Gamma knife surgery for intracranial cavernous hemangioma

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 cerebral cavernous malformations: A systematic review

OBJECTIVE

The efficacy of stereotactic radiosurgery (SRS) for the treatment of cerebral cavernous malformations (CCMs) is uncertain, so we set out to quantify clinical outcomes after SRS for CCM and compare them to microsurgical excision or conservative management.

METHODS

We searched Ovid Medline and Ovid EMBASE from inception until June 1, 2018, for peer-reviewed publications describing clinical outcomes after SRS for ≥10 people with CCM in cohorts with or without a comparison group treated with neurosurgical excision or conservative management. Two reviewers independently extracted data from the included studies to quantify cohort characteristics and the incidence of the primary outcome (death attributable to CCM or its treatment) and secondary outcomes (incident nonfatal symptomatic intracerebral hemorrhage [ICH] and incident nonhemorrhagic persistent focal neurologic deficit [FND]). We assessed whether comparative studies showed a dramatic association (meaning the conventionally calculated probability comparing 2 differently managed patient groups from the same population was <0.01 with a rate ratio greater than 10).

RESULTS

We included 30 cohort studies involving a total of 1,576 patients undergoing SRS for CCM. Four nonrandomized studies compared SRS to other treatment strategies, but did not demonstrate dramatic associations. During a median follow-up of 48 (interquartile range 35-62) months after SRS, the annual incidences (95% confidence interval) of outcomes were death 0.18% (0.10-0.31), ICH 2.40% (2.05-2.80), FND 0.71% (0.53-0.96), and the composite of death, ICH, or FND 3.63% (3.17-4.16). Outcomes did not differ by CCM location or type of SRS.

CONCLUSION

After SRS for CCM, the annual incidences of death, ICH, and FND are <5% and seem comparable to outcomes without SRS. A randomized trial of SRS for CCM is needed.

CyberKnife stereotactic radiosurgery for the treatment of symptomatic vertebral hemangiomas: a single-institution experience

OBJECTIVE

Symptomatic vertebral hemangiomas (SVHs) are a very rare pathology that can present with persistent pain or neurological deficits that warrant surgical intervention. Given the relative rarity and difficulty in assessment, the authors sought to present a dedicated series of SVHs treated using stereotactic radiosurgery (SRS) to provide insight into clinical decision making.

METHODS

A retrospective review of a single institution's experience with hypofractionated radiosurgery for SVH from 2004 to 2011 was conducted to determine the clinical and radiographic outcomes following SRS treatment. The authors report and analyze the treatment course of 5 patients with 7 lesions, 2 of which were treated primarily by SRS.

RESULTS

Of the 5 patients studied, 4 presented with a chief complaint of pain refractory to conservative measures. Three patients reported dysesthesias, and 2 reported upper-extremity weakness. Following radiosurgery, 4 of 5 patients exhibited improvement in their primary symptoms (3 for pain and 1 for weakness), achieving a clinical response after a mean period of 1 year. In 2 cases there was 20%–40% reduction in lesion size in the most responsive dimension as noted on images. All treatments were well tolerated.

CONCLUSIONS

SRS for SVH is a safe and feasible treatment strategy, comparable to prior radiotherapy studies, and in select cases may successfully confer delayed decompressive effects. Additional investigation will determine future patient selection and how conformal SRS treatment can best be administered.

Treatment of cerebral cavernous malformations: a systematic review and meta-regression analysis

OBJECTIVE

The reported effects of treating cerebral cavernous malformations (CCMs) by neurosurgical excision or stereotactic radiosurgery are imprecise and vary between studies.

METHODS

We searched Ovid Medline, EMBASE and The Cochrane Library for peer-reviewed publications of cohort studies describing outcomes of treating 20 or more patients with CCM with at least 80% completeness of follow-up. Two reviewers extracted data to quantify the incidence of a composite outcome (death, non-fatal intracranial haemorrhage, or new/worse persistent focal neurological deficit) after CCM treatment. We explored associations between summary measures of study characteristics and outcome using Poisson meta-regression analyses.

RESULTS

We included 63 cohorts, involving 3424 patients. The incidence of the composite outcome was 6.6 (95% CI 5.7 to 7.5) per 100 person-years after neurosurgical excision (median follow-up 3.3 years) and 5.4 (95% CI 4.5 to 6.4) after stereotactic radiosurgery (median follow-up 4.1 years). After neurosurgical excision the incidence of the composite outcome increased with every per cent point increase in patients with brainstem CCM (rate ratio (RR) 1.03, 95% CI 1.01 to 1.05), and decreased with each more recent study midyear (RR 0.91, 95% CI 0.85 to 0.98) and each per cent point increase in patients presenting with haemorrhage (RR 0.98, 95% CI 0.96 to 1.00). We did not find significant associations in studies of stereotactic radiosurgery.

CONCLUSIONS

The reported risks of CCM treatment (and the lower risks of neurosurgical excision over time, from recently bled CCMs, and for CCMs outside the brainstem) compare favourably with the risks of recurrent haemorrhage from CCM. Long-term effects, especially important for stereotactic radiosurgery, are unknown.

Evaluation of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) for cerebral cavernous malformations: a 15-year single-center experience

BACKGROUND AND OBJECTIVES

Surgery is the principal treatment for safely accessible hemorrhagic and symptomatic cavernous malformations. Nevertheless, the role of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) in the management of high-risk, symptomatic cavernoma lesions warrants further refinement. In this study, we evaluate the use of LINAC-based SRS for cerebral cavernous malformations (CMs) and report our 15-year single-center experience.

DESIGN AND SETTINGS

A retrospective study from the Department of Radiation Oncology and the Department of Neurosurgery at Gulhane Military Medical Academy and Medical Faculty, Ankara from April 1998 to June 2013.

PATIENTS AND METHODS

Fifty-two patients (22 females and 30 males) with cerebral CM referred to our department underwent high-precision single-dose SRS using a LINAC with 6-MV photons. All patients had at least 1 bleeding episode prior to radiosurgery along with related symptoms. Median dose prescribed to the 85% to 95% isodose line encompassing the target volume was 15 Gy (range, 10-20).

RESULTS

Out of the total 52 patients, follow-up data were available for 47 patients (90.4%). Median age was 35 years (range, 19-63). Median follow-up time was 5.17 years (range, 0.08-9.5) after SRS. Three hemorrhages were identified in the post-SRS period. Statistically significant decrease was observed in the annual hemorrhage rate after radiosurgical treatment (pre-SRS 39% vs post-SRS 1.21, P < .0001). Overall, there were no radiosurgery-related complications resulting in mortality.

CONCLUSION

LINAC-based SRS may be considered as a treatment option for high-risk, symptomatic cerebral CM of selected patients with prior bleeding from lesions located at surgically inaccessible or eloquent brain areas.

Stereotactic radiosurgery of intracranial cavernous malformations

Despite increasing worldwide experience, the role of stereotactic radiosurgery (SRS) in the management of cerebral cavernous malformations (CMs) remains controversial. Microsurgical excision of easily accessible CMs is typically safe; therefore, removal remains the gold standard for most of the symptomatic hemispheric lesions. However, there is now sufficient evidence supporting the use of SRS for the difficult cases. Waiting for the cumulative morbidity of the natural history to justify intervention does not serve the patient's interest, therefore, we argue for early radiosurgical intervention. Carefully designed randomized controlled trials might resolve controversies concerning the role of SRS in treating cerebral CMs.

Gamma knife surgery for a hemangioma of the cavernous sinus in a child

Cavernous sinus (CS) hemangiomas are rare vascular abnormalities that constitute 0.4%-2% of all lesions within the CS. Cavernous sinus hemangiomas are high-flow vascular tumors that tend to hemorrhage profusely during resection, leading to incomplete resection and high morbidity and mortality. While Gamma Knife surgery (GKS) has proven to be an effective treatment of CS hemangiomas in the adult population, few reports of GKS for treatment of CS hemangiomas exist in the pediatric literature. Here, the authors present the first case of a 15-year-old girl with a biopsy-proven CS hemangioma who achieved complete resolution of her symptoms and a complete imaging-defined response following GKS. If suspicion for a CS hemangioma is high in a pediatric patient, GKS may be considered as an effective treatment modality, thus avoiding the morbidities of open resection.

Surgical treatment of symptomatic cerebral cavernous malformations in eloquent brain regions

BACKGROUND

Despite the increased risk of hemorrhage and deteriorating neurological function of once-bled cerebral cavernous malformations (CM), the management of eloquently located CMs remains controversial.

METHODS

All eloquently located CMs (n = 45) surgically treated between 03/2006 and 04/2011 in our department were consecutively evaluated. Eloquence was characterized according to Spetzler and Martin's definition. The following locations were approached: brainstem, n = 16; sensorimotor, n = 8; visual pathway, n = 7; cerebellum (deep nuclei and peduncles), n = 7; basal ganglia, n = 4, and language, n = 3. Follow-up data was available for 41 patients (91 %) with a median interval of 14 months. Outcomes were evaluated according to the Glasgow outcome and the modified Rankin scale.

RESULTS

Immediately after surgery, 47 % (n = 21) had a new deficit. At follow-up, 80 % (n = 36) recovered to at least preoperative status or were better than before surgery, 9 % (n = 4) exhibited a slight, and 7 % (n = 3) had a moderate neurological impairment. Only two cases (4 %) with a new permanent severe deficit were observed, both related to dorsal brainstem surgery. The outcome after the surgery of otherwise located brainstem CMs was as beneficial as that for non-brainstem CMs. Patients with initially poor neurological performance fared worse than oligosymptomatic patients.

CONCLUSIONS

Despite the high postoperative transient morbidity, the majority improved profoundly during follow-ups. Compared with natural history, surgical treatment should be considered for all eloquent symptomatic CMs. Dorsal brainstem location and poor preoperative neurological status are associated with an increased postoperative morbidity.

Stereotactic LINAC radiosurgery for the treatment of brainstem cavernomas

BACKGROUND

The management of deep-seated cerebral cavernous malformations (CCMs) is still controversial. Although surgery remains the treatment of choice in patients with recurrent hemorrhage, patients with CCMs located in the brainstem are in many cases not eligible for resection due to high procedure-related morbidity and mortality. We evaluated the long-term outcome of LINAC radiosurgery (LINAC-RS) for the treatment of brainstem CCMs.

PATIENTS AND METHODS

Between December 1992 and March 2008, 14 patients (6 men, 8 women) harboring brainstem CCMs underwent LINAC-RS. Pretreatment neuroimaging showed no associated developmental venous angiomas (DVAs) in any of our patients. Prior to treatment, all patients suffered at least from one symptomatic hemorrhage (median 1.8, range 1–3). A median follow-up of 7.1 years (range 2.0–16.8 years) could be obtained in 12 patients. We applied a median tumor surface dose of 13.9 Gy (range 11–18 Gy; median tumor volume 1.6 ml, range 0.4–4.3 ml).

RESULTS

Following LINAC-RS, neurological outcome improved in 4 (33.3%) and remained unchanged in 8 patients (66.7%). Rebleeding with subsequent transient neurological status deterioration occurred in 4 patients (33.3%), leading to additional surgical resection in 2 patients (16.7%). The corresponding annual hemorrhage rate was 4.8% (4/82.8 patient–years). Adverse radiation effects (ARE, defined by perilesional hyperintensity on T2-weighted MR images) were revealed in 3 patients (25%), leading to transient neurological deficits in 2 patients (16.7%). There were no procedure-related complications leading to either permanent morbidity or mortality.

CONCLUSION

Our results support the role of LINAC-RS as an efficient and safe treatment to significantly reduce the annual hemorrhage rate in patients suffering from brainstem CCMs not eligible to microsurgery. Compared with radiosurgery for arteriovenous malformations (AVMs), the intervention-related morbidity is higher.

Stereotactic radiosurgery for deep-seated cavernous malformations: a move toward more active, early intervention. Clinical article

OBJECT

The role of radiosurgery in the treatment of cavernous malformations (CMs) remains controversial. It is frequently recommended only for inoperable lesions that have bled at least twice. Rehemorrhage can carry a substantial risk of morbidity, however. The authors reviewed their practice of treating deep-seated inoperable CMs to assess the complication rate of radiosurgery, the impact that radiosurgery might have on rebleeding, and whether a more active, earlier intervention is justified in managing this condition.

METHODS

The authors performed a retrospective analysis of 113 patients with 79 brainstem and 39 thalamic/basal ganglia CMs treated with Gamma Knife surgery. Lesions were stratified into 2 groups: those that might be lower risk with no more than 1 symptomatic bleed before radiosurgical treatment and those deemed high risk with multiple symptomatic hemorrhages before treatment.

RESULTS

Forty-one CMs had multiple symptomatic hemorrhages before radiosurgery with a first-ever bleed rate of 2.9% per lesion per year, a rebleed rate of 30.5% per lesion per year, and a median time of 1.5 years between the first and second bleeds. In this group the rebleed rate decreased to 15% for the first 2 years after radiosurgery and declined further to 2.4% thereafter. Pretreatment multiple bleeds led to persistent deficits in 72% of the patients. Seventy-seven CMs had no more than 1 symptomatic bleed before radiosurgery, making for a lifetime bleed rate of 2.2% per lesion per year. The short period between the presenting bleed and treatment (median 1 year) makes the natural history in this group uncertain. The rate of hemorrhage in the first 2 years after treatment was 5.1%, and 1.3% thereafter. Pretreatment hemorrhages resulted in permanent deficits in 43% of the patients in this group, a rate significantly lower than in the multiple-bleeds group (p < 0.001). Posttreatment hemorrhages led to persistent deficits in only 7.3% of the patients. Permanent adverse radiation effects were rare (7.3%) and minor in both groups.

CONCLUSIONS

Stereotactic radiosurgery is a safe management strategy for CMs in eloquent sites with the marked advantage of reducing rebleed risks in patients with repeated pretreatment hemorrhages. The benefit in treating CMs with a single bleed is less clear. Note, however, that repeated hemorrhage carries a significant risk of increased morbidity far in excess of any radiosurgery-related morbidity, and the authors assert that this finding justifies the early active management of deep-seated CMs.

Anterior transpetrosal and subtemporal transtentorial approaches for pontine cavernomas

OBJECTIVE

Pontine cavernomas are benign vascular lesions whose surgical treatment is challenging due to their localization. We report our experience in the surgical management of these lesions exclusively using a lateral, subtemporal transtentorial approach in high pontine lesions and an anterior petrosal approach in low pontine lesions.

METHODS

We performed a retrospective study on a series of patients who were operated on for a pontine cavernoma in our neurosurgery department between 1987 and 2007. In the study, we detail the patients' clinical and preoperative radiological data and compare the two surgical techniques we used. Finally, we analyze the postoperative follow-up, the morbidity encountered according to the surgical approach used, and the long-term outcomes.

RESULTS

We enrolled nine patients into the study. Six patients were operated on using an anterior petrosal approach. None of the patients died. Five patients were able to resume their former professional activity after surgery and were clearly improved following surgery. One patient was worse after surgery (hemiplegia and deafness). We used a subtemporal transtentorial approach in three of the patients. None of the patients died. Two of the patients were able to resume their prior professional activities without any sequels, and the third patient's condition worsened following surgery (temporal hematoma).

CONCLUSION

The lateral surgical approach for pontine cavernomas constitutes a reasonable surgical alternative to the transventricular, suboccipital, retromastoid, or transclival approaches. Patient morbidity in both approaches is acceptable, and the long-term outcome is satisfactory with respect to sequels and the resumption of prior professional activity.

Magnetic resonance diffusion tensor imaging and tractography of intracranial cavernous malformations: preliminary observations and characterization of the hemosiderin rim

OBJECT

Cavernous malformations (CMs) can cause symptoms that appear out of proportion to the lesion size, leading one to hypothesize that they may have an effect on adjacent white matter that is not fully explained by local mass effect. The goal of this study was to investigate the diffusion tensor (DT) properties of CMs, the hemosiderin rim, and normal-appearing adjacent white matter.

METHODS

Eighteen cavernous malformations were characterized using standard MR imaging sequences as well as 6-direction DT imaging with single-shot echo planar-gradient echo imaging at 3 tesla.

RESULTS

Diffusion tensor imaging demonstrated that CMs have a characteristic signature on DT imaging, with low fractional anisotropy (FA) and high mean diffusivity centrally within the lesion. The hemosiderin rim had a high FA value relative to the central lesion or adjacent white matter. Tractography revealed that tracts neatly deviate around CMs. Tracts were typically seen to pass through the hemosiderin rim.

CONCLUSIONS

The hemosiderin rim of CMs was intimately associated with white matter tracts that were deviated by the central lesion. These findings are consistent with histopathological reports that the hemosiderin rim is composed of blood breakdown products deposited in viable white matter.

Surgical treatment of brainstem cavernous malformations

BACKGROUND

The contemporary neurosurgeon is often confronted by cavernous malformations. Those located in the brainstem are particularly challenging

METHODS

This article reviews published series on the natural history and surgical outcomes of these lesions and discusses the surgical approaches used at our institution for their resection.

RESULTS

Despite their challenging location in the brainstem, appropriately selected lesions can be resected surgically with acceptable rates of morbidity and mortality.

CONCLUSIONS

Our institutional philosophy on the surgical treatment of brainstem cavernous malformations reflects the substantial surgical experience of the senior author.

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.

[Role of radiosurgery in the management of intracranial cavernomas. Review of the literature]

From a review of the literature dealing with radiosurgery of cavernous malformations, we have analyzed its impact on hemorrhagic risk, epilepsy, histological modifications, morbidity and potential indications of treatment. Radiosurgery could significantly reduce the hemorrhagic risk, in a selected population with a high risk of hemorrhage, after an interval of about 2 years, but cannot provide protection against rebleeding. As for epilepsy related to the lesion, a significant reduction of seizures has been observed in certain cases, with better control in case of recent evolution and simple seizures linked to the site of the vascular malformation. Histologic lesions are vascular fibrosis, fibrinoid necrosis and ferrugination, without good correlation with results of CT scan or MRI. Morbidity of radiosurgery seems higher compared to other diseases with similar doses and target volumes. The rate of transient complications was about 25%, with permanent sequelae in 5 to 10% of patients. This would be due to a radiosensitizing effect of the hemosiderin halo around the lesion. Radiosurgery can be proposed for non-surgical lesions with a high risk of hemorrhage, nevertheless the superiority of the technique over conservative treatment has to be proven. Without long-term prospective studies, the efficiency of RS for cavernomas remains questionable and subject to debate. New imaging methods proving the obstruction of the cavernous malformation are needed.

LINAC radiosurgery for intracranial cavernous malformation: 10-year experience

BACKGROUND

The annual hemorrhage rate of intracranial cavernous malformation (CM) is reported to range from 0.23% to 1.1%. Because of the low hemorrhage rate, operating on a deep symptomatic lesion with or without hemorrhage is considered controversial. For the prevention of hemorrhage, radiosurgery is an alternative method, targeting smaller lesions and delivering higher doses of radiation. Linear accelerator (LINAC) radiosurgery, aside from the gamma knife (GK), is not often discussed in the treatment of CM.

PATIENTS AND METHODS

From 1995 to 2005, 30 patients presenting with hemorrhage or seizures, aged 14-79 years (mean 24.0 years) with single (27 patients) or multiple (three patients) CMs received LINAC radiosurgery at our institute. Six patients received LINAC radiosurgery following craniotomy for residual lesions revealed by the follow-up MRI. The temporal lobe was the most common site for CM in this series (n=8), followed by the brain stem (n=7). Thirty patients received 34 radiosurgery treatments with peripheral doses ranging from 800 cGy to 2200 cGy. The mean follow-up time was 59.9 months (range 1-122 months).

RESULTS

One patient re-bled post-radiosurgery (0.67% in 149.75 observation-years). Two patients had asymptomatic post-LINAC edema (6.7%). Those three patients were symptom-free during the follow-up period.

CONCLUSION

We suggest that LINAC radiosurgery is a relatively safe technique for treating deep or residual CM, although the actual effectiveness for CM obliteration is not known.

Radiosurgery for epilepsy

Radiosurgery is an emerging therapeutic approach for the treatment of medically intractable epileptogenic foci. A favourable seizure outcome was first reported in studies of the effects of radiosurgery in the treatment of arteriovenous malformations and tumours. Radiosurgery has since been applied to the treatment of complex partial seizures with mesial-temporal-lobe onset. Nearly simultaneously, experimental evidence supporting the usefulness of radiosurgery to improve or abolish seizures has confirmed that stereotactic irradiation can preferentially affect epileptogenic versus normal cortex. Further work is clearly needed, but this technique might become an important approach in the management of mesial-temporal and extratemporal epilepsy, especially if refractory seizures arise from eloquent cortex or surgically challenging regions of brain.