gms | German Medical Science

Objective: Generally, ventricular size in patients after craniectomy is estimated by CCT. Frequent CT scans generate high radiation exposure and are time consuming in ICU patients. At bedside Duplex sonography could be an alternative. However, measurement of ventricular size or parenchymal abnormalities by ultrasound is rarely performed and the reliability of this technique has not been evaluated. Due to the improved sonographic technology visualization of cerebral arteries, veins, parenchyma, ventricular system and their abnormalities became possible. The aim of the study is to compare data of measurements of the ventricular size by ultrasound and CCT in patients after craniectomy.

Method: Out of a series of 88 consecutive evaluated patients we report here the data of the 23 patients evaluated with the Hitachi Sono MR EUB 7500 (Convex probe 5-2; 1.4 MHz) over the craniectomized hemisphere. Documentation of anatomic structures of both hemispheres such as parenchymal appearance, extravascular blood accumulation, hygroma, ventricular diameter, midline shift, and basal vessels was done. Data of ventricular diameter were correlated with measurements obtained by CCT.

Results: The correlation of the diameter of the between ultrasound measurement and CCT was high (correlation coefficient 0,83 for the first and 0.96 for subsequent measurements). In repetitive ultrasound measurements over a few days the stability of the values was good. Midline shifts were detected with good reliability. Alteration of the body position between zero and 45 degrees did not affect the diameter of the ventricles. Large aneurysms could be detected.

Conclusions: Bedside ultrasound measurements of the ventricular size in patients with craniectomy deliver reliable quantitative results for clinical decisions and may reduce the need for repetitive postoperative CT scans.