Feasibility and Morbidity of Magnetic Resonance Imaging-Guided Stereotactic Laser Ablation of Deep Cerebral Cavernous Malformations: A Report of 4 Cases

Cerebral cavernous malformations - An overview on genetics, clinical aspects and therapeutic strategies

Cerebral cavernous malformations (CCMs) are abnormally packed blood vessels lined with endothelial cells, that do not exhibit intervening tight junctions, lack muscular and elastic layers and are usually surrounded by hemosiderin and gliosis. CCMs may be sporadic or familial autosomal dominant (FCCMs) caused by loss of function mutations in CCM1 (KRIT1), CCM2 (MGC4607), and CCM3 (PDCD10) genes. In the FCCMs, patients have multiple CCMs, different family members are affected, and developmental venous anomalies are absent. CCMs may be asymptomatic or may manifest with focal neurological deficits with or without associated hemorrhage andseizures. Recent studies identify a digenic "triple-hit" mechanism involving the aquisition of three distinct genetic mutations that culminate in phosphatidylinositol-3-kinase (PIK3CA) gain of function, as the basis for rapidly growing and clinically symptomatic CCMs. The pathophysiology of CCMs involves signaling aberrations in the neurovascular unit, including proliferative dysangiogenesis, blood-brain barrier hyperpermeability, inflammation and immune mediated processes, anticoagulant vascular domain, and gut microbiome-driven mechanisms. Clinical trials are investigating potential therapies, magnetic resonance imaging and plasma biomarkers for hemorrhage and CCMs-related epilepsy, as well as different techniques of neuronavigation and neurosonology to guide surgery in order to minimize post-operatory morbidity and mortality. This review addresses the recent data about the natural history, genetics, neuroimaging and therapeutic approaches for CCMs.

Posterior Fossa Laser Interstitial Thermal Therapy in Children

Real-time, MRI-guided laser interstitial thermal therapy (MRgLITT) is emerging as a minimally invasive technique for epilepsy surgery and for deep-seated tumors in the pediatric population. However, MRgLITT for posterior fossa lesions poses a unique challenge that is especially evident in this age range and remains understudied. In this study, we report our experience and analyze the current literature on MRgLITT for the treatment of posterior fossa in children.

The use of stereotactic MRI-guided laser interstitial thermal therapy for the treatment of pediatric cavernous malformations: the SUNY Upstate Golisano Children's Hospital experience

PURPOSE

Cavernous malformations (CM) are central nervous system lesions characterized by interlaced vascular sinusoids coated with endothelial cells without intervening parenchyma. Magnetic resonance imaging-guided laser interstitial thermal therapy (MRIgLITT) is a minimally invasive treatment modality that can precisely treat pathologic cerebral tissue, making it an effective alternative for the management of cavernomas. We describe the outcomes of a series of pediatric patients with cavernous brain malformations treated with MRIgLITT between 2014 and 2018 at our institution.

METHODS

We retrospectively analyzed 11 cavernomas in 6 pediatric patients treated with MRIgLITT. Both the Visualase System^® and/or Neuroblate^® systems were used. A variation of the surgical technique on the application of the laser was developed. Post-ablation MRIs were obtained to assess ablated areas.

RESULTS

A total of 11 cavernomas in 6 patients were treated with MRIgLITT. Median age was 15 years (12 to 17 years); 75% were males. Presenting symptoms were headache (75%) and seizures (25%). Two patients presented with multiple CMs. All lesions in this study were supratentorial (cerebral hemispheres 81.8%, corpus callosum 9.1%, basal ganglia 9.1%). Our surgical technique was well-tolerated, with no significant adverse events observed. Hospital stay for all patients was less than 48 hours.

CONCLUSION

MRIgLITT is an effective minimally invasive technique for the treatment of pediatric CMs. It represents a useful and safe tool, when other therapeutic alternatives may represent a greater risk of surgical morbidity.

Laser Interstitial Thermal Therapy for Cerebral Cavernous Malformations: A Systematic Review of Indications, Safety, and Outcomes

BACKGROUND

Cerebral cavernous malformations (CCM) in deep eloquent areas present a surgical challenge. Laser interstitial thermal therapy (LITT) may present itself as a safe minimally invasive treatment option.

OBJECTIVE

To systematically review the indications, safety, and outcomes of LITT for CCM.

METHODS

Electronic databases were searched from inception to October 7, 2021 for articles with CCM and LITT keywords. Studies describing CCMs treated with LITT were included.

RESULTS

A total of 32 patients with CCMs in lobar (79%), basal ganglia (12%), and brainstem (9%) locations were treated with LITT. Indications for LITT included drug-resistant seizures (75%), unacceptable surgical risk (22%), recurrent hemorrhage (16%), and early intervention to discontinue antiepileptic drugs (3%). No death or CCM-associated intracranial hemorrhage occurred intraoperatively or postoperatively, and most patients experienced no adverse effects or transient effects that resolved at follow-up (84%). Of those treated for CCM-associated epilepsy, 83% experienced Engel class I seizure freedom and most were class IA (61%). Most patients experienced symptomatic improvement (93%), and a decrease in antiepileptic drugs was reported in more than half of patients (56%), with 28% able to discontinue all antiepilepsy medications after LITT.

CONCLUSIONS

LITT seems to be a safe treatment for CCMs located in deep eloquent areas and in lesions presenting with medically refractory seizures or recurrent hemorrhages. Randomized studies are needed to further elucidate its efficacy in treating CCM.

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.