Browsing by Author "Yilmaz, Yusuf Cem"

Now showing 1 - 2 of 2

Corneal and Lens Densitometry in Patients With Vernal Keratoconjunctivitis
(Springer, 2021) Yilmaz, Yusuf Cem; Ipek, Sefik Can; Ozer, Muhammet Derda
Aim To evaluate corneal and crystalline lens densitometry in patients with vernal keratoconjunctivitis (VKC). Methods This is a case-control study. Patients with VKC and age-gender-matched healthy controls underwent a complete ophthalmologic examination with corneal and crystalline lens densitometry measurements. Additionally, the anterior chamber parameters comprise anterior and posterior K-mean and astigmatism, anterior chamber depth (ACD), anterior chamber volume (ACV), anterior chamber angle (ACA), pachymeter, and corneal volume (CV). Patients who had clinically grade 0 or grade 1 VKC and with only tarsal conjunctiva involvement during the conductance of the study were included. The variables were compared statistically. Results One hundred and nine eyes were included in the study, in which fifty-one were in the VKC group. There were 25 males in the VKC group (26 female) and 22 males in the control group (36 female). A statistically significant difference was found between the groups in terms of posterior corneal astigmatism (p = 0.02). The mean corneal pachymeter, CV, ACD, ACA, and ACV were similar in both groups (p = 0.63, p = 0.26, p = 0.60, p = 0.41, and p = 0.32, respectively). The total mean corneal densitometry in the zones extending from 6 to 10 mm and 10 to 12 mm was increased in the VKC group compared to the control group (p = 0.04 and p = 0.012, respectively). The mean crystalline lens was found to be denser in the VKC group compared to the control group (8.96 +/- 1.6 vs. 8.5 +/- 0.57, respectively, p = 0.04). Conclusion Posterior corneal astigmatism is increased in VKC cases in comparison with age- and gender-matched controls. The peripheral anterior 6-12 mm annular corneal zone showed increased corneal densitometry in VKC cases compared to the healthy subjects. Additionally, the lens clarity is found to be decreased subclinically in VKC cases compared to control cases.
The Surgical Outcomes of Limbal Allograft Transplantation in Eyes Having Limbal Stem Cell Deficiency
(Wolters Kluwer Medknow Publications, 2020) Ozer, Muhammet Derda; Altinkurt, Emre; Yilmaz, Yusuf Cem; Gedik, Ali Ceyhun; Alparslan, Nilufer
Purpose: To report the limbal allograft transplantation and penetrating keratoplasty (PK) results in limbal stem cell deficiency (LSCD)-developed eyes because of chemical or thermal injury. Methods: Medical records of 18 eyes of 14 patients who had undergone keratolimbal allograft (KLAL) or living-related conjunctival limbal allograft (lr-CLAL) with or without PK and followed up at least 1 year postoperatively were evaluated retrospectively. The preoperative LSCD grade was noted in all patients. Rejection incidents, recurrence of LSCD, and corneal graft clarity along with a visual improvement during the follow-up were noted. The complications rate due to surgery or injury itself, for instance, glaucoma and cataract, were evaluated. The limbal allograft tissue survival analysis and corneal allograft survival analysis were done to reveal the differences in both the procedures. The existence of normal corneal epithelium and improvement in visual acuity were accepted as the surgical success criteria. Results: In the limbal allograft transplantation group, the survival rates of the allograft tissue were 65 +/- 10.7% at 1 year and 36.6 +/- 11.4% at 3 years in lr-CLAL and 66.7 +/- 15.7% at 12 months and 53.3 +/- 17.3% at 18 months in KLAL-transplanted eyes. The survival rate of corneal allograft at the 5th postoperative year was lower in the simultaneous procedure compared to the staged procedure, but it was not statistically significant (25.7 +/- 25.8% vs. 62.5 +/- 17.1%, P = 0.75). The ambulatory vision was achieved in 10 eyes (56%) after a mean follow-up time of 93.8 +/- 37.8 months. The visual acuity level has increased in 12 eyes (67%) in which the limbal allograft transplantation was applied. The ambulatory visual acuity level was achieved (<= 1.0 logMar [20/200]) in 10 eyes (56%). In addition, two or more Snellen lines' gain in the best corrected visual acuity was observed in 12 eyes of 18 (67%) at the last follow-up, and there was not any significant difference between the KLAL and lr-CLAL. Conclusions: Ocular surface integrity was longer in KLAL than in lr-CLAL transplantation, but it was not statistically significant. The staged procedure was more convenient than the simultaneous procedure in terms of corneal allograft clarity maintenance in limbal allograft-employed eyes.