Occipital-interhemispheric transtentorial pineal mass resection.

The occipital approach for pineal tumors was first described by James Poppen in 1966. Since then, it has been widely used for accessing deep-seated tumors as it offers a wider surgical view than the supracerebellar transtentorial approach. This video demonstrates the technical nuances of the occipital transtentorial approach and the exoscopic dissection of a pineal gland tumor in a 66-year-old male. Use of the exoscope over the microscope provides certain ergonomic advantages and improves surgical workflow, as demonstrated here. The video can be found here: https://stream.cadmore.media/r10.3171/2023.10.FOCVID23161.

Real-time vessel segmentation and reconstruction for virtual fixtures for an active handheld microneurosurgical instrument.

PURPOSE: Complications related to vascular damage such as intra-operative bleeding may be avoided during neurosurgical procedures such as petroclival meningioma surgery. To address this and improve the patient's safety, we designed a real-time blood vessel avoidance strategy that enables operation on deformable tissue during petroclival meningioma surgery using Micron, a handheld surgical robotic tool. METHODS: We integrated real-time intra-operative blood vessel segmentation of brain vasculature using deep learning, with a 3D reconstruction algorithm to obtain the vessel point cloud in real time. We then implemented a virtual-fixture-based strategy that prevented Micron's tooltip from entering a forbidden region around the vessel, thus avoiding damage to it. RESULTS: We achieved a median Dice similarity coefficient of 0.97, 0.86, 0.87 and 0.77 on datasets of phantom blood vessels, petrosal vein, internal carotid artery and superficial vessels, respectively. We conducted trials with deformable clay vessel phantoms, keeping the forbidden region 400 [Formula: see text]m outside and 400 [Formula: see text]m inside the vessel. Micron's tip entered the forbidden region with a median penetration of just 8.84 [Formula: see text]m and 9.63 [Formula: see text]m, compared to 148.74 [Formula: see text]m and 117.17 [Formula: see text]m without our strategy, for the former and latter trials, respectively. CONCLUSION: Real-time control of Micron was achieved at 33.3 fps. We achieved improvements in real-time segmentation of brain vasculature from intra-operative images and showed that our approach works even on non-stationary vessel phantoms. The results suggest that by enabling precise, real-time control, we are one step closer to using Micron in real neurosurgical procedures.

A Rare Third Ventricular Dermoid Cyst in an Adult With Imaging Characteristics Consistent With a Colloid Cyst.

A 64-year-old male presented with spontaneous intracerebral hemorrhage and obstructive hydrocephalus without evidence of a third ventricular mass in 2019. The patient was lost to follow-up and re-admitted one year later for hydrocephalus secondary to a third ventricular mass. Imaging characteristics were consistent with a colloid cyst, which was the presumptive diagnosis. A transcallosal transchoroidal approach was utilized for cyst resection. The cyst wall was carefully incised, releasing flakey, partially solid contents which were grossly inconsistent with a colloid cyst. Due to the concern of iatrogenic cyst rupture in the setting of unknown diagnosis, the patient was placed on steroids post-operatively. Surgical specimens sent at the time of surgery were consistent with dermoid cyst. We present the first reported case of a third ventricular dermoid cyst in an adult initially misdiagnosed as a colloid cyst based on imaging characteristics.

Single Fraction Frameless Stereotactic Radiosurgery on the Gamma Knife Icon for Patients With Brain Metastases: Time to Abandon the Frame?

PURPOSE: The latest version of the Gamma Knife, the Icon, allows for immobilization with a mask in lieu of the traditional frame during stereotactic radiosurgery. There have been some concerns regarding extent of immobilization during single fraction frameless treatment and potential effect on outcomes. As such, we reviewed outcomes in patients with brain metastases treated in a single fraction using either a frame or mask on the Gamma Knife Icon at our institution. METHODS AND MATERIALS: We reviewed the records of 95 patients with a total of 374 metastases treated between May 2019 and January 2021. Thirty-nine patients (41%) were treated using the Leksell frame with the remainder being immobilized with a mask. The median number of metastatic lesions was 2 (1-20). The median prescription dose was 20 Gy (11.5-24 Gy). Odds ratios were generated to identify predictors of mask use. Kaplan-Meier analysis was used to calculate survival, local failure, and distant failure rates. Cox regression was used to identify predictors of survival. Propensity matching was used to account for indication bias. RESULTS: Of the 95 patients treated, 88 (93%) had follow-up with a median duration of 5 months (1-18). Frame utilization was more likely with 6 to 10 brain metastases. Median overall survival was not reached and was 70% and 60% at 6 and 12 months for the entire cohort, respectively. There was no significant difference in survival by immobilization method (P = .12). Six patients had local failure in 10 total lesions (3 patients in each group). After propensity matching the 12 month tumor local control was 96% and 85% for framed and frameless cases, respectively (P = .07). CONCLUSIONS: Frameless mask-based stereotactic radiosurgery using the Gamma Knife Icon is feasible and maintains the excellent local control seen with the use of the headframe.

Medicine and surgery residents' perspectives on the impact of COVID-19 on graduate medical education.

The COVID-19 crisis has had an unprecedented impact on resident education and well-being: social distancing guidelines have limited patient volumes and forced virtual learning, while personal protective equipment (PPE) shortages, school/daycare closures, and visa restrictions have served as additional stressors. Our study aimed to analyze the effects of COVID-19 crisis-related stressors on residents' professional and personal lives. In April 2020, we administered a survey to residents at a large academic hospital system in order to assess the impact of the pandemic on residency training after >6 weeks of a modified schedule. The primary outcome was to determine which factors or resident characteristics were related to stress during the pandemic. Our secondary goals were to examine which resident characteristics were related to survey responses. Data were analyzed with regression analyses. Ninety-six of 205 residents completed the survey (47% response rate). For our primary outcome, anxiety about PPE (P < 0.001), female gender (P = 0.03), and the interaction between female gender and anxiety about PPE (P = 0.04) were significantly related to increased stress during the COVID-19 pandemic. Secondary analyses suggested that medicine residents were more comfortable than surgical residents using telemedicine (P > 0.001). Additionally, compared to juniors, seniors believed that the pandemic was more disruptive, modified schedules were effective, and virtual meetings were less effective while virtual lectures were more effective (all P ≤ 0.05) Furthermore, the pandemic experience has allowed seniors in particular to feel more confident to lead in future health crises (P ≤ 0.05). Medicine and surgery residency programs should be cognizant of and closely monitor the effects of COVID-19 crisis-related factors on residents' stress and anxiety levels. Transparent communication, telemedicine, online lectures/meetings, procedure simulations, advocacy groups, and wellness resources may help to mitigate some of the challenges posed by the pandemic.

An anatomical study of the foramen of Monro: implications in management of pineal tumors presenting with hydrocephalus.

BACKGROUND: For pineal tumors presenting with hydrocephalus, simultaneous endoscopic third ventriculostomy (ETV) and tumor biopsy is commonly used as the initial step in management. To analyze the restriction which the foramen of Monro poses to this procedure, one must start with a detailed description of the microsurgical anatomy of the foramen in living subjects. However, the orientation and shape of the foramen of Monro make this description difficult with conventional imaging techniques. METHOD: Virtual reality technology was applied on MRIs on living subject without hydrocephalus, as well as patients with hydrocephalus, to generate precise anatomical models with sub-millimeter accuracy. The morphometry of the foramen of Monro was studied in each group. In addition, displacement of the margins of the foramen was studied in detail for simultaneous ETV and pineal tumor biopsy through a single burr hole. RESULTS: In 30 normal subjects, the foramen of Monro had oval-shaped openings averaging 5.23 mm2. The foramen was larger in people above age 55 (p = 0.007) and on the left side compared to the right (p = 0.002). For patients with clinical presentation of hydrocephalus, the average opening was 32.6 mm2. Simulated single burr hole simultaneous ETV and pineal tumor biopsy was performed in 10 specimens. Average displacement of the posterior and anterior margins of the foramen was 5.71 mm and 5.76 mm, respectively. However, maximum displacement reached 9.3 mm posteriorly and 10 mm anteriorly. CONCLUSIONS: The foramen of Monro is an oval-shaped cylinder that changes in size and orientation in the hydrocephalic patient. If universally applied to all patients regardless of foramen and tumor size, ETV/biopsy can displace structures around the Foramen of Monro up to 1 cm, which can potentially lead to neurological damage. Careful pre-operative assessment is critical to determine if a single burr hole approach is safe.

Iron Oxide Nanoparticles with Grafted Polymeric Analogue of Dimethyl Sulfoxide as Potential Magnetic Resonance Imaging Contrast Agents.

Novel water-dispersible hybrid iron oxide nanoparticles grafted with a polymeric analogue of dimethyl sulfoxide (DMSO) were prepared. Superparamagnetic iron oxide nanoparticles with immobilized atom-transfer radical polymerization (ATRP) initiators were prepared via an in situ method using 12-(2-bromoisobutyramido)dodecanoic acid as a surface ligand/initiator. The initiator-functionalized particles were employed in a surface-initiated initiator for continuous activator regeneration ATRP to graft poly(2-(methylsulfinyl)ethyl acrylate) (a polyacrylate analogue of DMSO) from the surface. The resulting hybrid nanoparticles showed a high magnetic relaxivity ratio ( r2/ r1) of 600 at 7 T in fetal bovine serum, and a good biocompatibility up to 1000 mg L-1.

Spontaneous intraventricular rupture of a craniopharyngioma cyst: A case report.

Intraventricular rupture of craniopharyngioma cysts is an unusual event which is associated with a high risk of loculated or communicating hydrocephalus. A 75-year-old woman presented at the Emergency Department of our hospital with mental status deterioration due to chemical ventriculitis and acute hydrocephalus following the intraventricular rupture of a craniopharyngioma cyst. The patient was treated with stress-dose steroid therapy. In addition, she underwent placement of an external ventricular drain and endoscopy-assisted intra-cystic placement of an Ommaya reservoir for the aspiration of the cystic fluid. The patient's condition improved; she was shunted in an expeditious fashion and discharged from the Intensive Care Unit within 2 weeks of her admission with the reservoir in place for the continued drainage of the cyst.

Case Report of a Primary Pituitary Abscess and Systematic Literature Review of Pituitary Abscess with a Focus on Patient Outcomes.

BACKGROUND: Pituitary abscess is a rare but potentially life-threatening condition with an incidence of 0.2%-1.1% of operative pituitary lesions. Diagnosis can be challenging, because this disorder shares many similarities with other pituitary lesions in terms of signs and symptoms and radiographic findings. Most pituitary abscesses are categorized as secondary, arising from preexisting pituitary lesions or in conjunction with transsphenoidal surgery, sepsis, meningitis, or sinusitis. There have been only a few reports of primary pituitary abscess, which occurs without any of the aforementioned risk factors. CASE DESCRIPTION: We present a case of primary pituitary abscess in a 38-year-old woman with headaches, blurry vision, polyuria, and polydipsia who was found to have hypopituitarism. Brain magnetic resonance imaging showed a sellar/suprasellar mass, which was endoscopically resected via a transsphenoidal approach. Egress of yellow-greenish creamy fluid was noted on dural incision. The patient was treated with a 6-week course of antibiotic therapy postoperatively and had resolution of symptoms. CONCLUSIONS: A PubMed search was performed; all cases of pituitary abscess reported in the literature were screened, and 200 cases including our case were analyzed with a focus on outcomes. The most common presentations were headache, visual disturbance, and endocrine abnormalities. Approximately 66.1% of patients achieved partial or complete recovery of pituitary function; 75.7% with vision deficits recovered visual function. Treatment via a craniotomy had a recurrence rate of 17.2% compared with 9.7% via a transsphenoidal approach. To our knowledge, this is the first systematic review on the topic and the largest series reported.

Use of the Swiveling Technique for Endoscopic Removal of a Colloid Cyst of the Third Ventricle: A Technical Note.

Colloid cysts are considered benign brain tumors and usually occur in the anterior third ventricle. The clinical presentation may be nonspecific and heterogeneous including headaches, visual changes, nausea, and vomiting. The symptomatology is frequently associated with the development of hydrocephalus. Neuroendoscopic removal is increasingly replacing open microsurgical approaches as the standard of care for the treatment of symptomatic colloid cysts of the third ventricle. We describe the case of a 42-year-old man who was found to have a colloid cyst of the third ventricle while undergoing evaluation for a dural arteriovenous fistula. We highlight the rotational, or "swiveling," method for extraction of the colloid cyst.

Endoscopic Third Ventriculostomy in 250 Adults With Hydrocephalus: Patient Selection, Outcomes, and Complications.

BACKGROUND: Endoscopic third ventriculostomy (ETV) has been used predominantly in the pediatric population in the past. Application in the adult population has been less extensive, even in large neurosurgical centers. To our knowledge, this report is one of the largest adult ETV series reported and has the consistency of being performed at 1 center. OBJECTIVE: To determine the efficacy, safety, and outcome of ETV in a large adult hydrocephalus patient series at a single neurosurgical center. In addition, to analyze patient selection criteria and clinical subgroups (including those with ventriculoperitoneal shunt [VPS] malfunction or obstruction and neurointensive care unit patients with extended ventricular drainage before ETV) to optimize surgical results in the future. METHODS: We conducted a retrospective review of adult ETV procedures performed at our center between 2000 and 2014. RESULTS: The overall rate of success (no further cerebrospinal fluid diversion procedure performed plus clinical improvement) of 243 completed ETVs was 72.8%. Following is the number of procedures with the success rate in parentheses: aqueduct stenosis, 56 (91%); communicating hydrocephalus including normal pressure hydrocephalus, nonnormal pressure hydrocephalus, and remote head trauma, 57 (43.8%); communicating hydrocephalus in postoperative posterior fossa tumor without residual tumor, 14 (85.7%); communicating hydrocephalus in subarachnoid hemorrhage without intraventricular hemorrhage, 23 (69.6%); obstruction from tumor/cyst, 42 (85.7%); VPS obstruction (diagnosis unknown), 23 (65.2%); intraventricular hemorrhage, 20 (90%); and miscellaneous (obstructive), 8 (50%). There were 9 complications in 250 intended procedures (3.6%); 5 (2%) were serious. CONCLUSION: Use of ETV in adult hydrocephalus has broad application with a low complication rate and reasonably good efficacy in selected patients.

The Impact of Preoperative Angiographic Identification of the Artery of Adamkiewicz on Surgical Decision Making in Patients Undergoing Thoracolumbar Corpectomy.

STUDY DESIGN: Retrospective study. OBJECTIVE: To investigate the impact of spinal angiography on selection of surgical side in patients undergoing thoracolumbar corpectomy. SUMMARY OF BACKGROUND DATA: The artery of Adamkiewicz provides the major blood supply to the thoracolumbar spinal cord. Its location makes it vulnerable to injury during surgical procedures. Preoperative diagnostic spinal angiography is often used to determine the level and lateralization of the artery. METHODS: Data were gathered regarding level and laterality of the Adamkiewicz artery in 34 patients who underwent lateral extracavitary approaches to the thoracolumbar spine, preceded by diagnostic spinal angiography for localization of that artery. Two experienced spine surgeons were retrospectively polled regarding ideal side of approach for each case. This was compared with the actual side that was selected after angiographic localization. RESULTS: The artery was successfully identified in 71% of patients. The artery was most commonly located on the left side (83%) between T9 and L1 (83%). Diagnostic angiography seemed to have influenced surgical decision making in 54% of cases. In 21% of patients, there was no need to alter the side of approach. In the remaining 25%, the surgical plan was not altered on the basis of angiographic data, presumably due to anatomic limitations. No angiography- or surgery-related complications occurred in any of the patients. CONCLUSION: Preoperative spinal angiography seems to impact surgical decision making with regard to alteration of the side of approach in patients undergoing thoracolumbar corpectomy via lateral extracavitary approaches. LEVEL OF EVIDENCE: 4.

Combined use of covered stent and flow diversion to seal iatrogenic carotid injury with vessel preservation during transsphenoidal endoscopic resection of clival tumor.

BACKGROUND: Transsphenoidal tumor resection can lead to internal carotid artery (ICA) injury. Vascular disruption is often treated with emergent vessel deconstruction, incurring complications in a subset of patients with poor collateral circulation and resulting in minor and major ischemic strokes. METHODS: We attempted a novel approach combining a covered stent graft (Jostent) and two flow diverter stents [Pipeline embolization devices (PEDs)] to treat active extravasation from a disrupted right ICA that was the result of a transsphenoidal surgery complication. This disruption occurred during clival tumor surgery and required immediate sphenoidal sinus packing. Emergent angiography revealed continued petrous carotid artery extravasation, warranting emergent vessel repair or deconstruction for treatment. To preserve the vessel, we utilized a covered Jostent. Due to tortuosity and lack of optimal wall apposition, there was reduced, yet persistent extravasation from an endoleak after Jostent deployment that failed to resolve despite multiple angioplasties. Therefore, we used PEDs to divert the flow. RESULTS: Flow diversion relieved the extravasation. The patient remained neurologically intact post-procedure. CONCLUSIONS: This case demonstrates successful combined use of a covered stent and flow diverters to treat acute vascular injury resulting from transsphenoidal surgery. However, concerns remain, including the requirement of dual antiplatelet agents increasing postoperative bleeding risks, stent-related thromboembolic events, and delayed in-stent restenosis rates.

Prospective review of a single center's general pediatric neurosurgical intraoperative and postoperative complication rates.

OBJECT: The authors conducted a study to compare the complication rate (CR) of pediatric neurosurgical procedures in a general neurosurgery department to the CRs that are reported in the literature and to establish a baseline of CR for further targeted improvement of quality neurosurgical care. METHODS: The authors analyzed the prospectively collected data from a complication registration of 1000 consecutive pediatric neurosurgical procedures in 581 patients from the beginning of the registration in January 2004 through August 2008. A pediatric neurosurgeon was involved in 50.5% of the procedures. All adverse events (AEs) from induction of anesthesia until 30 days postoperatively were recorded. RESULTS: Overall, 229 complications were counted in 202 procedures. The overall CR was 20.2%, with a 2.7% intraoperative CR and a 17.5% postoperative CR. Tumor surgery was associated with the highest CR (32.7%), followed by CSF disorders (21.8%). The mortality rate was 0.3%. An unplanned return to the operating room in relation to an AE happened in 10.5% of all procedures and in 52% of procedures associated with AEs, the majority of which were related to CSF disorders. CONCLUSIONS: The CR in pediatric neurosurgical procedures was significant, and more than half of the patients with an AE required a repeat surgical procedure. Analysis of CRs should be a prerequisite for the prevention of complications and for the development of targeted interventions to reduce the CR (for example, infection rates).

Spontaneous involution of a Rathke's cleft cyst in a patient with normal cortisol secretion.

BACKGROUND: Rathke's cleft cyst (RCC) is a lesion derived from maldeveloped remnants of a dorsal invagination of the stomodeal ectoderm (Rathke's pouch). Although commonly found on autopsy, these lesions rarely become symptomatic during an individual's lifetime. When symptoms occur, they most often include headaches, visual disturbances, and/or varying degrees of hypopituitarism. The natural history remains unclear. The current standard of care includes surgical drainage and biopsy of the cyst wall or surgical resection of symptomatic lesions; however, debate exists regarding the management of asymptomatic lesions. Rare reports of spontaneously resolving RCC can be found in the literature. CASE DESCRIPTION: We describe the management of a case of RCC in an 8½-year-old girl who presented with a history of growth deceleration since 4 years of age and near-growth arrest since 7 years of age. Her parents also described a tendency towards polydipsia since she was 2 years of age. Endocrine evaluation revealed growth hormone deficiency, central hypothyroidism, and diabetes insipidus, but normal cortisol secretion. The patient experienced no symptoms characteristic of intracranial or sellar mass. Neurologic examination was normal; formal ophthalmologic examination revealed no deficits. The magnetic resonance imaging (MRI) was consistent with RCC. The patient was treated medically for her hormone deficiencies. Over the next year, her sellar mass spontaneously involuted. Twenty-seven months after her initial presentation to our clinic, imaging revealed no sellar mass; the patient remained on hormone replacement therapy. CONCLUSION: Although the natural history of RCC requires further study, observation with serial MRI may be an acceptable management strategy in the absence of debilitating symptoms.

An episode of severely suppressed electrocerebral activity recorded by electroencephalography during endoscopic resection of a colloid cyst.

Intraoperative neuromonitoring utilizing electroencephalography (EEG) is rarely performed during neuroendoscopy. The authors present a case in which this monitoring modality was used for a patient with a colloid cyst in preparation for an open craniotomy should an endoscopic approach fail. In this case, EEG serendipitously captured near-complete cessation of electrocerebral activity that occurred during intraventricular irrigation in response to ventricular collapse and resulted in no postoperative deficits. To the authors' knowledge, this is the first reported case of severe suppression of electrical activity captured by EEG during neuroendoscopy. Although they describe a transient phenomenon that resulted in no residual cognitive or neurological deficits, the importance of cautious introduction of ventricular irrigation, the need to carefully monitor intracranial pressure during neuroendoscopic procedures, and the need to pay close attention to irrigation temperature and composition should not be underestimated. Additional studies regarding the utility of EEG in alerting neurosurgeons to adverse electrical cerebral activity during neuroendoscopy are warranted.

Enlarged thalamostriate vein causing unilateral Monro foramen obstruction. Case report.

Causes of unilateral hydrocephalus resulting from an obstruction at the Monro foramen include foraminal atresia, tumors, gliosis, contralateral shunting, and infectious and inflammatory conditions. However, few reports in the literature cite vascular lesions as the cause of the obstruction. To their knowledge, the authors present the first report of unilateral hydrocephalus occurring due to an abnormally enlarged thalamostriate vein independent of an arteriovenous malformation or developmental venous angioma. The condition was treated successfully by endoscopic septum pellucidum fenestration. A 28-year-old man was referred for evaluation due to a 10-year history of chronic headaches that worsened in severity over the past year. A CT scan of the head revealed unilateral right ventricular dilation. Cranial MR imaging with and without contrast administration showed a dilated right thalamostriate-internal vein complex without any evidence of associated arteriovenous malformation or venous angioma. Endoscopic exploration of the right lateral ventricle showed an enlarged subependymal thalamostriate vein obstructing the Monro foramen. An endoscopic fenestration of the septum pellucidum was performed, resulting in alleviation of the patient's symptoms. Abnormally enlarged venous structures may cause obstructive unilateral hydrocephalus and can be a rare cause of chronic, intermittent headaches in adults. Endoscopic fenestration of the septum pellucidum is an effective treatment.

Antimicrobial suture wound closure for cerebrospinal fluid shunt surgery: a prospective, double-blinded, randomized controlled trial.

OBJECT: Implantation of cerebrospinal fluid (CSF) shunting devices is associated with a 5-15% risk of infection as cited in contemporary pediatric neurosurgical literature. Shunt infections typically require complete removal of the device and prolonged antibiotic treatment followed by shunt replacement. Moreover, shunt infections are commonly associated with prolonged hospital stays, potential comorbidity, and the increased risk of neurological compromise due to ventriculitis or surgical complications. The authors prospectively evaluated the incidence of CSF shunt infection following shunt procedures performed using either antimicrobial suture (AMS) or conventional suture. METHODS: In a single-center, prospective, double-blinded, randomized controlled trial, the authors enrolled 61 patients, among whom 84 CSF shunt procedures were performed over 21 months. Randomization to the study (AMS) or control (placebo) group was stratified to minimize the effect of known shunt infection risk factors on the findings. Antibacterial shunt components were not used. The primary outcome measure was the incidence of shunt infection within 6 months of surgery. RESULTS: The shunt infection rate in the study group was 2 (4.3%) of 46 procedures and 8 (21%) of 38 procedures in the control group (p = 0.038). There were no statistically significant differences in shunt infection risk factors between the groups (procedure type and time, age < 6 months, weight < 4 kg, recent history of shunt infection). No suture-related adverse events were reported in either group. CONCLUSIONS: These results support the suggestion that the use of AMS for CSF shunt surgery wound closure is safe, effective, and may be associated with a reduced risk of postoperative shunt infection. A larger randomized controlled trial is needed to confirm this association.