TLDR

• Delayed radiation injury — including radiation cystitis, osteoradionecrosis (ORN), and soft tissue necrosis — can surface months to decades after cancer treatment ends.
• These injuries occur because radiation permanently damages blood vessels, starving tissue of oxygen.
• Hyperbaric oxygen therapy (HBOT) is the only treatment that directly addresses this root cause by restoring oxygen to radiation-damaged tissue.
• HBOT is FDA-approved for delayed radiation injuries, covered by Medicare Part B and most PPO insurance plans.
• Clinical studies report 76–100% response rates for radiation-induced hemorrhagic cystitis.
• OxygenWell offers HBOT for radiation injuries in Sherman Oaks and Calabasas, CA. Call (818) 661-0939.

What Is Delayed Radiation Injury?

You beat cancer. Treatment is over. But months — or even years — later, new symptoms appear: blood in the urine, pelvic pain, chronic wounds that won't close, jaw pain, or rectal bleeding. This is delayed radiation injury.

Radiation therapy works by destroying cancer cells. But the high doses needed to eliminate malignant tissue also damage the blood vessels of nearby healthy tissue. This vascular damage doesn't always show up immediately. For many patients, the consequences unfold slowly — starving tissue of oxygen and triggering a cascade of chronic, progressive injury that can begin anywhere from 6 months to 20 years after treatment ends. The average onset is approximately 35 months after completing pelvic radiation.

Delayed radiation injury is not rare. Radiation cystitis, for example, occurs in roughly 6.5% of patients after pelvic radiation for prostate, bladder, rectal, or gynecologic cancers. Osteoradionecrosis of the jaw is a known complication of head and neck radiation. Soft tissue radionecrosis can develop anywhere in the radiation field — abdomen, pelvis, chest, neck.

Many patients and even their physicians don't connect these symptoms to radiation received years earlier. They go undiagnosed and undertreated, living with chronic pain and disability when an FDA-approved solution exists.

What Conditions Does HBOT Treat?

HBOT is FDA-approved for delayed radiation injuries as a category, which includes:

Radiation Cystitis (Hemorrhagic Cystitis)

Bladder inflammation and bleeding caused by radiation damage to the bladder wall. Symptoms include blood in the urine (hematuria), urinary urgency, frequency, burning, and nocturia. Most commonly occurs after pelvic radiation for prostate, bladder, cervical, or rectal cancers.

Osteoradionecrosis (ORN)

Radiation-induced bone death, most commonly in the jaw after head and neck cancer treatment. Symptoms include jaw pain, non-healing wounds in the mouth, exposed bone, and difficulty eating. HBOT is used both before and after surgical intervention — the Marx Protocol — which reduced ORN incidence from 29.9% to 5.4% in landmark research.

Soft Tissue Radionecrosis (STNR)

Chronic non-healing wounds, ulcers, and tissue breakdown in areas exposed to radiation — including the chest wall, abdomen, pelvis, and neck. HBOT stimulates angiogenesis and collagen formation to restore tissue viability.

Radiation Proctitis

Rectal inflammation, bleeding, and cramping following pelvic radiation. HBOT addresses the underlying tissue hypoxia driving chronic proctitis.

Radiation-Induced Laryngeal and Soft Tissue Necrosis

Non-healing injuries in the throat, neck, and surrounding structures after head and neck radiation.

Why Does Radiation Cause Long-Term Tissue Damage?

High-dose radiation damages the small blood vessels (arterioles and capillaries) in the treatment field. Over time, these vessels become fibrotic — stiffened and narrowed — a process called obliterative endarteritis. As the vascular supply deteriorates, the tissue becomes chronically hypoxic: starved of the oxygen it needs to maintain itself, repair damage, and fight infection.

This tissue hypoxia is self-perpetuating. Hypoxic tissue cannot generate the cellular energy needed for healing. Fibroblasts fail to function. New blood vessel growth stalls. The tissue progressively deteriorates, developing ulcers, necrosis, and chronic inflammation. This is why conventional treatments — antibiotics, wound care, irrigation — so often fail. They treat the surface. They don't address the oxygen deficit driving the injury.

How Does HBOT Heal Radiation Tissue Damage?

HBOT works at the root cause: restoring oxygen to chronically hypoxic, radiation-damaged tissue. Inside our Fortius 420 monoplace chambers, patients breathe 100% medical-grade oxygen at pressures up to 2.4 ATA. At this pressure, oxygen dissolves directly into the blood plasma and penetrates tissue at concentrations 10–15x higher than normal — flooding oxygen-starved tissue with the fuel it needs to begin healing.

The physiological effects of HBOT on radiation-injured tissue are well-documented:

• Angiogenesis: HBOT triggers VEGF production, stimulating new capillary growth into previously avascular scar tissue. Each course of HBOT can increase capillary density in radiation-damaged tissue by 8–10x.
• Collagen synthesis: With oxygen restored, fibroblasts resume collagen production — rebuilding the structural matrix needed for tissue repair and wound closure.
• Stem cell mobilization: HBOT increases circulating CD34+ stem cells up to 8x baseline after 20 sessions, driving tissue regeneration from within.
• Antimicrobial effect: Elevated tissue oxygen restores neutrophil killing capacity, reducing bacterial burden in chronic wounds.
• Reduction of inflammation: HBOT down-regulates inflammatory cytokines and reduces tissue swelling, decreasing pain and improving function.

What Are the Success Rates?

The clinical evidence for HBOT in radiation injuries is strong and spans decades of peer-reviewed research.

• Multiple studies report response rates of 76–100% for radiation-induced hemorrhagic cystitis.
• The landmark RICH-ART randomized controlled trial (The Lancet eClinicalMedicine, 2025) confirmed HBOT's long-term efficacy for radiation-induced cystitis.
• The Marx Protocol reduced osteoradionecrosis incidence from 29.9% to 5.4% — an over 80% reduction in complication rate. (Marx RE et al., 1985)
• A 2025 systematic review in CA: A Cancer Journal for Clinicians confirmed HBOT's clinical benefit across radiation cystitis, ORN, and soft tissue necrosis.
• A 2023 retrospective cohort study in Frontiers in Oncology documented significant symptom improvement in radiation-induced proctitis over 10 years of clinical experience.

How Many HBOT Sessions Are Needed?

Treatment protocols vary based on the type and severity of radiation injury. General guidelines used at OxygenWell:

• Radiation Cystitis: 2.0–2.4 ATA, 90 min, 5x/week, 30–60 sessions
• Osteoradionecrosis (ORN): Marx Protocol — 20 pre-op + 10 post-op sessions at 2.4 ATA
• Soft Tissue Radionecrosis: 2.0–2.4 ATA, 90 min, 20–60+ sessions
• Radiation Proctitis: 2.0–2.4 ATA, 90 min, 30–40 sessions

Most patients begin to notice symptom improvement within the first 10–20 sessions, with continued improvement through the full course. Earlier treatment — before injury becomes severe — is associated with better outcomes. Every patient at OxygenWell receives a personalized protocol developed by our medical team.

Is It Too Late to Treat? What If Years Have Passed?

This is one of the most common questions patients ask. The short answer: it is almost never too late.

Delayed radiation injuries are, by definition, late-appearing conditions. Patients have been successfully treated with HBOT 5, 10, even 20 years after completing radiation. The oxygen deficit in radiation-damaged tissue persists indefinitely unless addressed — and HBOT can begin the reversal process at any point.

What does affect outcomes is the severity of injury at the time of treatment. Moderate-grade injuries respond more robustly than end-stage tissue necrosis. This is why early evaluation matters: if you are experiencing symptoms that could indicate radiation injury, an evaluation sooner rather than later gives the best chance at full recovery.

If you are a cancer survivor experiencing chronic pain, bleeding, non-healing wounds, or deteriorating tissue in or near a prior radiation field, contact us at (818) 661-0939 for a consultation.

Does Insurance Cover HBOT for Radiation Injuries?

Yes. HBOT for delayed radiation injuries is FDA-approved and covered by Medicare Part B and most PPO insurance plans. Covered radiation injury diagnoses include radiation cystitis, osteoradionecrosis, soft tissue radionecrosis, and radiation-induced non-healing wounds.

OxygenWell is an insurance-approved facility. We handle all insurance pre-authorizations through our dedicated billing team. Medicare patients typically pay 20% of the approved amount after the Part B deductible.

What to Expect at OxygenWell

OxygenWell is a physician-owned hyperbaric oxygen therapy clinic in Sherman Oaks and Calabasas, CA. With 12+ years dedicated to hyperbaric medicine and 50,000+ supervised HBOT sessions, we bring deep clinical experience to every radiation injury case.

• Medical-grade oxygen at up to 2.4 ATA — fully rated Fortius 420 monoplace chambers. Most centers only reach 1.3–1.5 ATA, which is insufficient for radiation injuries.
• Personalized medical protocols — every patient receives a protocol tailored to their specific injury, cancer history, and health status.
• Insurance expertise — we handle pre-authorization for Medicare and PPO plans.
• Extended hours — including evenings and weekends.
• Integrative support — we can combine HBOT with photobiomodulation (red light therapy) and functional medicine support to optimize healing outcomes.

"We don't just meet the standard. We exceed it — for your safety, your results, and your peace of mind."

Frequently Asked Questions

Can HBOT treat radiation injuries that occurred years ago?

Yes. HBOT can address the underlying tissue hypoxia driving radiation injury regardless of how much time has passed. While earlier intervention produces better outcomes, patients have responded to HBOT 10–15 years post-radiation.

How do I know if my symptoms are from radiation injury?

Common indicators include blood in the urine after pelvic radiation, jaw pain or exposed bone after head/neck radiation, non-healing wounds in the radiation field, rectal bleeding, or progressive pain in previously irradiated areas. A consultation with our medical team can clarify your situation.

Is HBOT safe for cancer survivors?

Current evidence does not show that HBOT promotes cancer growth or recurrence. HBOT is routinely used in cancer survivors and is specifically FDA-approved for radiation-related complications.

Does OxygenWell treat both radiation cystitis and osteoradionecrosis?

Yes. We treat the full spectrum of FDA-approved delayed radiation injuries, including radiation cystitis, osteoradionecrosis, soft tissue radionecrosis, and radiation-induced wounds.

Take the Next Step

If you or a patient is living with the late effects of radiation therapy, HBOT may offer meaningful relief — and insurance likely covers it.

OxygenWell | Sherman Oaks & Calabasas, CA
Call (818) 661-0939 or visit oxygenwell.com to schedule a consultation.

OxygenWell is a physician-owned hyperbaric and regenerative medicine clinic. Dr. Beth Meneley, DAOM, L.Ac., brings 25+ years in integrative medicine and 12+ years dedicated to hyperbaric medicine in Los Angeles.