gms | German Medical Science

Objective: Measurement of ventricular width is important in pediatric patients with hydrocephalus. At the present it is assessed using cranial MRI or CT which involves risks of anesthesia in small children or radiation. As the third ventricle is accessible via the temporal bone window using ultrasound, measurement of its diameter could be a reliable and radiation-free alternative to assess ventricular changes. A necessary precondition is that changes of third ventricle diameter (TVD) correlate witrh changes of the whole ventricular system. In this study TVD was compared to standard ventricular indices to investigate its correlation.

Methods: 394 MRT/CT images from 117 pediatric patients (median age 6.5 years) with hydrocephalus were measured at the time of diagnosis and during acute and chronic changes. Measurements included axial TVD and three standard measurements of the lateral ventricles (Evans Index, FOHR and Cella Media Index (CMI)). TVD and lateral ventricle measurements were compared using Spearman’s and Pearson correlation coefficient at the time of diagnosis, therapy and acute shunt dysfunction. Furthermore, a correlation within subjects was calculated in 8 patients.

Results: The best linear correlation was found between TVD and CMI after initial therapy (r=0.7), at acute shunt dysfunction (R=0.702) and after shunt revision (r=0.566). After shunt revision changes of TVD correlated well with changes in Evans (r= 0.609), FOHR (r=0.74),p < 0.01. The correlation within subjects were outstanding Evans Index (r=0.988), FOHR Index (=0.99) and CMI (0.99).

Conclusion: TVD showed a significant correlation with all lateral ventricle indices at the time of diagnosis, therapy, shunt dysfunction and during chronic changes. It is therefore an excellent mirror of ventricular changes in pediatric hydrocephalus. Thus TVD measurements by ultrasound can potentially substitute standard imaging to asses changes in ventricular width.