Maturitas, 1 (1979) 201-205 0 Elsevier/North-Holland Biomedical Press
201
THERMOGRAPHY OF MENOPAUSAL HOT FLUSHES
DAVID W. STURDEE ’ and BARRIE L. REECE 2 t UniversityDepartment of Obstetricsand Gynaecology, Birmingham Maternity Hospital, Birmingham, B1.5 2TG, United Kingdom; 2 Regional RadtWon Physics and Protection Service, Queen Elizabeth Medical Centre, Birmingham, BI5 2TH, United Kingdom (Received 2 August 1978, accepted 8 November 1978)
The skin temperature changes associated with menopausal hot flushes have been examined by thermography on a smalI group of patients. The subjective sensation of heat during a flush seems to be out of proportion to the actual skin temperature increase which was only about 1°C on the face, neck and upper chest during this study. The increased temperature on the cheeks often persisted for several minutes after the symptoms of the flush had subsided, whereas sweating on the forehead produced a more rapid local cooling effect. Sequential temperature changes were portrayed by using an AGA Thermovision Model 680 Medical System with a colour isotherm attachment. This study provided colourful objective evidence that the symptom of menopausal flushing is associated with an increase of skin temperature which may be monitored by thermography. (Key words: Menopause, Hot flush, Thermography)
INTRODUCTION
The hot flush is universally recognised by both the medical profession and lay public as the most characteristic and often the most distressing symptom of the climacteric, yet it has received remarkably little scientific investigation. As part of a study of several aspects of the hot flush we have used thermography [1,2] to demonstrate the skin temperature changes. METHODS
Volunteer subjects were obtained from the menopause research clinic at the Birmingham and Midland Hospital for Women. To date there have only been four women who have had sufficiently frequent hot flushes and who have agreed to take part in the study. Each subject was seated in a chair and was naked to the waist. Room temperature was maintained between 18-20°C and 15 min were allowed for the body surface temperature to stabilise and reach equilibrium with the room temperature [l] before commencing the study. Thermogram pictures were taken with an AGA Thermovision Model 680 Present address: David W. Sturdee, Department of Obstetrics and Gynaecology, Coventry, CV2 2DX, United Kingdom.
Walsgrave Hospital,
Fig. 1. Thermograms of a menopausal woman before (A) and during (B) a hot flush. The temperature scale of the isotherms is indicated beneath the thermograms increasing from left to right by about 1°C for each colour. The dark blue isotherm is just off the scale to the left. The green isotherm was equivalent to 32“C. (Published in Modern Medicine of Great Britain, June, 1978.)
203
Fig. 2. T hermograms of the face and neck of a menopausal woman before (A), during the initia 11sensatic,n of flushing (B), and after 60 set of the flush (C). The yellow isotherm was equival lent to 341°C.
204
Medical Camera System, which had a colour isotherm camera attachment using Polaroid film. A few resting thermograms were taken so that the temperature range and degree of separation of the isotherms could be adjusted appropriately. Temparature of the individual isotherms were standard&d by comparison with a black body reference source set at a constant temperature. Thermograms were taken at 5-min intervals to provide a firm base line in anticipation of a flush and more frequently when a flush was experienced. RESULTS
In some cases the flush was so mild that the thermographic changes were equivocal. One subject did not experience any flushes during a 3-h period of study. The thermograms of one subject (age 52 yr) before and during a hot flush are shown in Fig. 1. The resting thermogram indicates the skin temperature variation of the upper chest, shoulders, neck and face of the subject before she experienced a flush. The areas of black between the isotherms indicate that the temperature is between that of the two bordering isotherms. The warmest parts are the pink areas just below the left eye and right nostril, and on the trunk the supraclavlcular fossae are typically warmer than the surrounding skin and are shown as “islands” of green among the red isotherms. The other thermogram was taken just a few seconds after the subjective sensation of flushing though apart from a slightly pinker appearance around the neck there was no striking objective visual evidence of the flush. However, the thermogram is very different from the resting picture. On the chest the blue isotherm has been displaced by red, the red isotherm by green and a pink isotherm now indicates the position of the supraclavicular fossae. On the face the cheeks and forehead show the greatest change with a considerable increase in the size of the pink isotherm. This thermogram demonstrates, therefore, an overall increase of skin temperature of about 1°C during the flush which occurred within lo-15 set of the initial subjective feeling of warmth. On this occasion the sensation of the flush lasted for about 45 set, though even over 1 min later further thermograms showed no temperature change from the mid-flush picture. The subject whose thermograms are shown in Fig. 2 did not show any significant thermographic changes on the trunk during a flush and so the investigation was concentrated solely on her face. In order to provoke a satisfactory flush it was necessary to give her a few sips of warm tea; as a result her lips appear much warmer than they would usually be relative to the rest of her face. (The temperature effect on the rest of the body due to the thermal capacity of the tea is negligible.) The middle thermogram taken during the early part of the flush shows a temperature increase on the forehead with the appearance of yellow isotherms and a slight increase also on both cheeks shown by an extension of the red isotherms. The other areas do not show any marked temperature changes. In the bottom thermogram taken 60 set later both cheeks have become even warmer with the left showing the green isotherm and being warmer than the right. However, the forehead has become cooler with loss of the yellow and the appearance of some pink isotherms. This diversity between the cheek and forehead temperatures is explained by the cooling effect of sweating which was easily visible on the forehead, whereas on the cheeks, which contain few sweat glands, the temperature remains elevated. Although the main subjective sensation of heat was often located on the cheeks and forehead, the
cheek skin temperature which increased from 30-31°C the rest of the face which was about 32-33°C.
was always lower than most of
DISCUSSION
A major reason for the few studies of the hot flush to date is the lack of suitable volunteers [4] and the unpredictable frequency of flushing. Molnar [4] only obtained one subject during 18 mth of investigation and of the four women in this study only two experienced florid hot flushes during the period of observation. However, all the subjects commented that although they would usually expect between S-10 flushes during the morning, the experimental conditions of the study considerably reduced the frequency of flushing. Thermography has provided some colourful objective evidence of acute skin temperature changes associated with the onset of a hot flush. Previous studies using conventional thermometers or thermocouples [3,4] have also reported temperature increases of between 0.5-2°C on the cheek though Molnar [4] found that there were increases of up to 5°C in the fingers and toes. However, the symptom of flushing is usually experienced mainly in the face, neck and upper trunk and it would seem that the subjective sensation of heat is out of proportion to the actual temperature increase, which was only about 1“C in these areas studied. Furthermore, the temperature increase often persisted for several minutes after the sensation of warmth had passed, indicating that the flush is only experienced while the skin temperature is increasing. The severity of the sensation is, therefore, probably related to the rate of change of temperature as well as the actual temperature increase. This study was part of a larger investigation of several aspects of the hot flush some of which have already been reported [5]. ACKNOWLEDGEMENTS
We are grateful to Syntex Pharmaceuticals us (D.W.S.) during this study.
Limited for the financial support of one of
REFERENCES [ l] Park, W.M. and Reece, B.L. (1976) l%mdamental aspects of medical thermography, Teaching Booklet No. 3, British Institute of Radiology, London. [2] Proceedings of 1st European Congress on Thermography, Amsterdam, 1974. Bibliotheca Radiologica, No. 6, Karger, Basei, 1975. [ 31 Collett, M.E. (1949) Basal metabolism at the menopause. J. Appl. Physiol. 1,629-636. (4) Molnar, G.W. (1975) Body temperature during menopausal hot flushes. J. Appl. Physiol. 38,499503. [S J Sturdee, D.W., Wilson, K., Pilipi, E. and Cracker, A.D. (1978) Physiological aspects of menopausal hot flush. Br. Med. J. 2,79-80.
201
THERMOGRAPHY OF MENOPAUSAL HOT FLUSHES
DAVID W. STURDEE ’ and BARRIE L. REECE 2 t UniversityDepartment of Obstetricsand Gynaecology, Birmingham Maternity Hospital, Birmingham, B1.5 2TG, United Kingdom; 2 Regional RadtWon Physics and Protection Service, Queen Elizabeth Medical Centre, Birmingham, BI5 2TH, United Kingdom (Received 2 August 1978, accepted 8 November 1978)
The skin temperature changes associated with menopausal hot flushes have been examined by thermography on a smalI group of patients. The subjective sensation of heat during a flush seems to be out of proportion to the actual skin temperature increase which was only about 1°C on the face, neck and upper chest during this study. The increased temperature on the cheeks often persisted for several minutes after the symptoms of the flush had subsided, whereas sweating on the forehead produced a more rapid local cooling effect. Sequential temperature changes were portrayed by using an AGA Thermovision Model 680 Medical System with a colour isotherm attachment. This study provided colourful objective evidence that the symptom of menopausal flushing is associated with an increase of skin temperature which may be monitored by thermography. (Key words: Menopause, Hot flush, Thermography)
INTRODUCTION
The hot flush is universally recognised by both the medical profession and lay public as the most characteristic and often the most distressing symptom of the climacteric, yet it has received remarkably little scientific investigation. As part of a study of several aspects of the hot flush we have used thermography [1,2] to demonstrate the skin temperature changes. METHODS
Volunteer subjects were obtained from the menopause research clinic at the Birmingham and Midland Hospital for Women. To date there have only been four women who have had sufficiently frequent hot flushes and who have agreed to take part in the study. Each subject was seated in a chair and was naked to the waist. Room temperature was maintained between 18-20°C and 15 min were allowed for the body surface temperature to stabilise and reach equilibrium with the room temperature [l] before commencing the study. Thermogram pictures were taken with an AGA Thermovision Model 680 Present address: David W. Sturdee, Department of Obstetrics and Gynaecology, Coventry, CV2 2DX, United Kingdom.
Walsgrave Hospital,
Fig. 1. Thermograms of a menopausal woman before (A) and during (B) a hot flush. The temperature scale of the isotherms is indicated beneath the thermograms increasing from left to right by about 1°C for each colour. The dark blue isotherm is just off the scale to the left. The green isotherm was equivalent to 32“C. (Published in Modern Medicine of Great Britain, June, 1978.)
203
Fig. 2. T hermograms of the face and neck of a menopausal woman before (A), during the initia 11sensatic,n of flushing (B), and after 60 set of the flush (C). The yellow isotherm was equival lent to 341°C.
204
Medical Camera System, which had a colour isotherm camera attachment using Polaroid film. A few resting thermograms were taken so that the temperature range and degree of separation of the isotherms could be adjusted appropriately. Temparature of the individual isotherms were standard&d by comparison with a black body reference source set at a constant temperature. Thermograms were taken at 5-min intervals to provide a firm base line in anticipation of a flush and more frequently when a flush was experienced. RESULTS
In some cases the flush was so mild that the thermographic changes were equivocal. One subject did not experience any flushes during a 3-h period of study. The thermograms of one subject (age 52 yr) before and during a hot flush are shown in Fig. 1. The resting thermogram indicates the skin temperature variation of the upper chest, shoulders, neck and face of the subject before she experienced a flush. The areas of black between the isotherms indicate that the temperature is between that of the two bordering isotherms. The warmest parts are the pink areas just below the left eye and right nostril, and on the trunk the supraclavlcular fossae are typically warmer than the surrounding skin and are shown as “islands” of green among the red isotherms. The other thermogram was taken just a few seconds after the subjective sensation of flushing though apart from a slightly pinker appearance around the neck there was no striking objective visual evidence of the flush. However, the thermogram is very different from the resting picture. On the chest the blue isotherm has been displaced by red, the red isotherm by green and a pink isotherm now indicates the position of the supraclavicular fossae. On the face the cheeks and forehead show the greatest change with a considerable increase in the size of the pink isotherm. This thermogram demonstrates, therefore, an overall increase of skin temperature of about 1°C during the flush which occurred within lo-15 set of the initial subjective feeling of warmth. On this occasion the sensation of the flush lasted for about 45 set, though even over 1 min later further thermograms showed no temperature change from the mid-flush picture. The subject whose thermograms are shown in Fig. 2 did not show any significant thermographic changes on the trunk during a flush and so the investigation was concentrated solely on her face. In order to provoke a satisfactory flush it was necessary to give her a few sips of warm tea; as a result her lips appear much warmer than they would usually be relative to the rest of her face. (The temperature effect on the rest of the body due to the thermal capacity of the tea is negligible.) The middle thermogram taken during the early part of the flush shows a temperature increase on the forehead with the appearance of yellow isotherms and a slight increase also on both cheeks shown by an extension of the red isotherms. The other areas do not show any marked temperature changes. In the bottom thermogram taken 60 set later both cheeks have become even warmer with the left showing the green isotherm and being warmer than the right. However, the forehead has become cooler with loss of the yellow and the appearance of some pink isotherms. This diversity between the cheek and forehead temperatures is explained by the cooling effect of sweating which was easily visible on the forehead, whereas on the cheeks, which contain few sweat glands, the temperature remains elevated. Although the main subjective sensation of heat was often located on the cheeks and forehead, the
cheek skin temperature which increased from 30-31°C the rest of the face which was about 32-33°C.
was always lower than most of
DISCUSSION
A major reason for the few studies of the hot flush to date is the lack of suitable volunteers [4] and the unpredictable frequency of flushing. Molnar [4] only obtained one subject during 18 mth of investigation and of the four women in this study only two experienced florid hot flushes during the period of observation. However, all the subjects commented that although they would usually expect between S-10 flushes during the morning, the experimental conditions of the study considerably reduced the frequency of flushing. Thermography has provided some colourful objective evidence of acute skin temperature changes associated with the onset of a hot flush. Previous studies using conventional thermometers or thermocouples [3,4] have also reported temperature increases of between 0.5-2°C on the cheek though Molnar [4] found that there were increases of up to 5°C in the fingers and toes. However, the symptom of flushing is usually experienced mainly in the face, neck and upper trunk and it would seem that the subjective sensation of heat is out of proportion to the actual temperature increase, which was only about 1“C in these areas studied. Furthermore, the temperature increase often persisted for several minutes after the sensation of warmth had passed, indicating that the flush is only experienced while the skin temperature is increasing. The severity of the sensation is, therefore, probably related to the rate of change of temperature as well as the actual temperature increase. This study was part of a larger investigation of several aspects of the hot flush some of which have already been reported [5]. ACKNOWLEDGEMENTS
We are grateful to Syntex Pharmaceuticals us (D.W.S.) during this study.
Limited for the financial support of one of
REFERENCES [ l] Park, W.M. and Reece, B.L. (1976) l%mdamental aspects of medical thermography, Teaching Booklet No. 3, British Institute of Radiology, London. [2] Proceedings of 1st European Congress on Thermography, Amsterdam, 1974. Bibliotheca Radiologica, No. 6, Karger, Basei, 1975. [ 31 Collett, M.E. (1949) Basal metabolism at the menopause. J. Appl. Physiol. 1,629-636. (4) Molnar, G.W. (1975) Body temperature during menopausal hot flushes. J. Appl. Physiol. 38,499503. [S J Sturdee, D.W., Wilson, K., Pilipi, E. and Cracker, A.D. (1978) Physiological aspects of menopausal hot flush. Br. Med. J. 2,79-80.
