Hemorrhage risk, surgical management, and functional outcome of brainstem cavernous malformations

Natural history, management, and outcomes of cerebellar cavernous malformations: A retrospective study of 130 patients

OBJECTIVE

Data on the natural history and management of cerebellar cavernous malformations (CMs) is limited. This study aims to identify factors associated with hemorrhage risk, assess management strategies, and compare outcomes between conservative and surgical management in patients with cerebellar CMs.

METHODS

We retrospectively reviewed 130 patients with cerebellar CMs treated at our center (1990-2023). Data on clinical presentation, lesion characteristics, management strategies, and outcomes were analyzed. Annual hemorrhage risk was calculated. Surgical outcomes were assessed based on the persistence of CM-related symptoms and the presence of postoperative complications. Statistical analyses identified factors associated with hemorrhage, symptomatic presentation, and surgical outcomes.

RESULTS

Of 130 patients (53.8% female; median age of 48.5 years (IQR: 26.75)), 41 (31.5%) presented with hemorrhage, and 20 (15.4%) had focal neurological deficits. Median lesion size measured 12 mm (IQR 8 mm) in size and were primarily located in the hemispheres (n = 89, 68.5%), with fewer in the vermis (n = 21, 16.2%), peduncle (n = 20, 15.4%), and dentate nucleus (n = 9, 6.9%). The annual hemorrhage risk for incidental lesions was 1.19%, while rehemorrhage risk for initially hemorrhagic lesions was 8.35%. Surgery was performed in 31 patients (23.8%), mostly for hemorrhage (n = 15, 48.4%) or cerebellar symptoms (n = 7, 22.6%). Postoperative complications were reported in three patients. At a median follow-up of 1.11 years (IQR 5.15 years), 22 patients (18.2%) had persistent symptoms, two developed new symptoms, and two experienced worsening symptoms from hypertrophic olivary degeneration. There was no CM- related mortality, and only one patient experienced moderate CM-related disability (mRS = 3).

CONCLUSIONS

Cerebellar CMs generally have a benign course with hemorrhage risks compared to supratentorial and brainstem lesions. Conservative management is recommended for incidental lesions, while surgery should be reserved for symptomatic, accessible cases.

Surgical management of pontine brainstem cavernous malformations: A systematic review Emphasizing safe entry zones and clinical outcomes

OBJECTIVE

Safe entry zones (SEZs) have emerged as important corridors for accessing brainstem cavernous malformations (BSCM) while minimizing morbidity. This systematic review and meta-analysis aims to provide a comprehensive analysis of the surgical management of pontine BSCM via SEZs.

METHODS

A systematic literature search was performed in PubMed for articles reporting on the surgical management of pontine BSCM via SEZ. Data were extracted on patient demographics, clinical presentation, BSCM characteristics, surgical approach, use of SEZs, and clinical outcomes.

RESULTS

Fifteen studies with a total of 78 patients were included. The cohort was 62.8 % female with an average age of 37.62 ± 14.7 years. The most common presenting symptoms varied based on BSCM location within the pons. The two most common BSCM locations were peritrigeminal (24.4 %) and middle peduncle (10.3 %). The most frequently used surgical approach was the retrosigmoid approach (41.0 %), and the most commonly utilized SEZ was the lateral pontine zone (52.2 %). Gross total resection was achieved in 69.2 % of cases. Good clinical outcome (follow-up mRS < 2) was observed in 64.1 % of patients, with clinical deterioration observed in 7.7 %.

CONCLUSION

Surgical resection of pontine BSCM can be performed with acceptable morbidity and mortality rates when utilizing SEZs and careful preoperative planning. The lateral pontine, supratrigeminal, and peritrigeminal SEZs are associated with high rates of complete resection and improved neurological outcomes. Future studies with standardized reporting and longer follow-ups are needed to further refine surgical techniques and patient selection.

Diffusion tensor imaging with tractography in surgical resection of brainstem cavernous malformations: a systematic review and meta-analysis

Brainstem cavernous malformations are benign subset of cerebral cavernous malformations, which need a special intervention owing to being vital and complex. The diffusion tensor imaging technique, a well-recognized neuroimaging tool, can visualize the white matter tracts and their surroundings and provide promising surgical outcomes. This systematic review and meta-analysis evaluated the effect of preoperative diffusion tensor imaging in patients undergoing surgical resection of brainstem cavernous malformations. Five databases, including PubMed, Scopus, Web of Science, Cochrane Library, and Google Scholar, were searched using a comprehensive search strategy to find any article matching our inclusion criteria. We used Comprehensive Meta-Analysis (CMA) software to analyze the collected data, get the evidence, and report the results as event rate (ER), with their 95% confidence interval (CI). Twenty-eight studies involving 467 patients matched our criteria and 19 studies entered the analysis. Our analysis showed that, in patients undergoing surgical resection of brainstem cavernous malformations assisted by preoperative diffusion tensor imaging, 82.21% achieved total resection. About 12.4% of patients achieved partial resection, 65.65% improved, 8.07% worsened, 25.04% showed no change, 3.59% experienced postoperative re-bleeding, and 0.87% died. The utilization of preoperative diffusion tensor imaging significantly increased the proportion of improved patients and decreased the proportion of worsened patients. However, further controlled research is needed to draw a definite conclusion about the usefulness of its role.

Identifying potential (re)hemorrhage among sporadic cerebral cavernous malformations using machine learning

The (re)hemorrhage in patients with sporadic cerebral cavernous malformations (CCM) was the primary aim for CCM management. However, accurately identifying the potential (re)hemorrhage among sporadic CCM patients in advance remains a challenge. This study aims to develop machine learning models to detect potential (re)hemorrhage in sporadic CCM patients. This study was based on a dataset of 731 sporadic CCM patients in open data platform Dryad. Sporadic CCM patients were followed up 5 years from January 2003 to December 2018. Support vector machine (SVM), stacked generalization, and extreme gradient boosting (XGBoost) were used to construct models. The performance of models was evaluated by area under receiver operating characteristic curves (AUROC), area under the precision-recall curve (PR-AUC) and other metrics. A total of 517 patients with sporadic CCM were included (330 female [63.8%], mean [SD] age at diagnosis, 42.1 [15.5] years). 76 (re)hemorrhage (14.7%) occurred during follow-up. Among 3 machine learning models, XGBoost model yielded the highest mean (SD) AUROC (0.87 [0.06]) in cross-validation. The top 4 features of XGBoost model were ranked with SHAP (SHapley Additive exPlanations). All-Elements XGBoost model achieved an AUROCs of 0.84 and PR-AUC of 0.49 in testing set, with a sensitivity of 0.86 and a specificity of 0.76. Importantly, 4-Elements XGBoost model developed using top 4 features got a AUROCs of 0.83 and PR-AUC of 0.40, a sensitivity of 0.79, and a specificity of 0.72 in testing set. Two machine learning-based models achieved accurate performance in identifying potential (re)hemorrhages within 5 years in sporadic CCM patients. These models may provide insights for clinical decision-making.

Long-term functional outcomes and complications of microsurgical resection of brainstem cavernous malformations: a systematic review and meta-analysis

Brainstem cavernous malformations (CMs) encompass up to 20% of all intracranial CMs and are considered more aggressive than cerebral CMs because of their high annual bleeding rates. Microsurgical resection remains the primary treatment modality for CMs, but long-term functional outcomes and complications are heterogenous in the literature. The authors performed a systematic review on brainstem CMs in 4 databases: PubMed, EMBASE, Cochrane library, and Google Scholar. We included studies that reported on the long-term functional outcomes and complications of brainstem CMs microsurgical resection. A meta-analysis was performed and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The search yielded 4781 results, of which 19 studies met our inclusion criteria. Microsurgery was performed on 940 patients (mean age 35 years, 46.9% females). Most of the brainstem CMs were located in the pons (n = 475). The pooled proportions of improved, stable, and worsened functional outcomes after microsurgical resection of brainstem CMs were 56.7% (95% CI 48.4-64.6), 28.6% (95% CI 22.4-35.7), and 12.6% (95% CI 9.6-16.2), respectively. CMs located in the medulla were significantly (p = 0.003) associated with a higher proportion of improved outcome compared with those in the pons and midbrain. Complete resection was achieved in 93.3% (95% CI 89.8-95.7). The immediate postoperative complication rate was 37.2% (95% CI 29.3-45.9), with new-onset cranial nerve deficit being the most common complication. The permanent morbidity rate was 17.3% (95% CI 10.5-27.1), with a low mortality rate of 1% from the compiled study population during a mean follow-up of 58 months. Our analysis indicates that microsurgical resection of brainstem CMs can result in favorable long-term functional outcomes with transient complications in the majority of patients. Complete microsurgical resection of the CM is associated with a lower incidence of CM hemorrhage and the morbidity related to it.

Cerebral cavernous malformation: Management, outcomes, and surveillance strategies - A single centre retrospective cohort study

BACKGROUND

Cerebral cavernous malformations (CCM) may undergo a period of clinical and/or radiographical surveillance that precedes or follows definitive treatment. There are no international guidelines on the optimal surveillance strategy. This study describes the surveillance strategies at our centre and explore the related clinical outcomes.

METHODS

We performed a retrospective study of adult patients with CCMs referred to a neurovascular service over an 8-year period, to determine the frequency and type of surveillance, intervention, and explore the associated outcomes. We report our findings adhering to STROBE guidelines.

RESULTS

133 patients (Male:Female 73:60; men age 42 years; range 12-82) were included. CCMs were identified in patients first presenting with symptomatic intracerebral haemorrhage (42.11%); headache, focal neurological deficit, or seizure without haemorrhage (41.35%); or, as an incidental finding (16.54%). The most common CCM location was supratentorial (59.40%), followed by brain stem (21.80%), cerebellum (10.53%) and basal ganglia (6.02%). Of the 133 patients, 77 patients (57.89%) were managed conservatively, 49 patients (36.84%) were managed by surgical resection alone, and seven patients (5.26%) were managed with stereotactic radiosurgery (SRS). Patients follow-up had a mean duration of 65.94 months, and varied widely (SD = 52.59; range 0-265), for a total of 730.83 person-years of follow up. During surveillance, 16 patients suffered an ICH equating to a bleeding rate of 2.19 per 100 patient years. CCMs that increased in size had a higher bleeding rate (p = 8.58 ×10^-4). There were 8 (6.02%) cases where routine clinic review or MRI resulted in a change in management.

CONCLUSIONS

Our single centre retrospective study supports existing literature relating to presentation and sequalae of CCM, with an increase in CCM size being associated with higher rates of detected bleeding. There remains heterogeneity, even within a single centre, on the frequency and modality of surveillance. Further, there are no international guidelines or high-quality data that recommends the optimal duration and frequency of surveillance, and its effect on clinical outcomes. This is a future research direction.

Nomogram for predicting an individual prospective hemorrhage risk in untreated brainstem cavernous malformations

OBJECTIVE

In this study, the authors aimed to create a nomogram for precisely predicting the 5-year prospective hemorrhage risk in brainstem cavernous malformations (BSCMs).

METHODS

Patients with confirmed BSCMs in a single-center prospective observational series from January 2012 to December 2016 were included in the present study for nomogram building and validation. The concordance index (C-index), calibration curves, and decision curve analysis were used to evaluate the predictive accuracy, discriminative ability, and clinical usefulness of the nomogram. Then, a nomogram-based risk stratification model for untreated BSCMs was developed.

RESULTS

In total, 600 patients were included in the study; 417 patients who had been enrolled before July 2015 were divided into the training and validation cohorts, and 183 subsequently enrolled patients were used as the external validation cohort. By applying a backward stepwise procedure in the multivariable Cox model, variables, including prior hemorrhage (HR 1.69), hemorrhage on admission (HR 3.33), lesion size > 1.5 cm (HR 1.84), lesion depth (HR 2.35), crossing the axial midpoint (HR 1.94), and developmental venous anomaly (HR 2.62), were incorporated to develop a nomogram. The Harrell C-index values for a 5-year prospective hemorrhage were 0.752 (95% CI 0.687–0.816), 0.801 (95% CI 0.665–0.936), and 0.758 (95% CI 0.674–0.842) in the training, internal validation, and external validation cohorts, respectively. The nomogram performed well in terms of consistency between prediction and actual observation according to the calibration curve. The patients could be classified into three distinct (low, medium, and high) risk groups using the final score of this nomogram.

CONCLUSIONS

Independent predictors of the 5-year hemorrhage risk in untreated BSCMs were selected to create the first nomogram for predicting individual prospective hemorrhage. The nomogram was able to stratify patients into different risk groups and assist in clinical decision-making.

Five-year symptomatic hemorrhage risk of untreated brainstem cavernous malformations in a prospective cohort

Hemorrhage of brainstem cavernous malformation (CM) would cause various symptoms and severe disability. The study aimed to elaborate on the 5-year actuarial cumulative hazard of symptomatic hemorrhage. Patients diagnosed in our institute between 2009 and 2013 were prospectively registered. All clinical data were obtained, follow-up was performed, and risk factors were evaluated. Four hundred sixty-eight patients (217 female, 46.4%) were included in the study with a median follow-up duration of 79.0 months. A total of 137 prospective hemorrhages occurred in 107 patients (22.9%) during 1854.0 patient-years. Multivariate Cox analysis found age ≥ 55 years (hazard ratio (HR) 2.166, p = 0.002), DVA (HR 1.576, p = 0.026), superficial-seated location (HR 1.530, p = 0.047), and hemorrhage on admission (HR 2.419, p = 0.026) as independent risk factors for hemorrhage. The 5-year cumulative hazard of hemorrhage was 30.8% for the overall cohort, 47.8% for 60 patients with age ≥ 55 years, 43.7% for 146 patients with DVA, 37.9% for 272 patients with superficial-seated lesions, and 37.2% for 341 patients with hemorrhage on admission. As a stratified analysis, within subcohort of 341 patients with a hemorrhagic presentation, age ≥ 55 years (HR 3.005, p < 0.001), DVA (HR 1.801, p = 0.010), and superficial-seated location (HR 2.276, p = 0.001) remained independently significant. The 5-year cumulative hazard of hemorrhage was 52.0% for 119 patients with both DVA and hemorrhagic presentation. The 5-year cumulative hemorrhagic risk was 30.8% and was higher in subgroups if harboring risk factors that helped to predict potential hemorrhagic candidates and were useful for treatment decision-making.Clinical Trial Registration-URL: http://www.chictr.org.cn Unique identifier: ChiCTR-POC-17011575.

Laser Interstitial Thermal Therapy for Cavernous Malformations: A Systematic Review

Background

Microsurgical resection of intracranial cavernous malformations (CM) is regarded as the standard treatment, but in recent years, there has been a trend toward minimally invasive procedures like ablation of such lesions by using laser interstitial thermal therapy (LITT).

Methods

A systematic search using keywords ‘laser interstitial thermal therapy’ OR ‘LITT’ AND ‘cavernoma’ OR ‘cavernous angiomas’ OR ‘cavernous malformations’ was conducted in MEDLINE (PubMed), Scopus, Embase, and Cochrane electronic bibliographic databases and studies reporting the outcome of LITT procedure on intracranial CM were included. The demographic data, symptoms of patients, location and size of the lesion, and surgical outcome were extracted from the articles.

Result

Six studies, reporting the outcome of 33 patients were included in this review. In 26 patients, CM was identified as the epileptogenic foci and in others, CM was the source of headache or focal neurological deficits. LITT led to a satisfactory outcome in all patients except for three who achieved improvement in symptoms after the open resection of the lesion. Most of the post-operative complications were transient and resolved at the time of the last follow up. Cyst formation at the previous ablated CM site was reported as the long-term complication of LITT in one case.

Conclusion

LITT can provide a comparable outcome to the open resection of CMs, by having less invasiveness, even in deep and eloquent area lesions, and complications that are often temporary and disappear gradually. However, technical issues, such as thermal monitoring during the procedure, are considered a challenge for this procedure in CMs. Further studies with a larger population are needed to report this method's long-term outcome and complications on CMs.

Brainstem Cavernous Malformations Management: Microsurgery vs. Radiosurgery, a Meta-Analysis

Given the rareness of available data, we performed a systematic review and meta-analysis on therapeutic strategy microsurgical resection and stereotactic radiosurgery (SRS) for brainstem cavernous malformations (BSCMs) and assessed mortality, permanent neurological deficits (PNDs), rebleeding rate, and patients who require reintervention to elucidate the benefits of each treatment modality. Preferred reporting items for systematic reviews and meta-analyses (PRISMA) were used for protocol development and manuscript preparation. After applying all inclusion and exclusion criteria, six remaining articles were included in the final manuscript pool. In total, this meta-analysis included 396 patients, among them 168 patients underwent microsurgical treatment and 228 underwent SRS. Findings of the present meta-analysis suggest that regarding the total group of patients, in terms of mortality, late rebleeding rate, and PNDs, there was no superiority of the one method over the other. Applying the leave-one-out method to our study suggests that with low robust of the results for the bleeding rate and patients who require reintervention outcome factor, there was no statistical difference among the surgical and SRS treatment. Microsurgical treatment of BSCMs immediately eliminates the risk of rehemorrhage; however, it requires complete excision of the lesion and it is associated with a similar rate of PNDs compared with SRS management. Apparently, SRS of BSCMs causes a marked reduction in the risk of rebleeding 2 years after treatment, but when compared with the surgical treatment, there was not any remarkable difference.

The BSCM score: a guideline for surgical decision-making for brainstem cavernous malformations

Microsurgical resection of brainstem cavernous malformations (BSCMs) can be performed today with acceptable morbidity and mortality. However, in this highly eloquent location, the indication for surgery remains challenging. We aimed to elaborate a score system that may help clinicians with their choice of treatment in patients with BSCMs in this study. A single-center series of 88 consecutive BSCMs patients with 272 follow-up visits were included in this study. Univariable and multivariable generalized estimating equations (GEE) were constructed to identify the association of variables with treatment decisions. A score scale assigned points for variables that significantly contributed to surgical decision-making. Surgical treatment was recommended in 37 instances, while conservative treatment was proposed in 235 instances. The mean follow-up duration was 50.4 months, and the mean age at decision-making was 45.9 years. The mean BSCMs size was 14.3 ml. In the multivariable GEE model, patient age, lesion size, hemorrhagic event(s), mRS, and axial location were identified as significant factors for determining treatment options. With this proposed score scale (grades 0–XII), non-surgery was the first option at grades 0–III. The crossover point between surgery and non-surgery recommendations lay between grades V and VI while surgical treatment was found in favor at grades VII–X. In conclusion, the proposed BSCM operating score is a clinician-friendly tool, which may help neurosurgeons decide on the treatment for patients with BSCMs.

The benefit and outcome prediction of acute surgery for hemorrhagic brainstem cavernous malformation with impending respiratory failure

OBJECTIVES

Impending respiratory failure is catastrophic neurological deterioration caused by repeated c of a brainstem cavernous malformation (BSCM). The benefit and outcome prediction of acute surgery for this fatal condition is rarely reported. In this study, the authors reported a case series of acute surgical treatment (≤3 weeks after the last hemorrhagic episode) for the BSCM with impending respiratory failure and reviewed literature over the past 20 years.

MATERIALS AND METHODS

Clinical and outcome data from 6 consecutive acute surgically-treated BSCM patients were analyzed. Intracerebral hemorrhage (ICH) scores, primary pontine hemorrhage (PPH) scores, and Lawton's BSCM grading were applied for surgical outcome prediction. Ten related articles were included for the literature review.

RESULTS

There were three men and three women, with a mean age of 32.2 ± 9.3 years (range 15-45 years). The BSCMs were located at the pons in 5 cases and the medulla in 1 case. The ICH score was 1-2 in all cases, while the PPH score was 0 in all pontine BSCMs. For Lawton's BSCM grading, 3 cases were grade 2, 2 cases were grade 3, and 1 case was grade 1. All patients achieved spontaneous respiratory dysfunction relief postoperatively and significantly improved at follow-up (mean 4.47 ± 0.24 years;range4.0-5.6 years).

CONCLUSIONS

Repeated hemorrhagic BSCM with impending respiratory failure can benefit from acute surgical treatment. The ICH score, PPH score, and Lawton's BSCM grading are promisingly useful tools for fast and efficient surgical outcome prediction.

Endoscopic Endonasal Transclival Approach to Ventral Pontine Cavernous Malformation: Case Report

Ventral medial pontine cavernous malformations are challenging due to the location in eloquent tissue, surrounding critical anatomy, and potential symptomatic bleeding. Conventional approaches, such as anterolateral, lateral and dorsal approach, are associated with high risk of deleterious consequences due to excessive traction and damage to the surrounding tissues. The authors present an endoscopic endonasal approach for the resection of midline ventral pontine cavernous malformations, which follows principles of optimal access to brainstem cavernous malformations as the “two-point method.” No CSF leak or any other complications are obtained. The successful outcomes indicate that an individualized approach should be chosen before the surgery for brainstem cavernous malformations. With the advance of techniques, endoscopic endonasal approach could provide the most direct route to ventral pontine lesions with safety and efficiency.

Endoscopic endonasal surgery to treat intrinsic brainstem lesions: correlation between anatomy and surgery

OBJECTIVE

The endoscopic endonasal approach (EEA) has been proposed as an alternative in the surgical removal of ventral brainstem lesions. However, the feasibility and limitations of this approach to treat such pathologies are still poorly understood. This study aimed to report our experience in five consecutive cases of intrinsic brainstem lesions that were managed via an EEA, as well as the specific anatomy of each case.

METHODS

All patients were treated in a single center by a multidisciplinary surgical team between 2015 and 2019. Before surgery, a dedicated anatomical analysis of the brainstem safe entry zone was performed, and proper surgical planning was carried out. Neurophysiological monitoring was used in all cases. Anatomical dissections were performed in three human cadaveric heads using 0° and 30° endoscopes, and specific 3D reconstructions were executed using Amira 3D software.

RESULTS

All lesions were located at the level of the ventral brainstem. Specifically, one mesencephalic cavernoma, two pontine ca- vernomas, one pontine gliomas, and one medullary diffuse midline glioma were reported. Cerebrospinal fluid leak was the major complication that occurred in one case (medullary diffuse midline glioma). From an anatomical standpoint, three main safe entry zones were used, namely the anterior mesencephalic zone (AMZ), the peritrigeminal zone (PTZ, used in two cases), and the olivar zone (OZ). Reviewing the literature, 17 cases of various brainstem lesions treated using an EEA were found.

CONCLUSIONS

To our knowledge, this was the first preliminary clinical series of intrinsic brainstem lesions treated via an EEA presented in the literature. The EEA can be considered a valid surgical alternative to traditional transcranial approaches to treat selected intra-axial brainstem lesions located at the level of the ventral brainstem. To achieve good results, surgery must involve comprehensive anatomical knowledge, meticulous preoperative surgical planning, and intraoperative neurophysiological moni- toring.

Holmes tremor in a monocentric series of resected brainstem cavernomas

OBJECT

Several scientific papers report clinical symptoms, indications, complications and outcomes of brainstem cavernous malformation (BSCM) surgery without reporting on the occurrence of postoperative Holmes tremor (HT). Our purpose is to report our experience with HT in a monocentric series of resected brainstem cavernomas.

METHODS

We reviewed all the BSCM surgical records between 2002 and 2018 at Saint-Luc University Hospital's Department of Neurosurgery, Brussels and selected patients developing HT postoperatively. Patients' demographics, symptoms, pre- and postoperative imaging, recurrence and complications were analysed. A PubMed literature review was performed to compare our results with those in the existing literature.

RESULTS

In a total series of 18 resected BSCM, 5 patients: 1 male and 4 females, with a median age of 51 years (range 29-59 years), developed HT. The median preoperative mRS score was 2 (range 1-4). GTR was achieved in all patients without surgery-related death. BSCM were located in the mesencephalon in 4 patients (80%) who developed HT. Tremor was noticed between ten days and one year after surgery. One patient saw significant improvements to the point of stopping treatment. The median follow-up period was 2 years (range 1-14 years). At the last follow-up, 40% of our patients showed a worse mRS score, 40% stayed unchanged, and 20% improved.

CONCLUSION

We are reporting an original single-center series of patients suffering from HT after BSCM surgery. The risk for HT after surgery is significant for midbrain BSCM. A spontaneous favorable evolution is possible.

Neurological outcomes of untreated brainstem cavernous malformations in a prospective observational cohort and literature review

Background

Haemorrhages of brainstem cavernous malformations (CMs) can lead to neurological deficits, the natural history of which is uncertain. The study aimed to evaluate the neurological outcomes of untreated brainstem CMs and to identify the adverse factors associated with worsened outcomes.

Methods

From 2009 to 2015, 698 patients (321 women) with brainstem CMs were entered into the prospective cohort after excluding patients lost to follow-up (n=43). All patients were registered, clinical data were collected and scheduled follow-up was performed.

Results

After a median follow-up of 60.9 months, prospective haemorrhages occurred in 167 patients (23.9%). The mean modified Rankin Scale scores at enrolment and at censoring time were 1.6 and 1.2. Neurological status was improved, unchanged and worsened in 334 (47.9%), 293 (42.0%) and 71 (10.2%) patients, respectively; 233 (33.4%) recovered to normal levels. Lesions crossing the axial midpoint (relative risk (RR) 2.325, p=0.003) and developmental venous anomaly (DVA) (RR 1.776, p=0.036) were independently significantly related to worsened outcomes. The percentage of worsened outcomes was 5.3% (18 of 337) in low-risk patients (neither DVA nor crossing the axial point) and increased to 26.0% (13 of 50) in high-risk patients (with both DVA and crossing the axial point). The percentage of worsened outcomes significantly increased as the number of prospective haemorrhages increased (from 1.5% (8 of 531, if 0 prospective ictus) to 37.5% (48 of 128, if 1 ictus) and 38.5% (15 of 39, if >1 ictus)).

Conclusions

The neurological outcomes of untreated brainstem CMs were improved/unchanged in majority of patients (89.8%) with a fatality rate of 1.7% in our cohort, which seemed to be favourable. Radiological features significantly predicted worsened outcomes. Our results provide evidence for clinical consultation and individualised treatment. The referral bias of our cohort was underlined.

Natural history of brainstem cavernous malformations: prospective hemorrhage rate and adverse factors in a consecutive prospective cohort

OBJECTIVE

Given the paucity of data on the natural history of brainstem cavernous malformations (CMs), the authors aimed to evaluate the annual hemorrhage rate and hemorrhagic risk of brainstem CMs.

METHODS

Nine hundred seventy-nine patients diagnosed with brainstem CMs were referred to Beijing Tiantan Hospital from 2006 to 2015; 224 patients were excluded according to exclusion criteria, and 47 patients were lost to follow-up. Thus, this prospective observational cohort included 708 cases (324 females). All patients were registered, clinical data were recorded, and follow-up was completed.

RESULTS

Six hundred ninety (97.5%) of the 708 patients had a prior hemorrhage, 514 (72.6%) had hemorrhagic presentation, and developmental venous anomaly (DVA) was observed in 241 cases (34.0%). Two hundred thirty-seven prospective hemorrhages occurred in 175 patients (24.7%) during 3400.2 total patient-years, yielding a prospective annual hemorrhage rate of 7.0% (95% CI 6.2%-7.9%), which decreased to 4.7% after the 1st year. Multivariate Cox regression analysis after adjusting for sex and age identified hemorrhagic presentation (HR 1.574, p = 0.022), DVA (HR 1.678, p = 0.001), mRS score ≥ 2 on admission (HR 1.379, p = 0.044), lesion size > 1.5 cm (HR 1.458, p = 0.026), crossing the axial midpoint (HR 1.446, p = 0.029), and superficially seated location (HR 1.307, p = 0.025) as independent adverse factors for prospective hemorrhage, but history of prior hemorrhage was not significant. The annual hemorrhage rates were 8.3% and 4.3% in patients with and without hemorrhagic presentation, respectively; the rate was 9.9%, 6.0%, and 1.0% in patients with ≥ 2, only 1, and 0 prior hemorrhages, respectively; and the rate was 9.2% in patients with both hemorrhagic presentation and focal neurological deficit on admission.

CONCLUSIONS

The study reported an annual hemorrhage rate of 7.0% exclusively for brainstem CMs, which significantly increased if patients presented with both hemorrhagic presentation and focal neurological deficit (9.2%), or any other risk factor. Patients with a risk factor for hemorrhage needed close follow-up regardless of the number of prior hemorrhages. It should be noted that the referral bias in this study could have overestimated the annual hemorrhage rate. This study improved the understanding of the natural history of brainstem CMs, and the results are important for helping patients and physicians choose a suitable treatment option based on the risk factors and stratified annual rates.Clinical trial registration no.: ChiCTR-POC-17011575 (http://www.chictr.org.cn/).

Microsurgery vs. Gamma Knife Radiosurgery for the Treatment of Brainstem Cavernous Malformations: A Systematic Review and Meta-Analysis

Background: Brainstem cavernous malformations (BSCMs) are a subset of cerebral cavernous malformations with precarious locations and potentially devastating clinical courses. The effects and outcomes of treating BSCMs by microsurgery or gamma knife radiosurgery (GKRS) vary across studies.

Methods: We searched the Medline, Web of Science, The Cochrane Library, PubMed, and China Biology Medicine disc databases for original articles published in peer-reviewed journals of cohort studies reporting on 20 or more patients of any age with BSCMs with at least 80% completeness of follow-up.

Results: We included 43 cohorts involving 2,492 patients. Both microsurgery (RR = 0.04, 95% CI 0.01–0.16, P < 0.01) and GKRS (RR = 0.11, 95% CI 0.08–0.16, P < 0.01) demonstrated great efficacy in reducing the rehemorrhage rate after treatment for BSCMs. The incidence rates of composite outcomes were 19.8 (95% CI 16.8–22.8) and 15.7 (95% CI 11.7–19.6) after neurosurgery and radiosurgery, respectively. In addition, we found statistically significant differences in the median numbers of patients between neurosurgical and radiosurgical cohorts in terms of symptomatic intracranial hemorrhage (ICH; neurosurgical cohorts: median 0, range 0–33; radiosurgical cohorts: median 4, range 1–14; P < 0.05) and persistent focal neurological deficit (FND; neurosurgical cohorts: median 5, range 0–140; radiosurgical cohorts: median 1, range 0–3; P < 0.05).

Conclusions: The reported effects of treating BSCMs by microsurgery or GKRS are favorable for reducing recurrent hemorrhage from BSCMs. Patients in the neurosurgery cohort had a lower incidence of symptomatic ICH, while patients in the radiosurgical cohort had a lower incidence of persistent FND.

Risk Factors for Poor Postoperative Outcome and Epileptic Symptoms in Patients Diagnosed with Cerebral Cavernous Malformations

BACKGROUND AND STUDY OBJECTIVE

 Roughly 12 to 47% of individuals with cerebral cavernous malformations (CCM) are asymptomatic, while other people may present with symptoms such as epileptic seizures, neurologic deficits, and intracerebral hemorrhages (IH). The aim of this study was to report our experience of postoperative outcomes of patients diagnosed with CCMs.

PATIENTS AND METHODS

 We present a series of consecutive patients who underwent surgical treatment for a diagnosed CCM between January 2003 and March 2014. Data were retrospectively analyzed with respect to preoperative visits, operating reports, patient admission charts, and postoperative follow-up visits. The Engel scale was used to evaluate the outcome of patients with epileptic seizures.

RESULTS

 A total of 91 patients were included with a mean age of 38.8 ± 15 years (range: 2-72 years). Prior to surgery, 57 of these patients had epileptic seizures, while 25 patients recorded at least one episode of IH with a latency time of 6.7 ± 8.5 years (range: 3-240 months) in between hemorrhages. A CCM located within the brainstem was significantly associated with IH prior to surgery (p = 0.000). If the CCM was adjacent to an eloquent brain area, the postoperative outcome in terms of seizure control was significantly worse (p = 0.033). In addition, a trend for worsened outcomes according to the Engel scale was observed in patients with more than one seizure prior to surgery (p = 0.055).

CONCLUSION

 Proximity of CCMs to eloquent brain areas is a risk factor for poor postoperative outcome with respect to a lower rate of medication reduction as well as a lower rate of epileptic seizure omission. This underlines the importance of patient-specific therapeutic approaches.

Morbidity After Symptomatic Hemorrhage of Cerebral Cavernous Malformation: A Nomogram Approach to Risk Assessment

BACKGROUND AND PURPOSE

Symptomatic hemorrhage contributes to an increased risk of repeated bleeding and morbidity in cerebral cavernous malformation (CCM). A better understanding of morbidity after CCM hemorrhage would be helpful to identify patients of higher risk for unfavorable outcome and tailor individualized management.

METHODS

We identified 282 consecutive patients who referred to our institute from 2014 to 2018 for CCM with symptomatic hemorrhage and had an untreated follow-up period over 6 months after the first hemorrhage. The morbidity after hemorrhage was described in CCM of different features. Nomogram to predict morbidity was formulated based on the multivariable model of risk factors. The predictive accuracy and discriminative ability of nomogram were determined with concordance index (C-index) and calibration curve, and further validated in an independent CCM cohort of a prospective multicenter study from 2019 to 2020.

RESULTS

The overall morbidity of CCM was 26.2% after a mean follow-up of 1.9 years (range 0.5-3.5 years) since the first hemorrhage. The morbidity during untreated follow-up was associated with hemorrhage ictus (adjusted odds ratio per ictus increase, 4.17 [95% CI, 1.86-9.33]), modified Rankin Scale score at initial hemorrhage (adjusted odds ratio per point increase, 2.57 [95% CI, 1.82-3.63]), brainstem location (adjusted odds ratio, 2.93 [95% CI, 1.28-6.68]), and associated developmental venous anomaly (adjusted odds ratio, 2.21 [95% CI, 1.01-4.83]). Subgroup analysis revealed similar findings in brainstem and non-brainstem CCM. Nomogram was contracted based on these features. The calibration curve showed good agreement between nomogram prediction and actual observation. The C-index of nomogram predicting morbidity was 0.83 (95% CI, 0.77-0.88). In validation cohort, the nomogram maintained the discriminative ability (C-index, 0.87 [95% CI, 0.78-0.96]).

CONCLUSIONS

Multiple symptomatic hemorrhages, initial neurological function after hemorrhage, brainstem location, and associated developmental venous anomaly were associated with morbidity of CCM hemorrhage. The nomogram represented a practical approach to provide individualized risk assessment for CCM patients. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT04076449.

[«Cavernous angiomas» of the brainstem. Clinical manifestations, diagnosis and treatment results]

Introduction

In the current literature, brainstem hematomas and various types of vascular micromalformations are combined into the one group of diseases under the general name «cavernous angioma» (CA). This approach does not make it possible to accurately determine the indications for surgery and predict postoperative outcomes.

Objective

To analyze our own experience in the diagnosis and treatment of patients with the brainstem CA.

Material and methods

There were 515 patients with CA of the brainstem (surgery - 322, conservative treatment - 193 patients) with a follow-up period of more than 5 years. Follow-up survey implied neurological examination, analysis of Karnofsky score, MRI and CT data.

Results

We identified two main groups of patients after comparison of MRI data, intraoperative findings and biopsy data: group 1 - hematomas (191 patients, 59%), group 2 - CA (131 patients, 41%). Each group was characterized by own clinical and radiological features. Postoperative outcomes depended on the disease. Debridement of hematoma ensured early postoperative improvement in 63% of patients, no changes in 21% of cases and impairment in 16% of patients. Less favorable results were observed in patients with CA and no signs of hemorrhage. Clinical impairment occurred in 73% of cases, improvement - only in 5% of patients. The most significant regression of neurological symptoms in long-term postoperative period was observed in patients with hematomas (92% of patients). These ones noted much better clinical state compared with preoperative condition.

Conclusions

The type of brain lesion is an important predictor to determine treatment approach. Postoperative outcomes differ significantly in patients with the brainstem hematoma and CA.

Natural history of incidentally diagnosed brainstem cavernous malformations in a prospective observational cohort

There was a lack of natural history of incidental brainstem cavernous malformations (CMs), hemorrhage of which would lead to severe neuropathies. The study aimed to evaluate the prospective hemorrhage rate and neurological outcome of the disease. This prospective cohort included patients with incidental brainstem CMs referred to our institute from 2009 to 2015. The diagnosis was confirmed based on the patients' complain, physical examination, and radiographic evidence. Clinical data were collected, scheduled follow-up was performed, and the independent risk factors were identified by multivariate analysis. This cohort included 48 patients (22 female, 45.8%). The median follow-up duration was 60.7 months, and 13 prospective hemorrhages occurred within 244.0 patient-years yielding an annual hemorrhage rate of 5.3%. The hemorrhage-free survival at 1 and 5 years was 91.6% and 80.6%. Age ≥ 55 years (hazard ratio (HR) = 8.59, p = 0.003), lesion size (per 1-mm increase) (HR = 3.55, p = 0.041), developmental venous anomaly (HR = 10.28, p = 0.017), and perilesional edema (HR = 4.90, p = 0.043) were independent risk factors for hemorrhage. Seven patients (14.6%) received surgical resection, and the other 41 patients remained under observation. Neurological function was improved in 22 patients (45.8%), unchanged in 19 (39.6%), and worsened in 7 (14.6%). Prospective hemorrhage (odds ratio = 14.95, p = 0.037) was the only independent risk factor for worsened outcomes. The natural history of incidental brainstem CMs seemed to be acceptable with improved/unchanged outcomes in most patients (85.4%). These results improved our understanding of the disease, and the future study of a large cohort was required to verify our findings.

Emergency surgery for brainstem cavernoma haemorrhage with severe neurological presentation. Is it indicated and worthwhile?

Background: Brainstem Cavernoma (BSCM) haemorrhage is a complex condition, especially when patients present rapid neurological deterioration. Traditionally, these patients were initially treated by non-interventional means. Surgery was generally reserved for cases who presented a 'benign' evolution in a subacute/delayed fashion. Timing of surgery remains controversial. Since rebleeding is frequent and carries a high mortality, many of these patients do not tolerate this approach. Urgent/emergent surgery may be indicated and lifesaving.Methods: A single center experience is reported in which an aggressive approach was used with urgent/emergency surgery carried out on patients with BSCM haemorrhage and rapid neurological deterioration, ventilatory impairment and/or coma. A review of 5 consecutive cases where urgent/emergent surgery was performed is presented. The pre-operative status, pre- and post-operative examinations, surgical approach and neurological residual deficits/outcomes are reported.Results: Four females and one male with ages ranging from 36 to 66 years with rapid neurological deterioration, ventilatory impairment and/or coma were operated between 2011 and 2018. Favourable outcomes were observed with a modified Rankin Scale varying from 1 to 4. Cranial nerve deficits as well as motor and sensitive deficits were observed but all the patients recovered cognitive integrity.Conclusions: Our small series reveals an acceptable outcome with ultra-early surgery. This approach appears to be a valid option when there is rapid neurological deterioration, respiratory impairment and/or early onset coma. However, further studies are required to elucidate the optimal strategy.

Brainstem cavernous malformations - no longer a forbidden territory? A systemic review of recent literature

BACKGROUND

Due to its eloquent location and potentially devastating neurological consequences, the management of brainstem cavernous malformations (CCMs) attracts considerable debate. There is currently a paucity of Level 1 evidence for their management. The aim of this literature review is to explore the current evidence on the risk-benefit profile of different management options.

METHODS

A systemic literature search, following the PRISMA algorithm was performed on publications between 2010 and 2018 using the Pubmed database, with the relevant keywords. Only English articles were included. Articles focusing on spinal CCMs and studies with less than 30 participants were excluded.

RESULTS

A total of 222 search results were reviewed and after removal of duplicates and screening of abstracts, 28 clinical papers comprising 30 or more brainstem CCM cases were included in the study. The heterogeneity of the publications precluded a formal meta-analysis of results. The general consensus is that for CCMs presenting with severe symptoms and/or multiple haemorrhages that reach an accessible pial surface, surgery is considered to be the gold-standard treatment, with some authors suggesting the optimal timing to be within two to six weeks of ictus. For those patients with multiple, deep-seated CCM related haemorrhages that do not reach the pial surface, stereotactic radiosurgery (SRS) can be considered. Conservative treatment is generally considered in incidental cases. Management of brainstem cavernomas of other categories still remains controversial.

CONCLUSIONS

Due to their highly eloquent location, brainstem CCMs are challenging lesions to manage. Management must be balanced by the risk-benefit profile and tailored to the individual patients and their treating clinicians. This review provides a comprehensive reference considering all treatment options and provides a basis for evidence-based patient counselling.

Surgical managements and patient outcomes after severe hemorrhagic events from brainstem cavernous malformations

To evaluate the surgical outcomes and predictors and the impact of surgical timing of patients who suffered a severe hemorrhagic event from brainstem cavernous malformations (CMs). The clinical data of all patients who underwent surgical treatment after a severe bleeding ictus from brainstem CMs between 2011 and 2017 were retrospectively reviewed. The study population consisted of 61 surgical patients (40, 65.6% female). Surgical times of < 3 weeks, ≥ 3-8 weeks, and > 8 weeks since the last bleeding ictus were observed in 23 (37.7%), 24 (39.3%), and 14 (23.0%) patients, respectively. The mean modified Rankin scale (mRS) score evaluated on admission was 4.2. With a mean follow-up of 39.8 months, 39 patients (63.9%) had a favorable outcome (mRS ≤ 2), and the mean mRS score was 2.3. The logistic regression analysis identified age, having disrupted consciousness and/or respiration, and time to surgery from last hemorrhage as significant predictors of long-term outcome. In particular, patients with surgery performed during the acute period (< 3 weeks, P = 0.06) or chronic period (> 8 weeks, P = 0.01) tended to have poor outcomes when compared with those with surgery during the subacute period (≥ 3-8 weeks). Favorable neurological outcomes can be achieved in patients who were surgically treated after a severe hemorrhagic ictus from brainstem CMs, and operation during subacute hemorrhage (≥ 3-8 weeks) could benefit these patients.

Surgical treatment of pontine cavernous malformations via subtemporal transtentorial and intradural anterior transpetrosal approaches

The aim of this study was to report our surgical experience on resection of the pontine cavernous malformations (CMs) via subtemporal transtentorial approach (STTA) and intradural anterior transpetrosal approach (ATPA). Clinical data were retrospectively reviewed in 61 patients with pontine CMs that were surgically treated by the STTA and the intradural ATPA. The surgical procedures, complications, and outcomes were analyzed. The study consists of 61 patients with a total of 61 pontine CMs. Other than 4 lesions located medially in the pons, all CMs were in the lateral pons with a left or right lateral epicenter (the left/right ratio was 22/35). Totally, 11 patients (18.0%) with lesions located in the upper pons were treated by the STTA, and 50 patients (82.0%) with lesions involving the lower pons were treated by the intradural ATPA. Postoperatively, the complete resection was achieved in 58 patients (95.1%) and incomplete resection in 3 patients (4.9%). Twenty-seven patients (44.3%) suffered from a new or worsened neurological deficit in the immediate postoperative period, and 8 patients (13.1%) encountered a non-neural complication, including rebleeding, cerebrospinal fluid leak, intracranial infection, and pulmonary infection, and 3 patients had contusion of temporal lobe. With a mean follow-up of 54.2 months, the patients' neurological condition had improved in 43 cases (71.6%), not changed in 10 cases (16.7%), and worsened in 7 cases (11.7%), respectively. The Karnofsky Performance Scale (KPS) score evaluated at the last time for per patient was significantly better than their baseline status (t = 6.677, p < 0.001). However, 21 patients (35.0%) suffered from a new or worsened persistent postoperative deficit. The lateral and anterolateral pons can be exposed well by the subtemporal transtentorial and intradural anterior transpetrosal approaches. Lesions of CMs located in the lateral pons, including ventrolateral and dorsolateral pons, could be totally removed by these two lateral approaches with an acceptable surgical morbidity.

Management and Surgical Approaches of Brainstem Cavernous Malformations: Our Experience and Literature Review

Introduction:

Brainstem cavernous malformations (BSCMs) are clusters of dilated sinusoidal channels. Clinical presentation is characterized by focal neurological deficits and/or hemorrhage. The goal of this study is to analyze surgical indications and approaches in a series of patients with BSCM and review pertinent literature and suggest prognostic factors related to the anatomical, clinical, and surgical data collected.

Methods:

We retrospectively reviewed the clinical data of 55 patients with BSCM, treated at three centers, from January 2006 to March 2016. We collected anagraphic data, pre and postoperative neurological status, pre and postradiological images, surgical procedures, and follow-up results. We summarized the anatomical, clinical, and surgical aspects of the lesions and identified two large groups based on the chosen approach: lateral and medial. Clinical and radiological results were then compared.

Results:

The series comprised 55 patients. Hemorrhagic onset was observed in all patients. Suboccipital, retrosigmoid, anterior, subtentorial, subtemporal, transvermian, telovelar, far lateral and trans, and infratentorial approaches were performed. Neurological status improved postoperatively in 34 cases at last follow-up. Five patients showed clinical neurological worsening. Total resection was achieved in 46 cases and, during a mean follow-up of 63.4 months, no recurrence or re-bleeding occurred in those patients. The mean follow-up was 63.9 months. The mean modified Rankin Scale at final follow-up was used to analyze the results and draw our conclusions.

Conclusions:

A reasonable surgical approach, selection, and gentle handling of the surrounding structures are required to prevent impairment of neurologic function and avoid partial resection.

Surgical outcome of motor deficits and neurological status in brainstem cavernous malformations based on preoperative diffusion tensor imaging: a prospective randomized clinical trial

OBJECTIVE: Surgical management of brainstem lesions is challenging due to the highly compact, eloquent anatomy of the brainstem. This study aimed to evaluate the safety and efficacy of preoperative diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) in brainstem cavernous malformations (CMs). METHODS: A prospective randomized controlled clinical trial was performed by using stratified blocked randomization. The primary eligibility criterion of the study was being a surgical candidate for brainstem CMs (with informed consent). The study enrolled 23 patients who underwent preoperative DTI/DTT and 24 patients who did not (the control group). The pre- and postoperative muscle strength of both limbs and modified Rankin Scale (mRS) scores were evaluated. Muscle strength of any limb at 12 months after surgery at the clinic visit was the primary outcome; worsened muscle strength was considered to be a poor outcome. Outcome assessors were blinded to patient management. This study reports the preliminary results of the interim analysis. RESULTS: The cohort included 47 patients (22 women) with a mean age of 35.7 years. The clinical baselines between these 2 groups were not significantly different. In the DTI/DTT group, the corticospinal tract was affected in 17 patients (73.9%): it was displaced, deformed/partially interrupted, or completely interrupted in 6, 7, and 4 patients, respectively. The surgical approach and brainstem entry point were adjusted in 3 patients (13.0%) based on DTI/DTT data. The surgical morbidity of the DTI/DTT group (7/23, 30.4%) was significantly lower than that of the control group (19/24, 79.2%, p = 0.001). At 12 months, the mean mRS score (1.1, p = 0.034) and percentage of patients with worsened motor deficits (4.3%, p = 0.006) were significantly lower in the DTI/DTT group than in the control group (1.7% and 37.5%). Multivariate logistic regression identified the absence of preoperative DTI/DTT (OR 0.06, 95% CI 0.01-0.73, p = 0.028) and use of the 2-point method (OR 4.15, 95% CI 1.38-12.49, p = 0.011) as independent adverse factors for a worsened motor deficit. The multivariate model found a significant correlation between poor mRS score and both an increased preoperative mRS score (t = 3.559, p = 0.001) and absence of preoperative DTI/DTT (t = -2.747, p = 0.009). CONCLUSIONS: DTI/DTT noninvasively allowed for visualization of the anatomical relationship between vital tracts and pathologies as well as facilitated the brainstem surgical approach and entry-point decision making. The technique was valuable for complex neurosurgical planning to reduce morbidity. Nonetheless, DTI/DTT data should be interpreted cautiously.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class I. Clinical trial registration no.: NCT01758211 (ClinicalTrials.gov).

Timing of Surgery and Surgical Strategies in Symptomatic Brainstem Cavernomas: Review of the Literature

Brainstem cavernomas (BSCs) are angiographically occult, benign low flow vascular malformations that pose a significant surgical challenge due to their eloquent location. The present study includes an extensive review of the literature and three illustrative cases of BSC with emphasis on the timing of surgery: surgical approaches, usage of intraoperative monitoring, and complication avoidance. A systematic search was performed using the PubMed database was from January 1, 1999, to June 2018. The relevant articles were reviewed with particular attention to hemorrhage rates, timing of surgery, indications for surgery, surgical approaches, and outcome. Along with this, a retrospective analysis of three cases of symptomatic BSC, who were operated for the same, during the year 2018 in our institute was conducted. All the three patients presented with at least 1 episode of hemorrhage before surgery. Of these, one patient was operated immediately due to altered sensorium whereas the other two were operated after at least 4 weeks of the hemorrhagic episode. The patients who were operated in the subacute phase of bleed were seen to have liquefaction of hematoma, thus providing a good surgical demarcation and thereby reduced surgery-related trauma to the surrounding eloquent structures. Two patients improved neurologically during the immediate postoperative period, whereas one had transient worsening of neurological deficits during the immediate postoperative period in the form of additional cranial nerve palsies which completely improved on follow-up after 2 months. Radical resection is recommended in all patients with symptomatic BSCs. Surgery should be considered after the first or the second episode of hemorrhage as multiple rebleeds can cause exacerbation of deficits and sometimes mortality as well. Considering surgical timing, anywhere between 4 and 6 weeks or the subacute phase of the hemorrhage is considered appropriate. The aims of surgical intervention must be to improve preoperative function, minimize surgical morbidity and to reduce hemorrhagic rates. In spite of the significant surgical morbidity associated with BSCs, appropriate patient selection, meticulous surgical planning with adjuncts such as intraoperative monitoring and neuronavigation will go a long way in avoidance of major postoperative complications.

Brain Stem Cavernous Malformations: Operative Nuances of a Less-Invasive Resection Technique

BACKGROUND

Different operative techniques are reported for the resection of brainstem cavernous malformations (BSCMs). The senior author has previously reported on a less-invasive technique of entering the brain stem with piecemeal removal of BSCMs, especially the deep-seated ones.

OBJECTIVE

To present a larger series of these lesions, emphasizing the approach to the brain stem via case selection. We discuss the nuances of the less-invasive operative technique through case illustrations and intraoperative videos.

METHODS

A retrospective review of 46 consecutive cases of BSCMs, with their clinical and radiographic data, was performed. Nine cases were selected to illustrate 7 different operative approaches, and discuss surgical nuances of the less-invasive technique unique to each.

RESULTS

Postoperative morbidity, defined as an increase in modified Rankin Scale, was observed in 5 patients (10.9%). A residual BSCM was present in 2 patients (4.3%); both underwent reoperation to remove the remainder. At follow-up of 31.1 ± 27.8 mo, 3 patients experienced recurrence (6.5%). Overall, 65% of our patients improved, 20% stayed the same, and 11% worsened postsurgery. Two patients died, yielding a mortality of 4.3%.

CONCLUSION

Using the less-invasive resection technique for piecemeal BSCM removal, in appropriately selected patients, has yielded comparable to improved patient outcomes over existing large series. In our experience, lateral, anterolateral, and posterolateral approaches are favorable over direct midline (dorsal or ventral) approaches. A thorough understanding of brain-stem safe-entry zones, in conjunction with appropriate approach selection, is key to a good outcome in challenging cases.

Intensive, functional training leads to optimal outcomes in a young woman post brain stem hemorrhage due to cerebral cavernous malformation

PURPOSE

Cerebral cavernous malformations (CCMs) can cause intracranial hemorrhages and account for 5-15% of all cerebral vascular malformations. The purpose of this retrospective case report is to describe the unusual motor recovery of a young woman following a large hemorrhage of a previously unknown brainstem CCM, otherwise not reported in the literature. Case Description: The patient was a 29-year-old female who presented with severe hemiparesis on the left 6 weeks after a first-ever hemorrhage. She had demonstrated minimal improvement in her motor recovery to date, was dependent on a walker for ambulation, and had no distal left upper extremity function. An intensive evidence-based plan of care over 6 weeks included progressive task-specific strengthening, treadmill training, and dynamic balance training. Outcomes: The patient achieved complete motor recovery, indicated by improvement from 23/66 to 64/66 in the Fugl-Meyer Upper Extremity Subscale score and from 12/30 to 30/30 in the Functional Gait Assessment. She returned to independent ambulation with functional gait speeds and kinematics. Discussion: This case report demonstrates an unusual clinical course of unexpected full recovery in a young woman after a large brainstem CCM after an intensive 6-week course of physical therapy. Other patients with a similar presentation after CCM may benefit from an intensive plan of care. Clinicians should be aware of the possibility of unusual recovery in this population as not to limit expectations for recovery.

Brainstem and cerebellar cavernous malformations

Cavernous malformations are vascular lesions that occur throughout the central nervous system, most commonly in the supratentorial location, with brainstem and cerebellar cavernous malformations occurring more rarely. Cavernous malformations are associated with developmental venous anomalies that occur sporadically or in familial form. Patients with a cavernous malformation can present with headaches, seizures, sensorimotor disturbances, or focal neurologic deficits based on the anatomic location of the lesion. Patients with infratentorial lesions present more commonly with a focal neurologic deficit. Cavernous malformations are increasingly discovered incidentally due to the increasing use of magnetic resonance imaging. Understanding the natural history of these lesions is essential to their management. Observation and surgical resection are both reasonable options in the treatment of patients with these lesions. The clinical presentation of the patient, the location of the lesion, and the surgical risk assessment all play critical roles in management decision-making.

Rebleeding and Outcome in Patients with Symptomatic Brain Stem Cavernomas

Purpose: We sought to evaluate the long-term functional outcomes and identify the potential risk factors for rebleeding in patients with brain stem cavernous malformations (BCMs) who presented with hemorrhages and were surgically or conservatively treated and prospectively monitored. Methods: From January 1990 to July 2015, we included patients with first hemorrhagic episodes secondary to single BCMs. Modified Rankin score (mRS) was used for neurological status assessment. Univariate and multivariate regression statistics were used to identify the risk factors for rebleeding. Results: A total of 99 patients with BCMs hemorrhages were included (59 [59.6%] women, mean age 37± 13 years). As initial treatments, 37 patients (37.4%) underwent surgery and 62 (62.6%) received conservative treatment. The median follow-up was 3.33 years (interquartile range 1.16-7 years; 408.3 patient/years). The rebleeding rate by patient/year was 10% in conservatively treated patients. Deterioration was significantly more frequent in patients with rebleeding (p = 0.0001). At the end of the follow-up, the mRS were favorable in 49 patients (65.3%) without rebleeding, whereas only 8 (33.3%) with rebleeding evolved to favorable outcomes (p = 0.006). Lesion size >18 mm (hazards ratio, HR 3.34, 95% CI 1.54-7.26; p = 0.0001) and ventral location or crossing the brain stem's midpoint (HR 2.5, 95% CI 1.14-5.46; p = 0.022) were associated with a major risk of rebleeding in the univariate analysis, but only a lesion >18 mm remained statistically significant (HR 2.7, 95% CI 1.2-6.21; p = 0.016) in the multivariate analysis. Conclusion: A lesion size >18 mm was the principal factor associated with hemorrhage recurrence. The overall functional outcome was good. However, significant morbidity was attributable to rebleeding.

Clinical course of untreated thalamic cavernous malformations: hemorrhage risk and neurological outcomes

OBJECTIVE The natural history of cerebral cavernous malformations (CMs) has been widely studied, but the clinical course of untreated thalamic CMs is largely unknown. Hemorrhage of these lesions can be devastating. The authors undertook this study to obtain a prospective hemorrhage rate and provide a better understanding of the prognosis of untreated thalamic CMs. METHODS This longitudinal cohort study included patients with thalamic CMs who were diagnosed between 2000 and 2015. Clinical data were recorded, radiological studies were extensively reviewed, and follow-up evaluations were performed. RESULTS A total of 121 patients were included in the study (56.2% female), with a mean follow-up duration of 3.6 years. The overall annual hemorrhage rate (subsequent to the initial presentation) was calculated to be 9.7% based on the occurrence of 42 hemorrhages over 433.1 patient-years. This rate was highest in patients (n = 87) who initially presented with hemorrhage and focal neurological deficits (FNDs) (14.1%) (χ² = 15.358, p < 0.001), followed by patients (n = 19) with hemorrhage but without FND (4.5%) and patients (n = 15) without hemorrhage regardless of symptoms (1.2%). The initial patient presentations of hemorrhage with FND (hazard ratio [HR] 2.767, 95% CI 1.336-5.731, p = 0.006) and associated developmental venous anomaly (DVA) (HR 2.510, 95% CI 1.275-4.942, p = 0.008) were identified as independent hemorrhage risk factors. The annual hemorrhage rate was significantly higher in patients with hemorrhagic pres entation at diagnosis (11.7%, p = 0.004) or DVA (15.7%, p = 0.002). Compared with the modified Rankin Scale (mRS) score at diagnosis (mean 2.2), the final mRS score (mean 2.0) was improved in 37 patients (30.6%), stable in 59 patients (48.8%), and worse in 25 patients (20.7%). Lesion size (odds ratio [OR] per 0.1 cm increase 3.410, 95% CI 1.272-9.146, p = 0.015) and mRS score at diagnosis (OR per 1 point increase 3.548, 95% CI 1.815-6.937, p < 0.001) were independent adverse risk factors for poor neurological outcome (mRS score ≥ 2). Patients experiencing hemorrhage after the initial ictus (OR per 1 ictus increase 6.923, 95% CI 3.023-15.855, p < 0.001) had a greater chance of worsened neurological status. CONCLUSIONS This study verified the adverse predictors for hemorrhage and functional outcomes of thalamic CMs and demonstrated an overall annual symptomatic hemorrhage rate of 9.7% after the initial presentation. These findings and the mode of initial presentation are useful for clinicians and patients when selecting an appropriate treatment, although the tertiary referral bias of the series should be taken into account.

Surgery Approaches to Brainstem Cavernous Malformations

BACKGROUND AND PURPOSE

To summarize our experience in surgery approach to brainstem cavernous malformation (BSCM).

METHODS

A review of 23 consecutive patients with BSCM receiving surgical resection in our center between July of 2003 and June of 2014 was performed.

RESULTS

Suboccipital approach, retrosigmoid approach, infratentorial-supracerebellar approach, Poppen approach, pterional approach, Kawase approach, and interhemispheric transcallosal-third ventrical approach were applied, of which the last 2 approaches being firstly reported in BSCM surgery. Gross total resection was achieved in 22 patients, whereas subtotal resection in 1. Neurologic function was improved in 15 patients, unchanged in 7 patients, and deteriorated in 1 patient. During a mean follow-up of 3.5 years, no recurrence occurred.

CONCLUSIONS

Proper surgery approach is important to assure total resection, protect normal vital structures, and avoid recurrence.

Natural history of cavernous malformation: Systematic review and meta-analysis of 25 studies

OBJECTIVE

We pooled the results of studies on natural history of cavernous malformations (CM) to calculate point estimates and investigate main sources of heterogeneity.

METHODS

We searched MEDLINE, EMBASE, and ISI Web of Science for relevant studies published before May 2015. We used fixed or random effects models and meta-regression to pool the data.

RESULTS

Twenty-five studies were entered into the meta-analysis (90-1,295 patients depending on the analysis). Bleeding was defined as symptomatic hemorrhage plus radiologic evidence of hemorrhage. Sources of heterogeneity were identified as mixture of hemorrhage and rehemorrhage, mixture of rehemorrhage before and after 2 years of first bleeding, brainstem vs other locations, and calculation method. The rehemorrhage rate was higher than the hemorrhage rate (incidence rate ratio 16.5, p < 0.001, 95% confidence interval [CI] 9.7-28.0). Rehemorrhage within 2 years of the first hemorrhage was higher than after that (incidence rate ratio 1.8, p = 0.042, 95% CI 1.5-2.0). In two metaregression models, rough estimate of the annual incidence rate of hemorrhage was 0.3% (95% CI 0.1%-0.5%) and 2.8% (2.5%-3.3%) per person year in nonbrainstem and brainstem lesions and rough estimate of annual rehemorrhage rate per person year was 6.3% (3%-13.2%) and 32.3% (19.8%-52.7%) in nonbrainstem and brainstem lesions. Median time to rehemorrhage was 10.5 months. Posthemorrhage full recovery was 38.8%/person-year (28.7%-48.8%). Posthemorrhage full recovery or minimal disability was 79.5%/person-year (74.3%-84.8%). Mortality after bleeding was 2.2%.

CONCLUSIONS

The incidence of symptomatic hemorrhage or rehemorrhage is higher in brainstem lesions. First symptomatic hemorrhage increases the chance of symptomatic rehemorrhage, which decreases after 2 years.

The Associated Venous Anomalies Variant and Adjacent Brain Function on Iron Sensitive Image Indicate Surgical Risk of Cavernous Malformation

The cavernous malformations (CMs) associated with venous anomalies (VAs) are now being described with increasing frequency. Assessment of the associated VAs is overlooked in surgical management of the CM. The clinical profiles of CMs with VAs were reviewed to investigate the value of T₂*gradient echo (GRE)/susceptibility weighted imaging (SWI) in surgical risk evaluation. Twenty-six patients with symptomatic CMs associated with VAs between 2008 and 2013 were identified. Demographic, clinical, and radiological data were reviewed and functional outcomes were assessed using the modified Rankin Scale (mRS). The T₂*GRE/SWI could allow more accurate evaluation of the boundary and drainage vicinity of VAs than contrast-enhanced images (6 vs. 2 patients with VAs on the eloquent region). Patients with VAs adjacent to eloquent brain showed poorer outcomes than those who had VAs in non-eloquent areas (P = 0.005), while the CMs adjacent to eloquent brain did not correlated with poor outcomes (P = 0.15). Type I and III variants of VAs were also significantly associated with poor outcomes, compared with type II variant (P = 0.002). Careful evaluation of VAs variant type and the association between VAs and eloquent brain is helpful for the management of CMs associated with VAs. We recommend T₂*GRE/SWI in patients with CMs to assess the associated VAs. The evaluation of VA drainage vicinity on T₂*GRE/SWI would be more useful for designing treatment strategies and risk stratification.

Prospective Hemorrhage Rates of Cerebral Cavernous Malformations in Children and Adolescents Based on MRI Appearance

BACKGROUND AND PURPOSE

Current classifications of cerebral cavernous malformations focus solely on morphologic aspects. Our aim was to provide a morphologic classification that reflects hemorrhage rates.

MATERIALS AND METHODS

We retrospectively categorized 355 cavernous malformations of 70 children and adolescents according to their morphologic appearance on MR imaging and calculated prospective hemorrhage rates on the basis of survival functions for 255 lesions in 25 patients with a radiologic observation period of >180 days.

RESULTS

Overall, there were 199 MR imaging examinations with 1558 distinct cavernous malformation observations during a cumulative observation period of 1094.2 lesion-years. The mean hemorrhage rate of all 355 cavernous malformations was 4.5% per lesion-year. According to Kaplan-Meier survival models, Zabramski type I and II cavernous malformations had a significantly higher hemorrhage rate than type III and IV lesions. The presence of acute or subacute blood-degradation products was the strongest indicator for an increased hemorrhage risk (P = .036, Cox regression): The mean annual hemorrhage rate and mean hemorrhage-free interval for cavernous malformations with and without signs of acute or subacute blood degradation products were 23.4% and 22.6 months and 3.4% and 27.9 months, respectively. Dot-sized cavernous malformations, visible in T2* and not or barely visible in T1WI and T2WI sequences, had a mean annual hemorrhage rate of 1.3% and a mean hemorrhage-free interval of 37.8 months.

CONCLUSIONS

It is possible to predict hemorrhage rates based on the Zabramski classification. Our findings imply a tripartite classification distinguishing lesions with and without acute or subacute blood degradation products and dot-sized cavernous malformations.

A systematic review and meta-analysis of surgeries performed for treating deep-seated cerebral cavernous malformations

OBJECTIVE

The clinical benefit of surgery for treatment of deep-seated cerebral cavernous malformations (CCMs) is still a matter of debate. Although the surgical removal of CCMs is widely accepted, the benefits of reducing the rate of haemorrhage must be balanced against the risk of peri-operative morbidity. Here, we provide a systematic review and meta-analysis of the clinical benefits of surgery for treating deeply localised CCMs.

METHODS

A comprehensive search of PubMed and Embase was conducted to identify relevant studies. The rate and a 95% confidence interval (CI) were used to measure the risk of haemorrhage and adverse outcomes.

RESULTS

A total of 34 cohort studies reporting surgeries on CCMs were included in our analysis. Overall, the average post-surgical haemorrhage rate was 1.0% (95% CI: 0.7-1.4%). Nine per cent (95% CI: 6.9-11.3%) of the patients developed adverse events at follow-up following the surgical resection of deep-seated CCMs. The percentage of transient neural defects following surgical resection was 34.6% (95% CI: 29.4-39.9%). The proportions of transient focal neurological defect before and after the year 2006 were 44.9% (95% CI: 34.1-55.8%) and 30.3% (95% CI: 25.1-35.9%), respectively.

CONCLUSIONS

Our meta-analysis demonstrates post-surgical haemorrhage rate and complications related to surgeries on deep-seated CCMs. The post-surgical haemorrhage rate was low with a relatively high rate of post-surgical complications.

Management of cerebral cavernous malformations: from diagnosis to treatment

Cerebral cavernous malformations are the most common vascular malformations and can be found in many locations in the brain. If left untreated, cavernomas may lead to intracerebral hemorrhage, seizures, focal neurological deficits, or headaches. As they are angiographically occult, their diagnosis relies on various MR imaging techniques, which detect different characteristics of the lesions as well as aiding in planning the surgical treatment. The clinical presentation and the location of the lesion are the most important factors involved in determining the optimal course of treatment of cavernomas. We concisely review the literature and discuss the advantages and limitations of each of the three available methods of treatment—microsurgical resection, stereotactic radiosurgery, and conservative management—depending on the lesion characteristics.

Electrocorticography-guided surgical treatment of solitary supratentorial cavernous malformations with secondary epilepsy

OBJECTIVE

To evaluate the efficacy of electrocorticographic (ECoG) monitoring and the application of different surgical approaches in the surgical treatment of solitary supretentorial cavernous malformations with secondary epilepsy.

METHODS

This study enrolled a consecutive series of 36 patients with solitary supratentorial cavernous malformations and secondary epilepsy who underwent surgery with intraoperative ECoG monitoring in the Department of Neurosurgery between January 2004 and January 2008. The patients were composed of 15 males and 21 females, aged between 8 and 52 years (mean age 27.3±2.8 years) at the time of surgery. Epilepsy history, the type of epilepsy at the presentation, lesion location, the incidence of residual epileptiform discharges, and postoperative outcomes were evaluated.

RESULTS

Histopathological examination indicated cavernous malformations and hippocampal sclerosis in 36 and 5 cases, respectively. Neuronal degeneration, glial cell proliferation, and neurofibrillary tangles were found in all the resected cerebral tissues of extended lesionectomy of residual epileptic foci. Lesionectomy, anterior temporal lobectomy, anterior temporal lobectomy plus cortical thermocoagulation, extended lesionectomy, extended lesionectomy plus cortical thermocoagulation were performed in 4, 4, 1, 14, and 13 cases, respectively. Residual epileptiform discharges were captured in 9 out of the 14 patients who had additional cortical thermocoagulation. According to Engle class for postoperative outcomes, 27 cases were class I (75.00%), 5 were class II (13.89%), 2 were class III (5.56%), and 2 were class IV (5.56%), thus the total effective rate (class I+class II) was 88.89%. Neither of epilepsy history, the type of epilepsy, and the location of cavernous malformation was significantly related to outcomes (P>0.05). A significant relationship was found between the incidence of residual epileptiform discharges and outcomes (P=0.041).

CONCLUSIONS

Intraoperative ECoG monitoring, the application of different surgical approaches, and the resection of residual epileptic foci could produce good result in the surgical treatment of supratentorial cavernous malformation with secondary epilepsy. Postoperative residual epileptiform discharges could be a useful predictor for evaluating the outcomes.