Distribution of corneal densitometry in different grades of keratoconus.

Purpose: To evaluate the use of Scheimpflug tomography in corneal densitometry (CD) in comparing the stages of keratoconic eyes. Methods: Keratoconic (KC) corneas (stages 1-3 classified according to the topographic parameters) were examined using the Scheimpflug tomographer (Pentacam, Oculus) using the CD software. CD was measured over three different depths (anterior stromal layer [120 µm], posterior stromal layer [60 µm], and middle stromal layer between these two layers), and concentric annular zones (0.0 to 2.0, 2.0 to 6.0, 6.0 to 10.0, and 10.0 to 12.0 mm diameter area). Results: The study participants were divided into three groups: keratoconus (KC) stage 1 (KC1) with 64 participants, keratoconus stage 2 (KC2) with 29 participants, and keratoconus stage 3 (KC3) with 36 participants. Comparing CD of all three layers (anterior, central, and posterior) of the cornea over different circular annuli (0-2, 2-6, 6-10, and 10-12 mm) revealed a significant difference in the 6-10 mm annulus between all groups and in all layers (P = 0.3, 0.2, and 0.2, respectively). Area under curve (AUC) was done. It revealed that the central layer showed the highest specificity (93.8%) in comparing KC1 and KC2, whereas CD in the anterior layer between KC2 and KC3 had the highest specificity (86.2%). Conclusion: CD showed increased values in the anterior corneal layer and in the annulus 6-10 mm more than other locations in all stages of KC.

Closed-Chamber Anterior Capsulorhexis Under Air Tamponade In White Cataract.

PURPOSE: To evaluate the efficacy and safety of a closed-chamber air bubble capsulotomy technique to prevent the Argentinean flag sign (AFS) in patients with white and intumescent cataracts. SETTING: Sohag University, Faculty of Medicine, Ophthalmology Department, Sohag, Egypt. DESIGN: Prospective interventional noncomparative case series. METHODS: Eighty-two eyes of 80 patients with white and intumescent cataracts were included. Eyes with any ocular pathology other than cataract or eyes subjected to previous intraocular surgery were excluded. Needle capsulorhexis was performed under a large air bubble tamponade without capsular staining. Efficacy of the technique was assessed intraoperatively by successful completion of capsulorhexis. Safety of the technique was assessed by the occurrence of intraoperative or postoperative complications. RESULTS: Complete capsulorhexis by the closed-chamber air bubble technique was successful in 75 eyes (91.5%), while capsulorhexis extension occurred in seven eyes. In four eyes with extension, the procedure was shifted to the standard technique of CCC (circular curvilinear capsulorhexis), using a viscoelastic device. A shift to extracapsular cataract extraction (ECCE) surgery occurred in the remaining three eyes, as the extension was so far-gone. No intraoperative or postoperative complications were observed. CONCLUSION: The closed anterior chamber air bubble technique for capsulorhexis is a novel, safe, and effective technique to prevent AFS in white and intumescent cataracts. It is also time-saving and cost-effective, with less likelihood of capsulorhexis extension. The technique is considered a valuable addition to previously described techniques.