Using hyperbaric oxygen in ophthalmology
Hyperbaric oxygen therapy has been recognized as an effective treatment method for various eye complications associated with diabetes, infections, intoxications, injuries, degenerative deseases or radiation therapy.
- Maintaining blood glucose level under control may prevent damage to the small blood vessel supplying the eyes.
- Regularly check your blood pressure and try to keep it within the normal values.
- Avoid activities that can raise the blood pressure. Also, birth control pills can increase the blood pressure
- If eye problems develop then early intervention such as laser treatment for retinopathy can decrease the risk of blindness by 90%
Yearly visit to ophthalmologist can confirm some of the following early signs of diabetes:
- Trouble reading books or traffic signs
- Problems distinguishing familiar objects
- Other visual problem such as spots, “floaters” or cobwebs in your field of vision, blurring or distortion, detection of blind spots, eye pain or persistent redness
- Increased pressure inside the eye may be the warning sign of glaucoma
- Sudden blindness or partial blindness (one eye) can be caused by the rupture of the vessels supplying the retina
- HBO improves visual sharpness (acuity) and reduces the incidence of blindness caused by lack of oxygen.
- HBO improves retinal blood flow and circulation. It its also effective in reducing swelling and thereby the risk of developing glaucoma and cataract.
- HBO reduces scar formation after surgery
- HBO speeds up the healing after surgery and reduces the complications
- HBO suppresses infection either directly by destroying bacteria or assisting white blood cells in phagocytosis.
- HBO improves the immune system response.
- HBO enhances the effect of some antibiotics.
Macular degeneration is a damage of the retina causing in severe cases the loss of vision in the central visual field. It is usually occurring in older population and is called age-related macular degeneration (AMD) and is a significant cause of visual loss in North America. As the population ages, the prevalence rate of advanced age-related macular degeneration is expected to double by 2030.
“A one-hour session of hyperbaric oxygen therapy was used to treat a group of 14 patients with advanced AMD. Eight patients were treated at 1.75 ATA, and six patients were treated at 1.5 ATA for one hour. Significant improvements in visual acuity and/or visual field, with improvements in the activities of daily living were observed.”
Retinal vein occlusion, diabetic macular edema and cystoid macular edema
Macular edema is defined as swelling of the retina due to protein and fluid deposits under the macula of the eye. It could be the result of cataract removal surgery, ischemic retinal vein occlusion and is common complication in people with diabetes. Hyperbaric oxygen therapy reduces swelling in the eye, decreases intraocular pressure, has anti-inflammatory effect, restores normal oxygen levels and micro-circulation, restores vision and improves visual acuity and has stable long term results. (Please see references below) Three week treatment schedule by Pfoff and Thom (1987) on five patients with cystoid macular edema showed improvement in vision in all patients within first two weeks. More related references are listed below but in some individuals, mostly with chronic condition such as diabetes the vision tends to regress with time.
Increased intra-ocular pressure
Reduced intra-ocular pressure by hyperbaric oxygen was reported in largest study by Ensali in 2006. In his compression to 2.5 ATA on 56 patients who have all improved with therapy. This was consistent with previous and later results listed below.
Effect of Hyperbaric oxygen therapy disorders of the eye:
- oxygenation and neo-vascularization
- instant increase of oxygen partial pressure in the eye stops further retinal damage
- reduced retinal swelling caused directly by oxygen induced vasoconstricion
- reduced bleeding by vasoconstriction and elimination of hemorrhagic damage by improved blood flow
- reduced inflammation and improved oxygen transport
- restored micro-circulation and blood flow to retina
- preservation and regeneration of the optic nerve
- decreased intraocular pressure
- reduced infection. Oxygen has bactericidal and bacteriostatic effect. Oxygen reduces infection by enhancing white blood cells phagocytosis and strengthening the effect of some antibiotics while protecting the body from the side effects
- improved visual acuity by preservation of retinal receptors and restored vision by all of the above
- reduced toxic effect by increased partial oxygen pressure and retinal oxygenation
- reduced scar formation following surgery
Infections involving the eye and the orbit
Eye infections can be result of injury, or compromised immune system in diabetics and post-surgical patients such as: cataract extraction and intraocular lens implantation. Hyperbaric oxygen has multiple effect on bacteria: HBO is bactericidal and bacteriostatic, enhances white blood cells phagocytosis, strengthens the effect of some antibiotics while protecting the body of the side effects.
Radiation-induced optic neuropathy, Diabetic retinopathy and Glaucoma
Optic neuropathy and glaucoma are both result of a damage of the optic nerve due to various reasons: increased intraocular pressure, radiation due to cancer, poor blood supply, inflammation of the nerve itself (optic neuritis) or supplying blood vessels, trauma or injury to the eye or intoxication (mostly methanol). Optic neuropathy and glaucoma which can result in sudden or gradual loss of vision can be treated with hyperbaric oxygen therapy. Hyperbaric oxygen can: prevent further optical nerve damage and start nerve regeneration, reduce retinal swelling, reestablish normal blood supply and down-regulate intraocular pressure.
Retinitis Pigmentosa is a progressive degenerative genetic eye disorder caused by loss or abnormality of eye photo receptors. Retinitis pigmentosa can lead to night blindness, tunnel vision or ultimately blindness. Hyperbaric oxygen therapy can save retinal receptors from deterioration and improve visual acuity.
Corneal disorders such as: keratitis, traumatic injuries and ulceration can benefit from antibacterial effect of hyperbaric oxygen and neovascularization. Hyperbaric oxygen therapy counteracts hypoxia, reduces corneal edema, and in case of surgery prevents scar formation.
- Weiss JN: Hyperbaric oxygen therapy and age-related macular degeneration: Undersea Hyperb Med; Mar-Apr;37(2):101-5, 2010.
- Miyamoto H, Ogura Y, Wakano Y, Honda Y: The long term results of hyperbaric oxygen treatment for macular edema with retinal vein occlusion; Nippon Ganka Gakkai Zasshi; Sep;97(9):1065-9 1993.
- Pfoff DS, Thom SR:Preliminary report on the effect of hyperbaric oxygen on cystoid macular edema; J Cataract Refract Surg;Mar;13(2):136-40, 1987.
- Jansen EC, Nielsen NV: Promising visual improvement of cystoid macular oedema by hyperbaric oxygen therapy; Acta Ophthalmol Scand, Aug;82(4):485-6, 2004.
- Miyamoto H, Ogura Y, Honda Y: Hyperbaric oxygen treatment for macular edema after retinal vein occlusion–fluorescein angiographic findings and visual prognosis; Nippon Ganka Gakkai Zasshi, Feb;99(2):220-5, 1995.
- Miyamoto H, Ogura Y, Wakano Y, Honda Y: The long term results of hyperbaric oxygen treatment for macular edema with retinal vein occlusion; Nippon Ganka Gakkai Zasshi; Sep;97(9):1065-9, 1993.
- Xu YN, Huang JG: Hyperbaric oxygen treatment for cystoid macular edema secondary to retinal vein occlusion; Zhonghua Yan Ke Za Zhi; Jul;27(4):216-8, 1991.
- Miyake Y, Awaya S, Takahashi H, Tomita N, Hirano K: Hyperbaric oxygen and acetazolamide improve visual acuity in patients with cystoid macular edema by different mechanisms; Arch Ophthalmol; Dec;111(12):1605-6,1993.
- Ogura Y, Kiryu J, Takahashi K, Honda Y: Visual improvement in diabetic macular edema by hyperbaric oxygen treatment; Nippon Ganka Gakkai Zassh; Sep;92(9):1456-60,1988.
- Ogura Y, Takahashi M, Ueno S, Honda Y: Hyperbaric oxygen treatment for chronic cystoid macular edema after branch retinal vein occlusion; Am J Ophthalmol; Sep 15;104(3):301-2,1987.
- Suttorp-Schulten MS, Riemslag FC, Rothova A, van der Kley AJ, Riemslag FC: Long-term effect of repeated hyperbaric oxygen therapy on visual acuity in inflammatory cystoid macular oedema; Br J Ophthalmol; Apr;81(4):329,1997.
- Krott R, Heller R, Heimann K: Adjuvant hyperbaric oxygen therapy (HBO) in cystoid macular edema–preliminary results; Klin Monbl Augenheilkd, Aug;215(2):144,1999.
- Kiryu J, Ogura Y: Hyperbaric oxygen treatment for macular edema in retinal vein occlusion: relation to severity of retinal leakage; Ophthalmologica; 210(3):168-70,1996.
- Johnson GP: Cases from the aerospace medicine residents’ teaching file. Case #38. A navigator with nonischemic central retinal vein occlusion progressing to ischemic central retinal vein occlusion; Aviat Space Environ Med; Oct;61(10):962-5,1990.
- Roy M, Bartow W, Ambrus J, Fauci A, Collier B, Titus J: Retinal leakage in retinal vein occlusion: reduction after hyperbaric oxygen; Ophthalmologica; 198(2):78-83,1989.
- Ogura Y, Takahashi M, Ueno S, Honda Y: Hyperbaric oxygen treatment for chronic cystoid macular edema after branch retinal vein occlusion; Am J Ophthalmol, Sep 15;104(3):301-2,1987.
- Gismondi A, Colonna S, Micalella F, Metrangolo C: Hyperbaric oxygen therapy in thrombotic occlusion of the central retinal vein; Minerva Med; May 31;72(22):1413-5,1981.
- Bojić L, Kovacević H, Andrić D, Romanović D, Petri NM.Hyperbaric oxygen dose of choice in the treatment of glaucoma; Arh Hig Rada Toksikol, Sep; 44(3):239-47,1993.
- Bojić L, Racic G, Gosović S, Kovacević H:The effect of hyperbaric oxygen breathing on the visual field in glaucoma; Acta Ophthalmol (Copenh); Jun, 71(3):315-9,1993.