Exploring optimal microscopic keyhole access to the skull base: an anatomical evaluation of transciliary supraorbital and transpalpebral orbitofrontal craniotomy approaches.

PURPOSE: The past two decades have witnessed the rise of keyhole microscopic minimally invasive surgeries, including the transciliary supraorbital approach (TCA) and transpalpebral approach (TPA), commonly known as the transorbital approach. This study aims to elucidate the nuances, specific indications, and advantages of each approach. METHODS: A series of dissections were conducted on five formalin-fixed, alcohol-preserved cadaver heads. The TCA was performed on one side, and the TPA on the other. Virtual measurements of working angles for both approaches were recorded. Additionally, three clinical cases were presented to illustrate the practical application of the techniques. RESULTS: For TCA, the craniotomy dimensions were 1.7 cm x 2.5 cm (Cranial-Caudal (CC) x Lateral-Lateral (LL)), while for TPA, they measured 2.1 cm x 2.9 cm (CC x LL). The measurements of anterior clinoid processes (ACP) were obtained and compared between approaches. In the TCA, the mean ipsilateral ACP measurement was 62 mm (Range: 61 -63 mm), and the mean contralateral ACP measurement was 71.2 mm (Range: 70 -72 mm). In TPA, these measurements were 47.8 mm (Range: 47 -49 mm) and 62.8 mm (Range: 62 -64 mm), respectively. TCA exhibited an average cranial-caudal angle of 14.9°, while TPA demonstrated an average of 8.3°. CONCLUSION: The anterior cranial fossa was better exposed by a TCA, which also featured shorter operative times, enhanced midline visualization, and a quicker learning curve. Conversely, the middle fossa was better exposed by a TPA, making it an excellent option for middle fossa pathologies, including those in the anterior temporal lobe. After sphenoid bone wing drilling, the TPA offers superior visualization from the lateral to the medial aspect and enhances the CC angle. Additionally, the TPA reduces the risk of postoperative frontalis palsy based on anatomic landmarks. However, the TPA requires a greater cranial osteotomy, and due to unfamiliarity with eyelid anatomy, the learning curve for most neurosurgeons is lengthier for this procedure.

Thrombosis in Cushing's disease; raising the flag of concern.

Cushing's disease (CD) is associated with an increased risk of venous thromboembolic events. The purpose of this review is to discuss preventive strategies for post-operative thrombosis in CD patients and their impact on patient outcomes. A systematic review under PRISMA guidelines was conducted within PubMed, Embase, Web of Science, and Cochrane databases through July 2022. Of the 3207 papers retrieved, seven articles were included in this systematic review. Four hundred forty-eight patients were presented in the reviewed studies and the overall reported mortality was 2.67% (12/448). Three studies utilized prophylaxis methods including graduated compression stockings (GCS) and early ambulation (EA) while the remaining four studies only used anticoagulation medicine. Only 20 patients received pre-operative prophylactic treatment, while 366 patients received post-operative prophylaxis which was delivered either immediately after surgery or at different time intervals within 2 days following the surgery. Thrombotic events mainly occurred within two to 3 months after surgery. Overall, a higher frequency of thromboembolic events and mortality was observed in the control groups in comparison to groups receiving prophylaxis. A combination of anticoagulation, EA, and GCS might reduce thrombotic events and mortality in CD patients after treatment. Although the early commencement of a prophylactic anticoagulation regimen on the same day of surgery and continuing up to 3 months seems beneficial, the application of a prophylactic regimen should be utilized with caution since the number of included studies was insufficient to draw a strong conclusion, as well as neither prospective study nor randomized controlled trials existed.

Safety of craniotomy for brain tumor resection in octogenarians and older patients - a matched - cohort analysis.

INTRODUCTION: The incidence of brain tumors has increased in elderly population overtime. Their eligibility to a major surgery remains a questionable subject. This study evaluated prognostic factors and 30-days morbidity and mortality in octogenarian population who underwent craniotomy for resection of brain tumor. MATERIALS AND METHODS: A total of 154 patients were divided into two different groups: patients above 80 years old and patients below 65 years old. In both groups, patients were stratified based on diagnosis with benign tumors [meningioma] and malignant tumors [high-grade gliomas and metastases]. Multivariable logistic regression model with backward elimination method was utilized to identify the independent risk factors for 30-days readmission and post-operative complications. RESULTS: The analysis revealed no significant difference in 30-day readmission (p = 0.7329), 30-day mortality (0.6854) or in post-operative complication (p = 0.3291) between age ≥ 80 and age ≤ 65 groups. A longer length of stay (LOS) was observed in the older patients (p = 0.0479). There was a significant difference in the pre-post KPS between the two groups (p < 0.0001). ASA (p = 0.0315) and KPS (p = 0.071) were found as important prognostic factors associated with post-operative mortality in both groups. CONCLUSION: Octogenarians can withstand craniotomy without any significant increase in 30-day readmission, 30-day mortality and post-operative complications as compared to patients younger than age 65. The ASA score (>3) and/or KPS (<70) were the most important prognostic factors for 30-days readmission and mortality.

3D preoperative planning in the ER with OsiriX®: when there is no time for neuronavigation.

The evaluation of patients in the emergency room department (ER) through more accurate imaging methods such as computed tomography (CT) has revolutionized their assistance in the early 80s. However, despite technical improvements seen during the last decade, surgical planning in the ER has not followed the development of image acquisition methods. The authors present their experience with DICOM image processing as a navigation method in the ER. The authors present 18 patients treated in the Emergency Department of the Hospital das Clínicas of the University of Sao Paulo. All patients were submitted to volumetric CT. We present patients with epidural hematomas, acute/subacute subdural hematomas and contusional hematomas. Using a specific program to analyze images in DICOM format (OsiriX(®)), the authors performed the appropriate surgical planning. The use of 3D surgical planning made it possible to perform procedures more accurately and less invasively, enabling better postoperative outcomes. All sorts of neurosurgical emergency pathologies can be treated appropriately with no waste of time. The three-dimensional processing of images in the preoperative evaluation is easy and possible even within the emergency care. It should be used as a tool to reduce the surgical trauma and it may dispense methods of navigation in many cases.

Debilitating trigeminal neuralgia secondary to idiopathic intracranial hypertension.

Idiopathic intracranial hypertension (IIH) is characterized by raised intracranial pressure with unknown etiology. The most common neurological manifestations are headache and visual loss. Often, other cranial nerve impairments are also found, most commonly in the VI nerve. Trigeminal neuralgia (TN) is a debilitating condition that is most frequently caused by neurovascular pathology, but TN secondary to IIH is a rare and poorly described topic. Possible explanations of TN in these patients include the distortion of the local anatomy at CN entry zones and fluid displacement causing distortion of the Meckel's cave. In the case below we describe the clinical course of an obese female patient with TN-like pain who underwent a ventriculoperitoneal shunt to treat IIH and experienced complete resolution of both conditions.

Trigeminal Neuralgia-Step-by-Step DYNA-Computed Tomography-Assisted Balloon Compression Rhizotomy.

Trigeminal nerve balloon compression (TNBC)1-3 can provide immediate therapeutic relief to patients suffering from trigeminal neuralgia. This is a particularly effective treatment option for patients who are not eligible for surgical procedures (i.e., elderly patients or patients with multiple comorbidities) or for patients who have had an insufficient response to microvascular decompression. TNBC can also be used as a bridge treatment before stereotactic radiosurgery. Use of intraoperative computed tomography-like images using a C-arm system (DYNA-CT) imaging facilitates the TNBC procedure.4,5 Three-dimensional DYNA-CT imaging with needle guidance allows for precise needle advancement and insertion through the foramen ovale. DYNA-CT enables the direct visualization and avoidance of vascular structures such as the carotid or internal maxillary arteries and results in decreased procedure times and complications. The authors present a step-by-step video demonstrating the use of intraoperative DYNA-CT needle guidance for TNBC (Video 1). A Siemens Artis Zee Biplane system is used for the procedure. A comprehensive description of all elements of the procedure is provided including balloon preparation, needle trajectory planning, needle advancement, 3-dimensional confirmation of the needle's depth and path, balloon placement, balloon inflation, and balloon removal. Tips and optimal strategies are presented. Advantages of using DYNA-CT for needle guidance include the reduction of fluoroscopy dose and fluoroscopy time. The average dose area product during conventional percutaneous balloon compression in prior studies was 1137 mGycm2, with a mean fluoroscopic time of 62 seconds.6 In our experience, the mean fluoroscopy dose is 274 mGycm2 and the total fluoroscopic time is about 45 seconds. Furthermore, during the DYNA-CT acquisition, the neurointerventional team stays outside the room during the DYNA-CT, which reduces the cumulative radiation to the operator. DYNA-CT needle guidance facilitates precise advancement of the needle into the foramen ovale and positioning of the balloon in the Meckel cave during TNBC. It is a safe and feasible technique that allows for the visualization and avoidance of important structures such as the internal carotid artery or the internal maxillary artery, resulting in decreased procedure times and complications.

Enhanced recovery after surgery in patients with normal pressure hydrocephalus undergoing ventriculoperitoneal shunting procedures.

OBJECTIVE: Patients with idiopathic normal pressure hydrocephalus (iNPH) who undergo ventriculoperitoneal shunt (VPS) placement often belong to an older demographic, putting them at increased risk of postoperative delirium and related complications. Recent literature documenting the use of Enhanced Recovery After Surgery (ERAS) protocols in various disciplines of surgery has shown improved clinical outcomes, faster discharge, and lower readmission rates. Early return to a familiar environment (i.e., discharged home) is a well-known predictor of reduced postoperative delirium. However, ERAS protocols are uncommon in neurosurgery, especially intracranial procedures. We developed a novel ERAS protocol for patients with iNPH undergoing VPS placement to gain further insight regarding postoperative complications, specifically delirium. METHODS: We studied 40 patients with iNPH with indications for VPS. Seventeen patients were selected at random to undergo the ERAS protocol, and twenty-three patients underwent the standard VPS protocol. The ERAS protocol consisted of measures to reduce infection, manage pain, minimize invasiveness, confirm procedural success with imaging, and shorten the length of stay. Pre-operative American Society of Anesthesiologists (ASA) grade was collected for each patient to indicate baseline risk. Rates of readmission and postoperative complications, including delirium and infection, were collected at 48 h, 2 weeks, and 4 weeks postoperatively. RESULTS: There were no perioperative complications among the 40 patients. There was no postoperative delirium in any of the ERAS patients. Postoperative delirium was observed in 10 of 23 non-ERAS patients. There was no statistically significant difference between the ASA grade between the ERAS and non-ERAS groups. CONCLUSIONS: We described a novel ERAS protocol for patients with iNPH receiving VPS focusing on an early discharge. Our data suggest that ERAS protocols in VPS patients might reduce the incidence of delirium without increasing the risk of infection or other postoperative complications.

Chiari Malformation Type 1 and Semi-Sitting Position-A Suitable Alternative for Patients with High BMI.

OBJECTIVE: Chiari I malformation results from a mismatch between the posterior fossa bones and neural components. Management usually relies on surgical treatment. Despite being the most common assumed positioning, the prone position can be challenging in high body mass index (BMI) patients (>40 kg/m2). METHODS: Between February 2020 and September 2021, 4 consecutive patients with class III obesity underwent posterior fossa decompression. The authors describe nuances of the positioning and perioperative details. RESULTS: No perioperative complications were reported. These patients are at a lower risk of bleeding and increased intracranial pressure as a consequence of low intra-abdominal pressure and venous return. In this context, the semi-sitting position, with the aid of accurate monitoring for venous air embolism, seems to be an advantageous surgical position in this group of patients. CONCLUSIONS: We present our results and technical nuances on positioning high BMI patients for posterior fossa decompression using a semi-sitting position.

Bilateral subthalamic nucleus stimulation for generalized dystonia after bilateral pallidotomy.

BACKGROUND: Thalamotomies and pallidotomies were commonly performed before the deep brain stimulation (DBS) era. Although ablative procedures can lead to significant dystonia improvement, longer periods of analysis reveal disease progression and functional deterioration. Today, the same patients seek additional treatment possibilities. METHODS: Four patients with generalized dystonia who previously had undergone bilateral pallidotomy came to our service seeking additional treatment because of dystonic symptom progression. Bilateral subthalamic nucleus DBS (B-STN-DBS) was the treatment of choice. The patients were evaluated with the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and the Unified Dystonia Rating Scale (UDRS) before and 2 years after surgery. RESULTS: All patients showed significant functional improvement, averaging 65.3% in BFMDRS (P = .014) and 69.2% in UDRS (P = .025). CONCLUSIONS: These results suggest that B-STN-DBS may be an interesting treatment option for generalized dystonia, even for patients who have already undergone bilateral pallidotomy.

Neurogenic neuroprotection: clinical perspectives.

Neurogenic neuroprotection is a promising approach for treating patients with ischemic brain lesions. In rats, stimulation of the deep brain nuclei has been shown to reduce the volume of focal infarction. In this context, protection of neural tissue can be a rapid intervention that has a relatively long-lasting effect, making fastigial nucleus stimulation (FNS) a potentially valuable method for clinical application. Although the mechanisms of neuroprotection induced by FNS remain partially unclear, important data have been presented in the last two decades. A 1-h electrical FNS reduced, by 59%, infarctions triggered by permanent occlusion of the middle cerebral artery in Fisher rats. The acute effect of electrical FNS is likely mediated by a prolonged opening of potassium channels, and the sustained effect appears to be linked to inhibition of the apoptotic cascade. A better understanding of the neuronal circuitry underlying neurogenic neuroprotection may contribute to improving neurological outcomes in ischemic brain insults.

Minimally invasive nummular approach to a giant meningioma of the anterior fossa.

Background: Several approaches are described for giant meningiomas of the anterior skull base. Recently, endonasal endoscopic approaches have been described as a minimally invasive (MI) alternative. However, the extension of dissection of the nose cavity and the risks of CSF leak do not fit in the MI prerogatives. We present an operative video illustrating a MI transcortical approach through a nummular craniotomy for a giant meningioma of the anterior fossa. Case Description: We report an 83-year-old female patient. On neurological examination, she was drowsy and hemiparetic on the left side. MRI scan demonstrated a giant anterior fossa lesion (7.6 × 6.2 × 6 cm). An 1.5 diameter craniotomy was placed in the right frontal region after MRI 3D reconstruction analysis. The first step was to debulk the core of the tumor with the ultrasonic aspirator. An important aspect is that the surgeon needs to rotate its positions around the patient in a 360° fashion for a total resection. The final step was to inspect the surgical cavity with the endoscope to check for any remaining tumor. The patient was discharged home 1 day after the surgery with no new deficits. Conclusion: Giant meningiomas of the anterior fossa are a different entity. When they reach the cortical surface, the surgical approach can be different from the common skull base meningiomas. We demonstrate that a MI transcortical approach can be a safe alternative for giant meningiomas, especially for high-risk patients, as the elderly ones.

Presurgical Planning with Open-Source Horos Software for Superficial Brain Arteriovenous Malformations.

BACKGROUND: Surgical planning for treating brain arteriovenous malformations (bAVMs) is challenging because it entails visualizing 3-dimensional (3D) relationships between the nidus, its feeding and en passage arteries, and draining veins. Surgical experience in developing the capacity to mentally visualize pathological bAVM angioarchitecture could be complemented by this software, and thus potentially lower the steep learning curve for understanding complex bAVM angioarchitecture. We evaluated the clinical application of freely available online 3D reconstruction software in facilitating visualization of AVM angioarchitecture for presurgical planning. METHODS: Preoperative Digital Imaging and Communications in Medicine magnetic resonance imaging/magnetic resonance angiography images of 56 superficial bAVMs from 2013 to 2018 were processed using open-source software Horos. 3D rendered images were compared with the surgical view to evaluate software accuracy and determine its value as a preoperative tool. 3D reconstructed images were compared with intraoperative recordings. RESULTS: A useful image identifying both the main feeding artery and draining vein was achieved in 35 of 56 cases (62.5%). Reconstructions of small AVMs (nidus ≤2 cm) and those located within the temporal or cerebellar cortex were less useful due to soft tissue artifacts. Frontal and parietal lobe lesions had significantly higher rates of identifying feeding arteries and draining veins (P < 0.05). CONCLUSION: Presurgical planning for resection of superficial bAVMs using Horos software allows for a comprehensive 3D analysis of the bAVM angioarchitecture. This technique is most useful for frontal and parietal lobe lesions, and aids the surgeon in formulating an optimal surgical strategy. The 3D reconstruction of the brain surface offers a surgical map not influenced by brain shift.

Optimizing the surgical management of MRI-negative epilepsy in the neuromodulation era.

OBJECTIVE: To evaluate the role of intracranial electroencephalography monitoring in diagnosing and directing the appropriate therapy for MRI-negative epilepsy and to present the surgical outcomes of patients following treatment. METHODS: Retrospective chart review between 2015-2021 at a single institution identified 48 patients with no lesion on MRI, who received surgical intervention for their epilepsy. The outcomes assessed were the surgical treatment performed and the International League Against Epilepsy seizure outcomes at 1 year of follow-up. RESULTS: Eleven patients underwent surgery without invasive monitoring, including vagus nerve stimulation (10%), deep brain stimulation (8%), laser interstitial thermal therapy (2%), and callosotomy (2%). The remaining 37 patients received invasive monitoring followed by resection (35%), responsive neurostimulation (21%), and deep brain stimulation (15%) or no treatment (6%). At 1 year postoperatively, 39% were Class 1-2, 36% were Class 3-4 and 24% were Class 5. More patients with Class 1-2 or 3-4 outcomes underwent invasive monitoring (100% and 83% respectively) compared with those with poor outcomes (25%, P < .001). Patients with Class 1-2 outcomes more commonly underwent resection or responsive neurostimulation: 69% and 31%, respectively (P < .001). SIGNIFICANCE: The optimal management of MRI-negative focal epilepsy may involve invasive monitoring followed by resection or responsive neurostimulation in most cases, as these treatments were associated with the best seizure outcomes in our cohort. Unless multifocal onset is clear from the noninvasive evaluation, invasive monitoring is preferred before pursuing deep brain stimulation or vagal nerve stimulation directly.

Management of patients with medically intractable epilepsy and anterior temporal lobe encephaloceles.

OBJECTIVE: Temporal lobe encephaloceles (TLENs) are a significant cause of medically refractory epilepsy, but there is little consensus regarding their workup and treatment. This study characterizes these lesions and their role in seizures and aims to standardize preoperative evaluation and surgical management. METHODS: Patients with TLEN who had undergone resective epilepsy surgery from December 2015 to August 2020 at a single institution were included in the study. Medical records were reviewed for each patient to collect relevant seizure workup information including demographics, radiological findings, surgical data, and neuropsychological evaluation. RESULTS: For patients who presented to the authors' program with suspected medically intractable temporal lobe epilepsy (219 patients), TLEN was considered to be the epileptogenic focus in 5.5%. Ten patients with TLEN had undergone resection and were included in this study. Concordance between ictal scalp electroencephalography (EEG) lateralization and TLEN was found in 9/10 patients (90%), and 4/10 patients (40%) had signs suggestive of idiopathic intracranial hypertension (IIH). Surgical outcome was reported in patients with at least 12 months of follow-up (9/10). Patients with scalp EEG findings concordant with the TLEN side had a good outcome (Engel class I: 7 patients, class II: 1 patient). One patient with discordant EEG findings had a bad outcome (Engel class III). No significant neuropsychological deficits were observed after the surgery. CONCLUSIONS: TLENs are epileptogenic lesions that should be screened for in patients with medically refractory epilepsy who have signs of IIH and no other lesions on MRI. Restricted resection is safe and effective in patients with scalp EEG findings concordant with TLEN.

Depth Electrode Guided Anterior Insulectomy: 2-Dimensional Operative Video.

The insula is well established as an epileptogenic area.1 Insular epilepsy surgery demands precise anatomic knowledge2-4 and tailored removal of the epileptic zone with careful neuromonitoring.5 We present an operative video illustrating an intracranial electroencephalogram (EEG) depth electrode guided anterior insulectomy. We report a 17-yr-old right-handed woman with a 4-yr history of medically refractory epilepsy. The patient reported daily nocturnal ictal vocalization preceded by an indescribable feeling. Preoperative evaluation was suggestive of a right frontal-temporal onset, but the noninvasive results were discordant. She underwent a combined intracranial EEG study with a frontal-parietal grid, with strips and depth electrodes covering the entire right hemisphere. Epileptiform activity was observed in contact 6 of the anterior insula electrode. The patient consented to the procedure and to the publication of her images. A right anterior insulectomy was performed. First, a portion of the frontal operculum was resected and neuronavigation was used for the initial insula localization. However, due to unreliable neuronavigation (ie, brain shift), the medial and anterior borders of the insular resection were guided by the depth electrode reference. The patient was discharged 3 d after surgery with no neurological deficits and remains seizure free. We demonstrate that depth electrode guided insular surgery is a safe and precise technique, leading to an optimal outcome.

Basal ganglia cavernous malformations: case series and systematic review of surgical management and long-term outcomes.

OBJECTIVE: Reports on basal ganglia cavernous malformations (BGCMs) are rare. Here, the authors report on their experience in resecting these malformations to offer insight into this infrequent disease subtype. METHODS: The authors retrospectively reviewed a prospectively managed departmental database of all deep-seated cerebral cavernous malformations (CCMs) treated at Stanford between 1987 and 2019 and included for further analysis those with a radiographic diagnosis of BGCM. Moreover, a systematic literature review was undertaken using the PubMed and Web of Science databases. RESULTS: The departmental database search yielded 331 patients with deep-seated CCMs, 44 of whom had a BGCM (13.3%). Headache was the most common presenting sign (53.5%), followed by seizure (32.6%) and hemiparesis (27.9%). Lesion location involved the caudate nucleus in 21.4% of cases compared to 78.6% of cases within the lentiform nucleus. Caudate BGCMs were larger on presentation and were more likely to present to the ependymal surface (p < 0.001) with intraventricular hemorrhage and hydrocephalus (p = 0.005 and 0.007, respectively). Dizziness and diplopia were also more common with lesions involving the caudate. Because of their anatomical location, caudate BGCMs were preferentially treated via an interhemispheric approach and were less likely to be associated with worsening perioperative deficits than lentiform BGCMs (p = 0.006 and 0.045, respectively). Ten patients (25.6%) were clinically worse in the immediate postoperative period, 4 (10.2%) of whom continued to suffer permanent morbidity at the last follow-up. A long-term good outcome (modified Rankin Scale [mRS] score 0-1) was attained in 74.4% of cases compared to the 69.2% of patients who had presented with an mRS score 0-1. Relative to their presenting mRS score, 89.8% of patients had an improved or unchanged status at the last follow-up. The median postoperative follow-up was 11 months (range 1-252 months). Patient outcomes after resection did not differ among surgical approaches; however, patients presenting with hemiparesis and lesions involving the globus pallidus or posterior limb of the internal capsule were more likely to suffer neurological deficits during the immediate perioperative period. Patients who had undergone awake surgeries were more likely to suffer neurological decline at the early as well as the late follow-up. When adjusting for awake craniotomy as a potential confounder of lesion location, a BGCM involving the posterior limb was predictive of developing early postoperative deficits, but this finding did not persist at the long-term follow-up. CONCLUSIONS: Surgery is a safe and effective treatment modality for managing BGCMs, with an estimated long-term permanent morbidity rate of around 10%.

MISIAN (Minimally Invasive Surgery for Treatment of Unruptured Intracranial Aneurysms): A Prospective Randomized Single-Center Clinical Trial With Long-Term Follow-Up Comparing Different Minimally Invasive Surgery Techniques with Standard Open Surgery.

BACKGROUND: Unruptured intracranial aneurysms (UIAs) are increasingly diagnosed but treatment is still controversial. Although the descriptions and use of minimally invasive surgery (MIS) have increased, comparative studies with standard approaches are rare. OBJECTIVE: MISIAN (Minimally Invasive Surgery for Treatment of Unruptured Intracranial Aneurysms) is a prospective randomized single-center clinical trial with long-term follow-up comparing different MIS techniques with standard open surgery for treatment of UIAs. METHODS: We randomly allocated a standard pterional approach (PtA) or MIS (1:2) to 111 patients with UIAs of the anterior circulation (mean dome diameter, 6.4 mm; range, 3-20 mm). Patients selected for MIS underwent a second randomization between a transeyelid approach (TelA) or nanopterional approach (NPtA) (1:1). RESULTS: Forty-one patients were randomized to and treated with the PtA, 36 with the TelA, and 34 with the NPtA. Only patients treated with PtA had permanent facial nerve palsy (n = 4 [10%]; P = 0.032). MIS cosmetic results were considered better than those of PtA by independent observers (P < 0.001), and less temporal atrophy in the MIS group was also observed (P = 0.0034). The proportion of excellent results was higher in the TelA group than in the NPtA group (86% vs. 67.6%; P = 0.039). Patients undergoing MIS also reported consistently higher satisfaction and quality-of-life scores (P < 0.001). CONCLUSIONS: MIS is superior to standard PtA for microsurgical clipping of small UIAs of the anterior circulation in terms of cosmetic, satisfaction, and quality-of-life outcomes. The TelA or NPtA for UIAs did not show significant outcome differences at 12-18 months.

Translamina Terminalis Approach to Laser-Assisted Resection of Thalamomesencephalic Cavernous Malformation.

Cavernous malformations of the midbrain require careful consideration of the risks and benefits of intervention as well as the optimal surgical approach for these challenging lesions. Excellent results can be achieved with careful surgical planning and technique. We demonstrate a contralateral left pterional craniotomy for a translamina terminalis approach to carbon dioxide laser-assisted microsurgical resection of a thalamomesencephalic cavernoma in a 59-year-old woman with progressive debilitating diplopia secondary to partial third nerve palsy (Video 1). We performed a contralateral left modified pterional craniotomy in which we limited dissection of the temporalis muscle to approximately one third rather than extending the muscle split down to the zygoma. The cavernous malformation was resected with no complications, and the patient was discharged from the hospital on postoperative day 3. She noted immediate improvement and nearly complete resolution of symptoms over ensuing weeks. This approach offers a direct route to the lesion with minimal brain transgression, while avoiding the critical structures within the interpeduncular cistern, including the basilar artery and thalamomesencephalic perforating arteries, as well as bordering neural structures, including cerebral peduncles, oculomotor nerves, and mamillary bodies. Use of the carbon dioxide laser with its 0.55-mm tip offers a low surgical profile and allows for precise cutting, thus minimizing thermal damage to surrounding tissues. The translamina terminalis approach through a pterional craniotomy offers a safe and potentially less morbid alternative to select thalamomesencephalic lesions compared with exposure through the mesencephalic surface, which in our experience often necessitates an orbitozygomatic craniotomy.

Incidental De Novo Cerebral Microhemorrhages are Predictive of Future Symptomatic Macrohemorrhages After Surgical Revascularization in Moyamoya Disease.

BACKGROUND: Patients with moyamoya disease who develop incidental cerebral microhemorrhages (CMHs) on magnetic resonance imaging (MRI) have higher risk of developing subsequent symptomatic repeat macro hemorrhages. OBJECTIVE: To evaluate the effect of surgical revascularization on development of de novo CMHs and assess its correlation with repeat hemorrhage rates and functional outcome in hemorrhagic onset moyamoya disease (HOMMD). METHODS: We retrospectively reviewed a prospectively managed departmental database of all patients presenting with HOMMD treated between 1987 and 2019. The search yielded 121 patients with adequate MRI follow-up for inclusion into the study. RESULTS: In total, 42 preoperative CMHs were identified in 18 patients (15%). Patients presenting with preoperative CMH were more likely to develop de novo CMH after surgical revascularization. 7 de novo CHMs were identified in 6 patients (5%) on routine postoperative MRI at distinct locations from previous sites of hemorrhage or CMH. Symptomatic repeat macro hemorrhage was confirmed radiographically in 15 patients (12%). A total 5 (83%) of 6 patients with de novo CMHs later suffered symptomatic repeat macro hemorrhage with 4 of 5 (80%) hemorrhages occurring at sites of previous CMH. On univariate and multivariate analysis, de novo CMHs was the only significant variable predictive for developing repeat symptomatic hemorrhage. Development of delayed repeat symptomatic hemorrhage was prognostic for higher modified Rankin Score and therefore poorer functional status, whereas preoperative functional status was predictive of final outcome. CONCLUSION: De novo CMHs after surgical revascularization might serve as a radiographic biomarker for refractory disease and suggest patients are at risk for future symptomatic macro hemorrhage.

Contralateral Vasospasm in an Uncomplicated Elective Anterior Communicating Artery Aneurysm Clipping.

BACKGROUND: Cerebral vasospasm following clipping of an unruptured aneurysm is a rare phenomenon. When it does occur, cerebral vasospasm usually occurs on the side ipsilateral to the surgical intervention. CASE DESCRIPTION: A 68-year-old man underwent right-sided pterional craniotomy for clipping of an unruptured anterior communicating artery aneurysm and experienced contralateral vasospasm 5 days later. CONCLUSIONS: We further discuss the pathophysiology underlying vasospasm after uncomplicated craniotomy and nonhemorrhagic aneurysm clipping.