Optimised low-dose multidetector CT protocol for children with cranial deformity

Abstract

Objective: To present an optimised low-dose multidetector computed tomography (MDCT) protocol for the study of children with cranial deformity.

Methods: Ninety-one consecutive MDCT studies were performed in 80 children. Studies were performed with either our standard head CT protocol (group 1, n = 20) or a low-dose cranial deformity protocol (groups 2 and 3). Group 2 (n = 38), initial, and group 3 (n = 33), final and more optimised. All studies were performed in the same 64-MDCT equipment. Cranial deformity protocol was gradationally optimised decreasing kVp, limiting mA range, using automatic exposure control (AEC) and increasing the noise index (NI). Image quality was assessed. Dose indicators such us CT dose index volume (CTDIvol), dose-length product (DLP) and effective dose (E) were used.

Results: The optimised low-dose protocol reached the following values: 80 kVp, mA range: 50-150 and NI = 23. We achieved a maximum dose reduction of 10-22 times in the 1- to 12-month-old cranium in regard to the 2004 European guidelines for MDCT.

Conclusion: A low-dose MDCT protocol that may be used as the first diagnostic imaging option in clinically selected patients with skull abnormalities.

Key points: • MDCT is a very useful tool in the study of skull lesions • Low-dose MDCT minimises child exposure to ionising radiation while maintaining image quality • Low-dose MDCT should be considered as the first imaging option in selected patients.