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A 38-year-old man with bilateral foveal hemorrhages
Digital Journal of Ophthalmology 2008
Volume 14, Number 7
March 11, 2008
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| Diagnosis and Discussion | A diagnosis of high-altitude retinopathy (HAR) was made in this case. HAR is an acquired vascular retinopathy that develops at high altitudes, typically above 16000 feet (approximately 4900m).(1) Its features include dilated retinal veins, intraretinal and preretinal hemorrhages and optic disc hyperemia. Often these hemorrhages spare the macula, although in this case both foveae were affected.
A number of factors are thought to contribute to the pathophysiology of the condition including increased retinal blood flow associated with reduced arterial oxygen pressures, reduced vascular competence (2) and inadequate autoregulation of the retinal circulation in hypoxic conditions.(3) It has also been found to be more common in those with higher baseline intraocular pressures and those who have used non-steroidal anti-inflammatory drugs.(2)
The Valsalva maneuver (forcible exhalation against a closed glottis) can be associated with a retinopathy characterized by rupture of perifoveal capillaries and unilateral or bilateral pre-macular hemorrhages. It has been suggested that this maneuver contributes to the pathophysiology of HAR but the intraretinal hemorrhage, retinal venous dilation and optic disc edema which may be seen in HAR are not features of Valsalva retinopathy.(4)
HAR has a benign course and usually is associated with good long-term visual outcomes. However, high altitude retinopathy is part of a spectrum of life threatening conditions which constitute altitude sickness. These conditions are acute mountain sickness (AMS), high-altitude retinopathy, high-altitude cerebral edema (HACE) and high-altitude pulmonary edema (HAPE). High-altitude retinopathy is associated with HACE. The presence of retinopathy findings in climbers should alert physicians to the possibility of cerebral edema.(1)
Treatment for HAR alone is rarely required but treatment of the systemic altitude sickness may include descent, administration of oxygen, steroids or diuretics.(1) | |
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