Pellucid marginal degeneration (PMD) is a rare corneal ectatic disorder that is common in men in the fourth to fifth decade, which presents with bilateral and often asymmetrical peripheral corneal thinning in a crescentic manner with high against-the-rule astigmatism.1 Unlike keratoconus, the incidence of acute hydrops is rare, and no clear-cut modality of treatment has been described for the same.2 Also, only very few cases of hydrops and acute spontaneous perforation have been described in the literature.
A 64-year-old man presented to the clinic with blurring of vision in the right eye and was found to have an uncorrected distance visual acuity of 3/60 and a corrected distance visual acuity (CDVA) of 6/18 with a −12.00 diopter (D) cylinder axis at 65 degrees. On examination, a crescentric arcuate irregular reflex 2.0 mm away from the limbus extending from the 4 o'clock to 8 o'clock position was noted. Fellow eye uncorrected distance visual acuity was 6/6 and normal on clinical examination. On topography (Pentacam, OCULUS Optikgeräte GmbH), the right eye showed the crab claw sign with against-the-rule astigmatism of −12.00 D at 65 degrees, and K1 (flat keratometry) and K2 (steep keratometry) were 37.90 D at 60 degrees and 51.10 D at 165 degrees, respectively. The fellow eye was completely normal with normal topography and pachymetry. Figures 1 and 2 show the topographic images of the right and left eye, with right eye CDVA improving to 6/6 and left eye at presentation. A diagnosis of PMD was made, and a scleral contact lens was prescribed (the patient did not use it and preferred spectacles).
Four months later, the patient presented with a sudden decrease in vision with acute pain in the right eye and was noted to have full-thickness perforation at the 6 o'clock to 7 o'clock position measuring approximately 2.5 mm with iris prolapse as shown in Figure 3. The defect was surgically repaired with suturing (2 sutures as primary sutures at the perforation site) and iris repositioning with additional compression sutures along the crescentric area (2 sutures on either side of the primary sutures directed along the flat axis obtained from the topographic images) as shown in Figure 4. Six interrupted radial sutures were placed using 10-0 nylon (Ethilon) and a bandage contact lens was placed. On postoperative day 1, the anterior chamber was formed, and sutures were intact and topical medications (moxifloxacin eye drops 0.5%, hydroxypropyl methylcellulose 0.3%, and homatropine 2%) were given. Topical steroids (loteprednol 0.5%) were started on the second postoperative day and slowly tapered over 6 weeks. At the fourth-month postoperative period, alternate suture removal was performed and removed subsequently over a period of 1 month. After suture removal, the patient obtained a CDVA of 6/9 (−2.75 D cylinder at 90 degrees), and topographically, there was a reduction in steep K (K2 = 42.8 D at 160 degrees) and regularization of the cornea as shown in Figures 5 and 6 at 6 months postoperatively. The patient has follow-up. The left eye shows no clinical or topographical evidence of PMD 2 years after the procedure.
Spontaneous perforation and only unilateral involvement is rare in PMD. In the literature, very few cases are reported and each with a variable presentation and management.1 This case is unique in not only its presentation but also its management where the perforation site was managed with primary suturing and additional compression sutures. The sutures helped steepening the flat axis with almost 6.00 D reduction in K2. This also helped in regularizing the central cornea with an improvement in CDVA. Some studies have shown conservative management of smaller perforations with fibrin glue and larger perforations with a banana corneal graft, full-thickness penetrating keratoplasty, and even tuck-in lamellar keratoplasty.2–5 To our knowledge, this is the first case report in which compression sutures were used both for acute management and regularization of the cornea. This method might eliminate the risk for future rejections associated with corneal transplants and grafts. Thus, compression sutures can be used as an effective method of treatment in patients with PMD who present with a slightly larger perforation where conservative management like glue are not useful; it can also be used for regularization of the cornea in patients with PMD. However, a longer follow-up and larger series may be needed to prove the same.
1. Jinabhai A, Radhakrishnan H, O’Donnell C. Pellucid corneal marginal degeneration: a review. Cont Lens Anterior Eye 2011;34:56–63
2. Symes RJ, Catt CJ, Sa-ngiampornpanit T, Males JJ. Corneal perforation associated with pellucid marginal degeneration and treatment with crescentic lamellar keratoplasty: two case reports. Cornea 2007;26:625–628
3. Forooghian F, Assaad D, Dixon WS. Successful conservative management of hydrops with perforation in pellucid marginal degeneration. Can J Ophthalmol 2006;41:74–77
4. Gharebaghi D, Fallahi B, Javadzadeh A, Amiraslanzadeh G. Spontaneous corneal hydrops and perforation in pellucid marginal degeneration; a case report. J Ophthalmic Vis Res 2009;4:174–176
5. Lee WB, O'Halloran HS, Grossniklaus HE. Pellucid marginal degeneration and bilateral corneal perforation: case report and review of the literature. Eye Contact Lens 2008;34:229–233