{'fraction_non_alphanumeric': 0.03860407659048796, 'fraction_numerical': 0.020691785052501546, 'mean_word_length': 5.313840155945419, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Increased Reaction after Cross-linking in Keratoconus Melanoderm Patients

Corneal collagen cross-linking (CXL) using riboflavin and ultraviolet-A is an etiopathogenetic and innovative therapy for keratoconus. Histological changes after CXL have been well described on confocal microscopic images. Early postoperative findings include keratocyte apoptosis and anterior stromal edema. At the third month postoperatively, the stromal edema disappears and is followed by keratocyte population recovery and increase in stromal fiber density. On optical coherence tomography (OCT) images, only the corneal stromal demarcation line that corresponds to the transition zone between the cross-linked anterior corneal stroma and the untreated posterior corneal stroma has been recently described, indicating the transition zone between cross-linked anterior corneal stroma and untreated posterior corneal stroma. This line is clearly visible 1 month after corneal cross-linking, indicating probably the efficiency of the procedure. Melanoderm patients are considered at high risk for excessive scaring reaction after surgery. To the best of our knowledge, stromal reaction after CXL in this group of patients has not been evaluated. In this brief report, we describe aspects of increased stromal reaction observed in 4 eyes of 3 melanoderm patients who underwent CXL for evolutive keratoconus. These patients underwent cross-linking between January 2010 and May 2011 at the Quinze-Vingts National Ophthalmology Hospital (Paris, France). During the same period, 116 patients were scheduled to have CXL. Fourteen patients among them were melanoderm. Patients with pigmented skin and iris coloration were considered melanoderm patients regardless of their ethnicity. Progression of keratoconus was defined as an increase in the maximum K-value by more than 1.0–1.5 diopters (D) and a corresponding change (1.0–1.5 D) in the refractive cylinder in the previous 6–12 months. Patients received standard UVA–riboflavin 0.1% CXL treatment. After a 9-mm-diameter corneal epithelium abrasion, photosensitizing riboflavine (0.1% in 20% dextran T500 solution) solution was applied on the cornea every 3 min for 30 min. The central cornea was irradiated using UVA 365-nm light (8.0-mm diameter, 3.0-mW/cm irradiance) for 30 min (UV-X system, IROC AG, Zurich, Switzerland). Riboflavin eyedrops were applied every 5 min during the UVA exposure. After the riboflavin–UVA treatment, a therapeutic soft contact lens was applied for 3 days. Topical dexamethasone and tobramycin were given 4 times daily and gradually tapered over 1 month. Postoperatively patients were examined 1 week and 1, 3, and 6 months after the CXL treatment. The patient workup included the best spectacle-corrected visual acuity (BSCVA), slit-lamp examination, corneal topography (Orbscan IIz, B&L, Rochester, NY, USA), anterior spectral-domain OCT (AS-OCT) (RTVue, Optovue, Fremont, CA), specular microscopy (Noncon Robo SP-9000, Konan Medical, Hyogo, Japan), and in vivo laser scanning confocal microscopy (Heidelberg Retinal Tomograph II with Rostock Cornea Module, Heidelberg, Germany). The mean age of patients was 26 years (ranging from 24 to 27 years). There were 2 females and 1 male.