MR dacryocystography - Optimising a dynamic imaging protocol for patients with epiphora.

INTRODUCTION

Radiological investigations for epiphora often use techniques involving ionising radiation and may require invasive canalicular cannulation. Magnetic resonance dacryocystography (MRDCG) has been explored but is currently not widely utilised in clinical imaging departments. The aim of this technical report is to describe the optimisation of a non-invasive MRDCG technique using a continuous gadolinium drip to assess the anatomy and real-time functionality of the nasolacrimal drainage system (NLDS).

METHODS

A protocol was developed on a 1.5 Tesla (1.5 T) magnetic resonance imaging (MRI) scanner using a 32-channel head coil. Coronal and axial T2-weighted sequences demonstrated the anatomy of the NLDS region. An automated slow drip infusion of gadolinium contrast media, diluted with saline (1:100), was delivered simultaneously to both eyes during a two-dimensional (2D) dynamic acquisition. Post-instillation, a three-dimensional (3D) T1-weighted sequence confirmed the presence or absence of contrast media in the NLDS.

RESULTS

Clear visualisation of the anatomy and real-time contrast flow through the NLDS were achieved in 85 % of cases.

CONCLUSION

This non-invasive MRDCG technique can provide both anatomical and functional evaluation of the NLDS in under 30 minutes. Further work is needed to compare MRDCG findings to more established methods such as DCG and DSG.