Gamma knife surgery of brain cavernous hemangiomas

Stereotactic radiosurgery for haemorrhagic cerebral cavernous malformation: a multi-institutional, retrospective study

BACKGROUND

Cerebral cavernous malformations (CCMs) frequently manifest with haemorrhages. Stereotactic radiosurgery (SRS) has been employed for CCM not suitable for resection. Its effect on reducing haemorrhage risk is still controversial. The aim of this study was to expand on the safety and efficacy of SRS for haemorrhagic CCM.

METHODS

This retrospective multicentric study included CCM with at least one haemorrhage treated with single-session SRS. The annual haemorrhagic rate (AHR) was calculated before and after SRS. Recurrent event analysis and Cox regression were used to evaluate factors associated with haemorrhage. Adverse radiation effects (AREs) and occurrence of new neurological deficits were recorded.

RESULTS

The study included 381 patients (median age: 37.5 years (Q1-Q3: 25.8-51.9) with 414 CCMs. The AHR from diagnosis to SRS excluding the first haemorrhage was 11.08 per 100 CCM-years and was reduced to 2.7 per 100 CCM-years after treatment. In recurrent event analysis, SRS, HR 0.27 (95% CI 0.17 to 0.44), p<0.0001 was associated with a decreased risk of haemorrhage, and the presence of developmental venous anomaly (DVA) with an increased risk, HR 1.60 (95% CI 1.07 to 2.40), p=0.022. The cumulative risk of first haemorrhage after SRS was 9.4% (95% CI 6% to 12.6%) at 5 years and 15.6% (95% CI% 9 to 21.8%) at 10 years. Margin doses> 13 Gy, HR 2.27 (95% CI 1.20 to 4.32), p=0.012 and the presence of DVA, HR 2.08 (95% CI 1.00 to 4.31), p=0.049 were factors associated with higher probability of post-SRS haemorrhage. Post-SRS haemorrhage was symptomatic in 22 out of 381 (5.8%) patients, presenting with transient (15/381) or permanent (7/381) neurological deficit. ARE occurred in 11.1% (46/414) CCM and was responsible for transient neurological deficit in 3.9% (15/381) of the patients and permanent deficit in 1.1% (4/381) of the patients. Margin doses >13 Gy and CCM volume >0.7 cc were associated with increased risk of ARE.

CONCLUSION

Single-session SRS for haemorrhagic CCM is associated with a decrease in haemorrhage rate. Margin doses ≤13 Gy seem advisable.

The Brainstem Cavernoma Case Series: A Formula for Surgery and Surgical Technique

Background and Objectives: Cavernous malformations (CM) are vascular malformations with low blood flow. The removal of brainstem CMs (BS) is associated with high surgical morbidity, and there is no general consensus on when to treat deep-seated BS CMs. The aim of this study is to compare the surgical outcomes of a series of deep-seated BS CMs with the surgical outcomes of a series of superficially located BS CMs operated on at the Department of Neurosurgery, College of Tuebingen, Germany. Materials and Methods: A retrospective evaluation was performed using patient charts, surgical video recordings, and outpatient examinations. Factors were identified in which surgical intervention was performed in cases of BS CMs. Preoperative radiological examinations included MRI and diffusion tensor imaging (DTI). For deep-seated BS CMs, a voxel-based 3D neuronavigation system and electrophysiological mapping of the brainstem surface were used. Results: A total of 34 consecutive patients with primary superficial (n = 20/58.8%) and deep-seated (n = 14/41.2%) brainstem cavernomas (BS CM) were enrolled in this comparative study. Complete removal was achieved in 31 patients (91.2%). Deep-seated BS CMs: The mean diameter was 14.7 mm (range: 8.3 to 27.7 mm). All but one of these lesions were completely removed. The median follow-up time was 5.8 years. Two patients (5.9%) developed new neurologic deficits after surgery. Superficial BS CMs: The median diameter was 14.9 mm (range: 7.2 to 27.3 mm). All but two of the superficial BS CMs could be completely removed. New permanent neurologic deficits were observed in two patients (5.9%) after surgery. The median follow-up time in this group was 3.6 years. Conclusions: The treatment of BS CMs remains complex. However, the results of this study demonstrate that with less invasive posterior fossa approaches, brainstem mapping, and neuronavigation combined with the use of a blunt "spinal cord" dissection technique, deep-seated BS CMs can be completely removed in selected cases, with good functional outcomes comparable to those of superficial BS CM.

Outcome of intracerebral cavernoma treated by Gamma Knife radiosurgery based on a double-blind assessment of treatment indication

BACKGROUND

The benefit and the risk profile of Gamma Knife radiosurgery (GKRS) for intracerebral cavernoma remains incompletely defined in part due to the natural history of low incidence of bleeding and spontaneous regression of this vascular malformation. In this study, we retrieved cases from a prospectively collected database to assess the outcome of intracerebral cavernoma treated with GKRS using a double blinded review process for treatment.

METHODS

From 2003 to 2018, there were 94 cases of cavernoma treated by GKRS in the doubly blinded assessments by two experienced neurological and approved for GKRS treatment. All the patients received GKRS with margin dose of 11-12 (Gray) Gy and afterwards were assessed for neurological outcome, radiologic response, and quality of life.

RESULTS

The median age of the patients was 48 (15-85) years with median follow up of 77 (26-180) months post SRS. The mean target volume was 1.93 ± 3.45 cc. In those who has pre-SRS epilepsy, 7 of 16 (43.7%) achieved seizure freedom (Engel I/II) and 9 of 16 (56.3%) achieved decreased seizures (Engel III) after SRS. Rebleeding occurred in 2 cases (2.1%) at 13 and 52 months post SRS. The radiologic assessment demonstrated 20 (21.3%) cases of decreased cavernoma volume, 69 (73.4%) were stable, and 5 (7.3%) increased size. Eighty-seven of 94 (92.5%) cases at the last follow up achieve improvement in their quality of life, but 7 cases (7.4%) showed a deterioration. In statistical analysis, the effective seizure control class (Engel I/II) was highly correlated with patient harboring a single lesion (p < 0.05) and deep seated location of the cavernoma (p < 0.01). New neurological deficits were highly correlated with decreased mental (p < 0.001) and physical (p < 0.05) components of quality of life testing, KPS (p < 0.001), deep seated location (p < 0.01), and increased nidus volume (p < 0.05). Quality of life deterioration either in physical component (p < 0.01), mental component (p < 0.01), and KPS (p < 0.05) was highly correlated with increased cavernoma volume.

CONCLUSION

Low margin dose GKRS for intracerebral cavernoma offers reasonable seizure control and improved quality of life while conferring a low risk of treatment complications including adverse radiation effect.

Stereotactic radiosurgery for the treatment of symptomatic brainstem cavernous malformations

Object

The authors performed a retrospective review of prospectively collected data to evaluate the safety and efficacy of stereotactic radiosurgery (SRS) for the treatment of patients harboring symptomatic solitary cavernous malformations (CMs) of the brainstem that bleed repeatedly and are high risk for resection.

Methods

Between 1988 and 2005, 68 patients (34 males and 34 females) with solitary, symptomatic CMs of the brainstem underwent Gamma Knife surgery. The mean patient age was 41.2 years, and all patients had suffered at least 2 symptomatic hemorrhages (range 2–12 events) before radiosurgery. Prior to SRS, 15 patients (22.1%) had undergone attempted resection. The mean volume of the malformation treated was 1.19 ml, and the mean prescribed marginal radiation dose was 16 Gy.

Results

The mean follow-up period was 5.2 years (range 0.6–12.4 years). The pre-SRS annual hemorrhage rate was 32.38%, or 125 hemorrhages, excluding the first hemorrhage, over a total of 386 patient-years. Following SRS, 11 hemorrhages were observed within the first 2 years of follow-up (8.22% annual hemorrhage rate) and 3 hemorrhages were observed in the period after the first 2 years of follow-up (1.37% annual hemorrhage rate). A significant reduction (p < 0.0001) in the risk of brainstem CM hemorrhages was observed following radiosurgical treatment, as well as in latency period of 2 years after SRS (p < 0.0447). Eight patients (11.8%) experienced new neurological deficits as a result of adverse radiation effects following SRS.

Conclusions

The results of this study support a role for the use of SRS for symptomatic CMs of the brainstem, as it is relatively safe and appears to reduce rebleeding rates in this high-surgical-risk location.

Radiosurgery for angiographically occult vascular malformations

The use of radiosurgery for angiographically occult vascular malformations (AOVMs) is a controversial treatment option for those that are surgically inaccessible or located in eloquent brain. To determine the efficacy of this treatment, the authors reviewed the literature reporting hemorrhage rates, seizure control, and radiation-induced morbidity. They found overall hemorrhage rates of 2-6.4%, overall postradiosurgery hemorrhage rates of 1.6-8%, and stratified postradiosurgery hemorrhage rates of 7.3-22.4% in the period immediately to 2 years after treatment; these latter rates declined to 0.8-5.2% > 2 years after treatment. Of 291 patients presenting with seizure across 16 studies, 89 (31%) attained a seizure-free status and 102 (35%) had a reduction in seizure frequency after radiosurgery. Overall radiation-induced morbidity ranged from 2.5 to 59%, with higher complication rates in patients with brainstem lesion locations. Researchers applying mean radiation doses of 15-16.2 Gy to the tumor margin saw both low radiation-induced complication rates (0-9.1%) and adequate hemorrhage control (0.8-5.2% > 2 years after treatment), whereas mean doses >or= 16.5 Gy were associated with higher total radiation-induced morbidity rates (> 17%). Although the use of stereotactic radiosurgery remains controversial, patients with AOVMs located in surgically inaccessible areas of the brain may benefit from such treatment.

Hemorrhage from cavernous malformations of the brain: definition and reporting standards. Angioma Alliance Scientific Advisory Board

BACKGROUND AND PURPOSE

Cavernous malformations of the brain (CMs) cause intracranial hemorrhage, but its reported frequency varies, partly attributable to study design. To improve the validity of future research, we aimed to develop a robust definition of CM hemorrhage.

METHODS

We systematically reviewed the published literature (Ovid Medline and Embase to June 1, 2007) for definitions of CM hemorrhage used in studies of the untreated clinical course of >or=20 participants with CM(s), to inform the development of a consensus statement on the clinical and imaging features of CM hemorrhage at a scientific workshop of the Angioma Alliance.

RESULTS

A systematic review of 1426 publications about CMs in humans, revealed 15 studies meeting our inclusion criteria. Although 14 (93%) studies provided a definition of CM hemorrhage, data were less complete on the confirmatory type(s) of imaging (87%), whether CM hemorrhage should be clinically symptomatic (73%), and whether hemorrhage had to extend outside the CM or not (47%). We define a CM hemorrhage as requiring acute or subacute onset symptoms (any of: headache, epileptic seizure, impaired consciousness, or new/worsened focal neurological deficit referable to the anatomic location of the CM) accompanied by radiological, pathological, surgical, or rarely only cerebrospinal fluid evidence of recent extra- or intralesional hemorrhage. The definition includes neither an increase in CM diameter without other evidence of recent hemorrhage, nor the existence of a hemosiderin halo.

CONCLUSIONS

A consistent approach to clinical and brain imaging classification of CM hemorrhage will improve the external validity of future CM research.