Spontaneous Amsler’s sign

We report an interesting case of a 39-year-old male patient with anterior uveitis who had recently been diagnosed with Fuchs' heterochromic cyclitis (FHC) in our outpatient department (OPD) 2 months back. He subsequently presented to the OPD in an emergency, having noticed severe blurring of vision in his right eye on waking up. His best-corrected visual acuity was 6/6, N6 in both eyes. A slit-lamp examination of the right eye revealed a mild anterior chamber reaction, with a few keratic precipitates on the endothelium. The intraocular pressure was 28 mmHg in the right eye and 13 mmHg in the left eye. Such blurring is usually related to high intraocular pressure in these cases of hypertensive iridocyclitis. However, in our case, there was a streak of hyphema at 9 o'clock, suggestive of spontaneous Amsler's sign [Figure 1]. We also demonstrate the use of infrared photography of the anterior segment to highlight the subtle iris changes in FHC seen in our case, which is classically called the moth-eaten appearance of the iris [Figure 2].Figure 1: Spontaneous hemorrhage (arrow) at 9 o'clock position in the right eye in Fuchs' heterochromic cyclitis (Amsler's sign)Figure 2: Iris near-infrared autofluorescence: Note the altered pattern with petaloid moderate autofluorescence pattern in the pupillary zone, minimal autofluorescence in the deep radial troughs, and reticular pattern in the ciliary zone in the right eye (a), and normal pattern in the left eye (b)Amsler's sign is classically described as a streak of hyphema occurring diametrically opposite to the site of paracentesis in cases of FHC classically noted during initial anterior chamber entry during cataract surgery.[1] A case of spontaneous hyphema in FHC, very similar to our case, has earlier been reported.[2] Six cases of spontaneous Amsler's sign in patients with Fuchs' uveitis syndrome without any intervention have also been reported earlier.[3] We report yet another unique case of spontaneous Amsler's sign in FHC with high intraocular pressure. Iris near-infrared autofluorescence (NIR-AF) is a noninvasive imaging technique that uses near-infrared light to detect autofluorescent molecules in the iris. In FHC, iris NIR-AF imaging has shown a decrease in the iris autofluorescence signal in the affected eye compared to the unaffected eye. This decrease is thought to be due to the loss of iris pigmentation, which is a hallmark feature of FHC. In addition, the distribution of iris NIR-AF is altered in FHC, with increased heterogeneity and decreased regularity. One of the advantages of iris NIR-AF imaging is that it allows for the detection of subtle changes in iris pigmentation that may not be visible on clinical examination. In addition, this technique is noninvasive, is rapid, and can be easily performed in an outpatient setting. Overall, iris NIR-AF imaging is a promising tool for studying the changes in iris pigmentation and autofluorescence in FHC. The rise in intraocular pressure in FHC is believed to be due to trabeculitis. A rarer cause is subtle angle neovascularization leading to decreased aqueous outflow. However, in our case, angle neovascularization was not present on gonioscopy [Figure 3]. Out of the six cases of spontaneous Amsler's sign reported earlier, two of them were seen only through gonioscopy.[3] Another case of rubeosis of the anterior chamber angle in FHC has also been reported.[4]Figure 3: No neovascularization of angle was noted at 9 o'clock position in the right eye as evidenced by visualizing the angle at 3 o'clock position through indirect gonioscopyOur case highlights a very unusual presentation of FHC. It also elegantly demonstrates the use of near-infrared photography of the anterior segment for documentation of subtle iris pathologies in FHC. This imaging is a promising objective and noninvasive technique to document the iris changes and/or help distinguish FHC from other uveitis entities that might require more aggressive treatment. It may help clarify a confounding clinical picture and reduce the often years-long delay in diagnosis of FHC. This emphasizes the use of an emerging technique of anterior segment multimodal imaging in uveitis documentation.[5] However, further studies are needed to determine its clinical utility and its correlation with other clinical features of FHC. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.