V 395
20-MHz-Ultrasound of lacrimal drainage system
F. Tost, R. Bruder, S. Clemens
Purpose: In clinical practice, ultrasound examination of the lacrimal drainage system was not able to represent the lacrimal canaliculi in a high quality. The high-resolution ultrasound with 20-MHz-transducer it is better possible to get images of the lacrimal canaliculi.
Methods: 20 patients suffering from diseases of lacrimal drainage system were examined ultrasonographic. Detection and localization of lacrimal canaliculi was made by 20-MHz-sectorscanner in combination with an ultrasound diagnostic system I3. After the patient positioning, the high-resolution ultrasound investigation followed through immersion connection (methylcellulose). Instillation of viscoelastic substances (Healon®) was necessary by detecting the lacrimal canaliculi.
Results: In all investigated patients, the high-resolution ultrasound (transducer frequency of 20 MHz) allowed reproducible images of the lacrimal drainage system. In addition, it detected parts of vascular network that the lacrimal canaliculi. Without viscoelastic substances, a good echografic visibility of canaliculi structures was obtained from patients with chronic canaliculitis or dislocated punctum plugs. The ultrasonic images showed in chronic canaliculitis an ectatic canaliculus (diverticulum) and high-reflective structures (concrements).
Discussion: The high-resolution ultrasound (transducer frequency of 20 MHz) seems well suited for investigations of the lacrimal drainage system. In comparison with ultrasound biomicroscopy the resolution of the former is lower, but the depth of penetration is higher. The use 20-MHz ultrasonic examination can be helpful in clinical diagnostic of chronic canaliculitis.
Augenklinik, Ernst-Moritz-Arndt-Universität, Rubenow-Str. 2, D 17487 Greifswald