Polisomnographyc results in chiari malformation type I

Abstract

The most common symptom experienced by patients with Chiari I malformation (CM-I) is occipital headache many times started or worsened by Valsalva maneuvers a sneezing, coughing, or straining. They may also experience difficulties with balancing and dizziness, muscle weakness, coordination problems, as well as gait abnormalities. Some patients present with sleep disordered breathing a symptoms such as hypersomnia, insomnia or sleep disorder breathing. Although several authors have found distinct types of apneas and hypopneas in patients with CM-I, there are no studies that analyze sleep quality with this malformation. The main purpose of this study is to establish the impact of CM-I on sleep architecture, respiratory parameters and leg movements (PLMs). A prospective study was conducted in a correlative series of 105 CM-I patients (67 women and 38 men, mean age of 41.9 ± 12.5 years) admitted between 10/1997 and 04/2001. A whole-night video-polysomnography was performed in all patients. Sleepiness in pathological range (Epworth > 10) was present in only 12 patients (11.4%). Sleep architecture only showed a decrease in sleep efficiency due to wake after sleep onset with preservation in normal range of sleep stages proportions. Fifty-three patients showed a pathological respiratory disturbance index (RDI Y5) and in 29.5% moderate to severe range (RDIY15). The respiratory alterations were predominantly obstructive hypopneas during the supine position. Twenty-two patients showed PLMs > 15. Patients with CM-I had an increased prevalence of fragmented sleep and sleep disordered breathing respect to normal population. These alterations may not be reported by patients and can only be detected by performing a specific sleep study. Its detection may help to screen patients and to establish surgical indications.. This work has been supported in part by the Fondo de Investigación Sanitaria (Instituto de Salud Carlos III) with grant PI07/0681, co-financed by the European Regional Development Fund (ERDF) and awarded to Dr. M.A. Poca.