A Phase 0/1 Pharmacokinetic and Pharmacodynamics and Safety and Tolerability Study of Letrozole in Combination with Standard Therapy in Recurrent High-Grade Gliomas

PURPOSE

High grade gliomas (HGGs) carry a poor prognosis, with glioblastoma accounting for almost 50% of primary brain malignancies in the elderly. Unfortunately, despite the use of multiple treatment modalities, the prognosis remains poor in this population. Our pre-clinical studies suggest that the presence of aromatase expression, encoded by CYP19A1, is significantly upregulated in HGGs. Remarkably, we find that letrozole (LTZ), an FDA approved aromatase inhibitor, has marked activity against HGGs.

METHODS

We conducted a phase 0/I single center clinical trial (NCT03122197) to assess the tumoral availability, pharmacokinetics (PK), safety and tolerability of LTZ in recurrent HGG patients. Planned dose cohorts included 2.5, 5, 10, 12.5, 15, 17.5 and 20 mg of LTZ administered daily pre- and post-surgery or biopsy. Tumor samples were assayed for LTZ content and relevant biomarkers. The Recommended Phase 2 Dose (R2PD) was determined as the dose that resulted in predicted steady state tumoral extracellular fluid (ECF) (Css,ecf) > 2 µM and did not result in ≥ 33% dose limiting adverse events (AEs) assessed using CTCAE v5.0.

RESULTS

Twenty-one patients were enrolled. Common LTZ related AEs included fatigue, nausea, musculoskeletal, anxiety and dysphoric mood. No DLTs were observed. The 15 mg dose achieved a Css,ecf of 3.6 +/- 0.59 µM. LTZ caused dose-dependent inhibition of estradiol synthesis and modulated DNA damage pathways in tumor tissues as evident using RNA-seq analysis.

CONCLUSION

Based on safety, brain tumoral PK, and mechanistic data, 15 mg daily is identified as the RP2D for future trials.

Cortical incisions and transcortical approaches for intra-axial and intraventricular lesions: A scoping review

Background

Transcortical approaches, encompassing various surgical corridors, have been employed to treat an array of intraparenchymal or intraventricular brain pathologies, including tumors, vascular malformations, infections, intracerebral hematomas, and epileptic surgery. Designing cortical incisions relies on the lesion location and characteristics, knowledge of eloquent functional anatomy, and advanced imaging such as tractography. Despite their widespread use in neurosurgery, there is a noticeable lack of systematic studies examining their common lobe access points, associated complications, and prevalent pathologies. This scoping review assesses current evidence to guide the selection of transcortical approaches for treating a variety of intracranial pathologies.

Methods

A scoping review was conducted using the PRISMA-ScR guidelines, searching PubMed, EMBASE, Scopus, and Web of Science. Studies were included if ≥5 patients operated on using transcortical approaches, with reported data on clinical features, treatments, and outcomes. Data analysis and synthesis were performed.

Results

A total of 50 articles encompassing 2604 patients were included in the study. The most common primary pathology was brain tumors (60.6%), particularly gliomas (87.4%). The transcortical-transtemporal approach was the most frequently identified cortical approach (70.48%), and the temporal lobe was the most accessed brain lobe (55.68%). The postoperative course outcomes were reported as good (55.52%), poor (28.38%), and death (14.62%).

Conclusion

Transcortical approaches are crucial techniques for managing a wide range of intracranial lesions, with the transcortical-transtemporal approach being the most common. According to the current literature, the selective choice of cortical incision and surgical corridor based on the lesion's pathology and anatomic-functional location correlates with acceptable functional outcomes.

Autologous cell immunotherapy (IGV-001) with IGF-1R antisense oligonucleotide in newly diagnosed glioblastoma patients

Standard-of-care first-line therapy for patients with newly diagnosed glioblastoma (ndGBM) is maximal safe surgical resection, then concurrent radiotherapy and temozolomide, followed by maintenance temozolomide. IGV-001, the first product of the Goldspire™ platform, is a first-in-class autologous immunotherapeutic product that combines personalized whole tumor-derived cells with an antisense oligonucleotide (IMV-001) in implantable biodiffusion chambers, with the intent to induce a tumor-specific immune response in patients with ndGBM. Here, we describe the design and rationale of a randomized, double-blind, phase IIb trial evaluating IGV-001 compared with placebo, both followed by standard-of-care treatment in patients with ndGBM. The primary end point is progression-free survival, and key secondary end points include overall survival and safety.

Peritrigeminal Safe Entry Zone Access to Anterolateral Pons Using the Presigmoid Retrolabyrinthine Suprameatal Approach: A Cadaveric Morphometric Study

BACKGROUND AND OBJECTIVES

Access to the anterolateral pontine lesions can be achieved through the peritrigeminal and supratrigeminal safe entry zones using Kawase, retrosigmoid, or translabyrinthine approaches. However, these approaches entail shallow extensive dissection, tangential access, and compromise vestibulocochlear function. We aimed to investigate infratentorial presigmoid retrolabyrinthine approach to access pontine lesions through the peritrigeminal zone.

METHODS

We performed 10 presigmoid retrolabyrinthine suprameatal approach dissections in 5 cadaveric heads. Anatomic-radiological characteristics and variations were evaluated. Six morphometric parameters were measured and analyzed to predict surgical accessibility.

RESULTS

The pontine infratrigeminal area was accessible in all patients. The mean exposed area of the anterolateral pontine surface was 98.95 cm 2 (±38.11 cm 2 ). The mean length of the exposed trigeminal nerve was 7.9 cm (±2.9 cm). Preoperative anatomic-radiological parameters may allow to select patients with favorable anatomy that offers appropriate surgical accessibility to the anterior pontine cavernoma through a presigmoid retrolabyrinthine corridor.

CONCLUSION

Anterolateral pontine lesions can be accessed through a minimally invasive infratentorial presigmoid retrolabyrinthine approach by targeting the infratrigeminal safe entry zone. Further clinical studies should be conducted to evaluate the viability of this technique for treating these complex pathologies in real clinical settings.

Factors associated with radiation necrosis and intracranial control in patients treated with immune checkpoint inhibitors and stereotactic radiotherapy

BACKGROUND AND PURPOSE

Emerging data suggest immune checkpoint inhibitors (ICI) and stereotactic radiosurgery (SRS) or radiotherapy (SRT) may work synergistically, potentially increasing both efficacy and toxicity. This manuscript characterizes factors associated with intracranial control and radiation necrosis in this group.

MATERIALS AND METHODS

All patients had non-small cell lung cancer, renal cell carcinoma, or melanoma and were treated from 2013 to 2021 at two institutions with ICI and SRS/SRT. Univariate and multivariate analysis were used to analyze factors associated with local failure (LF) and grade 2+ (G2 + ) radiation necrosis.

RESULTS

There were 179 patients with 549 metastases. The median follow up from SRS/SRT was 14.7 months and the median tumor size was 7 mm (46 tumors ≥ 20 mm). Rates of LF and G2 + radiation necrosis per metastasis were 5.8% (32/549) and 6.9% (38/549), respectively. LF rates for ICI +/- 1 month from time of radiation versus not were 3% (8/264) and 8% (24/285) (p = 0.01), respectively. G2 + radiation necrosis rates for PD-L1 ≥ 50% versus < 50% were 17% (11/65) and 3% (5/203) (p=<0.001), respectively. PD-L1 ≥ 50% remained significantly associated with G2 + radiation necrosis on multivariate analysis (p = 0.03). Rates of intracranial failure were 54% (80/147) and 17% (4/23) (p = 0.001) for those without and with G2 + radiation necrosis, respectively.

CONCLUSIONS

PD-L1 expression (≥50%) may be associated with higher rates of G2 + radiation necrosis, and there may be improved intracranial control following the development of radiation necrosis. Administration of ICIs with SRS/SRT is overall safe, and there may be some local control benefit to delivering these concurrently.

Transcanal Transpromontorial Approaches to the Internal Auditory Canal: A Systematic Review

OBJECTIVE

Exclusive endoscopic (EETTA) and expanded (ExpTTA) transcanal transpromontorial approaches have shown promising results for treating internal auditory canal (IAC) lesions. We reviewed the literature to answer the question: "Do EETTA and ExpTTA achieve high rates of complete resection and low rates of complications in treating patients with IAC pathologies?"

DATA SOURCES

PubMed, EMBASE, Scopus, Web of Science, and Cochrane were searched.

REVIEW METHODS

Studies reporting EETTA/ExpTTA for IAC pathologies were included. Indications and techniques were discussed and meta-analyzed rates of outcomes and complications were obtained with random-effect model meta-analyses.

RESULTS

We included 16 studies comprising 173 patients, all with non-serviceable hearing. Baseline FN function was mostly House-Brackmann-I (96.5%; 95% CI: 94.9-98.1%). Most lesions were vestibular/cochlear schwannomas (98.3%; 95% CI: 96.7-99.8%) of Koos-I (45.9%; 95% CI: 41.3-50.3%) or II (47.1%; 95% CI: 43-51.1%). EETTA was performed in 101 patients (58.4%; 95% CI: 52.4-64.3%) and ExpTTA in 72 (41.6%; 95% CI: 35.6-47.6%), achieving gross-total resection in all cases. Transient complications occurred in 30 patients (17.3%; 95% CI: 13.9-20.5%), with meta-analyzed rates of 9% (95% CI: 4-15%), comprising FN palsy with spontaneous resolution (10.4%; 95% CI: 7.7-13.1%). Persistent complications occurred in 34 patients (19.6%; 95% CI: 17.1-22.2%), with meta-analyzed rates of 12% (95% CI: 7-19%), comprising persistent FN palsy in 22 patients (12.7%; 95% CI: 10.2-15.2%). Mean follow-up was 16 months (range, 1-69; 95% CI: 14.7-17.4). Post-surgery FN function was stable in 131 patients (75.8%; 95% CI: 72.1-79.5%), worsened in 38 (21.9%; 95% CI: 18.8-25%), and improved in 4 (2.3%; 95% CI: 0.7-3.9%), with meta-analyzed rates of improved/stable response of 84% (95% CI: 76-90%).

CONCLUSION

Transpromontorial approaches offer newer routes for IAC surgery, but their restricted indications and unfavorable FN outcomes currently limit their use. Laryngoscope, 133:2856-2867, 2023.

A proposed classification system for presigmoid approaches: a scoping review

OBJECTIVE

The "presigmoid corridor" covers a spectrum of approaches using the petrous temporal bone either as a target in treating intracanalicular lesions or as a route to access the internal auditory canal (IAC), jugular foramen, or brainstem. Complex presigmoid approaches have been continuously developed and refined over the years, leading to great heterogeneity in their definitions and descriptions. Owing to the common use of the presigmoid corridor in lateral skull base surgery, a simple anatomy-based and self-explanatory classification is needed to delineate the operative perspective of the different variants of the presigmoid route. Herein, the authors conducted a scoping review of the literature with the aim of proposing a classification system for presigmoid approaches.

METHODS

The PubMed, EMBASE, Scopus, and Web of Science databases were searched from inception to December 9, 2022, following the PRISMA Extension for Scoping Reviews guidelines to include clinical studies reporting the use of "stand-alone" presigmoid approaches. Findings were summarized based on the anatomical corridor, trajectory, and target lesions to classify the different variants of the presigmoid approach.

RESULTS

Ninety-nine clinical studies were included for analysis, and the most common target lesions were vestibular schwannomas (60/99, 60.6%) and petroclival meningiomas (12/99, 12.1%). All approaches had a common entry pathway (i.e., mastoidectomy) but were differentiated into two main categories based on their relationship to the labyrinth: translabyrinthine or anterior corridor (80/99, 80.8%) and retrolabyrinthine or posterior corridor (20/99, 20.2%). The anterior corridor comprised 5 variations based on the extent of bone resection: 1) partial translabyrinthine (5/99, 5.1%), 2) transcrusal (2/99, 2.0%), 3) translabyrinthine proper (61/99, 61.6%), 4) transotic (5/99, 5.1%), and 5) transcochlear (17/99, 17.2%). The posterior corridor consisted of 4 variations based on the target area and trajectory in relation to the IAC: 6) retrolabyrinthine inframeatal (6/99, 6.1%), 7) retrolabyrinthine transmeatal (19/99, 19.2%), 8) retrolabyrinthine suprameatal (1/99, 1.0%), and 9) retrolabyrinthine trans-Trautman's triangle (2/99, 2.0%).

CONCLUSIONS

Presigmoid approaches are becoming increasingly complex with the expansion of minimally invasive techniques. Descriptions of these approaches using the existing nomenclature can be imprecise or confusing. Therefore, the authors propose a comprehensive classification based on the operative anatomy that unequivocally describes presigmoid approaches simply, precisely, and efficiently.

Neurologic Events and Outcomes in Patients Receiving Proton and Photon Reirradiation for High Grade Non-Codeleted Gliomas

PURPOSE/OBJECTIVE(S)

Patients undergoing reirradiation (ReRT) for high grade glioma are at risk for tumor progression, pseudoprogression, and radiation necrosis. We investigated factors associated with neurologic events and disease control after re-irradiation with protons and photons at a single academic center.

MATERIALS/METHODS

We reviewed records and MRIs of patients receiving scanning beam proton (since center opening in 2016) and photon (since 2015) reirradiation in ≥10 fractions for grade 3 anaplastic astrocytoma (AA) and grade 4 glioblastoma (GBM), excluding 1p19q co-deleted oligodendrogliomas and extensive multifocal/leptomeningeal disease. The primary endpoint was time from ReRT to ≥ grade 2 pseudoprogression or radiation necrosis (PsP/RN, grade 2: moderate symptoms requiring outpatient steroids/bevacizumab, grade 3: severe symptoms leading to admission or surgical intervention). Dose was converted to EQD2 using a/b = 3. Cox proportional hazards model was used to calculate survival and time to PsP/RN.

RESULTS

A total of 53 patients were included (26 protons, 27 photons, median KPS 80). Patients receiving protons had more favorable features. Compared to the photons, the proton group was younger (48 vs. 58) and more likely to have AA (46% vs. 22%) and resection within 3 months (42% vs 26%). The proton group also had a longer interval from prior RT (57 vs. 39 months) and were less likely to receive bevacizumab at reRT (15% vs. 59%). CTV was 130 cc for protons vs 99 cc for photons, and most had active disease at time of ReRT identified on planning MRI (76% protons, 85% photons). Median OS was 10.5 months (14.1 months protons, 8.1 months photons), with time from initial RT the only significant factor on multivariate analysis. Median PFS was 9.4 months (9.8 months protons, 6.2 months photons). 9 patients (18%) had ≥ grade 3 PsP/RN (8 proton, 1 photon) and 21 patients (41%) had ≥ grade 2 PsP/RN (16 proton, 5 photon). Grade 3 events included 1 seizure (photon group), 1 hemorrhage, 1 thalamic stroke, 1 shunt placement, 1 re-resection, and PSP4 4 PsP/RN requiring admission. Protons were associated shorter time to ≥ grade 2 PsP/RN (4 months vs. not reached, p = 0.027). When accounting for bevacizumab use at time of reRT, the association between protons and PsP/RN lost significance but there remained a trend (grade 2, p = 0.095, HR 2.4; grade 3, p = 0.105, HR 5.8). CTV, MGMT status, EQD2, and interval from prior RT were not associated with PsP/RN.

CONCLUSION

High grade neurologic events were common in patients with predominantly active, unresected high grade gliomas receiving ReRT. Though ascertainment and survival bias are significant limitations, pseudoprogression and necrosis appeared to be more prominent in patients receiving protons. These results contribute to ongoing efforts to both optimize ReRT for high grade glioma and investigate biologic effects of proton therapy.

Cancer stem cell assay-guided chemotherapy improves survival of patients with recurrent glioblastoma in a randomized trial

Therapy-resistant cancer stem cells (CSCs) contribute to the poor clinical outcomes of patients with recurrent glioblastoma (rGBM) who fail standard of care (SOC) therapy. ChemoID is a clinically validated assay for identifying CSC-targeted cytotoxic therapies in solid tumors. In a randomized clinical trial (NCT03632135), the ChemoID assay, a personalized approach for selecting the most effective treatment from FDA-approved chemotherapies, improves the survival of patients with rGBM (2016 WHO classification) over physician-chosen chemotherapy. In the ChemoID assay-guided group, median survival is 12.5 months (95% confidence interval [CI], 10.2-14.7) compared with 9 months (95% CI, 4.2-13.8) in the physician-choice group (p = 0.010) as per interim efficacy analysis. The ChemoID assay-guided group has a significantly lower risk of death (hazard ratio [HR] = 0.44; 95% CI, 0.24-0.81; p = 0.008). Results of this study offer a promising way to provide more affordable treatment for patients with rGBM in lower socioeconomic groups in the US and around the world.

Long-Term Results of Endoscopic Endonasal Marsupialization of Rathke Cleft Cysts With Bioabsorbable Steroid-Eluting Stents-Technical Case Series and Review of the Literature

BACKGROUND

Rathke cleft cysts (RCCs) are common benign skull-base lesions arising from embryologic remnants of Rathke pouch. Though frequently asymptomatic, RCCs can become symptomatic because of compression of adjacent neural structures. Transcranial and neuroendoscopic surgical treatments have been described for symptomatic RCCs, but recurrence rates remain as high as 30%. Bioabsorbable steroid-eluting (BASE) stents significantly decrease adhesions and recurrent ostia obstruction after endoscopic sinus surgery. We sought to use BASE stents to aid marsupialization of symptomatic RCCs.

OBJECTIVE

To present long-term results of our initial experience with endoscopic-endonasal fenestration and placement of BASE stents for RCCs.

METHODS

Patients undergoing neuroendoscopic transsphenoidal fenestration of RCCs with BASE stent placement were identified and their medical records retrospectively reviewed.

RESULTS

Four patients underwent neuroendoscopic transsphenoidal fenestration and BASE stent placement from March 2016 to April 2018 for symptomatic RCCs. After the cyst contents were evacuated, a BASE stent was deployed in the cyst fenestration to prevent cyst wall regrowth or closure and facilitate marsupialization to the sphenoid sinus. No perioperative complications were encountered, and all patients reported symptom resolution by 2 weeks postoperatively. Postoperative endoscopic evaluation demonstrated epithelization of the cyst wall opening and patent marsupialization into the sphenoid sinus in all cases. After a mean follow-up of 56 ± 12 months, all patients remained asymptomatic with baseline visual function and no radiographic evidence of recurrence.

CONCLUSION

Bioabsorbable steroid-eluting stent placement is a safe, facile, viable augmentation of neuroendoscopic technique for symptomatic RCCs with the potential to reduce long-term recurrence rates.

External Validation of an Extreme Gradient Boosting Model for Prediction of Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Delayed cerebral ischemia (DCI) may significantly worsen the functional status of patients with aneurysmal subarachnoid hemorrhage (aSAH). Several authors have designed predictive models for early identification of patients at risk of post-aSAH DCI. In this study, we externally validate an extreme gradient boosting (EGB) forecasting model for post-aSAH DCI prediction.

METHODS

A 9-year institutional retrospective review of patients with aSAH was performed. Patients were included if they underwent surgical or endovascular treatment and had available follow-up data. DCI was diagnosed as new onset neurological deficits at 4-12 days after aneurysm rupture, defined as worsening GCS for ≥2 points, and new ischemic infarcts at imaging.

RESULTS

267 patients with aSAH were collected. At admission, median Hunt-Hess score was 2 (range, 1-5), median Fisher score 3 (range, 1-4), and median modified Fisher score 3 (range, 1-4). 145 patients underwent EVD placement for hydrocephalus (54.3%). The ruptured aneurysms were treated with clipping (64%), coiling (34.8%), and stent-assisted coiling (1.1%). 58 patients (21.7%) were diagnosed with clinical DCI and 82 (30.7%) with asymptomatic imaging vasospasm. The EGB classifier correctly predicted 19 cases of DCI (7.1%) and 154 cases of no-DCI (57.7%), achieving sensitivity of 32.76% and specificity of 73.68%. The calculated F1-score and accuracy were 0.288 and 64.8%, respectively.

CONCLUSION

We validated the EGB model has a potential assistant tool to predict post-aSAH DCI in clinical practice, finding moderate-high specificity but low sensitivity. Future research should investigate the underlying pathophysiology of DCI to allow the development of high-performing forecasting models.

Brain Vasculature Color-Labeling Using the Triple-Injection Method in Cadaveric Heads: A Technical Note for Improved Teaching and Research in Neurovascular Anatomy

BACKGROUND

Color-labeling injections of cadaveric heads have revolutionized education and teaching of neurovascular anatomy. Silicone-based and latex-based coloring techniques are currently used, but limitations exist because of the viscosity of solutions used.

OBJECTIVE

To describe a novel "triple-injection method" for cadaveric cranial vasculature and perform qualitative and semiquantitative evaluations of colored solution penetration into the vasculature.

METHODS

After catheter preparation, vessel cannulation, and water irrigation of embalmed cadaveric heads, food coloring, gelatin, and silicone solutions were injected in sequential order into bilateral internal carotid and vertebral arteries (red-colored) and internal jugular veins (blue-colored). In total, 6 triple-injected embalmed cadaveric heads and 4 silicone-based "control" embalmed cadaveric heads were prepared. A qualitative analysis was performed to compare the vessel coloring of 6 triple-injected heads with that of 4 "control" heads. A semiquantitative evaluation was completed to appraise sizes of the smallest color-filled vessels.

RESULTS

Naked-eye and microscope evaluations of embalmed experimental and control cadaveric heads revealed higher intensity and more distal color-labeling following the "triple-injection method" compared with the silicone-based method in both the intracranial and extracranial vasculature. Microscope assessment of 1-mm-thick coronal slices of triple-injected brains demonstrated color-filling of distal vessels with minimum diameters of 119 μm for triple-injected heads and 773 μm for silicone-based injected heads.

CONCLUSION

Our "triple-injection method" showed superior color-filling of small-sized vessels as compared with the silicone-based injection method, resulting in more distal penetration of smaller caliber vessels.

A comprehensive analysis of tobacco smoking history as a risk for outcomes after endoscopic transsphenoidal resection of pituitary adenoma

Objectives: This study seeks to comprehensively analyze the impact of smoking history on outcomes after endoscopic transsphenoidal hypophysectomy (TSH) for pituitary adenoma. Design: Retrospective. Setting: Tertiary care center. Participants: 398 adult patients undergoing TSH for a pituitary adenoma. Main outcome measures: Clinical and tumor characteristics and operative factors were collected. Patients were categorized as never, former, or active smokers, and the pack-years of smoking history was collected. Years since cessation of smoking was obtained for former smokers. Specific outcomes included post-operative CSF leak, length of hospitalization, 30-day return to the operating room, and 30-day readmission. Smoking history details were comprehensively analyzed for association with outcomes. Results: Any history of smoking tobacco was associated with return to the operating room (OR=2.67, 95%CI: 1.05–6.76, p=0.039), which was for persistent CSF leak in 58.3%. Among patients with post-operative CSF leak, any history of smoking was associated with need for return to the operating room to repair the CSF leak (OR=5.25, 95%CI: 1.07–25.79, p=0.041). Pack-years of smoking was positively associated with a return to the operating room (OR=1.03, 95%CI: 1.01–1.06, p=0.048). In all multivariable models, all negative outcomes were significantly associated with the covariate occurrence of intra-operative CSF leak. Conclusion: This is the first study to show smoking may have a negative impact on healing of CSF leak repairs after TSH, requiring a return to the operating room. This effect appears to be dose-dependent on the smoking history. Secondarily, intra-operative CSF leak as covariate in multivariable models was significantly associated with all negative outcomes.

Effect of Recombinant Tissue Plasminogen Activator and 120-kHz Ultrasound on Porcine Intracranial Thrombus Density

Surgical intervention for the treatment of intracerebral hemorrhage (ICH) has been limited by inadequate lysis of the target thrombus. Adjuvant transcranial ultrasound exposure is hypothesized to improve thrombolysis, expedite hematoma evacuation and improve clinical outcomes. A juvenile porcine intracerebral hemorrhage model was established by direct infusion of autologous blood into the porcine white matter. Thrombi were either not treated (sham) or treated with recombinant tissue plasminogen activator alone (rt-PA only) or in combination with pulsed transcranial 120-kHz ultrasound (sonothrombolysis). After treatment, pigs were euthanized, the heads frozen and sectioned and the thrombi extracted. D-Dimer and thrombus density assays were used to assess degree of lysis. Both porcine and human D-dimer assays tested did not have sufficient sensitivity to detect porcine D-dimer. Thrombi treated with rt-PA with or without 120-kHz ultrasound had a significantly lower density compared with sham-treated thrombi. No enhancement of rt-PA-mediated thrombolysis was noted with the addition of 120-kHz ultrasound (sonothrombolysis). The thrombus density assay revealed thrombolytic efficacy caused by rt-PA in an in vivo juvenile porcine model of intracerebral hemorrhage. Transcranial sonothrombolysis did not enhance rt-PA-induced thrombolysis, likely because of the lack of exogenous cavitation nuclei.

Surgical Closure of the Eustachian Tube Through Middle Fossa and Transmastoid Approaches: A Pilot Cadaveric Anatomy Study

BACKGROUND

Cerebrospinal fluid rhinorrhea after temporal bone surgery involves drainage from the Eustachian tube (ET) into the nasopharynx, causing significant patient morbidity. Variable anatomy of the ET accounts for failures of currently used ET obliteration techniques.

OBJECTIVE

To describe the surgical anatomy of the ET and examine possible techniques for ET closure through middle fossa (MF) and transmastoid approaches.

METHODS

We described the surgical anatomy of the ET from the MF and transmastoid approaches in 5 adult cadaveric heads, measuring morphometric and surgical anatomy parameters and establishing targets for definite ET obliteration.

RESULTS

The osseous ET measured an average of 19.53 mm (±1.56 mm), with a mean diameter of 2.24 mm (±0.29 mm). The shortest distance between the greater superficial petrosal nerve and the ET junction was 6.61 mm (±0.61 mm). Shortest distances between the ET junction and the foramen spinosum and posterior border of the foramen ovale were 1.09 mm (±0.24 mm) and 2.03 mm (±0.30 mm), respectively. Closure of the cartilaginous ET may be performed by folding it in on itself, securing it by packing, suturing, or surgical clip ligation.

CONCLUSION

Definite obliteration of the cartilaginous ET appears feasible and the most definite approach to eliminate egress of cerebrospinal fluid to the nasopharynx using the MF approach. This technique may be used as an adjunct to skull base procedures where ET closure is planned.

CTNI-17. A MULTI-INSTITUTIONAL RANDOMIZED CLINICAL TRIAL COMPARING ASSAY - GUIDED CHEMOTHERAPY WITH PHYSICIAN-CHOICE TREATMENT FOR RECURRENT HIGH-GRADE GLIOMA (NCT03632135)

The presence of therapy-resistant cancer stem cells (CSCs) in recurrent high-grade glioma (HGG) patients contributes to poor clinical outcomes. The ChemoID functional anti-cancer assay targets cancer stem cells along with the bulk of the tumor cells. This trial aims to determine if ChemoID assay-guided treatment improves survival rates for recurrent HGG patients compared to the empirically physician-selected treatment. Patients with grade-III/IV recurrent glioma who failed standard of care (SOC) therapy were randomized (1:1) between two intervention groups. They received one of fourteen mono or combination chemotherapies based on the ChemoID assay or physician choice. The study met the primary outcome in the first interim analysis of 50 patients as per protocol. The ChemoID group had an improved survival rate (vs physician-choice). Median OS (mOS) was 12.5 months in the ChemoID group (95% CI, 10.2-14.7) vs 9 months in the physician-choice (95% CI, 4.2-13.8; log-rank P = .010). Mortality risk was lower in the ChemoID group (HR = 0.44; 95% CI, 0.24-0.81; P = .008). Median progression-free survival was 10.1 months in the ChemoID group vs 3.5 months in the physician choice (95% CI, 4.8-15.4 vs 1.9-5.1; log-rank &lt; 0.001). Risk of progression was lower in the ChemoID group (HR = 0.25; 95% CI, 0.14-0.44; P &lt; 0.001). The intention to treat (ITT) analysis of 78 patients showed substantially improved OS. The ChemoID group had a statistically significant longer median survival of 4.5 months. mOS was 12.0 months in the ChemoID group (95% CI, 10.8-13.2) vs 7.5 in the physician-choice group (95% CI, 3.5-11.5; log-rank P = .009). The ChemoID group had a decreased mortality risk (HR = 0.52; 95% CI, 0.24-0.81; P = .008). Compared with the physician-choice, the ChemoID group had a significantly longer OS in the ITT population. Our findings support that screening standard cytotoxic chemotherapies with a patient-specific anti-cancer assay improves survival outcomes in recurrent HGG patients.

Evaluate the safety and efficacy of dura sealant patch in reducing cerebrospinal fluid leakage following elective cranial surgery (ENCASE II): study protocol for a randomized, two-arm, multicenter trial

BACKGROUND

Cerebrospinal fluid (CSF) leakage is a frequent and challenging complication in neurosurgery, especially in the posterior fossa, with a prevalence of 8%. It is associated with substantial morbidity and increased healthcare costs. A novel dural sealant patch (LIQOSEAL) was developed for watertight dural closure. The objective of this study is to clinically assess the safety and effectiveness of LIQOSEAL as a means of reducing intra- as well as postoperative CSF leakage in patients undergoing elective posterior fossa intradural surgery with a dural closure procedure compared to the best currently available dural sealants.

METHODS

We will conduct a two-arm, randomized controlled, multicenter study with a 90-day follow-up. A total of 228 patients will be enrolled in 19 sites, of which 114 will receive LIQOSEAL and 114 an FDA-approved PEG sealant. The composite primary endpoint is defined as intraoperative CSF leakage at PEEP 20 cm H₂O, percutaneous CSF leakage within 90 days of, wound infection within 90 days of or pseudomeningocele of more than 20cc on MRI or requiring intervention. We hypothesize that the primary endpoint will not be reached by more than 10 patients (9%) in the investigational arm, which will demonstrate non-inferiority of LIQOSEAL compared to control.

DISCUSSION

This trial will evaluate whether LIQOSEAL is non-inferior to control as a means of reducing CSF leakage and safety TRIAL REGISTRATION: ClinicalTrials.gov NCT04086550 . Registered on 11 September 2019.

Roadmap to Ventral Craniocervical Junction Through the Endonasal Corridor: Anatomic Evaluation of Inverted U-Shaped Nasopharyngeal Flap Exposure in a Cadaveric Study

BACKGROUND

There is a paucity of data in the literature describing quantitative exposure of the ventral craniocervical junction through the endonasal corridor in a safe manner mindful of locoregional anatomy.

OBJECTIVE

To quantify ventromedial exposure of O-C1 and C1-2 articular structures after turning an inverted U-shaped nasopharyngeal flap (IUNF) and to obtain measurements assessing the distance of flap margins to adjacent neurovascular structures.

METHODS

In 8 cadaveric specimens, an IUNF was fashioned using a superior incision below the level of the pharyngeal tubercule of the clivus and lateral incisions in the approximate region of Rosenmuller fossae bilaterally. Measurements with calipers and/or neuronavigation software included flap dimensions, exposure of O-C1 and C1-2 articular structures, inferior reach of IUNF, and proximity of the internal carotid artery (ICA) and hypoglossal nerve to IUNF margins.

RESULTS

The IUNF facilitated exposure of an average of 9 mm of the medial surfaces of the right/left O-C1 joints without transgression of the carotid arteries or hypoglossal nerves. The C1-2 articulation could not be routinely accessed. The margins of the IUNF were not in close (<5 mm) proximity to the ICA in any of the 8 specimens. In 6 of 8 specimens, the dimensions of the IUNF were in close (<5 mm) horizontal or vertical proximity to the hypoglossal foramina.

CONCLUSION

The IUNF provided safe and reliable access to the medial O-C1 articulation. Given the close proximity of the exocranial hypoglossal foramen, neuronavigation assistance and neuromonitoring with attention to the superolateral IUNF margin are recommended.

Cochlear Fibrosis after Vestibular Schwannoma Resection via the Middle Cranial Fossa Approach

OBJECTIVE

The aim of this study was to determine the incidence of cochlear fibrosis after vestibular schwannoma (VS) resection via middle cranial fossa (MCF) approach.

DESIGN

A retrospective case review was conducted.

SETTING

The review was conducted in a tertiary care academic medical center.

PARTICIPANTS

Patients who (1) underwent resection of VS via MCF approach between 2013 and 2018, (2) had complete pre- and post-audiometric testing, and (3) had clinical follow-up with magnetic resonance imaging (MRI) for at least 1 year after surgery were included.

MAIN OUTCOME MEASURE(S)

The main outcome of this study was cochlear fibrosis as assessed by MRI 1 year after surgery.

RESULTS

Fifty-one patients underwent VS resection via MCF technique during the study period. Of 31 patients with AAO-HNS class A or B preoperative hearing ability, 18 (58.0%) maintained class A, B, or C hearing postoperatively. Of 16 patients who lost hearing and had MRI 1 year after surgery, 11 (61.1%) had MRI evidence of fibrosis in at least some portion of the labyrinth and 4 (22.2%) showed evidence of cochlear fibrosis. Of 16 patients with preserved hearing and MRI 1 year after surgery, 4 (25%) had fibrosis in some portion of the labyrinth, with no fibrosis in the cochlea.

CONCLUSIONS

In patients who lose hearing during VS resection with the MCF approach, there is usually MRI evidence of fibrosis in the labyrinth 1 year after surgery. However, there is also, but less commonly, fibrosis involving the cochlea. It is unclear if this will affect the ability to insert a cochlear implant electrode array.

2D versus 3D Endoscopy: Head-to-Head Comparison in a Simulated Model of Endoscopic Endonasal Dural Suturing

Objective Endonasal dural suturing (EDS) has been reported to decrease the incidence of cerebrospinal fluid fistula. This technique requires handling of single-shaft instrumentation in the narrow endonasal corridor. It has been proposed that three-dimensional (3D) endoscopes were associated with improved depth perception. In this study, we sought to perform a comparison of two-dimensional (2D) versus 3D endoscopy by assessing surgical proficiency in a simulated model of EDS.

Materials and Methods Twenty-six participants subdivided into groups based on previous endoscopic experience were asked to pass barbed sutures through preset targets with either 2D (Storz Hopkins II) or 3D (Storz TIPCAM) endoscopes on 3D-printed simulation model. Surgical precision and procedural time were measured. All participants completed a Likert scale questionnaire.

Results Novice, intermediate, and expert groups took 11.0, 8.7, and 5.7 minutes with 2D endoscopy and 10.9, 9.0, and 7.6 minutes with 3D endoscopy, respectively. The average deviation for novice, intermediate, and expert groups (mm) was 5.5, 4.4, and 4.3 with 2D and 6.6, 4.6, and 3.0 with 3D, respectively. No significant difference in procedural time or accuracy was found in 2D versus 3D endoscopy. 2D endoscopic visualization was preferred by the majority of expert/intermediate participants, while 3D endoscopic visualization by the novice group.

Conclusion In this pilot study, there was no statistical difference in procedural time or accuracy when utilizing 2D versus 3D endoscopes. While it is possible that widespread familiarity with 2D endoscopic equipment has biased this study, preliminary analysis suggests that 3D endoscopy offers no definitive advantage over 2D endoscopy in this simulated model of EDS.

Insights into potential targeted nonsurgical therapies for the treatment of moyamoya disease

Since its initial description in 1957 as an idiopathic disease, moyamoya disease has proved challenging to treat. Although the basic pathophysiology of this disease involves narrowing of the terminal carotid artery with compensatory angiogenesis, the molecular and cellular mechanisms underlying these changes are far more complex. In this article, the authors review the literature on the molecular and cellular pathophysiology of moyamoya disease with an emphasis on potential therapeutic targets.

Extended Middle Cranial Fossa Approach for Placement of Auditory Brainstem Implants

OBJECTIVE

Traditionally, auditory brainstem implants (ABIs) have been placed via the translabyrinthine or retrosigmoid approaches. In select patients, a modified extended middle cranial fossa (xMCF) approach with tentorial ligation may be advantageous for vestibular schwannoma (VS) resection and auditory rehabilitation. This manuscript describes the application of this modification of the MCF approach for simultaneous VS resection and ABI placement.

PATIENTS

Patients with neurofibromatosis type 2, profound bilateral sensorineural hearing loss, single functioning sigmoid/jugular venous system, and giant (>4 cm) VS.

INTERVENTIONS

Simultaneous VS resection and ABI placement via a modified xMCF approach with tentorial ligation.

MAIN OUTCOME MEASURES

Extent of tumor removal and brainstem decompression, access to lateral recess of the fourth ventricle, functional hearing improvement, surgical complications.

RESULTS

Two patients met indications and underwent surgery. There were no immediate or delayed surgical complications. Both had subtotal tumor removal with significant decompression of the brainstem and ABI placement. One patient achieved voice and environmental sound awareness at 35 to 55 dbHL across frequencies. The second patient presented with failure to thrive and multiple lower cranial neuropathies in addition to the above-listed indications. She was hospitalized multiple times after surgery due to failure to thrive and recurrent aspiration pneumonia. Her device was never activated, and she expired 1 year after surgery.

CONCLUSIONS

The xMCF with tentorial ligation is an additional approach for tumor resection and ABI placement in selected patients with neurofibromatosis type 2. Future studies will further define when this approach is most applicable as well as the challenges and pitfalls.

Intracerebral Hemorrhage Volume Reduction and Timing of Intervention Versus Functional Benefit and Survival in the MISTIE III and STICH Trials

BACKGROUND

The extent of intracerebral hemorrhage (ICH) removal conferred survival and functional benefits in the minimally invasive surgery with thrombolysis in intracerebral hemorrhage evacuation (MISTIE) III trial. It is unclear whether this similarly impacts outcome with craniotomy (open surgery) or whether timing from ictus to intervention influences outcome with either procedure.

OBJECTIVE

To compare volume evacuation and timing of surgery in relation to outcomes in the MISTIE III and STICH (Surgical Trial in Intracerebral Hemorrhage) trials.

METHODS

Postoperative scans were performed in STICH II, but not in STICH I; therefore, surgical MISTIE III cases with lobar hemorrhages (n = 84) were compared to STICH II all lobar cases (n = 259) for volumetric analyses. All MISTIE III surgical patients (n = 240) were compared to both STICH I and II (n = 722) surgical patients for timing analyses. These were investigated using cubic spline modeling and multivariate risk adjustment.

RESULTS

End-of-treatment ICH volume ≤28.8 mL in MISTIE III and ≤30.0 mL in STICH II had increased probability of modified Rankin Scale (mRS) 0 to 3 at 180 d (P = .01 and P = .003, respectively). The effect in the MISTIE cohort remained significant after multivariate risk adjustments. Earlier surgery within 62 h of ictus had a lower probability of achieving an mRS 0 to 3 at 180 d with STICH I and II (P = .0004), but not with MISTIE III. This remained significant with multivariate risk adjustments. There was no impact of timing until intervention on mortality up to 47 h with either procedure.

CONCLUSION

Thresholds of ICH removal influenced outcome with both procedures to a similar extent. There was a similar likelihood of achieving a good outcome with both procedures within a broad therapeutic time window.

Thrombolysis for Evacuation of Intracerebral and Intraventricular Hemorrhage: A Guide to Surgical Protocols With Practical Lessons Learned From the MISTIE and CLEAR Trials

BACKGROUND

Minimally Invasive Surgery Plus Recombinant Tissue Plasminogen Activator for Intracerebral Hemorrhage Evacuation (MISTIE) procedure was recently tested in a large phase III randomized trial showing a significant probability of functional benefit in those cases that reached the goal hematoma evacuation of ≤15 mL residual (or ≥70% removal). Benefit of thrombolysis was also identified in cases with large intraventricular hemorrhage, and achieving at least 85% volume reduction in the Evaluating Accelerated Resolution of Intraventricular Hemorrhage (CLEAR) III trial.

OBJECTIVE

To protocolize steps in the MISTIE and CLEAR procedures in order to maximize hematoma evacuation and minimize complications.

METHODS

We articulate data-driven lessons and expert opinions surrounding the factors of patient selection, catheter placement, and dosing, which impacted safety and surgical performance in the MISTIE and CLEAR trials.

RESULTS

Modifiable factors to maximize evacuation efficiency include optimizing catheter placement and pursuing aggressive dosing to achieve treatment goals, while strictly adhering to the safety steps as articulated in the respective trials. Prognostic factors that are viewed as nonmodifiable include greater initial intracerebral hemorrhage volume with irregular shape, smaller intraventricular bleeds, and the uncommon but consequential development of new bleeding during the dosing period despite strict protocol adherence.

CONCLUSIONS

Surgeon education in this tutorial is aimed at maximizing the benefit of the MISTIE and CLEAR procedures by reviewing case selection, safety steps, treatment objectives, and technical nuances. Key lessons include stability imaging, etiology screening, and technical adherence to the protocol in order to achieve defined thresholds of evacuation.

Multi-Disciplinary Skull Base Conference and its Effects on Patient Management

OBJECTIVE

Examine the effects of a multi-disciplinary skull base conference (MDSBC) on the management of patients seen for skull base pathology in a neurotology clinic.

METHODS

Retrospective case review of patients who were seen in a neurotology clinic at a tertiary academic medical center for pathology of the lateral skull base and were discussed at an MDSBC between July 2019 and February 2020. Patient characteristics, nature of the skull base pathology, and pre- and post-MDSBC plan of care was categorized.

RESULTS

A total of 82 patients with pathology of the lateral skull base were discussed at a MDSBC during an 8-month study period. About 54 (65.9%) had a mass in the internal auditory canal and/or cerebellopontine angle while 28 (34.1%) had other pathology of the lateral skull base. Forty-nine (59.8%) were new patients and 33 (40.2%) were established. The management plan changed in 11 (13.4%, 7.4-22.6 95% CI) patients as a result of the skull base conference discussion. The planned management changed from some form of treatment to observation in 4 patients, and changed from observation to some form of treatment in 4 patients. For 3 patients who underwent surgery, the planned approach was altered.

CONCLUSIONS

For a significant proportion of patients with pathology of the lateral skull base, the management plan changed as a result of discussion at an MDSBC. Although participants of a MDSBC would agree of its importance, it is unclear how an MDSBC affects patient outcomes.

Minimally-invasive tubular retraction ports for intracranial neurosurgery: History and future perspectives

Brain retraction is a necessary yet potentially damaging requirement of accessing lesions located in deep structures. The development of minimally-invasive tubular retractors (MITRs) provides the theoretical advantage of maximizing visualization of and access to deep-seated lesions, all while minimizing collateral tissue damage. These advantages make MITRs preferable to traditional bladed retractors in the majority of deep-seated lesions. Several commercially-available MITR systems currently exist and have been shown to aid in achieving excellent outcomes with acceptable safety profiles. Nevertheless, important drawbacks to currently-available MITR systems exist. Continued pursuit of an ideal MITR system that provides maximal visualization and access to deep-seated lesions while minimizing retraction-related tissue damage is therefore important. In this review, we discuss the historical development of MITRs, the advantages of MITRs compared to traditional bladed retractors, and opportunities to improve the development of prospective MITRs.

Leukocyte dynamics after intracerebral hemorrhage in a living patient reveal rapid adaptations to tissue milieu

Intracerebral hemorrhage (ICH) is a devastating form of stroke with a high mortality rate and few treatment options. Discovery of therapeutic interventions has been slow given the challenges associated with studying acute injury in the human brain. Inflammation induced by exposure of brain tissue to blood appears to be a major part of brain tissue injury. Here, we longitudinally profiled blood and cerebral hematoma effluent from a patient enrolled in the Minimally Invasive Surgery with Thrombolysis in Intracerebral Hemorrhage Evacuation trial, offering a rare window into the local and systemic immune responses to acute brain injury. Using single-cell RNA-Seq (scRNA-Seq), this is the first report to our knowledge that characterized the local cellular response during ICH in the brain of a living patient at single-cell resolution. Our analysis revealed shifts in the activation states of myeloid and T cells in the brain over time, suggesting that leukocyte responses are dynamically reshaped by the hematoma microenvironment. Interestingly, the patient had an asymptomatic rebleed that our transcriptional data indicated occurred prior to detection by CT scan. This case highlights the rapid immune dynamics in the brain after ICH and suggests that sensitive methods such as scRNA-Seq would enable greater understanding of complex intracerebral events.

MRI T2-Hyperintense Signal Structures in the Cervical Spinal Cord: Anterior Median Fissure versus Central Canal in Chiari and Control-An Exploratory Pilot Analysis

BACKGROUND AND PURPOSE

Cervical spine axial MRI T2-hyperintense fluid signal of the anterior median fissure and round hyperintense foci resembling either the central canal or base of the anterior median fissure are associated with a craniocaudad sagittal line, also simulating the central canal. On the basis of empiric observation, we hypothesized that hyperintense foci, the anterior median fissure, and the sagittal line are seen more frequently in patients with Chiari malformation type I, and the sagittal line may be the base of the anterior median fissure in some patients.

MATERIALS AND METHODS

Saggital line incidence and the incidence/frequency of hyperintense foci and anterior median fissure in 25 patients with Chiari I malformation and 25 contemporaneous age-matched controls were recorded in this prospective exploratory study as either combined (hyperintense foci+anterior median fissure in the same patient), connected (anterior median fissure extending to and appearing to be connected with hyperintense foci), or alone as hyperintense foci or an anterior median fissure. Hyperintense foci and anterior median fissure/patient, hyperintense foci/anterior median fissure ratios, and anterior median fissure extending to and appearing to be connected with hyperintense foci were compared in all, in hyperintense foci+anterior median fissure in the same patient, and in anterior median fissure extending to and appearing to be connected with hyperintense foci in patients with Chiari I malformation and controls.

RESULTS

Increased sagittal line incidence (56%), hyperintense foci (8.5/patient), and anterior median fissure (4.0/patient) frequency were identified in patients with Chiari I malformation versus controls (28%, 3.9/patient, and 2.7/patient, respectively). Increased anterior median fissure/patient, decreasing hyperintense foci/anterior median fissure ratio, and increasing anterior median fissure extending to and appearing to be connected with hyperintense foci/patient were identified in Chiari subgroups. A 21%-58% increase in observed anterior median fissure extending to and appearing connected to hyperintense foci in the entire cohort and multiple sagittal line subgroups compared with predicted occurred.

CONCLUSIONS

In addition to the anticipated increased incidence/frequency of sagittal line and hyperintense foci in patients with Chiari I malformation, an increased incidence and frequency of anterior median fissure and anterior median fissure extending to and appearing to be connected with hyperintense foci/patient were identified. We believe an anterior median fissure may contribute to a saggital line appearance in some patients with Chiari I malformation. While thin saggital line channels are usually ascribed to the central canal, we believe some may be due to the base of the anterior median fissure, created by pulsatile CSF hydrodynamics.

Longitudinal transcriptomics define the stages of myeloid activation in the living human brain after intracerebral hemorrhage

Opportunities to interrogate the immune responses in the injured tissue of living patients suffering from acute sterile injuries such as stroke and heart attack are limited. We leveraged a clinical trial of minimally invasive neurosurgery for patients with intracerebral hemorrhage (ICH), a severely disabling subtype of stroke, to investigate the dynamics of inflammation at the site of brain injury over time. Longitudinal transcriptional profiling of CD14⁺ monocytes/macrophages and neutrophils from hematomas of patients with ICH revealed that the myeloid response to ICH within the hematoma is distinct from that in the blood and occurs in stages conserved across the patient cohort. Initially, hematoma myeloid cells expressed a robust anabolic proinflammatory profile characterized by activation of hypoxia-inducible factors (HIFs) and expression of genes encoding immune factors and glycolysis. Subsequently, inflammatory gene expression decreased over time, whereas anti-inflammatory circuits were maintained and phagocytic and antioxidative pathways up-regulated. During this transition to immune resolution, glycolysis gene expression and levels of the potent proresolution lipid mediator prostaglandin E₂ remained elevated in the hematoma, and unexpectedly, these elevations correlated with positive patient outcomes. Ex vivo activation of human macrophages by ICH-associated stimuli highlighted an important role for HIFs in production of both inflammatory and anti-inflammatory factors, including PGE₂, which, in turn, augmented VEGF production. Our findings define the time course of myeloid activation in the human brain after ICH, revealing a conserved progression of immune responses from proinflammatory to proresolution states in humans after brain injury and identifying transcriptional programs associated with neurological recovery.

Surgical Interventions for Supratentorial Intracranial Hemorrhage: The Past, Present, and Future

Spontaneous supratentorial intracranial hemorrhage is extremely disabling and is associated with high mortality. Primary treatment for patients with this disease process is maximal medical management with blood pressure control and correction of clotting disorders due to comorbid conditions or medications. Over the past decade, significant strides have been made in understanding the benefits of surgical intervention in the treatment of intracranial hemorrhage through multiple clinical trials. In this article, we review the evolution of surgical treatments beginning with the STICH trials, discuss new developments with minimally invasive surgical strategies, and provide a brief update regarding ongoing trials and future directions in the treatment of spontaneous supratentorial intracranial hemorrhage.

Surgical Performance Determines Functional Outcome Benefit in the Minimally Invasive Surgery Plus Recombinant Tissue Plasminogen Activator for Intracerebral Hemorrhage Evacuation (MISTIE) Procedure

BACKGROUND

Minimally invasive surgery procedures, including stereotactic catheter aspiration and clearance of intracerebral hemorrhage (ICH) with recombinant tissue plasminogen activator hold a promise to improve outcome of supratentorial brain hemorrhage, a morbid and disabling type of stroke. A recently completed Phase III randomized trial showed improved mortality but was neutral on the primary outcome (modified Rankin scale score 0 to 3 at 1 yr).

OBJECTIVE

To assess surgical performance and its impact on the extent of ICH evacuation and functional outcomes.

METHODS

Univariate and multivariate models were used to assess the extent of hematoma evacuation efficacy in relation to mRS 0 to 3 outcome and postulated factors related to patient, disease, and protocol adherence in the surgical arm (n = 242) of the MISTIE trial.

RESULTS

Greater ICH reduction has a higher likelihood of achieving mRS of 0 to 3 with a minimum evacuation threshold of ≤15 mL end of treatment ICH volume or ≥70% volume reduction when controlling for disease severity factors. Mortality benefit was achieved at ≤30 mL end of treatment ICH volume, or >53% volume reduction. Initial hematoma volume, history of hypertension, irregular-shaped hematoma, number of alteplase doses given, surgical protocol deviations, and catheter manipulation problems were significant factors in failing to achieve ≤15 mL goal evacuation. Greater surgeon/site experiences were associated with avoiding poor hematoma evacuation.

CONCLUSION

This is the first surgical trial reporting thresholds for reduction of ICH volume correlating with improved mortality and functional outcomes. To realize the benefit of surgery, protocol objectives, surgeon education, technical enhancements, and case selection should be focused on this goal.

Extended Anterior Petrosectomy Through the Transcranial Middle Fossa Approach and Extended Endoscopic Transsphenoidal-Transclival Approach: Qualitative and Quantitative Anatomic Analysis

BACKGROUND

Petroclival tumors and ventrolateral lesions of the pons present unique surgical challenges. This cadaveric study provides qualitative and quantitative anatomic comparison for an anterior petrous apicectomy through the transcranial middle fossa (TMF) and expanded endoscopic transsphenoidal-transclival approaches.

METHODS

In 10 silicone-injected heads, the petrous apex and clivus were drilled extradurally using middle fossa and endonasal approaches. With in situ and frameless stereotactic navigation, we defined consistent points to compare working areas, bone removal volumes, approach angles, and surgical freedom.

RESULTS

Mean exposed TMF area (21.03 ± 3.46 cm²) achieved a 44.71 ± 4.13° working angle to the brainstem between cranial nerves V and VI. Kawase's rhomboid area measured 1.76 ± 0.34 cm², and bone removal averaged 1.20 ± 0.12 cm³ at the petrous apex. Surgical freedom on the lateral brainstem was higher halfway between cranial nerves V and VI at the center of the rhomboid compared with midline at the basilar sulcus (P < 0.01). After clivectomy and petrous apicectomy, mean exposed expanded endoscopic transsphenoidal-transclival area was 5.29 ± 0.66 cm². Approach from either nostril showed no statistically significant differences in surgical freedom at the foramen lacerum and midpoint basilar sulcus. At the petrous apex, bone volume removed and area exposed were significantly larger for the TMF approach (P < 0.001).

CONCLUSIONS

Expanded transclival anterior petrosectomy through the TMF approach provides an adequate corridor to lesions in the upper ventrolateral pons. The expanded endoscopic transsphenoidal-transclival approach better fits midline lesions not extending laterally beyond cranial nerve VI and C3 carotid when evaluating normal anatomic parameters.

Relationship of White Matter Lesions with Intracerebral Hemorrhage Expansion and Functional Outcome: MISTIE II and CLEAR III

BACKGROUND/OBJECTIVE

Intracerebral hemorrhage (ICH) patients commonly have concomitant white matter lesions (WML) which may be associated with poor outcome. We studied if WML affects hematoma expansion (HE) and post-stroke functional outcome in a post hoc analysis of patients from randomized controlled trials.

METHODS

In ICH patients from the clinical trials MISTIE II and CLEAR III, WML grade on diagnostic computed tomography (dCT) scan (dCT, < 24 h after ictus) was assessed using the van Swieten scale (vSS, range 0-4). The primary outcome for HE was > 33% or > 6 mL ICH volume increase from dCT to the last pre-randomization CT (< 72 h of dCT). Secondary HE outcomes were: absolute ICH expansion, > 10.4 mL total clot volume increase, and a subgroup analysis including patients with dCT < 6 h after ictus using the primary HE definition of > 33% or > 6 mL ICH volume increase. Poor functional outcome was assessed at 180 days and defined as modified Rankin Scale (mRS) ≥ 4, with ordinal mRS as a secondary endpoint.

RESULTS

Of 635 patients, 55% had WML grade 1-4 at dCT (median 2.2 h from ictus) and 13% had subsequent HE. WML at dCT did not increase the odds for primary or secondary HE endpoints (P ≥ 0.05) after adjustment for ICH volume, intraventricular hemorrhage volume, warfarin/INR > 1.5, ictus to dCT time in hours, age, diabetes mellitus, and thalamic ICH location. WML increased the odds for having poor functional outcome (mRS ≥ 4) in univariate analyses (vSS 4; OR 4.16; 95% CI 2.54-6.83; P < 0.001) which persisted in multivariable analyses after adjustment for HE and other outcome risk factors.

CONCLUSIONS

Concomitant WML does not increase the odds for HE in patients with ICH but increases the odds for poor functional outcome.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov trial-identifiers: NCT00224770 and NCT00784134.

Abstract WMP103: Comparative Impact of Extent of Lobar Intracerebral Hemorrhage Removal on Outcome in the MISTIE III and STICH II Trials

Introduction: The Minimally Invasive Surgery Plus Recombinant Tissue Plasminogen Activator for Intracerebral Hemorrhage Evacuation Phase III trial (MISTIE III) concluded that the extent of hematoma reduction confers a mortality and functional benefit. It is unclear if a minimum extent of evacuation is needed for mortality and functional outcome benefit in lobar cases with MISTIE and with open surgical interventions.

Objective: We analyzed the effect of extent of lobar ICH evacuation on clinical outcome at 180 days after undergoing the MISTIE procedure and open craniotomy, in the context of the MISTIE III and STICH II clinical trials, respectively.

Methods: Patients randomized to the surgical arm with lobar ICH, who underwent the procedure in the MISTIE III trial (n=84) and the STICH II trial (n=266) were analyzed, excluding cases crossing over to surgery. We assessed end of treatment ICH volume on post procedure CT scans and % hematoma evacuation, in relation to survival and likelihood of mRS 0-3. Cubic spline modeling with dichotomized outcome was used to compare the extent of hematoma evacuation on clinical outcome.

Results: End of treatment volume of < 28 mL in lobar ICH MISTIE III patients and < 30 mL in STICH II trial patients showed a significantly increased probability of achieving an mRS of 0-3 at 180 days (p<0.03, p<0.006, respectively). This threshold was achieved in 83.1% of lobar cases undergoing MISTIE and in 92.1% of surgical cases in STICH II. Achieving survival benefit at 180 days trended towards improved probability with further hematoma volume reduction without a threshold value in MISTIE III, and was significant per mL reduction in STICH II (p<0.001). Analysis by percent of hematoma evacuation trended toward better probabilities of survival and improved functional outcome but were not significant.

Conclusion: This analysis confirms that extent of hematoma evacuation is important in attaining the benefits of both minimally invasive and open surgical interventions in non-herniating lobar ICH patients randomized in clinical trials. Extent of ICH evacuation must be considered in the analysis of comparative effectiveness of various techniques and in the design of future trials.

Abstract TP335: Comparative Impact of Timing From Ictus to Intracerebral Hemorrhage Evacuation on Outcome in MISTIE III, STICH I & II Trials

Introduction: Completion of the MISTIE procedure requires a period of hematoma stability before and during hematoma removal and, if necessary, dosing of rtPA which can take days to complete. Early surgery was intended in the STICH I and II trials, yet was performed after varying delays. No previous analysis has evaluated the timing for hematoma removal on outcomes in these trials.

Objective: Determine if time from ictus to completion of hematoma removal may have affected patient outcome in three large surgical clinical trials of ICH evacuation.

Methods: Patients randomized to surgery in the MISTIE III (n=242), STICH I (n=464) and STICH II (n=266) trials who received the procedure were analyzed, excluding cases crossing over to surgery. Time from ictus to end of treatment, defined as 24 hours after last dose in (MISTIE III) or time to craniotomy (STICH I and II), was analyzed in relation to likelihood of survival and functional outcome at 180 days. Cubic spline models with dichotomized outcomes were used.

Results: The probability of achieving an mRS 0-3 increased significantly with longer time until completion of the procedure, up to 83 hours post-ictus, and worsened with longer delays thereafter (p=0.05). Better mRS was also achieved in STICH I patients with longer time until surgical removal, up to 60 hours post-ictus (p=0.0002), but not with longer delays (p=0.49). In STICH II (lobar cases), there was greater likelihood of mRS 0-3 with longer delay after 22 hours post-ictus (p=0.004), but not with earlier surgery (p=0.19). There was no significant benefit in survival, with earlier intervention across modalities and trials. Adjustment by initial hematoma volume further validated that early procedures do not favor survival or achieving a mRS 0-3.

Conclusion: Early hematoma evacuation up to 60-80 hours post-ictus does not increase the probability of survival nor a good functional outcome in non-herniating ICH patients included in clinical trials, likely in view of bleeding instability. This was true in minimally invasive intervention as well as open surgeries.

Understanding the complex pathophysiology of idiopathic intracranial hypertension and the evolving role of venous sinus stenting: a comprehensive review of the literature

Idiopathic intracranial hypertension (IIH) is a disease defined by elevated intracranial pressure without established etiology. Although there is now consensus on the definition of the disorder, its complex pathophysiology remains elusive. The most common clinical symptoms of IIH include headache and visual complaints. Many current theories regarding the etiology of IIH focus on increased secretion or decreased absorption of cerebrospinal fluid (CSF) and on cerebral venous outflow obstruction due to venous sinus stenosis. In addition, it has been postulated that obesity plays a role, given its prevalence in this population of patients. Several treatments, including optic nerve sheath fenestration, CSF diversion with ventriculoperitoneal or lumboperitoneal shunts, and more recently venous sinus stenting, have been described for medically refractory IIH. Despite the availability of these treatments, no guidelines or standard management algorithms exist for the treatment of this disorder. In this paper, the authors provide a review of the literature on IIH, its clinical presentation, pathophysiology, and evidence supporting treatment strategies, with a specific focus on the role of venous sinus stenting.

Endoscopic transorbital superior eyelid approach: anatomical study from a neurosurgical perspective

OBJECTIVERecent studies have proposed the superior eyelid endoscopic transorbital approach as a new minimally invasive route to access orbital lesions, mostly in otolaryngology and maxillofacial surgeries. The authors undertook this anatomical study in order to contribute a neurosurgical perspective, exploring the anterior and middle cranial fossa areas through this purely endoscopic transorbital trajectory.METHODSAnatomical dissections were performed in 10 human cadaveric heads (20 sides) using 0° and 30° endoscopes. A step-by-step description of the superior eyelid transorbital endoscopic route and surgically oriented classification are provided.RESULTSThe authors' cadaveric prosection of this approach defined 3 modular routes that could be combined. Two corridors using bone removal lateral to the superior and inferior orbital fissures exposed the middle and anterior cranial fossa (lateral orbital corridors to the anterior and middle cranial base) to unveil the temporal pole region, lateral wall of the cavernous sinus, middle cranial fossa floor, and frontobasal area (i.e., orbital and recti gyri of the frontal lobe). Combined, these 2 corridors exposed the lateral aspect of the lesser sphenoid wing with the Sylvian region (combined lateral orbital corridor to the anterior and middle cranial fossa, with lesser sphenoid wing removal). The medial corridor, with extension of bone removal medially to the superior and inferior orbital fissure, afforded exposure of the opticocarotid area (medial orbital corridor to the opticocarotid area).CONCLUSIONSAlong with its minimally invasive nature, the superior eyelid transorbital approach allows good visualization and manipulation of anatomical structures mainly located in the anterior and middle cranial fossae (i.e., lateral to the superior and inferior orbital fissures). The visualization and management of the opticocarotid region medial to the superior orbital fissure are more complex. Further studies are needed to prove clinical applications of this relatively novel surgical pathway.

A randomized 500-subject open-label phase 3 clinical trial of minimally invasive surgery plus alteplase in intracerebral hemorrhage evacuation (MISTIE III)

RATIONALE AND HYPOTHESIS

Surgical removal of spontaneous intracerebral hemorrhage may reduce secondary destruction of brain tissue. However, large surgical trials of craniotomy have not demonstrated definitive improvement in clinical outcomes. Minimally invasive surgery may limit surgical tissue injury, and recent evidence supports testing these approaches in large clinical trials.

METHODS AND DESIGN

MISTIE III is an investigator-initiated multicenter, randomized, open-label phase 3 study investigating whether minimally invasive clot evacuation with thrombolysis improves functional outcomes at 365 days compared to conservative management. Patients with supratentorial intracerebral hemorrhage clot volume ≥ 30 mL, confirmed by imaging within 24 h ofknown symptom onset,and intact brainstem reflexes were screened with a stability computed tomography scan at least 6 h after diagnostic scan. Patients who met clinical and imaging criteria (no ongoing coagulopathy; no suspicion of aneurysm, arteriovenous malformation, or any other vascular anomaly; and stable hematoma size on consecutive scans) were randomized to either minimally invasive surgery plus thrombolysis or medical therapy. The sample size of 500 was based on findings of a phase 2 study.

STUDY OUTCOMES

The primary outcome measure is dichotomized modified Rankin Scale 0-3 vs. 4-6 at 365 days adjusting for severity variables. Clinical secondary outcomes include dichotomized extended Glasgow Outcome Scale and all-cause mortality at 365 days; rate and extent of parenchymal blood clot removal; patient disposition at 365 days; efficacy at 180 days; type and intensity of ICU management; and quality of life measures. Safety was assessed at 30 days and throughout the study.

Efficacy and safety of minimally invasive surgery with thrombolysis in intracerebral haemorrhage evacuation (MISTIE III): a randomised, controlled, open-label, blinded endpoint phase 3 trial

BACKGROUND

Acute stroke due to supratentorial intracerebral haemorrhage is associated with high morbidity and mortality. Open craniotomy haematoma evacuation has not been found to have any benefit in large randomised trials. We assessed whether minimally invasive catheter evacuation followed by thrombolysis (MISTIE), with the aim of decreasing clot size to 15 mL or less, would improve functional outcome in patients with intracerebral haemorrhage.

METHODS

MISTIE III was an open-label, blinded endpoint, phase 3 trial done at 78 hospitals in the USA, Canada, Europe, Australia, and Asia. We enrolled patients aged 18 years or older with spontaneous, non-traumatic, supratentorial intracerebral haemorrhage of 30 mL or more. We used a computer-generated number sequence with a block size of four or six to centrally randomise patients to image-guided MISTIE treatment (1·0 mg alteplase every 8 h for up to nine doses) or standard medical care. Primary outcome was good functional outcome, defined as the proportion of patients who achieved a modified Rankin Scale (mRS) score of 0-3 at 365 days, adjusted for group differences in prespecified baseline covariates (stability intracerebral haemorrhage size, age, Glasgow Coma Scale, stability intraventricular haemorrhage size, and clot location). Analysis of the primary efficacy outcome was done in the modified intention-to-treat (mITT) population, which included all eligible, randomly assigned patients who were exposed to treatment. All randomly assigned patients were included in the safety analysis. This study is registered with ClinicalTrials.gov, number NCT01827046.

FINDINGS

Between Dec 30, 2013, and Aug 15, 2017, 506 patients were randomly allocated: 255 (50%) to the MISTIE group and 251 (50%) to standard medical care. 499 patients (n=250 in the MISTIE group; n=249 in the standard medical care group) received treatment and were included in the mITT analysis set. The mITT primary adjusted efficacy analysis estimated that 45% of patients in the MISTIE group and 41% patients in the standard medical care group had achieved an mRS score of 0-3 at 365 days (adjusted risk difference 4% [95% CI -4 to 12]; p=0·33). Sensitivity analyses of 365-day mRS using generalised ordered logistic regression models adjusted for baseline variables showed that the estimated odds ratios comparing MISTIE with standard medical care for mRS scores higher than 5 versus 5 or less, higher than 4 versus 4 or less, higher than 3 versus 3 or less, and higher than 2 versus 2 or less were 0·60 (p=0·03), 0·84 (p=0·42), 0·87 (p=0·49), and 0·82 (p=0·44), respectively. At 7 days, two (1%) of 255 patients in the MISTIE group and ten (4%) of 251 patients in the standard medical care group had died (p=0·02) and at 30 days, 24 (9%) patients in the MISTIE group and 37 (15%) patients in the standard medical care group had died (p=0·07). The number of patients with symptomatic bleeding and brain bacterial infections was similar between the MISTIE and standard medical care groups (six [2%] of 255 patients vs three [1%] of 251 patients; p=0·33 for symptomatic bleeding; two [1%] of 255 patients vs 0 [0%] of 251 patients; p=0·16 for brain bacterial infections). At 30 days, 76 (30%) of 255 patients in the MISTIE group and 84 (33%) of 251 patients in the standard medical care group had one or more serious adverse event, and the difference in number of serious adverse events between the groups was statistically significant (p=0·012).

INTERPRETATION

For moderate to large intracerebral haemorrhage, MISTIE did not improve the proportion of patients who achieved a good response 365 days after intracerebral haemorrhage. The procedure was safely adopted by our sample of surgeons.

FUNDING

National Institute of Neurological Disorders and Stroke and Genentech.

Cerebrospinal Fluid Leak Rate after Vestibular Schwannoma Surgery via Middle Cranial Fossa Approach

Objective  Evaluate the cerebrospinal fluid (CSF) leak rate after the middle cranial fossa (MCF) approach to vestibular schwannoma (VS) resection. Design  Retrospective case series. Setting  Quaternary referral academic center. Participants  Of 161 patients undergoing the MCF approach for a variety of skull base pathologies, 66 patients underwent this approach for VS resection between 2007 and 2017. Main Outcome Measure  Postoperative CSF leak rate. Results  There were two instances of postoperative CSF leak (3.0%). Age, gender, and BMI were not significantly associated with CSF leak. In the two cases with CSF leakage, tumors were isolated to the internal auditory canal (IAC) and both underwent gross total resection. Both CSF leaks were successfully treated with lumbar drain diversion. For the 64 cases that did not have a CSF leak, 51 were isolated to the IAC, 1 was located only in the cerebellopontine angle (CPA), and 12 were located in both the IAC and CPA. 62 patients underwent gross total resection and 2 underwent near-total resection. Mean maximal tumor diameter in the CSF leak group was 4.5 mm (range: 3-6 mm) versus 10.2 mm (range: 3-19 mm) in patients with no CSF leak ( p  = 0.03). Conclusions  The MCF approach for VS resection is a valuable technique that allows for hearing preservation and total tumor resection and can be performed with a low CSF leakage rate. This rate of CSF leak is less than the reported rates in the literature in regard to both translabyrinthine and retrosigmoid approaches.

Impact of Motor-Evoked Potential Monitoring on Facial Nerve Outcomes after Vestibular Schwannoma Resection

Objectives:

Assess the utility of intraoperative transcranial facial motor-evoked potential (FMEP) monitoring in predicting and improving facial function after vestibular schwannoma (VS) resection.

Study Design:

Retrospective chart review.

Methods:

Data were obtained from 82 consecutive VS resections meeting inclusion criteria. Sixty-two cases were performed without FMEP and 20 with FMEP. Degradation of FMEP response was defined as a final-to-baseline amplitude ratio of 0.5 or less. House-Brackmann (HB) grade was assessed preoperatively, postoperatively, at follow-up assessments, and it was compared between pre- and post-FMEP cohorts. Positive predictive value (PPV) and negative predictive value (NPV), sensitivity, and specificity of FMEP degradation in predicting facial weakness were calculated.

Results:

In the pre-FMEP group, at length of follow-up (LOF) ⩾9 months, 83.9% (52/62) of patients exhibited HB 1-2 outcome. In the post-FMEP cohort, 75.0% (15/20) exhibited HB 1-2 function at LOF ⩾9 months. There was no difference in rates of HB 1-2 outcomes between groups in the immediate postoperative period ( P = .35) or at long-term follow-up ( P = 1.0). With respect to predicting immediate postoperative facial function, FMEP demonstrated high specificity (88.9%) and moderate sensitivity (54.5%). The PPV and NPV for immediate postoperative facial function were 85.7% and 61.5%, respectively. With respect to long-term (⩾9 months LOF) facial function, intraoperative FMEP was moderately sensitive (71.4%) and highly specific (84.6%); PPV was moderate (71.4%), and NPV was high (84.6%).

Conclusions:

Intraoperative FMEP is highly specific and moderately sensitive in predicting postoperative facial function for patients undergoing VS resection, but its use may not be associated with improved facial nerve outcomes.

Level of Evidence:

4