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Nida Fatima, Victoria Y. Ding, Summer S. Han, Steven D. Chang, and Antonio Meola

OBJECTIVE

Cavernous sinus meningioma (CSM) can affect visual function and require expeditious treatment to prevent permanent visual loss. Authors of this retrospective study sought to determine the factors associated with visual functional outcomes in CSM patients treated with surgery, stereotactic radiosurgery (SRS), or stereotactic radiation therapy (SRT), alone or in combination.

METHODS

Consecutive patients with CSM who had presented at an academic tertiary care hospital from 2000 to 2018 were identified through retrospective chart review. Visual function—visual eye deficit (VED), optic disc (OD) appearance, intraocular pressure (IOP), and extraocular movement (EOM)—was assessed before and after treatment for CSM. VED with visual acuity (VA) ≤ 20/200 and visual field defect ≥ −11 dB, pale OD appearance in the ipsilateral or contralateral eye, increased ipsilateral IOP, and/or EOM restriction were defined as a poor visual functional outcome. Multivariable logistic regression was used to evaluate the associations between pretreatment visual functional assessment and posttreatment visual outcomes.

RESULTS

The study cohort included 44 patients (73% female; median age 55 years), with a median clinical follow-up of 14 months. Ipsilateral VED improved, remained stable, or worsened, respectively, in 0%, 33.4%, and 66.6% of the patients after subtotal resection (STR) alone; in 52.6%, 31.6%, and 15.8% after STR plus radiation treatment; in 28.5%, 43.0%, and 28.5% after gross-total resection (GTR) alone; and in 56.3%, 43.7%, and 0% after radiation treatment (SRS or SRT) alone. Contralateral VED remained intact in all the patients after STR alone and those with radiation treatment (SRS or SRT) alone; however, it improved, remained stable, or worsened in 10.5%, 84.2%, and 5.3% after STR plus radiation treatment and in 43.0%, 28.5%, and 28.5% after GTR alone. EOM remained intact, fully recovered, remained stable, and worsened, respectively, in 0%, 50%, 50%, and 0% of the patients after STR alone; in 36.8%, 47.4%, 15.8%, and 0% of the patients after STR with radiation treatment; in 57.1%, 0%, 28.6%, and 14.3% of the patients after GTR alone; and in 56.2%, 37.5%, 6.3%, and 0% of the patients after radiation treatment (SRS or SRT) alone.

In multivariable analyses adjusted for age, tumor volume, and treatment modality, initial ipsilateral poor VED (OR 10.1, 95% CI 1.05–97.2, p = 0.04) and initial ipsilateral pale OD appearance (OR 21.1, 95% CI 1.6–270.5, p = 0.02) were associated with poor ipsilateral VED posttreatment. Similarly, an initial pale OD appearance (OR 15.7, 95% CI 1.3–199.0, p = 0.03), initial poor VED (OR 21.7, 95% CI 1.2–398.6, p = 0.03), and a higher IOP in the ipsilateral eye (OR 55.3, 95% CI 1.7–173.9, p = 0.02) were associated with an ipsilateral pale OD appearance posttreatment. Furthermore, a higher initial ipsilateral IOP (OR 35.9, 95% CI 3.3–400.5, p = 0.004) was indicative of a higher IOP in the ipsilateral eye posttreatment. Finally, initial restricted EOM was indicative of restricted EOM posttreatment (OR 20.6, 95% CI 18.7–77.0, p = 0.02).

CONCLUSIONS

Pretreatment visual functional assessment predicts visual outcomes in patients with CSM and can be used to identify patients at greater risk for vision loss.

Free access

Yiping Li, Anadjeet Khahera, Jason Kim, Mauricio Mandel, Summer S. Han, and Gary K. Steinberg

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%.

Free access

Ephraim W. Church, Mark G. Bigder, Eric S. Sussman, Santosh E. Gummidipundi, Summer S. Han, Jeremy J. Heit, Huy M. Do, Robert L. Dodd, Michael P. Marks, and Gary K. Steinberg

OBJECTIVE

Perforator arteries, the absence of an aneurysm discrete neck, and the often-extensive nature of posterior circulation fusiform aneurysms present treatment challenges. There have been advances in microsurgical and endovascular approaches, including flow diversion, and the authors sought to review these treatments in a long-term series at their neurovascular referral center.

METHODS

The authors performed a retrospective chart review from 1990 to 2018. Primary outcomes were modified Rankin Scale (mRS) scores and Glasgow Outcome Scale (GOS) scores at follow-up. The authors also examined neurological complication rates. Using regression techniques, they reviewed independent and dependent variables, including presenting features, aneurysm location and size, surgical approach, and pretreatment and posttreatment thrombosis.

RESULTS

Eighty-four patients met the inclusion criteria. Their mean age was 53 years, and 49 (58%) were female. Forty-one (49%) patients presented with subarachnoid hemorrhage. Aneurysms were located on the vertebral artery (VA) or posterior inferior cerebellar artery (PICA) in 50 (60%) patients, basilar artery (BA) or vertebrobasilar junction (VBJ) in 22 (26%), and posterior cerebral artery (PCA) in 12 (14%). Thirty-one (37%) patients were treated with microsurgical and 53 (63%) with endovascular approaches. Six aneurysms were treated with endovascular flow diversion. The authors found moderate disability or better (mRS score ≤ 3) in 85% of the patients at a mean 14-month follow-up. The GOS score was ≥ 4 in 82% of the patients. The overall neurological complication rate was 12%. In the regression analysis, patients with VA or PICA aneurysms had better functional outcomes than the other groups (p < 0.001). Endovascular strategies were associated with better outcomes for BA-VBJ aneurysms (p < 0.01), but microsurgery was associated with better outcomes for VA-PICA and PCA aneurysms (p < 0.05). There were no other significant associations between patient, aneurysm characteristics, or treatment features and neurological complications (p > 0.05). Patients treated with flow diversion had more complications than those who underwent other endovascular and microsurgical strategies, but the difference was not significant in regression models.

CONCLUSIONS

Posterior circulation fusiform aneurysms remain a challenging aneurysm subtype, but an interdisciplinary treatment approach can result in good outcomes. While flow diversion is a useful addition to the armamentarium, traditional endovascular and microsurgical techniques continue to offer effective options.

Free access

Troels H. Nielsen, Kumar Abhinav, Eric S. Sussman, Summer S. Han, Yingjie Weng, Teresa Bell-Stephens, CNRN, Jeremy J. Heit, and Gary K. Steinberg

OBJECTIVE

The only effective treatment for ischemic moyamoya disease (iMMD) is cerebral revascularization by an extracranial to intracranial bypass. The preferred revascularization method remains controversial: direct versus indirect bypass. The purpose of this study was to test the hypothesis that method choice should be personalized based on angiographic, hemodynamic, and clinical characteristics to balance the risk of perioperative major stroke against treatment efficacy.

METHODS

Patients with iMMD were identified retrospectively from a prospectively maintained database. Those with mild to moderate internal carotid artery or M1 segment stenosis, preserved cerebrovascular reserve, intraoperative M4 segment anterograde flow ≥ 8 ml/min, or the absence of frequent and severe transient ischemic attacks (TIAs) or stroke had been assigned to indirect bypass. The criteria for direct bypass were severe ICA or M1 segment stenosis or occlusion, impaired cerebrovascular reserve or steal phenomenon, intraoperative M4 segment retrograde flow or anterograde flow < 8 ml/min, and the presence of frequent and severe TIAs or clinical strokes. The primary study endpoint was MRI-confirmed symptomatic stroke ≤ 7 days postoperatively resulting in a decline in the modified Rankin Scale (mRS) score from preoperatively to 6 months postoperatively. As a secondary endpoint, the authors assessed 6-month postoperative DSA-demonstrated revascularization, which was classified as < 1/3, 1/3–2/3, or > 2/3 of the middle cerebral artery territory.

RESULTS

One hundred thirty-eight patients with iMMD affecting 195 hemispheres revascularized in the period from March 2016 to June 2018 were included in this analysis. One hundred thirty-three hemispheres were revascularized with direct bypass and 62 with indirect bypass. The perioperative stroke rate was 4.7% and 6.8% in the direct and indirect groups, respectively (p = 0.36). Degree of revascularization was higher in the direct bypass group (p = 0.03). The proportion of patients improving to an mRS score 0–1 (from preoperatively to 6 months postoperatively) tended to be higher in the direct bypass group, although the difference between the two bypass groups was not statistically significant (p = 0.27).

CONCLUSIONS

The selective use of an indirect bypass procedure for iMMD did not decrease the perioperative stroke rate. Direct bypass provided a significantly higher degree of revascularization. The authors conclude that direct bypass is the treatment of choice for iMMD.

Restricted access

Ephraim W. Church, Rabia Qaiser, Teresa E. Bell-Stephens, Mark G. Bigder, Eric K. Chow, Summer S. Han, Yasser Y. El-Sayed, and Gary K. Steinberg

OBJECTIVE

Moyamoya disease (MMD) disproportionately affects young to middle-aged women. The main treatment for this challenging disease is cerebral bypass surgery. Vascular neurosurgeons often need to counsel women regarding pregnancy following bypass for MMD, but there is a paucity of data. The authors set out to examine neurological and obstetric outcomes in an extensive cohort of MMD patients who had pregnancies following cerebral revascularization at the Stanford Medical Center.

METHODS

The authors identified all patients at their institution who underwent cerebral bypass for MMD from 1990 through 2018 and who later became pregnant. Some of these patients also had pregnancies prior to undergoing bypass surgery, and the authors examined these pregnancies as well. They performed a chart review and brief telephone survey to identify obstetric complications, transient ischemic attacks (TIAs), and strokes. Neurological and obstetric outcomes were compared to published rates. They also compared pre- and post-bypass pregnancy complication rates using logistic regression techniques.

RESULTS

There were 71 pregnancies among 56 women whose mean age was 30.5 years. Among 59 post-bypass pregnancies, there were 5 (8%) perinatal TIAs. There were no MRI-confirmed strokes or strokes with residual deficits. Among 12 pre-bypass pregnancies, there were 3 (25%) TIAs and 2 (17%) MRI-confirmed strokes. There were no hemorrhagic complications in either group. In the generalized estimating equations analysis, performing cerebral revascularization prior to pregnancy versus after pregnancy was associated with lower odds of perinatal stroke or TIA (OR 0.15, p = 0.0061). Nine pregnancies (13%) were complicated by preeclampsia, and there was one (1%) instance of eclampsia. The overall rate of cesarean delivery was 39%. There were 2 miscarriages, both occurring in the first trimester. There were no maternal deaths.

CONCLUSIONS

The authors present neurological and obstetric outcomes data in a large cohort of MMD patients. These data indicate that post-bypass pregnancy is accompanied by low complication rates. There were no ischemic or hemorrhagic strokes among post-bypass pregnant MMD patients. The rate of obstetric complications was low overall. The authors recommend close collaboration between the vascular neurosurgeon and the obstetrician regarding medical management, including blood pressure goals and continuation of low-dose aspirin.

Free access

Mark Bigder, Omar Choudhri, Mihir Gupta, Santosh Gummidipundi, Summer S. Han, Ephraim W. Church, Steven D. Chang, Richard P. Levy, Huy M. Do, Michael P. Marks, and Gary K. Steinberg

OBJECTIVE

Microsurgical resection of arteriovenous malformations (AVMs) can be aided by staged treatment consisting of stereotactic radiosurgery followed by resection in a delayed fashion. This approach is particularly useful for high Spetzler-Martin (SM) grade lesions because radiosurgery can reduce flow through the AVM, downgrade the SM rating, and induce histopathological changes that additively render the AVM more manageable for resection. The authors present their 28-year experience in managing AVMs with adjunctive radiosurgery followed by resection.

METHODS

The authors retrospectively reviewed records of patients treated for cerebral AVMs at their institution between January 1990 and August 2019. All patients who underwent stereotactic radiosurgery (with or without embolization), followed by resection, were included in the study. Of 1245 patients, 95 met the eligibility criteria. Univariate and multivariate regression analyses were performed to assess relationships between key variables and clinical outcomes.

RESULTS

The majority of lesions treated (53.9%) were high grade (SM grade IV–V), 31.5% were intermediate (SM grade III), and 16.6% were low grade (SM grade I–II). Hemorrhage was the initial presenting sign in half of all patients (49.5%). Complete resection was achieved among 84% of patients, whereas 16% had partial resection, the majority of whom received additional radiosurgery. Modified Rankin Scale (mRS) scores of 0–2 were achieved in 79.8% of patients, and 20.2% had poor (mRS scores 3–6) outcomes. Improved (44.8%) or stable (19%) mRS scores were observed among 63.8% of patients, whereas 36.2% had a decline in mRS scores. This includes 22 patients (23.4%) with AVM hemorrhage and 6 deaths (6.7%) outside the perioperative period but prior to AVM obliteration.

CONCLUSIONS

Stereotactic radiosurgery is a useful adjunct in the presurgical management of cerebral AVMs. Multimodal therapy allowed for high rates of AVM obliteration and acceptable morbidity rates, despite the predominance of high-grade lesions in this series of patients.

Free access

Michael C. Jin, Jonathon J. Parker, Laura M. Prolo, Adela Wu, Casey H. Halpern, Gordon Li, John K. Ratliff, Summer S. Han, Stephen L. Skirboll, and Gerald A. Grant

OBJECTIVE

The natural history of seizure risk after brain tumor resection is not well understood. Identifying seizure-naive patients at highest risk for postoperative seizure events remains a clinical need. In this study, the authors sought to develop a predictive modeling strategy for anticipating postcraniotomy seizures after brain tumor resection.

METHODS

The IBM Watson Health MarketScan Claims Database was canvassed for antiepileptic drug (AED)– and seizure-naive patients who underwent brain tumor resection (2007–2016). The primary event of interest was short-term seizure risk (within 90 days postdischarge). The secondary event of interest was long-term seizure risk during the follow-up period. To model early-onset and long-term postdischarge seizure risk, a penalized logistic regression classifier and multivariable Cox regression model, respectively, were built, which integrated patient-, tumor-, and hospitalization-specific features. To compare empirical seizure rates, equally sized cohort tertiles were created and labeled as low risk, medium risk, and high risk.

RESULTS

Of 5470 patients, 983 (18.0%) had a postdischarge-coded seizure event. The integrated binary classification approach for predicting early-onset seizures outperformed models using feature subsets (area under the curve [AUC] = 0.751, hospitalization features only AUC = 0.667, patient features only AUC = 0.603, and tumor features only AUC = 0.694). Held-out validation patient cases that were predicted by the integrated model to have elevated short-term risk more frequently developed seizures within 90 days of discharge (24.1% high risk vs 3.8% low risk, p < 0.001). Compared with those in the low-risk tertile by the long-term seizure risk model, patients in the medium-risk and high-risk tertiles had 2.13 (95% CI 1.45–3.11) and 6.24 (95% CI 4.40–8.84) times higher long-term risk for postdischarge seizures. Only patients predicted as high risk developed status epilepticus within 90 days of discharge (1.7% high risk vs 0% low risk, p = 0.003).

CONCLUSIONS

The authors have presented a risk-stratified model that accurately predicted short- and long-term seizure risk in patients who underwent brain tumor resection, which may be used to stratify future study of postoperative AED prophylaxis in highest-risk patient subpopulations.

Restricted access

Kelly B. Mahaney, Chandana Buddhala, Mounica Paturu, Diego M. Morales, Christopher D. Smyser, David D. Limbrick Jr., Santosh E. Gummidipundi, Summer S. Han, and Jennifer M. Strahle

OBJECTIVE

Posthemorrhagic hydrocephalus (PHH) following preterm intraventricular hemorrhage (IVH) is among the most severe sequelae of extreme prematurity and a significant contributor to preterm morbidity and mortality. The authors have previously shown hemoglobin and ferritin to be elevated in the lumbar puncture cerebrospinal fluid (CSF) of neonates with PHH. Herein, they evaluated CSF from serial ventricular taps to determine whether neonates with PHH following severe initial ventriculomegaly had higher initial levels and prolonged clearance of CSF hemoglobin and hemoglobin degradation products compared to those in neonates with PHH following moderate initial ventriculomegaly.

METHODS

In this observational cohort study, CSF samples were obtained from serial ventricular taps in premature neonates with severe IVH and subsequent PHH. CSF hemoglobin, ferritin, total iron, total bilirubin, and total protein were quantified using ELISA. Ventriculomegaly on cranial imaging was assessed using the frontal occipital horn ratio (FOHR) and was categorized as severe (FOHR > 0.6) or moderate (FOHR ≤ 0.6).

RESULTS

Ventricular tap CSF hemoglobin (mean) and ferritin (initial and mean) were higher in neonates with severe versus moderate initial ventriculomegaly. CSF hemoglobin, ferritin, total iron, total bilirubin, and total protein decreased in a nonlinear fashion over the weeks following severe IVH. Significantly higher levels of CSF ferritin and total iron were observed in the early weeks following IVH in neonates with severe initial ventriculomegaly than in those with initial moderate ventriculomegaly.

CONCLUSIONS

Among preterm neonates with PHH following severe IVH, elevated CSF hemoglobin, ferritin, and iron were associated with more severe early ventricular enlargement (FOHR > 0.6 vs ≤ 0.6 at first ventricular tap).