JMIR Publications

ABSTRACT

Background:

The slit lamp biomicroscope is a fundamental diagnostic tool in ophthalmology and optometry. It is used for detailed examination of the eye with stereoscopic visualization. Current camera-equipped digital slit lamps are often designed with a single optical channel, which results in the loss of depth information. Without depth perception, it can be challenging to visualize subtle anatomical variations and perform procedures guided by the slit lamp view. In teleophthalmology applications, 3D slit lamp view is not available, making remote participants have different experiences from directly viewing through a slit lamp.

Objective:

To demonstrate the concept of Mixed Reality–based slit lamp (MR-SLP) capable of displaying real-time stereoscopic view of the slit lamp both locally and remotely, enabling stereoscopic teleophthalmology.

Methods:

Two high-resolution video cameras were mounted on the left and right viewing channels of a conventional slit lamp to capture the corresponding diagnostic images, which were transmitted to multiple Mixed Reality (MR) headsets via a broadcast network at 1080p and 30 FPS. The operator viewed the stereoscopic images through the MR headset and operated the slit lamp using the headset’s see-through function. System performance was quantitatively evaluated in terms of spatial resolution, tube-threading test, and real-time remote streaming.

Results:

The measured spatial resolution reached 102 line-pairs/mm at 25× optical magnification. Depth perception was assessed in five participants using a tube-threading task under four conditions. Task performance differed significantly between non-stereoscopic (2D) and direct eyepiece views (P = 0.028, Kruskal–Wallis test), but not between stereoscopic (3D) MR and direct views (P >0.05, Kruskal–Wallis test). In the real-time remote streaming tests across multiple sites, the system achieved stable, low-latency transmission with an average roundtrip time below 40 ms. Participating ophthalmologists reported user experience and image quality comparable to traditional slit lamps, supporting the feasibility of MR-SLP for real-time, high-quality stereoscopic teleophthalmology.

Conclusions:

The MR-SLP can provide real-time stereoscopic slit lamp examination images/videos through a broadcasting network to remote locations. The spatial resolution and depth perception are comparable to direct viewing through the eyepieces of a traditional slit lamp. This study demonstrated the feasibility of MR-SLP for high-quality stereoscopic teleophthalmology.