Application of hyperbaric oxygen therapy as a primary treatment in cases of clinically significant macular edema in diabetic patients

Abstract

Hyperbaric Oxygen therapy is a way of treatment that high concentrated oxygen at higher pressure than normal atmospheric pressure is used to increase PaO2 that has a beneficial biochemical, cellular, and physiological effects, which can be used generally in ischemic diseases to increase oxygen supply to ischemic tissue, and in inflammatory diseases as the high oxygen perfusion can increase the healing process. Diabetic retinopathy is an ischemic inflammatory condition of the retina that occurs with chronic patients of diabetes mellitus. Diabetic retinopathy could be associated with DME, whether it was NPDR or PDR. CSME was defined as retinal thickening at or within 500 µm from the center of the macula, hard exudates at or within 500 µm from the center of the macula or if associated with thickening of the adjacent retina or a zone of retinal thickening larger than one disc area located within one disc diameter from the center of the macula identified on clinical examination. Many treatment modalities for DME are used nowadays, this includes focal or grid argon laser photocoagulation, pars plana vitrectomy with and without ILM peeling, intravitreal injections using triamcinolone acetonide or anti-VEGF inhibitors, and HBOT. In ophthalmology, HBO is used in various ischemic diseases such as occlusive vasculopathies, macular edema due to blood-retinal barrier breakdown in patients with diabetic retinopathy, CME of vascular origin, scleral necrosis of avascular origin, orbital infections of mycotic and anaerobic origin, nonhealing corneal edema, anterior segment ischemia, proliferative vitreoretinopathy due to sickle cell disease, primary open-angle glaucoma, visual field defect after macular hole surgery, macular detachment and optic neuropathies of vascular origin, as a main or adjuvant therapeutic way of treatment. In our research 10 eyes were selected with CSME in order to receive HBOT in Egyptian Aerospace Medical Institute, receiving 40 sessions, 5 sessions per week, each session took 90 minutes, then follow up was done for a period of one month, results were collected and analyzed statistically to conclude how effective is the treatment of DME using HBO. After the analysis of the collected data, HBOT were proven to be effective in improving the BCVA in 70% of the eyes receiving the treatment and the CMT in almost all of the eyes receiving the treatment, this would prove that using HBO is reliable and effective as a main therapeutic method in cases of diabetic retinopathy associated with CSME. Comparing the results of our research to the older researches done on HBOT in ocular diseases, it was found that the results were nearly the same in comparison to older researches that were done on subjects with CSME of vascular origin, which stress on how effective was HBO on the treatment of CSME associated with diabetic retinopathy.