therefore, the underpinnings of this pathway and its clinical associations to date are also reviewed.

Currently, treatment of brain tumors is limited to resection, chemotherapy, and radiotherapy. Thermal ablation has been recently explored. High-intensity focused ultrasound (HIFU) is being explored as an alternative. Specifically, the authors propose delivering HIFU internally to the tumor with an MRI-guided robotic assistant (MRgRA). The advantage of the authors’ interstitial device over external MRI-guided HIFU (MRgHIFU) is that it allows for conformal, precise ablation and concurrent tissue sampling. The authors describe their workflow for MRgRA HIFU delivery.

Background: Because of the commonality of diagnostic magnetic resonance imaging (MRI), MRI conditional technology has increased throughout the device industry. It is often difficult to be aware of MRI specifications for each device. Objectives: We provide a review of the clinical experience with MRI and spinal cord stimulation (SCS) devices and develop a general reference of current device/MRI specifications. Methods: We reviewed the available literature on the clinical experience with SCS devices and examined its specifications. Results: We developed a user-friendly table of the specific compatibility of SCS devices in the USA and the European Union, and examined the existing literature on the clinical experience with MRI and SCS devices. We share our experience with obtaining spine MRI with MRI conditional SCS leads. Conclusion: By describing SCS device specifications and reviewing the literature, we provide a guide to implanting and treating physicians on obtaining MRIs in patients who have SCS devices.

Early neurosurgical procedures dealt mainly with treatment of head trauma, especially skull fractures. Since the early medical writings by Hippocrates, a great deal of respect was given to the dura mater, and many other surgeons warned against violating the dura. It was not until the 19th century that neurosurgeons started venturing beneath the dura, deep into the brain parenchyma. With this advancement, brain retraction became an essential component of intracranial surgery. Over the years brain retractors have been created pragmatically to provide better visualization, increased articulations and degrees of freedom, greater stability, less brain retraction injury, and less user effort. Brain retractors have evolved from simple handheld retractors to intricate brain-retraction systems with hand-rest stabilizers. This paper will focus on the history of brain retractors, the different types of retractors, and the progression from one form to another.