Multifocal Stroke From Ozone Gas Emboli
Freund PR, Alshafai L, Margolin EA. Journal of Neuro-Ophthalmology, 2019.
- Study type
- Case report
- People studied
- 1 person
- Population
- 34-year-old man with chronic neck pain treated with regular cervical paravertebral ozone injections
- Published
- 2019, Journal of Neuro-Ophthalmology
- Identifiers
- PMID 30741783, DOI 10.1097/WNO.0000000000000754
What the authors reported
After his last cervical paravertebral ozone injection, a 34-year-old man treated regularly with such injections for chronic neck pain had a syncopal episode and woke with ataxia, aphasia, hemiparesis, and a left sixth nerve palsy. CT angiography showed gas inside the right vertebral artery, and brain MRI showed multiple posterior circulation infarcts.
What limits this result
Single case report, read from a four-sentence abstract only. The abstract gives no ozone dose or volume, number of injections, treatment of the stroke, or outcome, and it shows the event occurred, not how often it occurs.
Harms reported after ozone therapy, and studies of how ozone exposure affects health. One study rarely settles a medical question; our guides weigh each paper against the rest of the evidence.
How the study was done
- Design
- Case report (PubMed publication type)
- Setting
- Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Canada (affiliation of two of the three authors)
- Read from
- Read from the abstract only; where this page says nothing about an item, the abstract does not report it. Read on October 2, 2026.
Source: Abstract on PubMed
Study arms
| Group | Participants | What they received |
|---|---|---|
| Single patient: 34-year-old man with chronic neck pain | Not reported | Regular cervical paravertebral ozone injections |
Source: Abstract on PubMed
What it measured
- Events after the last injection
- Syncopal episode; on awakening, ataxia, aphasia, hemiparesis, and left sixth nerve palsy
- Computed tomographic angiography
- Intra-arterial gas in the right vertebral artery
- Brain MRI
- Multiple posterior circulation infarcts
- Authors' conclusion
- The case illustrates the potential dangers of paravertebral injections of ozone
Source: Abstract on PubMed
Safety as reported
Multifocal stroke from ozone gas emboli
Source: Abstract on PubMed
Where we cite this study
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