Publications by authors named "Kianoush Shahraki"

6 Publications

  • Page 1 of 1

Corneal biomechanical outcome of collagen cross-linking in keratoconic patients evaluated by Corvis ST.

Eur J Ophthalmol 2020 Jul 25:1120672120944798. Epub 2020 Jul 25.

Department of Optometry, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.

Purpose: A 6-month evaluation of the topographic and biomechanical changes induced by corneal collagen cross-linking (CXL) in keratoconic eyes using Pentacam and Corvis ST.

Design: Longitudinal prospective case series.

Methods: In this study, 67 eyes of 67 patients with progressive keratoconus (KCN) treated with "Epithelium-off" CXL were evaluated. Patients with stages 1 or 2 of KCN and a corneal thickness of at least 400 μm at the thinnest point were included. Standard ophthalmologic examinations were carried out for all patients. The topographic and biomechanical measurements of the cornea were obtained by Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) and Corvis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany) preoperatively and 6-month postoperatively.

Results: The mean age of the participants was 21.68 ± 4.23 years. There was significant difference in mean spherical equivalent (SE) before and 6 months after CXL. Uncorrected and best corrected visual acuity improved postoperatively, although not statistically significant. The mean and maximum keratometry showed a significant decrease 6 months after CXL (0.93 ± 0.38 D and 1.43 ± 0.62 D, respectively  < 0.001). Among Corvis ST parameters, first applanation length and velocity (AL1 and AV1) showed statistically significant changes. The radius at highest concavity changed significantly (0.13 ± 0.37 mm mean increase after CXL;  < 0.001). A significant increase was observed in stiffness parameter A1 (SP-A1;  < 0.001) and significant decreases were noted in integrated radius (IR) and deformation amplitude ratio (DAR;  < 0.001).

Conclusion: Analyzing biomechanical changes after corneal cross-linking can provide basis for efficient KCN treatment. Corvis ST parameters demonstrated changes in corneal biomechanical characteristics indicative of stiffing after CXL.
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July 2020

Sutureless Femtosecond Laser-Assisted Anterior Lamellar Keratoplasty Using a Bioengineered Cornea as a Viable Alternative to Human Donor Transplantation for Superficial Corneal Opacities.

Cornea 2020 Sep;39(9):1184-1189

Eye Research Center, Eye Department, Amiralmomenin Hospital, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran.

Purpose: To evaluate the safety and efficacy of a bioengineered corneal implant using femtosecond laser-assisted anterior lamellar keratoplasty for superficial corneal opacities.

Methods: Six eyes of 6 consecutive patients with superficial corneal stromal opacities involving <220 μm owing to various pathologies were included in the study. Preoperatively, all patients underwent anterior segment optical coherence tomography (Visante; Carl Zeiss Meditec AG) to evaluate the depth of the corneal opacity. All patients underwent sutureless femtosecond laser-assisted anterior lamellar keratoplasty using a bioengineered collagen corneal implant (linkcor). Visual indices, refraction, and keratometry were evaluated preoperatively and 12 months postoperatively.

Results: Corrected distance visual acuity improved significantly in all patients (P = 0.02). A significant decrease was seen in refractive astigmatism postoperatively (P = 0.04). Flat keratometry reduced significantly 12 months after the intervention (P = 0.04). No intraoperative or early postoperative complications were noticed. All implants were fully covered by healthy epithelium within a month after the surgery and remained clear at follow-up visits. The results of this procedure remained stable throughout the follow-up period. In 1 patient, mild inferior collagen melting and epithelial defect formation occurred at 1-year follow-up. Despite frequent topical corticosteroid therapy the melting progressed, the collagen tissue was removed and the patient was treated accordingly with good visual outcomes.

Conclusions: Femtosecond laser-assisted anterior lamellar keratoplasty with bioengineered corneal (linkcor) implantation is an effective treatment for improving vision quality in anterior stromal opacities. This procedure reduces the need for human donor tissue and avoids human donor-related and suturing complications.
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September 2020

COVID-19 pandemic: Ophthalmic practice and precautions in a tertiary eye hospital in Iran.

Infect Control Hosp Epidemiol 2020 Oct 23;41(10):1237-1238. Epub 2020 Apr 23.

Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Iran.

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October 2020

Effects of intracameral cefuroxime on corneal endothelial cell counts and its morphology after cataract surgery.

Interv Med Appl Sci 2017 Jun;9(2):100-104

Department of Ophthalmology, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.

Background: Endophthalmitis is one of the most important complications after cataract surgery and in case event can cause many symptoms, such as severe decrease in eyesight and/or even the loss of vision. Employing methods to reduce this problem is very important. The aim of this study was to evaluate the effect of intracameral cefuroxime after cataract surgery on corneal endothelial cell counts and its morphology.

Methods: In this study, 32 eyes of 30 patients underwent endothelial cell count and morphology assessment by ConfoScan III device before and 1 month after cataract surgery. All patients undertaken cataract surgery by one surgeon and by one method. Intracameral cefuroxime (1 mg/0.1 ml) was used as prophylaxis of postoperative endophthalmitis at the end of operation.

Results: In this study, the rate of corneal endothelial cell loss 1 month after cataract surgery was 8.4%, and the rate of endothelial cells polymegathism before and after cataract surgery did not differ statistically. During the follow-up period, there were no cases of endophthalmitis or other complications.

Conclusion: With regard to the importance of the intracameral cefuroxime in a reduction in the rate of endophthalmitis after cataract surgery and that harmful effects on the endothelial cells were not seen, this method can be considered as a suitable method for endophthalmitis prophylaxis.
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June 2017

Effects of Topical 1% Sodium Hyaluronate and Hydroxypropyl Methylcellulose in Treatment of Corneal Epithelial Defects.

Med Hypothesis Discov Innov Ophthalmol 2016 ;5(4):136-144

Department of Ophthalmology, Alzahra Eye Hospital, Zahedan University of Medical Sciences, Zahedan, Iran.

We aimed to compare the therapeutic effects of topical 1% sodium hyaluronate (Healon) or hydroxypropyl methylcellulose (HPMC) for the treatment of alkali-induced epithelial corneal defects. An alkali burn was produced in 30 corneas of 30 New Zealand White rabbits, using a 7.5-mm-diameter trephine. The rabbits were randomly divided into three groups. Four times a day, one group was treated with 1% sodium hyaluronate, one with HPMC, and one (the control group) with physiologic saline. During the treatment period, the size of the epithelial defect was observed every day, up to day 17, using a slit-lamp biomicroscope (with fluorescein). Sodium hyaluronate significantly accelerated the wound healing process compared with saline and increased the healing rate to an even greater extent compared with HPMC. Sodium hyaluronate, but not HPMC, is an effective wound-healing adjuvant for alkali-induced corneal epithelial defects.
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January 2016

Surgical treatments in inferior oblique muscle overaction.

J Ophthalmic Vis Res 2014 Jul-Sep;9(3):291-5

Brain and Spinal Injury Repair Research Center, Tehran University of Medical Sciences, Tehran, Iran ; Department of Ophthalmology, Eye Hospital, Hannover Medical School, Hannover, Germany.

Purpose: To compare the outcomes of surgical procedures in the treatment of inferior oblique muscle overaction (IOOA) as a common disorder of ocular motility.

Methods: This retrospective study was performed on patients with primary and secondary IOOA who underwent three surgical treatment procedures including disinsertion, myectomy and anterior transposition, between 2001 and 2011. Type of strabismus, ocular alignment, presence of pre-and post-operative dissociated vertical deviation (DVD), pre- and post-operative degree of IOOA were obtained using specified checklist.

Results: A total of 122 eyes of 74 patients with mean age of 13 ± 11.7 (range, 1-51) years were included in this study. Disinsertion was performed on 12 eyes (9.8%), myectomy in 91 eyes (74.6%) and anterior transposition in 19 (15.6%). Preoperative V-pattern and DVD existed in 67 and 17 eyes; after surgery they remained in only 10 and 8 eyes, respectively. The success rate (IOOA <+1), in disinsertion, myectomy and anterior transposition groups were 91.7%, 97.8%, and 89.5%, respectively and these measures did not change after 6 months. Overall, 53.3% (n = 65) and 38.5% (n = 47) of eyes had preoperative esotropia and exotropia. Preoperative hypertropia and hypotropia were observed in 16.4% (n = 20) and 3.3% (n = 4) of eyes, respectively. After surgery there were no cases of additional strabismus. However, residual hypertropia was seen in 9 eyes, while preoperative hypotropia increased in one patient who underwent anterior transposition surgery. Esotropia and exotropia were not observed in any surgical treatment groups postoperatively.

Conclusion: We conclude that all these three procedures are effective for treatment of primary or secondary IOOA with minimum side-effects.
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February 2015