- Home
- Medical news & Guidelines
- Anesthesiology
- Cardiology and CTVS
- Critical Care
- Dentistry
- Dermatology
- Diabetes and Endocrinology
- ENT
- Gastroenterology
- Medicine
- Nephrology
- Neurology
- Obstretics-Gynaecology
- Oncology
- Ophthalmology
- Orthopaedics
- Pediatrics-Neonatology
- Psychiatry
- Pulmonology
- Radiology
- Surgery
- Urology
- Laboratory Medicine
- Diet
- Nursing
- Paramedical
- Physiotherapy
- Health news
- Fact Check
- Bone Health Fact Check
- Brain Health Fact Check
- Cancer Related Fact Check
- Child Care Fact Check
- Dental and oral health fact check
- Diabetes and metabolic health fact check
- Diet and Nutrition Fact Check
- Eye and ENT Care Fact Check
- Fitness fact check
- Gut health fact check
- Heart health fact check
- Kidney health fact check
- Medical education fact check
- Men's health fact check
- Respiratory fact check
- Skin and hair care fact check
- Vaccine and Immunization fact check
- Women's health fact check
- AYUSH
- State News
- Andaman and Nicobar Islands
- Andhra Pradesh
- Arunachal Pradesh
- Assam
- Bihar
- Chandigarh
- Chattisgarh
- Dadra and Nagar Haveli
- Daman and Diu
- Delhi
- Goa
- Gujarat
- Haryana
- Himachal Pradesh
- Jammu & Kashmir
- Jharkhand
- Karnataka
- Kerala
- Ladakh
- Lakshadweep
- Madhya Pradesh
- Maharashtra
- Manipur
- Meghalaya
- Mizoram
- Nagaland
- Odisha
- Puducherry
- Punjab
- Rajasthan
- Sikkim
- Tamil Nadu
- Telangana
- Tripura
- Uttar Pradesh
- Uttrakhand
- West Bengal
- Medical Education
- Industry
YAG laser peripheral iridotomy not tied to significant corneal endothelial damage: RCT
Primary angle closure glaucoma (PACG) accounts for nearly a half of global blindness caused by glaucoma. Laser peripheral iridotomy (LPI) is the conventional first-line treatment for individuals with primary angle closure. While LPI is generally felt to be safe, there have been reports of corneal complications including oedema and decompensation after argon laser iridotomies.
The short-term safety of Nd:YAG LPI has been established, but long-term evaluation is limited. The cell count and corneal cell morphology is relevant to corneal endothelial function and decompensation. Limited studies have reported the effect of Nd:YAG laser on endothelial hexagonality.
Liao C, et al performed an analysis to evaluate the influence of Nd:YAG LPI on corneal endothelial cell density (ECD) and morphology in PACS patients over 72 months which was published in British Open Ophthalmology Journal.
"Over 72 months of observation after YAG LPI, corneal ECD declined and morphology changed in both treated and fellow eyes of PACS patients. Although the difference in ECD between treated and fellow eyes was not statistically significant before 54 months, it became statistically significant at 72 months after LPI. That said, the difference was small (<1%).
The study found no association between ECD loss and laser energy required to complete the LPI, suggesting the energy used to create the LPI was not the primary cause of the longterm effect and was minimally invasive to endothelial cells. It is possible that endothelial cell damage could result from environmental changes at the level of the endothelium after iridotomy owing to alterations in aqueous dynamics, breakdown of the blood-aqueous barrier and suspended debris in the aqueous humour."
Ageing is another important factor accounting for the ECD decline in eyes with or without YAG LPI. One explanation can be eyes with shallower anterior chambers are more predisposed to endothelial cell loss due to the increased possibility of irido-trabecular contact. The ECD changes over time among the untreated eyes is primarily driven by ageing effects instead of narrow angles.
The randomised controlled trial design, large sample size, high follow-up rate, long duration of observation and mixed model analysis allowing for inclusion of a time effect are the major advantages of this study.
The study concluded, "a significant decline in ECD was observed in both YAG LPI-treated eyes and control eyes, which was primarily attributed to the ageing effect. The difference between them was not statistically significant until 72 months after the procedure, with a smaller difference of 0.74% (95% CI −1.23% to −0.24%) and minimum clinical significance.Mean cell areas increased significantly over time in both treated and fellow eyes (p<0.01), , but no longitudinal change was observed for hexagonality. In LPI-treated eyes, no significant correlation was found between age, gender, ocular biometrics, intraocular pressure and laser settings with endothelium change, except for time effect (p<0.01)."
Further investigation of the peripheral cornea would help to understand better the long-term safety of YAG LPI.
Source: : Liao C, Zhang J, Jiang Y, et al. Br J Ophthalmol 2021;105:348–353.
Dr Ishan Kataria has done his MBBS from Medical College Bijapur and MS in Ophthalmology from Dr Vasant Rao Pawar Medical College, Nasik. Post completing MD, he pursuid Anterior Segment Fellowship from Sankara Eye Hospital and worked as a competent phaco and anterior segment consultant surgeon in a trust hospital in Bathinda for 2 years.He is currently pursuing Fellowship in Vitreo-Retina at Dr Sohan Singh Eye hospital Amritsar and is actively involved in various research activities under the guidance of the faculty.
Dr Kamal Kant Kohli-MBBS, DTCD- a chest specialist with more than 30 years of practice and a flair for writing clinical articles, Dr Kamal Kant Kohli joined Medical Dialogues as a Chief Editor of Medical News. Besides writing articles, as an editor, he proofreads and verifies all the medical content published on Medical Dialogues including those coming from journals, studies,medical conferences,guidelines etc. Email: drkohli@medicaldialogues.in. Contact no. 011-43720751