[Third ventricle width measured by transcranial ultrasound and its diagnostic value in patients with Alzheimer's disease].

Objective: To explore the diagnostic value of third ventricle width (TVW) measured by transcranial ultrasound (TCS) in the clinical diagnosis of Alzheimer's disease (AD) by analyzing and comparing the image characteristics of TVW in AD patients and healthy controls, and its correlation with cranial magnetic resonance medial temporal lobe atrophy (MTA) visual score and neuropsychological characteristics. Methods: TCS examination, MTA score and neuropsychological tests were performed in 39 confirmed AD and 41 normal controls from the Second Affiliated Hospital of Soochow University between January and July 2021. The correlation of TVW with MTA score and neuropsychological characteristics was analyzed and compared between the two groups. Results: A total of thirty-nine AD patients were enrolled, with 28 males and 11 females, aged (73±9) years, including 18 mild, 20 moderate, and 1 severe AD patient. Meanwhile, 41 healthy controls were also included, with 24 males and 17 females, aged (69±6) years old. TVW in AD patients was significantly wider than that in normal controls [0.76(0.66, 0.87) cm vs 0.50(0.44, 0.56) cm, P<0.001]. In neuropsychological tests, compared with normal controls, AD patients showed impaired performances in several cognitive functions, and there were statistically significant differences in delayed memory [0(0, 0) vs 4.0(4.0, 5.0), P<0.001], naming [2.0(1.0, 3.0) vs 3.0(2.0, 3.0), P<0.001], executive function [2.0(2.0, 3.0) vs 3.0(2.5, 3.0), P<0.001], language [0.0(0.0, 2.0) vs 3.0(2.0, 3.0), P<0.001] and other aspects between AD patients and normal controls (all P<0.05). TVW was negatively correlated with immediate memory (r=-0.339, P=0.035), delayed recall (r=-0.523, P<0.001), attention and computing power (r=-0.409, P=0.045), visual space and executive function (r=-0.333, P=0.039), but positively correlated with the atrophy of the medial temporal lobe (r= 0.552, P<0.001). Conclusions: TCS can be used to measure TVW in AD patients. When combined with MTA score and neuropsychological tests, it can provide a reliable objective basis for the clinical diagnosis of AD.