|Year : 2022 | Volume
| Issue : 1 | Page : 271-272
Direct slit-lamp view of angle of anterior chamber in superior corneal ectasia
Arjun Velayudhan Nair, Mangala Periasamy, Revathi Rajaraman
Department of Cornea and Refractive Services, Aravind Eye Hospital and Post-Graduate Institute of Ophthalmology, Coimbatore, Tamil Nadu, India
|Date of Submission||26-May-2021|
|Date of Acceptance||23-Aug-2021|
|Date of Web Publication||07-Jan-2022|
Dr. Arjun Velayudhan Nair
Department of Cornea and Refractive Services, Aravind Eye Hospital and Post-Graduate Institute of Ophthalmology, Coimbatore - 641 014, Tamil Nadu
Source of Support: None, Conflict of Interest: None
Keywords: Angle of anterior chamber, gonioscopy, superior pellucid marginal degeneration
|How to cite this article:|
Nair AV, Periasamy M, Rajaraman R. Direct slit-lamp view of angle of anterior chamber in superior corneal ectasia. Indian J Ophthalmol Case Rep 2022;2:271-2
|How to cite this URL:|
Nair AV, Periasamy M, Rajaraman R. Direct slit-lamp view of angle of anterior chamber in superior corneal ectasia. Indian J Ophthalmol Case Rep [serial online] 2022 [cited 2022 Jan 23];2:271-2. Available from: https://www.ijoreports.in/text.asp?2022/2/1/271/334871
A 48-year-old female presented with complaints of defective vision in both eyes. Her uncorrected visual acuity was 6/60 in the right eye (RE) and 5/60 in the left eye (LE), best-corrected visual acuity was 6/9 in the RE and 6/36 in the LE. LE had a superior crescent-shaped area of thinning extending from 10 to 2 o'clock [Figure 1]a and [Figure 1]b. On slit-lamp examination, angle structures were visualized without the use of gonioscope [Figure 1]c, [Figure 1]d, and [Figure 2]. Steep cornea and the interface created by cornea and tear drop changed the critical angle circumventing total internal reflection. LE Pentacam (Oculus; Wetzlar, Germany) showed superior elevation in both elevation maps, superior loop cylinder with extension onto horizontal meridian in keratometry map [Figure 3]a and an inverted bell [Figure 3]b in pachymetry. RE had steep cornea clinically and topographically. The patient was diagnosed with superior pellucid marginal degeneration (SPMD) in LE.
|Figure 1: Slit-lamp photograph corneal ectasia with superior steepening and thinning (a). Tear film and corneal interface through which angle structures become visible (b). Tilted slit beam with broad overview of inferior angle structures and V-shaped lower lid indentation (c). Magnified view of angle structure with pigmented trabecular meshwork (d)|
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|Figure 2: Slit-lamp photograph in higher magnification showing open-angle, pigmented schwalbe's line (shown by black arrow) up to ciliary body band and root of iris (shown by white arrow); lid margin indentation also seen (Munson's Sign) below the tear film (a)|
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|Figure 3: Topography keratometry map with superior loop cylinder (a). Pachymetry map showing inverted bell shape (b)|
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| Discussion|| |
Generally, the light coming from the anterior chamber angle is totally internally reflected, making the viewing of the angle impossible. The gonioscope changes the interface from cornea–air to lens–air, changing the critical angle and thus permitting viewing of the angle structures. The first person to observe the angle in vivo was the Greek ophthalmologist, Alexios Trantas, in an eye with keratoglobus. He devised a method using direct ophthalmoscopy combined with digital pressure on the limbus; with this method, he examined the ciliary body up to the anterior retina. Trantas publication in Gazette Midicale d'orient in 1901, he described in “Keratoglobe Congenitale,” the angle of the anterior chamber can be seen with and without digital pressure with the direct ophthalmoscope and the help of a + 4 to + 15 lens. This photo essay highlights the confluence of two uncommon findings: isolated SPMD and direct-angle visualization without gonioscopy.
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 initial s will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Sridhar MS, Mahesh S, Bansal AK, Rao GN. Superior pellucid marginal corneal degeneration. Eye 2004;18:393-9.
Thomas R, Thomas S, Chandrashekar G. Gonioscopy. Indian J Ophthalmol 1998;46:255-61.
] [Full text]
Dellaporta A. Historical notes on gonioscopy. Survey Ophthalmol 1975;20:137-49.
[Figure 1], [Figure 2], [Figure 3]