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PubMed2003

Evidence of hemispheric specialization in marmosets (Callithrix penicillata) using tympanic membrane thermometry.

Recent studies have employed tympanic thermometry to assess lateralization of cognitive and emotional functions in primates. However, no studies using this technique have investigated the possibility of hemispheric specialization in New World monkeys. Therefore, the aim of the present study was to investigate tympanic membrane (TM) temperature asymmetries and their possible correlation with stress responses in marmosets (Callithrix penicillata). Infrared TM thermometry was completed bilaterally in 24 animals (14 males and 10 females) during a stressful situation of capture and restraint. There were no significant differences between gender. A significant negative correlation was observed between TM temperature of the right ear and the number of captures (r = -0.633; P<0.001). Subjects with a more frequent previous history of captures (5 to 9 captures; N = 11) showed lower TM temperature when compared to those with fewer previous captures (1 to 4 captures; N = 13). No differences were observed for the left TM temperature. These results suggest that under intense emotional challenge (capture and restraint) there is a stronger activation of the neural structures situated in the right brain hemisphere. Taken together, the data reveal for the first time evidence of hemispheric specialization in emotional physiological processing in a New World monkey.

Animals↗
PubMed1991

Tympanic thermometry: an index of hemispheric activity.

This article describes the use of tympanic thermometry in investigations of hemispheric specialization. Subjects were asked to perform tasks known to be performed preferentially by the right or left hemisphere while fluctuations in tympanic temperature (reflecting changes in hemispheric metabolic activity) were recorded from thermal sensors placed in their outer ear canals. The analyses show that subjects who evince relatively higher elevations in metabolic activity (as measured through tympanic thermometry) in the hemisphere specialized for the task obtain better performance scores than those who show a reversed bias.

Adolescent↗
PubMedDate not supplied

Perturbations due to the use of catheters with non-perturbing thermometry probes.

Perturbations due to the use of catheters with non-perturbing thermometry probes were investigated in static phantom at 915 MHz. Fibre optic probes for the Luxtron and Clini-Therm thermometry systems, and Vitek probes for the BSD hyperthermia systems, were inserted in closed-end catheters at depths up to 2 cm in the phantom and exposed parallel to the E-field. The probes alone produced 0-12 per cent changes in heating and catheters alone were 0-20 per cent. When the probes were inserted in catheters, perturbations were 0-12 per cent at the surface and 1 cm depth, and 5-15 per cent at 2 cm depth. Even with non-perturbing probes it is important to place catheters perpendicular to the E-field during microwave hyperthermia.

Electromagnetic Fields↗
PubMedDate not supplied

Non-invasive MR thermometry by 2D spectroscopic imaging of the Pr[MOE-DO3A] complex.

Future progress in regional hyperthermia requires a practical method for non-invasive thermometry. In magnetic resonance tomography, spin density, T1 relaxation time, diffusion coefficient and proton resonance frequency are candidates to measure temperature distributions. When used clinically in the pelvic region, all these methods are compromized by artifacts arising from different tissues, tissue alterations under hyperthermia, physiological and random movements, inhomogeneities, drift phenomena, and field instabilities. In this study a paramagnetic complex was evaluated, Pr[MOE-DO3A], with praseodymium as central atom, similar to common gadolinium containing MRI contrast media. The temperature dependence of its methoxy side group approximately -24 ppm downfield from the water resonance at 25 degrees C was employed to determine 2-D temperature distributions in a cylindrical agar phantom containing 9.5 mM of Pr[MOE-DO3A]. The phantom was heated externally through a water jacket creating a stationary temperature distribution throughout the phantom. At first, the correlation between temperature and the chemical shift of the methyl group of the lanthanide complex Pr[MOE-DO3A] was determined. Calibration curves obtained exhibited a linear relationship of 0.12 +/- 0.01 ppm/degree C, nearly independent from the surrounding medium. Local temperature distributions were determined employing the spatially resolved method of spectroscopic imaging (SI). 2-D spectroscopic images for three orthogonal slices were obtained by narrow-band excitation and 16 phase encoding steps in two dimensions. The FOV was 180 mm and the slice thickness in all cases was 20 mm for maximal spatial temperature resolution (11.2 x 11.2 mm2). The results indicate a measurement time of about 5s per acquisition under the following conditions: An estimated concentration of 1 mmol/l, a reduced matrix size of 8 x 8, and a reduced repetition time of 3 x T1 (TR approximately 85 ms). Those SI measurements produced a SNR of approximately 4 per acquisition, a measurements duration of 10-20 s, equivalent to two to four acquisitions per spectrum, seem sufficient for online temperature monitoring during hyperthermia. The in vitro data suggest the spectroscopic temperature measurement utilizing a temperature-sensitive Pr[MOE-DO3A] complex with a therapeutically realistic concentration of 1 mmol/l to be suitable for clinical use. Compared to the methods tested so far (rho, T1, diffusion, proton resonance), the method presented has the unique advantage of being less susceptible to artifacts. The competing methods of non-invasive thermometry employing magnetic resonance imaging are currently being investigated using the same experimental setup.

Hyperthermia, Induced↗
PubMed2002

Comparison of rectal and tympanic thermometry during exercise.

BACKGROUND: Heat-related deaths are among the most preventable injuries in athletics. We sought to examine two methods of monitoring body temperature during exercise as a means of preventing heat-related illnesses. METHODS: Ten adult subjects exercised in hot, humid conditions while body temperature was monitored by rectal (Tre) and tympanic (Tty) thermometry. RESULTS: Our results indicate that increase in Tty was significantly greater than increase in Tre during exercise. However, rectal temperatures continued to increase after exercise cessation and peak temperatures were not significantly different. Temperature readings of the two devices during exercise had a strong correlation. There was a poor correlation between the two methods of measurement in the recovery phase. CONCLUSIONS: Tympanic thermometry is reliable for monitoring changes in body temperature during exercise. This could be valuable for monitoring individuals during long exercise in an effort to prevent heat exhaustion or heat stoke.

Adult↗
PubMed2003

[Infrared temporal thermometry].

BACKGROUND: Thermometry at other body sites than the rectum may have its advantages. Some studies have shown that infrared tympanic measurement has poor sensitivity in febrile patients. We evaluated a new infrared temporal thermometer that calculates core temperature by measuring skin temperature and ambient temperature over the superficial temporal artery. MATERIAL AND METHODS: During two periods in 2002, 164 consecutive intensive care patients were measured by both digital rectal and infrared temporal thermometry. RESULTS: The average difference between rectal and temporal measurements was 0.3 degrees C. Fever was defined as a rectal temperature of 38 degrees C and was present in 70 patients. The temporal scanner detected fever in 33 of those patients, which gives a sensitivity of 53 % (95% CI 41-65%) and a specificity of 96 % (95% CI 90-99%). The positive predictive value was 90% (95% CI 77-97%) and the negative predictive value 73% (95% CI 64-81%). INTERPRETATION: The results are better than for infrared tympanometry. The sensitivity of the infrared temporal thermometer for detecting rectally measured fever is too low to recommend its use in adult intensive care patients.

Adult↗
PubMed1992

The clinical use of thermocouple thermometry.

The development of a clinical thermometry system entails solving both clinical and technical problems. A thermometry system will, in general, be comprised of a temperature transducing element, a mechanism for interrogating the transducer temperature, and a means of interpreting, reporting and recording the measured temperature. Thermocouples are thermometers which report their own temperature, while the parameter of interest is the temperature of the medium. The two key questions which arise are then: (1) is the thermometer correctly reporting its own temperature, and (2) what is the relationship between the medium temperature and the thermometer temperature? In this work some of the important parameters influencing the temperature of the thermometer and the thermal relationship between the thermometer and the medium are investigated.

Body Temperature↗
PubMedDate not supplied

[The specificity of thermometry of cadavers of newborns in prescribing the time of the coming of death].

It is distinctly demonstrated on the basis of 7908 measurements of rectal temperature of cadavers of newborns that such thermometry should be made at a depth of at least 5.5 cm in order to ensure an accurate prescription of the coming of death (PCD) in expertise of cadavers of newborns. An optimal method of calculating the sought results as applicable to different situations and made with the help of correction factors is described. The results of lifetime thermometry of 60 newborns are presented, which prove that the length of intrauterine life of a baby affects essentially its values. An accurate PCD of a newborn is a technical study result.

Body Temperature↗
PubMed2002

[Design of double ultrasound pulse transmitting and receiving circuits used in ultrasound thermometry].

This paper introduces double ultrasound pulse transmitting and receiving circuits used in ultrasound thermometry. Using the circuits, double ultrasound pulses could be made synchronously to satisfy the requirements of ultrasound thermometry, and the weak ultrasound echo signals are received successfully. The crux experiment waveform offered shows that the circuits have high reliability.

Equipment Design↗
PubMed2006

Comparison of rectal, microchip transponder, and infrared thermometry techniques for obtaining body temperature in the laboratory rabbit (Oryctolagus cuniculus).

This study compared rabbit rectal thermometry with 4 other thermometry techniques: an implantable microchip temperature transponder, an environmental noncontact infrared thermometer, a tympanic infrared thermometer designed for use on humans, and a tympanic infrared thermometer designed for use on animals. The microchip transponder was implanted between the shoulder blades; the environmental noncontact infrared thermometer recorded results from the base of the right pinna and the left inner thigh, and the tympanic infrared thermometer temperatures were taken from the right ear. Results from each technique were compared to determine agreement between the test modality and the rectal temperature. The practicality and reliability of the modalities were reviewed also. According to this study, the implantable microchip transponder measurements agreed most closely with the rectal temperature.

Animals↗
PubMed1990

[Computer-assisted infrared thermometry in orthopedics].

Computer-assisted Infrared Thermometry in Orthopaedics. Infrared Thermometry is a relative new non-invasive medico examination technic. The short period of the measured heat of the body surface demanded a special surveying equipment. That's why in the Consultant Orthopaedic Hospital Bad Düben a computer-assisted measuring system was developed. By using this system we have good experience in the postoperative control of wound healing, in the judgement of stress-fracture and in the rheumatic-orthopaedics.

Computers↗
PubMed1994

[Computerized digital thermometry in acrosyndromes. Personal experience].

A diminution of the cutaneous temperature of the fingers and the latter's delayed recovery are constant features in the symptomatological triad of Raynaud's disease (RD). Thermometry is a method which can provide an objective evaluation of this phenomenon. The authors aimed to verify the value of thermometry using a computerised digital thermometer to measure basal temperature, that during cooling to 10 C, and the response. A computerised system with an AVTR interface was utilized using different probes for the 10 fingers and measuring temperature minute by minute up to 25 degrees. A total of 51 subjects were examined: 19 were asymptomatic for acrolocalised pathologies and 32 were symptomatic. No close correlation was observed between clinical and instrumental data. In fact 31.5% of the asymptomatic subjects had a "non-normal" reaction to the test; on the other hand, in the group of female over-50-years-old with symptoms suggesting RD, 44.4% of cases revealed normal instrumental patterns. Therefore no discriminating parameters were identified which might have allowed the instrumental identification of subjects suffering from RD compared to healthy individuals: there was a good level of sensitivity but scarce specificity.

Adult↗
PubMed1993

[Relative accuracy and precision of two non-invasive thermometry systems].

The relative accuracy and precision of the two non-invasive thermometry systems, FirstTemp (Intelligent Medical Systems, USA), an infrared tympanic thermometer, and CTM-205 (Terumo, Japan), a newly developed deep body thermometry system, were evaluated in 32 patients undergoing various surgeries under general anesthesia using esophageal temperature as the reference value. The "limits of agreement (mean difference +/- 2SD)" of the "core" temperature measured by FirstTemp and esophageal temperature was 0.4 +/- 0.5 degrees C, and was larger (P < 0.01) than those between rectal temperature and esophageal temperature (0.2 +/- 0.7 degrees C), between tympanic membrane temperature and esophageal temperature (-0.1 +/- 0.4 degrees C), and between "forehead deep body temperature" measured by CTM-205 and esophageal temperature (-0.2 +/- 0.7 degrees C). The "limits of agreement" between "forehead deep body temperature" and esophageal temperature did not differ from that between tympanic membrane temperature and esophageal temperature. The repeatability of the measurement by FirstTemp was good; the difference between paired measurement values was 0 +/- 0.2 degrees C (mean +/- 2SD). We conclude that the relative accuracy and precision of the two systems are still not sufficient for monitoring body temperature during general anesthesia.

Aged↗
PubMed1996

Infrared thermometry for rapid, noninvasive detection of reflux of spermatic vein in varicocele.

PURPOSE: We evaluated infrared thermometry for measurement of reflux of blood via the internal spermatic vein. MATERIALS AND METHODS: The change in scrotal temperature in patients with varicoceles and controls with different positions was measured with an infrared thermometer. RESULTS: Scrotal neck temperature in the patients increased during Valsalva's maneuver with upright position (mean plus or minus standard deviation 34.62 +/- 1.20 to 36.05 +/- 1.42C), while no statistically significant increase occurred in the controls (32.91 +/- 0.92 to 33.42 +/- 1.15C). Two weeks after high ligation of the internal spermatic vein the scrotal temperature in the patients decreased to the same level (0.59 +/- 0.84C) as in the controls. Using this method 2 subclinical varicoceles were also found on the right side in patients with a left varicocele. CONCLUSIONS: Infrared thermometry is noninvasive, rapid and simple for documenting varicoceles, including subclinical disease.

Adult↗
PubMed1997

[Clinical thermometry. I. Historical developments].

Determination of human core temperature has a long history. Since Antiquity, the significance of normal and abnormal body temperatures has been the subject of various interpretations. In this respect, theories based on humoral pathology were replaced by more scientific concepts in the 19th and 20th centuries. Objective measurement and comparison could be performed only after the invention of the thermometer and the introduction of temperature scales. Sanctorius and subsequently Boerhaave and others emphasized the use of measurement of body temperature in the clinic, but its importance was not accepted generally until the late 19th century. Many physicians and scientists have contributed to the progress of thermometry; however, the creation of a firmer scientific basis for clinical thermometry is usually attributed to Wunderlich.

Body Temperature↗
PubMedDate not supplied

[Chrono-thermometry in the diagnosis of Raynaud-like vasculopathies caused by prolonged use of vibrating tools].

Raynaud's phenomenon may be secondary to several different pathological conditions. In some cases it is favoured by occupational exposure to vibration of the upper arms. The diagnosis of Raynaud's phenomenon requires clinical information together with specific technical investigations. This report presents the results of 232 chrono-thermometric tests performed on 157 workers exposed to vibrations during the use of different kinds of tools. Seventy-five subjects not exposed to vibrations of the upper arms but with suspected Raynaud's syndrome were also tested. Chrono-thermometry enabled us to distinguish between three different subgroups of subjects exposed to vibrations: 61 workers with "normal" chrono-thermometry, 33 subjects with "pathological" vascular reactivity to cold in some fingers and 63 workers with such reactivity in all fingers. Similarly the 75 patients not exposed to vibration could also be divided into three groups. No statistical difference was found between the chrono-thermometric results obtained from the exposed and non-exposed subjects when divided into the three subgroups. The overall analysis of the combined results of the different kinds of tests (capillaroscopy plus a vascular reactivity test) is discussed.

Adolescent↗
PubMed2001

Influence of minor ear surgery on infrared tympanic thermometry.

BACKGROUND: Infrared tympanic thermometry (ITT) is often used for postoperative recovery room monitoring regardless of recent minor otologic surgery. OBJECTIVE: To evaluate the use of ITT in pediatric patients who have undergone bilateral myringotomy with insertion of pressure-equalizing tubes. DESIGN: A prospective cohort study. SETTING: Tertiary care academic medical center. PATIENTS: Consecutive patients of a staff pediatric otolaryngologist (M.A.R.): (1) ear surgery group, children aged 10 years or younger undergoing bilateral myringotomy with insertion of pressure-equalizing tubes and (2) non-ear surgery group, children aged 10 years or younger undergoing bilateral tonsillectomy with or without adenoidectomy. INTERVENTIONS: Immediate preprocedure temperature measurements included right and left ear ITT. Immediate postprocedure temperature measurements included right and left ear ITT and thermistor probe rectal temperature. MAIN OUTCOME MEASURES: The average difference between the preprocedure and postprocedure tympanic temperature in the ear surgery group was compared with that in the non-ear surgery group. The average difference between postprocedure rectal and ear temperature in the ear surgery group was compared with that in the non-ear surgery group. RESULTS: There were 20 patients (40 ears) in the ear surgery group and 20 patients (40 ears) in the non-ear surgery group. In the ear surgery group, the average difference between the preprocedure and postprocedure tympanic temperature (0.55 degrees C) was not significantly different from that (0.62 degrees C) in the non-ear surgery group (P =.66, 1-way analysis of variance). In the ear surgery group, the average difference between postprocedural rectal and ear temperature (1.94 degrees C) was not significantly different from that (1.89 degrees C) in the non-ear surgery group (P =.76, 1-way analysis of variance). CONCLUSION: Recent minor ear surgery (bilateral myringotomy with insertion of pressure-equalizing tubes) does not have a significant effect on ITT measurements in pediatric patients.

Adenoidectomy↗
PubMed1999

Heat-source orientation and geometry dependence in proton-resonance frequency shift magnetic resonance thermometry.

The proton-resonance frequency (PRF) shift method of thermometry has become a promising tool for magnetic resonance image-guided thermal therapies. Although the PRF thermal coefficient has recently been shown to be independent of tissue type when measured ex vivo, significant discrepancy remains on its value for tissues measured in vivo under a variety of experimental conditions. The authors identify a potential source of variation in the PRF thermal coefficient that arises from temperature-induced changes in the volume magnetic susceptibility of tissue and is dependent on the orientation and geometry of the heat-delivery device and its associated heat pattern. This study demonstrates that spatial variations in the apparent PRF thermal coefficient could lead to errors of up to +/-30% in the magnetic resonance estimated temperature change if this effect is ignored.

Algorithms↗