This is known as Uhthoff's phenomenon
and the increase in temperature is believed to slow or block the nerve conduction, temporarily exacerbating neurological symptoms.
Patients may also present with Uhthoff's phenomenon
, a worsening of neurological symptoms as body heat increases, perhaps with even subtle changes in temperature affecting performance.
Known as Uhthoff's phenomenon, after the physician who first discovered it in 1889, heat sensitivity affects people with MS and other demyelinating diseases.
Frohman says she and her colleagues have found that Ampyra, a type of 4-AP approved by the Food and Drug Administration for gait-related issues, is also effective for Uhthoff's phenomenon, although it's not specifically approved for that use.
Researchers at the University of Texas Southwestern Medical Center in Dallas studied an aspect of MS called Uhthoff's phenomenon
, named after a German ophthalmologist who reported in 1889 that some people have temporary vision problems after exercise or in hot weather.
Additional associated clinical findings include: a reduction in vision in bright light; Uhthoff's phenomenon, exercise- or heat-induced exacerbation of visual symptoms described in 50% of patients with isolated ON; (23) and the Pulfrich phenomenon, in which anomalous perception of the direction of movement of an object occurs due to asymmetry of conduction velocity in the optic nerves.
(71) Patients can alleviate Uhthoff's phenomenon by remaining indoors on hot and humid days and drinking plenty of cool fluids, but principally they need to be reassured that Uhthoff's symptoms are entirely reversible and not damaging to vision.
A A woman aged 31 presents with unilateral loss of vision, deteriorating over three days with orbital pain increasing with eye movement, antecedent coryza, positive Pulfrich and Uhthoff's phenomenon
and Lhermitte's symptom.
* This condition is known as Uhthoff's phenomenon
and was later found to be caused by a rise in body temperature