Physiological Basis Of Hyperbaric Oxygen Therapy (HBOT)
For Ophthalmology

Sequelae of the eye can cause devastating vision loss and blindness as well as loss of independence severely impacting any individual, their family and the health care system.

The conditions for which HBO therapy has shown clear scientific evidence are:

    • Decompression sickness or arterial gas embolism with visual signs or symptoms. (1)
    • Central retinal artery occlusion.
    • Ocular and periocular gas gangrene.
    • Cerebro-rhino-orbital mucormycosis.
    • Periocular necrotizing fasciitis.
    • Carbon monoxide poisoning with visual sequelae.
    • Radiation optic neuropathy.
    • Radiation or mitomycin C-induced scleral necrosis.
    • Periorbital reconstructive surgery.
  • Radiation induced macular ischemia. (2)

The authors then suggest that several other ocular disorders, such as macular degeneration and others, including some causing vision loss, which may benefit from HBOT.
The range where HBO may be effective is broad; from ischemic events of the eye to periocular brown recluse spider envenomation.

At sea level (1.0 ATA), breathing room air, arterial PO2 is approximately 100 mmHg and hemoglobin saturation is approximately 100%. When breathing 100% oxygen at greater pressures than 1.0 ATA, this additional oxygen supersaturates the hemoglobin of the red blood cells forcing the oxygen to dissolve into plasma, (3) tissues, organs (here we include our eyes) to create microvasularization or angiogenesis.

The arterial supply to the eye is via the ophthalmic artery, a branch of the internal carotid artery.
The ophthalmic artery branches to supply areas around the eyes including the optic nerve. (4)


A Stroke to the Eye; Central Retinal Artery Occlusion (CRAO)
This beautiful photo shows the central retinal artery with it’s branches around the eye.

CRAO is potentially devastating and IS an ocular emergency
because it can cause blindness.

CRAO is the ocular analogue of a cerebral stroke. (5) CRAO needs to follow the same principles of treatment as any other vascular end organ ischemic disease. That is, to attempt to reperfuse ischemic tissue as quickly as possible and to prevent a cascade of secondary inflammatory events early.
As stated earlier, the retina has a dual blood supply. HBOT may enable the secondary, choroidal circulation to supply the oxygen needs of the entire retina in CRAO. Since CRAO is often transient, this phenomenon many enable the retina to survive the period of occluded blood flow.
Retinal venous hemoglobin oxygen saturation has been shown to increase from 58% (breathing room air) to 94% in 100% hyperbaric oxygen environment. (6)

HBOT is considered acceptable, safe and effective and will assist to increase the partial pressure of oxygen delivery to ischemic tissue until spontaneous or assisted reperfusion occurs.

Because vision is an emergency, best results for vision restoration occur when oxygen therapy is given within the first 8 hours of vision loss and continued till vision resumes. Good results have also been seen if HBOT is administered within the first 24 hours. (7)
Minimal results may be seen after that depending on each patient’s own physiology.

Once Blind, her eye can now see. Read on for Lisa’s testimony of how Hyperbaric Oxygen Therapy restored her vision after her “stroke to her eye.”
Additional occurrences such as post radiation injury and age-related macular degeneration can cause vision loss due to lack of oxygen and/or injury to the retina.

HBOT positively impacts the retinal cells increasing vision possibility. Because cells of the retina are specialized neurons; actually an extension of the brain, retinal cells respond to HBOT, similarly to brain-injured patients. Oxygen transport is significantly increased with HBOT, supersaturating these organs to bring healing and restoration of function. (8)

Post Radiation use of HBOT: Radiation-induced optic neuropathy (RON or RION) is one of the most common complications that may occur in patients treated with radiotherapy for nasopharyngeal carcinoma (NPC) and other intracranial tumours. (9)
Vison loss is a devastating consequence post radiotherapy for treatment of these cancers. RON may occur months to years after the radiation treatment. To be most effective, HBO has to be initiated as soon after the onset of vision loss as possible. (10)

Here is a testimony of a 41 year old woman presenting with severe visual impairment after 4 years after her radiation therapy. HBOT was promptly instituted when other therapies failed and her vision as well as the quality of her life steadily started to improve. This improvement was documented and confirmed by her progressive recovery of the visual field in her right eye and the changes in her sequential follow-up MR scanning. (11)

HBOT and Macular Degeneration: Age-related macular degeneration (AMD) is a significant cause of visual loss in the United States and Western Europe. As the population ages, the prevalence rate of advanced AMD is expected to double by 2030. A trial treating 14 patients with advanced AMD was done using HBOT for 60 minutes. To read more …. Significant improvements in visual acuity and/or visual field, with improvements in the activities of daily living were observed. HBOT in a monoplace chamber, combined with other therapies offers hope for additional benefit.
More reasons Why Hyperbaric Oxygen Therapy (HBOT) is effective:
Read these 22 reasons that HBOT can help you.
For wound healing, HBOT will increase growth factors, endothelial progenaitor cells (EPCs), and stem cell production. (12)
HBOT is given in a hard steel medical grade device called a Hyperbaric chamber. HBOT has been defined The Undersea and Hyperbaric Medicine Society, as breathing 100% oxygen at a pressure greater than one atmosphere absolute (ATA). (13)

The team of dynamic professionals that make up Advanced Hyperbaric Recovery
Our award winning facility is conveniently located 10 miles north of the Golden Gate Bridge in our beautiful San Francisco Bay Area. We would love for you to come and tour our facility.

We charge a fraction of the cost, using the same style chambers as a hospital-based Hyperbaric unit.

Several Eye Diseases are covered by your Insurance. We will prepare the most recent research for your specific diagnosis whenever available.
If YOU or anyone in your family
or anyone in your community might be a candidate, whose quality of life may be greatly improved for with Hyperbaric Oxygen Therapy, Please consider this remarkable medicine today.
Call us today for more information or to schedule a consultation with our Medical Hyperbaric Physician.
415-785-8652

Advanced Hyperbaric Medical Director, Jacqueline S. Chan, DO
Hyperbaric Physician is Board Certified in Neuromusculoskeletal Medicine and Family Practice
Dr. Chan shares some tips for this cold and flu season.


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