Objective: To examine the long-term effects of suboccipito-cervical decompression on an intention-to-treat basis in patients with Chiari I malformation (CMI).
Patients and methods: Twenty-four consecutive patients, 14 females and 10 males with a median age of 26 years, underwent decompressive surgery for CMI during 1998-2006. All patients were contacted by an independent examiner and asked to complete a questionnaire regarding headache, other neurological symptoms and negative impact of the disease on the daily life before and after surgery. The median follow-up time after surgery was 3.2 years (range 1.7-9.2 years). Twenty-three patients (96%) completed the questionnaire.
Results: On an intention-to-treat basis there was an improvement in headache in 75%, decreased associated neurological symptoms in 88% and less negative impact on daily life in 75% of the 24-operated patients.
Conclusions: More than three-quarters of the patients still considered their situation improved at long-term follow-up after surgery. These results support surgical intervention in symptomatic Chiari I patients.