Henicraniectomy

According to researchers, amongst stroke patients older than 60 with life-threatening brain edema, henicraniectomy cut the mortality rate by more than half compared with conservative treatment.  The 6-month survival rate without severe disability was 38% in the surgery group, compared to 18% among controls in a 112-patient randomized trial called DESTINY II, according to Werner Hacke, of the University of Heidelberg in Germany.  Overall 6-month survival was 70% with hemicreniectomy patients, as opposed to 33% of those treated conservatively, according to research in the March 20 issue of the New England Journal of Medicine.  Enrollment stopped early after interim analysis showed that the surgery significantly improved survival.

henicraniectomy

A henicraniectomy in progress.

The trial is the first to focus on older recipient of the procedure, in which about one-quarter of the skull is removed to relieve pressure on the brain following a stroke.  Earlier research found that it improved outcomes in younger patients, although its efficacy and safety in the main age group subject to strokes remained unclear.  In an accompanying editorial, Allan Ropper of Brigham and Women’s Hospital in Boston pointed out that survival was still not guaranteed after the procedure, and most patients receiving it still had significant disability.  He pointed out that half of the survivors in both treatment groups ended up with modified Rankin scores of 4, while about one-third of them had scores of 5.

According to Ropper, while these outcomes are bracing, they’re about the same with or without the operation, and it can be said that hemicraniectomy doesn’t increase the number of disabled patients.  The study also doesn’t provide support for previous claims that surgery improves functional outcome.  The investigators acknowledged that the improve surgical outcomes were driven almost exclusively by the reduction in mortality, although they also pointed out that most survivors in both groups reported being satisfied with their outcomes.  This led to Ropper commenting that people seemed content to just come out of the surgery alive.

Inclusion criteria for the trial were a diagnosis of acute middle cerebral artery infarction with onset less than 48 hours before treatment, 61 years or older, NIH Stroke Scale scores at recruitment of more than 14 in those with infarction in the nondominant hemisphere or more than 19 when infarction was in the dominant hemisphere and brain imaging results indicating that ischemia had affected at least two-thirds of the brain served by the middle cerebral artery.  Patients with significant pre-existing disabilities, lacking pupillary reflexes, Glasgow Coma Scale scores less than 6, hemorrhages or an estimated life expectancy of less than 3 years were excluded.  The average age of enrolled patients was 70, ranging up to 82, and were equally split between men and women.  Median NIH Stroke Scale scores at enrollment were around 20, with a range of 15 to 40.

A total of 49 subjects were randomized to hemicraniectomy and 63 to conservative treatment.  The latter consisted of usual ICU support with osmotherapy, sedation and ventilation.  hemicraniectomy involved the removal of skull bone at least 12 cm in diameter.  The primary outcome was modified Rankin score at 6 months.  Secondary outcomes included survival, NIH Stroke Scale score, quality of life scores from two instruments, Hamilton Depression Rating Scale score and adverse events such as surgical complications.

After 6 months, amongst those who underwent a hemicraniectomy, there were 6 deaths, 33% who had a 5 Rankin score, 28% with a 4 and 32% with a 3.  In the control group, there were 6 deaths, 70% had a 5 Rankin score, 13% had a 4 and 15% had a 3.  After a full year, an additional 6% of the control patients and 10% of the surgery group were dead.  The proportions of those with Rankin scores of 3 or 4 were about the same as they had been six months earlier.  Secondary outcomes for 1-year survivors were about the same in both groups, with large impairments in quality of life and persistent symptoms.  However, overt depression was rare, with no hemicraniectomy survivors showing Hamilton scores of 20 or higher, and only 17% of controls had scores in that range.

Family members gave consent for participation in the trial.  After the 1-year follow-up, Hacke and his colleagues asked the surviving patients themselves if they would have agreed to participate in the study.  63% of the hemicraniectomy patients and 53% of the controls gave their “retroactive consent” to this.