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

Abstract

Object The aim of this study was to evaluate the pre- and postoperative rehemorrhage risk, neurological function outcome, and prognostic factors of surgically treated brainstem cavernous malformations (CMs) with long-term follow-up. Methods The authors conducted a retrospective review of the clinical data from 242 patients with brainstem CMs that were surgically treated between 1999 and 2010. Patient charts, imaging findings, and outcomes were examined. Results The study included 242 patients, with a male-to-female ratio of 1.3 and mean age of 32.6 years. The mean modified Rankin Scale scores on admission, at discharge, at 3 and 6 months after surgery, and at recent evaluation were 2.2, 2.6, 2.3, 1.8, and 1.5, respectively. The preoperative calculated annual hemorrhage and rehemorrhage rates were 5.0% and 60.9%, respectively. The complete resection rate was 95%. Surgical morbidity occurred in 112 patients (46.3%). Eighty-five patients (35.1%) demonstrated worsened condition immediately after surgery; 34 (41.0%) and 51 (61.4%) of these patients recovered to their baseline level within 3 and 6 months after surgery, respectively. At a mean follow-up of 89.4 months, the patients' condition had improved in 147 cases (60.7%), was unchanged in 70 cases (28.9%), and had worsened in 25 cases (10.3%). A total of 8 hemorrhages occurred in 6 patients, and the postoperative annual hemorrhage rate was 0.4%. Permanent morbidity remained in 65 patients (26.9%). The adverse factors for preoperative rehemorrhage were age ≥ 50 years, size ≥ 2 cm, and perilesional edema. The risk factors for postoperative hemorrhage were developmental venous anomaly and incomplete resection. The independent adverse factors for long-term outcome were increased age, multiple hemorrhages, ventral-seated lesions, and poor preoperative status. Favorable, complete improvement in the postoperative deficits over time was correlated with good preoperative neurological function and continuing improvement thereafter. Conclusions Favorable long-term outcomes and significantly low postoperative annual hemorrhage rates were achieved via surgery. Total resection should be attempted with an aim of minimal injury to neurological function; however, postoperative deficits can improve during the postoperative course. Close follow-up with radiological examination is proposed for patients with adverse factors predictive of rehemorrhage.

Clinical course of untreated pediatric brainstem cavernous malformations: hemorrhage risk and functional recovery

“…26 The presence of edema was not necessarily associated with lesion size, and we preferred the speculation of the probable invasiveness of the lesions and the infiltrated normal parenchyma. 35 The hemorrhage risk of a larger lesion size in our study was consistent with that of a prior study. 30 It could be inferred that despite the lowpressure lesions, the intralesional pressure would gradually increase along with the lesion size in the limited volume of the brainstem; if the pressure exceeded a critical point, the lesion could rupture, followed by significant clinical changes.…”

“…Furthermore, studies differed in their hemorrhage definitions, the assumption of a congenital lesion, and neurological function evaluation methods. 1,2,4,14,24,30,35 In our study, we performed a prospective analysis of retrospectively collected data on the cohort of pediatric brainstem CMs with a stringent definition of hemorrhage and found that the annual hemorrhage rate was calculated to be 11.7% per patientyear, that both the presence of perilesional edema and a larger lesion size predicted poorer hemorrhagefree survival and a higher annual hemorrhage rate, and that prospective hemorrhage prevented complete neurological recovery (Fig. 2).…”

“…44,50 Initial neuroradiographic characteristics, such as multiple CMs, size, location, perilesional edema, developmental venous anomaly (DVA), side, depth, and others, were reviewed extensively and determined according to previously reported methods (Table 2). 35,36 Lesion size was evaluated as the lesion equivalent diameter (abc) 1/3 , where a, b, and c represent the diameters as measured on axial, sagittal, and coronal MR images, respectively. The depth of the lesion was determined by the parenchyma located between the pial surface and the lesion on T1weighted imaging.…”

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

“…In fact, data from various authors imply that an apparent increased hemorrhage risk of brain stem lesions is likely to be caused by a selection bias: Brain stem hemorrhage is more likely to be symptomatic than supratentorial hemorrhage and is therefore more likely to lead to MR imaging. 9,12,18,19 …”

“…6 Other authors identified prior hemorrhage as an important risk factor for subsequent hemorrhage by comparing hemorrhage rates of CCMs with and without prior hemorrhage. 1,2,5,[7][8][9] According to these studies, hemorrhage rates ranged from 0%-6% and 4.5%-60%, depending on whether prior hemorrhage was or was not present, respectively. 1,2,5,7-9 However, these articles have a lack of comparability because of differing hemorrhage definitions.…”