Hemicraniectomy Is Safe for Older Stroke Patients

Daniel M. Keller, PhD

October 31, 2012

BRASILIA, Brazil — Despite hemicraniectomy (HC) not being recommended for malignant middle cerebral artery infarction in patients older than 60 years, a new study has shown that it can be performed as safely in this age group as in younger patients.

Lead researcher Saadat Kamran, MD, senior consultant neurologist at Hamad General Hospital in Doha, Qatar, said that for optimal outcomes, it is critical to remove a bone flap of sufficient diameter.

"The diameter of the bone flap or the opening of the middle cranial fossa were the only 2 factors that impacted outcome," Dr. Kamran reported. "Neither age more than 60 or less than 60 or surgery done under or over 48 hours of infarct was significant."

The findings were presented here at the 8th World Stroke Congress (WCS).

Retrospective Review

Malignant cerebral edema has an 80% mortality rate, and HC for decompression reduces mortality, Dr. Kamran said. To test whether it could be efficacious for older patients, he and coworkers did a retrospective review of HC patients from 2005 to 2012, looking for independent predictors of good outcomes.

The cohort younger than 60 years (n = 11) had a mean age of 49 years (range, 31 - 59 years), and the older cohort (n = 5) had a mean age of 64 years (range, 61 - 74 years). All patients had signs of brain herniation, and the groups were similar for several other clinical parameters, including mean infarct volume (368.4 mL vs 371.5 mL, respectively; P = .58).

The mean time from herniation to HC was 3.24 hours for the under-60 age group and 6.94 hours for patients older than 60 years. HC occurred less than 48 hours after infarct for 7 of 11 in the younger cohort but in only 1 of the 5 in the older cohort.

The mean diameter of bone flap removed was 12 cm for the younger patients and 10.3 cm for the older ones. Just 4 of 11 younger patients had less than 12 cm removed, whereas the bone flap was less than 12 cm for all of the older patients. The middle cranial fossa was opened in 7 of the 11 younger ones but in none of the older ones.

At 6 months, 7 of 11 younger patients had modified Rankin Scale (mRS) values of 4 or less (the rest being 5 or greater). Two of 5 older patients had mRS scores of 4 or less, with 3 patient having an mRS of 5 or greater.

Factors Affecting Outcome

Removing a bone flap greater than 12 cm in diameter positively affected outcome, as did opening the wall of the middle cranial fossa (both P < .005). As with age, the final infarct volume, preoperative Glasgow Coma Scale score, target osmolarity achieved, or size of the herniation also did not affect outcome.

There was 1 postoperative complication in the younger cohort and 2 in the older cohort. The 3 complications were a case of pneumonia and 2 urinary tract infections.

Dr. Kamran concluded that selected patients older than 60 years can do well after HC, comparable to younger patients. He said that in his study, there was a trend toward less aggressive and delayed surgery for the older cohort.

Session moderator Joseph Broderick, MD, professor and chair of the Department of Neurology at the University of Cincinnati Neuroscience Institute in Ohio, commented to Medscape Medical News that HC is not a new approach, but what this study shows is that the size of the skull flap is critical.

"So if you're going to decide to do hemicraniectomy in the appropriate group of patients, you've got to take a big enough skull flap out to allow the brain to decompress, and doing a smaller flap is probably not going to be helpful," he said. "You're not allowing the brain to basically have enough space, and then you get almost a herniation syndrome."

The study received no commercial funding. Dr. Kamran has disclosed no relevant financial relationships. Dr. Broderick, who did not participate in the study, has disclosed no relevant financial relationships.

8th World Stroke Congress (WCS). Abstract 593. Presented October 11, 2012.