Guidelines for the Diagnosis and Clinical Management of Cavernous Malformations of the Brain and Spinal Cord

Neurosurgery 98:3–22, 2026

These guidelines present updated, evidence-based recommendations for diagnosing and managing cavernous malformations (CMs) of the brain and spinal cord, produced by an expert multidisciplinary panel convened by the Alliance to Cure Cavernous Malformation. The document summarizes systematic literature review methods, evidence ratings, and 53 consensus recommendations across epidemiology, genetics, imaging, neurosurgery, and neurology.

Key clinical guidance addresses diagnostic MRI protocols, genetic testing for familial CM (KRIT1/CCM2/PDCD10), surgical/radiosurgical indications including pediatric and geriatric considerations, seizure and headache management, and lifestyle and medication factors potentially affecting hemorrhage risk. Recommendations highlight evidence limitations and prioritize further research.

Diagnosis: MRI with susceptibility-weighted sequences is the gold standard for diagnosing cavernous malformations (CMs); CT may be used in emergencies, but MRI is preferred for follow-up and detailed assessment.

Genetic Testing: Genetic testing for KRIT1 (CCM1), CCM2, and PDCD10 (CCM3) is recommended for individuals with multiple CMs, a family history, or suspected familial CM (FCM); founder mutations exist in certain populations.

Hemorrhage Risk: Annual risk of symptomatic intracranial hemorrhage (ICH) from CMs ranges from 0.7% to 7.5%, with higher risk for recurrent bleeds and in familial cases, especially with CCM3 mutations.

Surgical Management: Surgery is generally reserved for symptomatic, accessible CMs or those causing drug-resistant epilepsy; conservative management is preferred for asymptomatic or deep/eloquent area lesions unless recurrent bleeds occur.

Medical Management: Antiseizure medication is recommended after a first CM-related seizure; standard migraine therapy applies for nonhemorrhagic CMs, and nonaspirin NSAIDs can be used cautiously.

Pregnancy: Pregnancy does not increase the risk of CM hemorrhage compared to nonpregnant states; MRI without contrast is advised for new neurological symptoms during pregnancy.

Medication Risks: Antithrombotic agents (e.g., aspirin) do not increase and may actually lower CM hemorrhage risk, while female hormones may increase risk; thrombolytic use remains controversial and should be considered on a case-by-case basis.

Lifestyle and Emerging Therapies: Vitamin D supplementation, aerobic activity, and a diet low in processed foods are reasonable lifestyle recommendations; propranolol and statins show potential but lack definitive evidence for reducing hemorrhage risk.

A taxonomy for superficial cerebral cavernous malformations: subtypes of cortical and subcortical lesions

J Neurosurg 141:123–137, 2024

A taxonomy for superficial cerebral cavernous malformations (CMs), those based cortically in gyral gray matter or subcortically in underlying white matter, is proposed to build on the comprehensive, systematic characterization of CMs in the entire brain.

METHODS Patients with superficial cerebral CMs were retrospectively analyzed from a consecutive surgical series between November 2008 and June 2021 at the authors’ center. Superficial cerebral CMs were categorized into 4 subtypes based on their cortical location or, if subcortical, proximity to the nearest cerebral surface: convexity, medial, basal, and sylvian. Lobar location was also included for subtyping: frontal, temporal, parietal, and occipital.

RESULTS A total of 362 CMs were resected in 346 patients. CM subtypes were as follows: 132 (36.5%) convexity, 78 (21.5%) medial, 72 (19.9%) basal, and 80 (22.1%) sylvian. Frontal CMs were most common (155 [42.8%]), followed by parietal (89 [24.6%]), temporal (87 [24.0%]), and occipital (31 [8.6%]). Of all CMs, 302 (83.4%) were cortical and 60 (16.6%) were subcortical. The mean subcortical depth of deep lesions was 2.97 cm, and the mean lesion volume was 4.68 cm 3 . Overall, 228 lesions (63.0%) were resected through a transgyral approach, and 134 (37.0%) were resected through a transsulcal approach. Good outcomes (modified Rankin Scale [mRS] score ≤ 2) were observed in 314 patients (86.7%) and poor outcomes (mRS score > 2) in 25 patients (6.9%), and 23 patients (6.4%) were lost to late follow-up (mean follow-up duration 11.5 months). Relative outcomes were good (unchanged or improved mRS score) in 327 patients (90.3%) and poor (worse or died) in 35 patients (9.7%).

CONCLUSIONS Superficial cerebral CMs were resected through a gyrus or sulcus to open the subarachnoid dissection corridors, traversing the full extent of sulci to deepen the approach and minimize tissue transgression. Transgyral dissection avoids associated arteries but is inherently transgressive, whereas transsulcal dissection preserves cortical tissue and may reduce morbidity. Superficial cerebral CMs occupy the largest territory of the 7 types, and the size and surface complexity of the cerebrum make taxonomic subtyping valuable for clear anatomical description.

A taxonomy for deep cerebral cavernous malformations: subtypes of thalamic lesions

J Neurosurg 139:1681–1696, 2023

Anatomical taxonomy is a practical tool to successfully guide clinical decision-making for patients with brain arteriovenous malformations and brainstem cavernous malformations (CMs). Deep cerebral CMs are complex, difficult to access, and highly variable in size, shape, and position. The authors propose a novel taxonomic system for deep CMs in the thalamus based on clinical presentation (syndromes) and anatomical location (identified on MRI).

METHODS The taxonomic system was developed and applied to an extensive 2-surgeon experience from 2001 through 2019. Deep CMs involving the thalamus were identified. These CMs were subtyped on the basis of the predominant surface presentation identified on preoperative MRI. Six subtypes among 75 thalamic CMs were defined: anterior (7/75, 9%), medial (22/75, 29%), lateral (10/75, 13%), choroidal (9/75, 12%), pulvinar (19/75, 25%), and geniculate (8/75, 11%). Neurological outcomes were assessed using modified Rankin Scale (mRS) scores. A postoperative score ≤ 2 was defined as a favorable outcome and > 2 as a poor outcome. Clinical and surgical characteristics and neurological outcomes were compared among subtypes.

RESULTS Seventy-five patients underwent resection of thalamic CMs and had clinical and radiological data available. Their mean age was 40.9 (SD 15.2) years. Each thalamic CM subtype was associated with a recognizable constellation of neurological symptoms. The common symptoms were severe or worsening headaches (30/75, 40%), hemiparesis (27/75, 36%), hemianesthesia (21/75, 28%), blurred vision (14/75, 19%), and hydrocephalus (9/75, 12%). The thalamic CM subtype determined the selection of surgical approach. A single approach was associated with each subtype for most patients. The main exception to this paradigm was that in the surgeons’ early experience, pulvinar CMs were resected through a superior parietal lobule–transatrial approach (4/19, 21%), which later evolved to the paramedian supracerebellar-infratentorial approach (12/19, 63%). Relative outcomes implied by mRS scores were unchanged or improved in most patients (61/66, 92%) postoperatively.

CONCLUSIONS This study confirms the authors’ hypothesis that this taxonomy for thalamic CMs can meaningfully guide the selection of surgical approach and resection strategy. The proposed taxonomy can increase diagnostic acumen at the patient bedside, help identify optimal surgical approaches, enhance the clarity of clinical communications and publications, and improve patient outcomes.

Cavernous angiomas: deconstructing a neurosurgical disease

J Neurosurg 131:1–13, 2019

Cavernous angioma (CA) is also known as cavernoma, cavernous hemangioma, and cerebral cavernous malformation (CCM) (National Library of Medicine Medical Subject heading unique ID D006392). In its sporadic form, CA occurs as a solitary hemorrhagic vascular lesion or as clustered lesions associated with a developmental venous anomaly. In its autosomal dominant familial form (Online Mendelian Inheritance in Man #116860), CA is caused by a heterozygous germ-line loss-of-function mutation in one of three genes—CCM1/KRIT1, CCM2/Malcavernin, and CCM3/PDCD10—causing multifocal lesions throughout the brain and spinal cord.

In this paper, the authors review the cardinal features of CA’s disease pathology and clinical radiological features. They summarize key aspects of CA’s natural history and broad elements of evidence-based management guidelines, including surgery. The authors also discuss evidence of similar genetic defects in sporadic and familial lesions, consequences of CCM gene loss in different tissues at various stages of development, and implications regarding the pathobiology of CAs.

The concept of CA with symptomatic hemorrhage (CASH) is presented as well as its relevance to clinical care and research in the field. Pathobiological mechanisms related to CA include inflammation and immune-mediated processes, angiogenesis and vascular permeability, microbiome driven factors, and lesional anticoagulant domains. These mechanisms have motivated the development of imaging and plasma biomarkers of relevant disease behavior and promising therapeutic targets.

The spectrum of discoveries about CA and their implications endorse CA as a paradigm for deconstructing a neurosurgical disease.

 

Hemorrhage risks and functional outcomes of untreated brainstem cavernous malformations

brainstem cavernous malformations

J Neurosurg 121:32–41, 2014

Cerebral cavernous malformations have been studied widely, but the natural history of brainstem cavernous malformations (CMs) is not well defined, and hemorrhages caused by brainstem CMs are devastating. The goal of this study was to quantify the hemorrhage risks and functional outcomes of patients with brainstem CMs.

Methods. This prospective, longitudinal, cohort study included patients with brainstem CMs diagnosed between 1985 and 2012. The clinical courses of all patients were recorded. Predictors of hemorrhage and the overall untreated outcomes were evaluated.

Results. A total of 331 patients (46.5% female) were included, with a mean follow-up duration of 6.5 years. The annual hemorrhage rates in patients initially presenting with hemorrhage with (n = 215) or without (n = 34) focal neurological deficits were 15.9% and 12.4%, respectively. However, the annual hemorrhage rate was 8.7% in patients initially presenting without hemorrhage (n = 82). The risk factors for hemorrhage were female sex (hazard ratio [HR] 1.445, p = 0.041), prior hemorrhage (HR 1.277, p = 0.029), and perilesional edema (HR 1.830, p = 0.002). Overall, neurological function at the most recent assessment was improved compared with neurological function at diagnosis. Additionally, 307 patients (92.7%) improved or stabilized, 268 (81.0%) lived independently, and 95 (28.7%) completely recovered. Predictors favoring complete recovery were no prospective hemorrhage (HR 1.958, p = 0.001), younger age (HR 1.268, p = 0.001), and small lesion size (HR 1.578, p = 0.004).

Conclusions. Patients’ initial presentation predicts their prospective annual hemorrhage rate. This study suggests that several strong risk factors for hemorrhage and predictors of brainstem CM outcomes may enable clinicians to evaluate the potential hemorrhage risks of their patients and design personalized treatments.