Ultrawide Field Imaging in Uveitic Non-dilating Pupils.

PRESENTATION

Non-dilating pupils due to anterior segment inflammation in uveitis commonly interfere with a proper fundus examination. Ultrawide field fundus imaging (UWFI, Optos 200 Tx™; Optos PLC., Dunfermline, Scotland, United Kingdom) uses a confocal scanning laser ophthalmoscope. The aim of this manuscript is to describe the utility of UWFI in cases of uveitis with non-dilating pupils. Consent was taken from all the patients and the declaration of Helsinki was followed during patient care.

A 32-year-old woman (Case 1) had small pupils in both eyes. She had 5/60 vision in both eyes with bilateral early posterior subcapsular cataracts [Figure 1a], and cystoid macular edema. The UWFI enabled us to document the associated vitritis [Figure 1b]. No other retinochoroidal lesion or vasculitis was seen. Thus, a diagnosis of intermediate uveitis was made.

Figure 1

(a) The left eye of Case 1 has a small non-dilating pupil, (b) ultrawide field fundus image of left eye shows vitritis and no other retinochoroidal lesions. This suggests a diagnosis of intermediate uveitis.

A 43-year-old woman (Case 2) with acquired immunodeficiency syndrome and a CD4 count of 33 presented with bilateral perception of light and inaccurate projection of rays. Both eyes had posterior synechiae, right eye had an early cataract [Figure 2a] and left eye had a mature cataract. Further, UWFI of the right eye revealed a retinal detachment with a large posterior retinal break and cytomegaloviral retinitis [Figure 2b]. Ultrasound showed retinal detachment in the left eye.

Figure 2

(a) The right eye of Case 2, a patient with acquired immunodeficiency syndrome, has a small pupil with posterior synechia. (b) Ultrawide field fundus image shows areas of cytomegaloviral retinitis (square) with a large posterior retinal break (arrow) and retinal detachment.

DISCUSSION

Ultrawide field fundus imaging uses red (635 nm), and green (532 nm) lasers that provide a single panoramic image of 200° or 82% of the retina. Blue laser (488 nm) is used for ultrawide field fundus fluorescein angiography. The Optos machine incorporates an ellipsoid mirror with two focal points. The laser ray is passed through one of the focal points, and the position of the patient's eye is adjusted to keep the second focal point behind the pupil.[12] This enables peripheral retinal imaging in <1 s without the need for mydriasis.[3] UWFI has been shown to be useful for imaging uveitis patients and monitoring their progression or response to treatment.[4] In our clinical practice, Optos is proving to be an important tool for imaging the peripheral fundus in cases of uveitis with non-dilating pupils and/or early cataracts. Objective documentation and patient counseling may become easier with such imaging. However, cost, maintenance, and difficulty in imaging the superior and inferior retina continue to be the drawbacks of this promising imaging modality.