Duke S. Samson and Babu G. Welch
Joan Margaret O’Donnell, Michael Kerin Morgan and Maurizio Manuguerra
Few studies have examined patients’ ability to drive and quality of life (QOL) after microsurgical repair for unruptured intracranial aneurysms (uIAs). However, without a strong evidentiary basis, jurisdictional road transport authorities have recommended driving restrictions following brain surgery. In the present study, authors examined the outcomes of the microsurgical repair of uIAs by measuring patients’ perceived QOL and cognitive abilities related to driving.
Between January 2011 and January 2016, patients with a new diagnosis of uIA were prospectively enrolled in this study. Assessments were performed at referral, before surgery, and at 6 weeks and 12 months after surgery in those undergoing microsurgical repair and at referral and at 12 months in conservatively managed patients. Assessments included the Physical Component Summary (PCS) and Mental Component Summary (MCS) of the SF-36, the off-road driver-screening instrument DriveSafe (DS), the modified Barthel Index (mBI), and the modified Rankin Scale (mRS).
One hundred sixty-nine patients were enrolled in and completed the study, and 112 (66%) of them had microsurgical repair of their aneurysm. In the microsurgical group, there was a trend for improved DS scores: from a mean (± standard deviation) score of 108 ± 10.7 before surgery to 111 ± 9.7 at 6 weeks after surgery to 112 ± 10.2 at 12 months after surgery (p = 0.05). Two percent of the microsurgical repair group and 4% of the conservatively managed group whose initial scores indicated competency to drive according to the DS test subsequently had 12-month scores deemed as not competent to drive; the difference between these 2 groups was not statistically significant (p > 0.99). Factors associated with a decline in the DS score among those who had a license at the time of initial assessment were an increasing age (p < 0.01) and mRS score > 0 at one of the assessments (initial, 6 weeks, or 12 months; p < 0.01).
Mean PCS scores in the microsurgical repair group were 52 ± 8.1, 46 ± 6.8, and 52 ± 7.1 at the initial, 6-week, and 12-month assessments, respectively (p < 0.01). These values represented a significant decline in the mean PCS score at 6 weeks that recovered by 12 months (p < 0.01). There were no significant changes in the MCS, mBI, or mRS scores in the surgical group.
Overall, QOL at 12 months for the microsurgical repair group had not decreased and was comparable to that in the conservatively managed group. Furthermore, as assessed by the DS test, the majority of patients were not affected in their ability to drive.
Alessandro Della Puppa, Oriela Rustemi and Renato Scienza
Michael Kerin Morgan, Andrew Stewart Davidson, Stavros Koustais, Mary Simons and Elizabeth Anne Ritson
Ethylene-vinyl alcohol copolymer embolization is increasingly used preoperatively in the resection of brain arteriovenous malformations (AVMs). However, the case for embolization improving the outcome of resection has not been evaluated. In this paper the authors set out to compare outcomes after surgery for brain AVMs in 2 consecutive periods of practice. In the first period, selective embolization was used without the use of ethylene-vinyl alcohol copolymer. In the second period, selective embolization with ethylene-vinyl alcohol copolymer was performed.
A consecutive case series (prospectively collected data) was retrospectively analyzed. Adverse outcomes were considered to be an outcome modified Rankin Scale score greater than 2 due to embolization or surgery.
A total of 538 surgical cases were included. The percentages of adverse outcomes were as follows: 0.34% for Spetzler-Martin AVMs less than Grade III (1 of 297 cases); 5.23% (95% CI 2.64%–9.78%) for Grade III AVMs (9 of 172 cases); and 17% (95% CI 10%–28%) for AVMs greater than Grade III (12 of 69 cases). There was no improvement in outcomes from the first period to the second period. The adverse outcome for Grade III brain AVMs in the first period was 5.2% (7 of 135 cases) and in the second period (after ethylene-vinyl alcohol copolymer was introduced) it was 5.4% (2 of 37 cases). For AVMs greater than Grade III, the adverse outcome was 12% (6 of 49 cases) in the first period and 30% (6 of 20 cases) in the second period.
Outcomes for brain AVM surgery were not improved by ethylene-vinyl alcohol copolymer embolization. Preoperative embolization of high-grade AVMs with an ethylene-vinyl alcohol copolymer did not prevent those hemorrhagic complications which embolization is hypothesized to prevent based on theoretical speculations but not demonstrated in practice.
Michael Kerin Morgan, Nirav J. Patel, Mary Simons, Elizabeth Anne Ritson and Gillian Z. Heller
Case reports suggest that young age is a critical factor in determining recurrence of brain arteriovenous malformations (AVMs) after surgery. However, other factors that may contribute to the increased risk of recurrence have not been considered. In this study, the authors' goal was to ascertain the risk and risk factors of recurrence after resection of AVMs of the brain.
A consecutive case series (prospectively collected data) of 600 cases of resection of brain AVMs was retrospectively analyzed. Radiological evidence of recurrence or nonrecurrence, as well as clinical evidence of recurrence, could be established in 427 of these cases that underwent follow-up for more than 350 days after initial surgery. These cases were analyzed using Kaplan-Meier curves and Cox regression with respect to age and the presence of deep venous drainage.
Nine recurrent AVMs were found in 8 patients. By analysis of the Kaplan-Meier curves, the 10-year recurrence rate was 14% for those with deep venous drainage, compared with 4% for those without deep venous drainage. Stratifying by age, in the 0- to 20-year age group, the 10-year recurrence rates were 63% and 13% for those with and without deep venous drainage, respectively. In the 20- to 39-year age group, the rates were 5% and 0% respectively, and in the 40-year and older age group they were 0% and 3%, respectively. The hazard ratio for deep venous drainage, adjusted for age, was 5.97 (95% CI 1.20–29.69, p = 0.029).
The risk of recurrence after AVM resection is significant for young patients with deep venous drainage.
David Bervini, Michael Kerin Morgan, Elizabeth Anne Ritson and Gillian Heller
The aim of this study was to identify patients who are likely to benefit from surgery for unruptured brain arteriovenous malformations (ubAVMs).
The authors' database was interrogated for the risk and outcome of hemorrhage after referral and the outcome from surgery. Furthermore, the outcome from surgery incorporated those cases excluded from surgery because of perceived greater risk (sensitivity analysis). Finally, a comparison was made for the authors' patients between the natural history and surgery. Data were collected for 427 consecutively enrolled patients with ubAVMs in a database that included patients who were conservatively managed. Kaplan-Meier analysis was performed on patients observed for more than 1 day to determine the risk of hemorrhage. Variables that may influence the risk of first hemorrhage were assessed using Cox proportional hazard regression models and Kaplan-Meier life table analyses from referral until the first occurrence of the following: hemorrhage, treatment, or last review. The outcome from surgery (leading to a new permanent neurological deficit with last review modified Rankin Scale [mRS] score > 1) was determined. Further sensitivity analysis was made to predict risk from surgery for the total ubAVM cohort by incorporating outcomes of surgical cases as well as cases excluded from surgery because of perceived risk, and assuming an adverse outcome for these excluded cases.
A total of 377 patients with a ubAVM were included in the analysis of the risk of hemorrhage. The 5-year risk of hemorrhage for ubAVM was 11.5%. Hemorrhage resulted in an mRS score > 1 in 14 cases (88% [95% CI 63%–98%]). Patients with Spetzler-Ponce Class A ubAVMs treated by surgery (n = 190) had a risk from surgery of 1.6% (95% CI 0.3%–4.8%) for a permanent neurological deficit leading to an mRS score > 1 and 0.5% (95% CI < 0.1%–3.2%) for a permanent neurological deficit leading to an mRS score > 2. Patients with Spetzler-Ponce Class B ubAVMs treated by surgery (n = 107) had a risk from surgery of 14.0% (95% CI 8.6%–22.0%) for a permanent neurological deficit leading to an mRS score > 1. Sensitivity analysis of Spetzler-Ponce Class B ubAVMs, including those in patients excluded from surgery, showed that the true risk for surgically eligible patients may have been as high as 15.6% (95% CI 9.9%–23.7%) for mRS score > 1, had all patients who were perceived to have a greater risk experienced an adverse outcome. Patients with Spetzler-Ponce Class C ubAVMs treated by surgery (n = 44) had a risk from surgery of 38.6% (95% CI 25.7%–53.4%) for a permanent neurological deficit leading to an mRS score > 1. Sensitivity analysis of Class C ubAVMs, including those harbored by patients excluded from surgery, showed that the true risk for surgically eligible patients may have been as high as 60.9% (95% CI 49.2%–71.5%) for mRS score > 1, had all patients who were perceived to have a greater risk experienced an adverse outcome.
Surgical outcomes for Spetzler-Ponce Class A ubAVMs are better than those for conservative management.