Air-insufflated high-definition dacryoendoscopy yields significantly better image quality than conventional dacryoendoscopy

Improvement in Dacryoendoscopic Visibility after Image Processing Using Comb-Removal and Image-Sharpening Algorithms

Recently, a minimally invasive treatment for lacrimal passage diseases was developed using dacryoendoscopy. Good visibility of the lacrimal passage is important for examination and treatment. This study aimed to investigate whether image processing can improve the dacryoendoscopic visibility using comb-removal and image-sharpening algorithms. We processed 20 dacryoendoscopic images (original images) using comb-removal and image-sharpening algorithms. Overall, 40 images (20 original and 20 post-processing) were randomly presented to the evaluators, who scored each image on a 10-point scale. The scores of the original and post-processing images were compared statistically. Additionally, in vitro experiments were performed using a test chart to examine whether image processing could improve the dacryoendoscopic visibility in a turbid fluid. The visual score (estimate ± standard error) of the images significantly improved from 3.52 ± 0.26 (original images) to 5.77 ± 0.28 (post-processing images; p < 0.001, linear mixed-effects model). The in vitro experiments revealed that the contrast and resolution of images in the turbid fluid improved after image processing. Image processing with our comb-removal and image-sharpening algorithms improved dacryoendoscopic visibility. The techniques used in this study are applicable for real-time processing and can be easily introduced in clinical practice.

Usefulness of high definition sialoendoscope for evaluation of lacrimal drainage system in congenital nasolacrimal duct obstruction

PURPOSE

Sialoendoscope was used as a dacryoendoscope, high- definition images of the lacrimal drainage system (LDS) were captured and its performance in congenital nasolacrimal duct obstruction (CNLDO) is reported.

METHODS

Nasal endoscopy was done as the first in all the cases using a 0°, 2.7 mm nasal endoscope (Karl Stroz Tutlingan Germany). This was followed by Dacryoendoscopy (DEN) of the lacrimal drainage system from puncta till the valve of Hasner. DEN was performed under general anaesthesia in 26 children (including 17 primary and 9 failed probing cases). All cases were examined using 0.8 mm sialoendoscope (Karl Storz, Tuttlingen, Germany) with fibreoptic light transmission with a side port for irrigation.

RESULTS

We were able to obtain high-definition images of canaliculi, lacrimal sac, sac duct junction, proximal, mid and distal segments of nasolacrimal duct in all the children with CNLDO.In 17 primary cases 16 had distal membranous obstruction and I case had proximal canalicular obstruction. In nine children with history of failed probing, five had membranous obstruction, two had dacryoliths, two had NLD malformation at different levels. An overall success rate of 88.4% was achieved.

CONCLUSION

Sialoendoscope can be used as high-definition dacryoendoscope for diagnostic and therapeutic use in CNLDO. Useful information can be obtained on dacryoendoscopy in complex CNLDO cases.

Utility of intraocular endoscope for lacrimal canaliculi and sac examination

PURPOSE

Intraocular endoscope was used as a dacryoendoscope, and its observations and performance in lacrimal drainage system (LDS) are reported.

METHODS

The Endo Optiks (Little Silver, New Jersey, USA), an intraocular endoscope (modified with customized sheath), was used for LDS visualization in ten normal adults and five patients with lacrimal disorders.

RESULTS

We were able to capture high-definition images of lacrimal canaliculi and sac in all normal adults. Smooth whitish canalicular mucosa with lumen could be appreciated in all normal individuals. Common canaliculus showed variable folds among individuals and reddish lacrimal sac mucosa could be appreciated with great details. In patients with canalicular obstruction, site of obstruction was presented as whitish gray area with no visible lumen, which could be opened up precisely with trephination. No false passage was formed in any of the cases. One of the cases had membranous canalicular obstruction, which was opened with probe itself. Nasolacrimal duct could not be examined due to the shorter length of the probe.

CONCLUSION

Intraocular endoscope can be used as high-resolution dacryoendoscope for visualization of lacrimal canaliculi and sac.