Hemodynamic And Thermal Responses To Head And Neck Cooling In Men And Women
Ku YT, Montgomery LD, Webbon BW
Am J Phys Med Rehabil 1996 Nov-Dec;75(6):443-50
Lockheed Martin Engineering and Sciences, NASA Ames Research Center, Moffett Field, CA 94035, USA
PMID# 8985108; UI# 97138082
Personal cooling systems are used to alleviate symptoms of Multiple Sclerosis and to prevent increased core temperature during daily activities.
The objective of this study was to determine the operating characteristics and the physiologic changes produced by short term use of one commercially available thermal control system.
A Life Support Systems, Inc. Mark VII portable cooling system and a liquid cooling helmet were used to cool the head and neck regions of 12 female and 12 male subjects (25-55 yr) in this study.
The healthy subjects, seated in an upright position at normal room temperature (approximately 21 degrees C), were tested for 30 min with the liquid cooling garment operated at its maximum cooling capacity.
Electrocardiograms and scalp and IntraCranial blood flows were recorded periodically during each test sequence.
Scalp, right and left ear, and oral temperatures and cooling system parameters were logged every 5 min.
Scalp, right and left ear canal, and oral temperatures were all significantly (P <0.05) reduced by 30 min of head and neck cooling.
Oral temperatures decreased approximately 0.2-0.6 degrees C after 30 min and continued to decrease further (approximately 0.1-0.2 degrees C) for a period of approximately 10 min after removal of the cooling helmet.
IntraCranial blood flow decreased significantly (P < 0.05) during the first 10 min of the cooling period.
Both right and left ear temperatures in the women were significantly lower than those of the men during the cooling period.
These data indicate that head and neck cooling may be used to reduce core temperature to that needed for symptomatic relief of both male and female Multiple Sclerosis patients.
This study quantifies the operating characteristics of one liquid cooling garment as an example of the information needed to compare the efficiency of other garments operated under different test conditions.
Lowering Body Temperature With A Cooling Suit As Symptomatic Treatment For Thermosensitive Multiple Sclerosis
Capello E, Gardella M, Leandri M, Abbruzzese G, Minatel C, Tartaglione A, Battaglia M, Mancardi GL
Ital J Neurol Sci 1995 Nov;16(8):533-9
Universita di Genova, Dipartimento di Scienze Neurologiche e CNR, Italy
PMID# 8613414; UI# 96188454
A cooling system (Mark VII Microclimate System) was used to give six ThermoSensitive Multiple Sclerosis patients two 45-minute daily coolings for a period of one month.
Before the first cooling, a baseline clinical and ElectroPhysiological examination was performed.
The same tests were repeated after the first application and after the thirtieth cooling day, thus providing information relating to acute and chronic efficacy.
A clinical improvement was observed after both acute and, more unexpectedly, chronic cooling, whereas a significant improvement in Central SomatoSensory Conduction was recorded only under acute conditions.
Our data suggest that cooling with this device leads to an improvement in some functional performances (mainly Fatigue and strength) of about two hours' duration in ThermoSensitive patients.
Laryngeal Uhthoff's Phenomenon: A case report
Pringle CE, McEwan LM, Ebers GC
Mult Scler 1995 Nov;1(3):163-4
Univ of Ottawa, Division of Neurology, Ontario, Canada
PMID# 9345447; UI# 98005307
An Uhthoff-like phenomenon was recently observed in a patient with Clinically Definite MS who experienced transient Dysphonia brought on by exertion and relieved by cooling.
The patient's Dysphonia was felt to be related to intermittent temperature-dependent Conduction Block associated with a DeMyelinating plaque in the region of the left Nucleus Ambiguus.
We have termed the patient's Intermittent Dysphonia 'Laryngeal Uhthoff's Phenomenon'.
Thermal Sensitivity In DeMyelinating Neuropathy
Chaudhry V, Crawford TO, DeRossett SE
Muscle Nerve 1993 Mar;16(3):301-6
Johns Hopkins Univ, School of Medicine, Dept of Neurology, Baltimore, Maryland
PMID# 8446129; UI# 93188906
An 8-year-old girl with DeMyelinating Peripheral Neuropathy was observed to get markedly weak coincident with a febrile illness.
With return of body temperature to normal over 24 hours, her strength improved back to baseline.
Subsequently, we studied the effect of temperature on CMAP amplitude of two Motor Nerves in the patient and two control subjects.
Both temperature, measured orally, was raised by immersing the subjects in hot water and lowered by passive cooling.
With increase in temperature to 39.5 degrees C, the CMAP amplitudes were reduced by 80% in the patient's nerves compared to only 48% in the control nerves. These changes recovered with cooling to 36.9 degrees C.
We conclude that DeMyelinated Peripheral Nerves are more susceptible to temperature-induced impulse blocking than healthy nerves.
And provide the first published evidence of the clinical consequences of this phenomenon in a DeMyelinating disease other than Multiple Sclerosis.
- Muscle Nerve 1995 Jun;18(6):674-5
Increased Visual Impairment After Exercise (Uhthoff's Phenomenon) In Multiple Sclerosis: Therapeutic Possibilities
van Diemen HA, van Dongen MM, Dammers JW, Polman CH
Eur Neurol 1992;32(4):231-4
Free Univ Hospital Amsterdam, Dept of Neurology, The Netherlands
PMID# 1324180; UI# 92371537
The Uhthoff Symptom, a transient impairment of Visual function after exercise, is demonstrated in 2 Multiple Sclerosis patients.
Following exercise, impairment of Visual function, as documented most clearly by the testing of contrast sensitivity, was less obvious after body surface cooling and after treatment with orally administered 4-AminoPyridine.
It is hypothesized that both treatment modalities improve the Nerve conduction safety factor and thereby prevent the occurrence of a Conduction Block, which is believed to be the mechanism underlying the Uhthoff Symptom.