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PubMedDate not supplied

Role of the wireless thermologger system in the management of the autoclave unequipped with sensor ports.

Recently, the wireless thermologger system was developed. It consists of a wireless logger and the attached computer system. The wireless logger has a wireless structure and can be placed anywhere in the sterilizer chamber for thermometry. In the present study, thermal evaluations were performed twice using the wireless thermologger system in the sterilizer chamber of the prevacuum autoclave unequipped with sensor ports when it failed to pass the Bowie-Dick test and underwent mechanical repairs. Thermometry was performed when the Bowie-Dick test cycle was operated. The heat up time was measured in the range of 120.0-134.0 degrees C. The F0 value was calculated with the reference temperature at 121.0 degrees C and Z value at 10 degrees C when the sterilization temperature was over 120.0 degrees C. The first thermal evaluation was performed after three air-leaking points were repaired along with the replacement of the vacuum pump and the thermosensor. It revealed that the heat-up time was 4 min and 42 s and the F0 value was 137.5. After the temperature control systems were adjusted using the process calibrator in the prevacuum autoclave, the second thermal evaluation revealed that the heat up time was 2 mins 1 s and the F0 value was 102.7. The present study suggests that the wireless thermologger system is useful in the management of the autoclave unequipped with sensor ports when it undergoes mechanical repairs.

Electric Wiring↗
PubMed2004

Hyperthermia combined with radiation therapy in the treatment of local recurrent breast cancer.

BACKGROUND: Hyperthermia combined with radiation therapy was shown to be more effective in local recurrent breast cancer than radiotherapy alone, but its use is limited due to technical difficulties, stringent reimbursement policies and because it is time consuming. OBJECTIVES: To report our experience with a simple and convenient XRT + HT delivery system. METHODS: XRT was delivered through either electron or photon beams (total dose 30-40 Gy in previously irradiated fields or 50-70 Gy in non-irradiated fields). Hyperthermia was delivered by a dedicated HT device operating at 915 MHz. The heating session lasted 45 minutes. The maximal tumor surface temperature was set at 45 degrees C and modified according to patient comfort. No intratumoral (invasive) thermometry was used. At least two HT sessions were scheduled to each HT field during the entire XRT treatment period. Tumor response was evaluated every 3 months after completion of treatment. The overall survival was measured from XRT + HT initiation until the last follow-up. RESULTS: Fifteen women underwent 114 HT treatments delivered through 28 HT fields. Twenty-four HT fields (15 patients) were previously irradiated. There was complete infield response in 10 fields (6 patients), partial response in 8 fields (4 patients), no response or progressive disease in 4 fields (3 patients), and no parameters in 6 fields (5 patients). Eighteen fields (64%) had complete or partial response. Seven patients had outfield recurrence despite wide XRT + HT fields. Ulceration was the only major side effect (three patients, three fields). CONCLUSIONS: The combined HT+XRT delivery system, with no invasive thermometry, is a simple and effective method for treating local recurrent breast cancer.

Breast Neoplasms↗
PubMed2005

[Comparative aspects of the methods of diagnosis of soft tissue injuries in traumas of the talocrural articulation].

The authors give grounds for using effective methods of diagnosis of injuries of the talocrural articulation in clinical practice. The role of MRT, USI, thermometry are presented in a comparative aspect. The diagnostic means of traditional X-ray examinations are also shown. It was found that thermometry in complex with X ray methods of diagnosis and USI systematized the diagnostic information, allowed corrections of medical programs, determined the time of the end of restoration of injured elements of the talocrural articulation with special reference to each patient.

Adult↗
PubMed1990

[The graphic representation of the temperature field of the skin surface in the orbital area].

The paper describes results of researches on the possibility of graphic presentation of a temperature field of skin surface of the orbital area. A method of liquid crystal thermography and electron thermometry was used for examination of 30 patients with practically healthy eyes. It was shown that graphic presentation of data of liquid crystal thermography and electron thermometry remarkably facilitates documentation and analysis of the results obtained.

Electronics, Medical↗
PubMed1987

[Effect of peripheral thermoregulation on the results of various studies used in the diagnosis of the vibration syndrome].

The paper constitutes some attempt of evaluating the relationships between individual peripheral thermoregulation and results of tests routinely applied for diagnosing the vibration syndrome (cooling test, thermometry, palesthesiometry, capillaroscopy, isotopic capillary flow, thermography at rest). In a group of 126 clinically observed subjects with the suspected vibration syndrome, 3 subgroups of different peripheral thermoregulation have been singled out. Forty-seven subjects were classified as homoiothermics, thirty-one subjects as poikilothermics and forty-eight as-amphithermics. Statistically significantly more frequent were disturbances in the tests in poikilo- and amphithermics, as compared to homoiothermics. Analysis of particular tests demonstrated disturbed thermometry mostly in poikilothermics. The authors surmise that the less advantageous variant of individual peripheral thermoregulation (i.e. poikilo- and amphithermic) may promote a more rapid occurrence and development of the vascular form of the vibration syndrome.

Body Temperature Regulation↗
PubMed1984

Thermal dose expression in clinical hyperthermia and correlation with tumor response/control.

Thermal dose has been identified as one of the most important factors which influence the efficacy of hyperthermia. Adequate temperature must be delivered for an appropriate period of time to the entire tumor volume in order to achieve optimal therapeutic results. Present clinical thermometry systems provide coarse temperature readings, since only selected tumor or normal tissue temperatures are monitored. Experimental in vitro and in vivo data suggest that the minimal temperature observed in the tumor determines therapeutic effectiveness. Unfortunately, at the present time, clinical data documenting these observations are scarce. The inhomogeneity of temperature distribution throughout the tumor volume makes difficult accurate correlations with tumor response and subsequent tumor control. Several mathematical models have been offered to express the time-temperature equivalency in relation to a reference temperature (43 degrees equivalent). Factors such as step-down heating, fractionated hyperthermia, thermal adaptation, and combination with irradiation, in addition to physiological parameters such as blood flow, play a major role in the expression of thermal dose. In order to meaningfully express thermal dose in clinical hyperthermia, several procedures are recommended, such as static phantom studies of specific absorption rate distributions for heat delivery equipment, detailed thermal mapping in hyperthermia sessions, development of reliable predictive biomathematical models to express temperature-time equivalency, and the fostering of research in 3-dimensional noninvasive clinical thermometry.

Adenocarcinoma↗
PubMed1984

Will thermometric tomography become practical for hyperthermia treatment monitoring?

Thermal tomography refers to the acquisition of detailed thermal information throughout a slice of the subject. Experimental temperature information of this nature to be obtained experimentally using some form of scanning mechanism is usually implied by the term, noninvasive thermometry. Desirable specifications for such a system are presented, and the degree to which the proposed methods are likely to achieve these are reviewed. Four major issues that must be resolved for any system to be useful clinically are: (a) will the system interfere with coupling the heating source to the patient and will the physician or technologist have access as well; (b) will its noise rejection be sufficient to operate in the presence of strong electromagnetic or ultrasonic heating fields; (c) will the spatial, temporal, and thermal resolution be sufficient to record important variations during treatments; and (d) will the parameter sensed be a function only of temperature or will it change as a consequence of physiological variations or therapeutic effects? It is concluded that noninvasive temperature scanning is unlikely to have a significant effect on thermal therapy for many years. Conversely, invasive thermometry coupled with numerical modeling is well along the way to becoming clinically useful.

Body Temperature↗
PubMed1994

[The complex diagnosis of certain forms of uterine pathology after labor as the prevention of late puerperal complications].

Two groups of puerperae, group 1, n = 1000 and group 2, n = 860, were examined on days 3-4 and 5-6 after spontaneous delivery. Echography, hysteroscopy, bacteriological studies, local thermometry, measurements of the level of medium-sized molecules were used to diagnose postpartum endometritis and uterine subinvolution. In group 1 subinvolution of the uterus was diagnosed in 10.5% and postpartum endometritis in 4.8% of puerperae, in group 2 in 11 and 5.1% of examinees, respectively. In group 1 surgical treatment of the uterus was carried out in patients with uterine involution or postpartum endometritis, in group 2 such treatment was administered only to patients with postpartum endometritis on the basis of material substrate. Findings of local thermometry and levels of medium-sized molecules in patients with uterine subinvolution indicate a catabolic trend of metabolic processes. Surgical treatment of the uterus in subinvolution helped reduce the incidence of postpartum complications by 3.4 times.

Decidua↗
PubMed1977

[Thermometric investigations about the efficacy of beta-escin to reduce postoperative edema (author's transl)].

Beta-escin is highly effective in reducing postoperative edemas and swellings. It was tried to demonstrate the effect of beta-escin using the thermometry. The temperature of soft tissues and bones can be measured with the help of the thermometry, in this way the circulation of the skin can be determined. In 65 test persons so-called normal thermograms were established, using the infraredthermometer KT 41, which makes registrations without touching the skin. In 53 patients the temperature of the skin was checked after surgery of the hand. 27 patients received beta-escin (Reparil); 26 patients without medication served as controls. In every case the temperature of the operated hand was compared to the other hand. Among the patients, who received escin, the temperature of the operated hand rose for two days following surgery; afterwards it fell quickly. Among the controls the skin-temperature rose up to the 4. day after surgery and decreased slowly. These results demonstrate clearly that after using beta-escin there is a quick reduction of postoperative inflammation and edema.

Adult↗
PubMed1996

Phase I/II trial of combined 131I anti-CEA monoclonal antibody and hyperthermia in patients with advanced colorectal adenocarcinoma.

BACKGROUND: This pilot project was undertaken to evaluate the toxicity of and tumor response to combined 131I anti-carcinoembryonic antigen monoclonal antibody (131I anti-CEA RMoAb) and hyperthermia in patients with metastatic colorectal adenocarcinoma. METHODS: Nine patients who had colorectal carcinoma with liver metastases were enrolled in this study. Intact 131I anti-CEA RMoAb was used (the specific antibody was IMMU-4, provided by Immunomedics, Inc., Morris Plains, NJ). During the diagnostic phase, dosimetry revealed that the tumor site received a higher radiation dose than the surrounding normal tissues in only six patients. These six, who were treated with radioimmunotherapy and hyperthermia, were the basis of this study. The first three patients were treated with 30 mCi/m2 of 131I anti-CEA RMoAb, and the next three received 60 mCi/m2. Pharmacokinetic clearance data were reported for all nine patients. RESULTS: Thermometry data revealed an average T90 of 40.3 (+/- 1.4 degrees C) and T50 of 41.1 (+/- 1.2 degrees C). The average thermal dose equivalent at 42.5 degrees C was 34.5 (+/- 21.5) minutes. The average Tmin, Tmax, and Tmeam were 40 (+/- 1.2 degrees C), 42.4 (+/- 0.7 degrees C), and 41.1 (+/- 1.1 degrees C), respectively. The pharmacokinetic clearance data of antibody showed monoexponential plasma clearances in all patients except one, in whom a biexponential plasma clearance was observed. In general, similar plasma and whole-body clearances as well as similar urinary excretions were observed when diagnostic and therapeutic phases for each patient were compared. Two of the six patients showed a marked improvement in their symptoms; five patients showed a drop in carcinoembryonic antigen levels. A follow-up computed tomography scan one month after treatment showed no change in tumor volume in five patients; one patient showed a partial response. Three patients developed toxicity, two developed moderate thrombocytopenia (39,000 and 58,000), and the other patient developed hematoma resulting from the insertion of a catheter for thermometry. CONCLUSIONS: It is feasible to combine hyperthermia and radiolabeled monoclonal antibodies, and the combination was well tolerated by these patients. The interaction between hyperthermia and low dose rate radioimmunotherapy is complex. Further studies are necessary to explore the use of this combined modality in the management of maligancies.

Adult↗
PubMedDate not supplied

[Differential diagnosis of the level of traumatic damage of cervical spinal nerves and brachial plexus].

In 80 patients with paresis or paralysis of the upper extremity due to injury to the brachial plexus or cervical roots, EMG with muscular test, skin thermometry and radiculography were done. The comparison of EMG investigations and Lovett's test with the diagram of segmental and peripheral innervation gave only an approximate determination of the level and extent of injury. Skin thermometry demonstrated vasomotór disturbances in 330 patients. Vasodilating activity was present, in the first place, in patients with complete paralysis of the extremity. These cases showed no significant improvement after rehabilitation management. Radiculography permitted to determine exactly the number of damaged spinal nerve pouches and this damage was found in 16 out of 18 patients. The character and location of pain in the upper extremity were without any significant diagnostic value in relation to the site and degree of injury.

Brachial Plexus↗
PubMed1999

Vascular abnormalities in acute reflex sympathetic dystrophy (CRPS I): complete inhibition of sympathetic nerve activity with recovery.

BACKGROUND: Reflex sympathetic dystrophy/complex regional pain syndrome type I (RSD/CRPS I) is a painful neuropathic disorder that may develop as a disproportionate consequence of a trauma affecting the limbs without overt nerve injury. Clinical features are spontaneous pain, hyperalgesia, impairment of motor function, swelling, changes in sweating, and vascular abnormalities. OBJECTIVE: To investigate pathophysiological mechanisms of vascular abnormalities in RSD/CRPS I. DESIGN: Case study. SETTING: Autonomic test laboratory at a university hospital. PARTICIPANTS: A patient with an early stage of RSD/ CRPS I of the upper limb and 2 healthy control subjects. INTERVENTIONS: Cutaneous sympathetic vasoconstrictor innervation was assessed by measuring cutaneous blood flow (laser Doppler flowmetry) and skin temperature (infrared thermometry). To quantify sympathetic vasoconstrictor function, phasic (induced by deep inspiration) and tonic (induced by controlled thermoregulation) sympathetic reflexes were analyzed. Venous norepinephrine levels were determined bilaterally. The same tests were performed in the controls after induction of cutaneous antidromic vasodilation produced by histamine dihydrochloride application. MAIN OUTCOME MEASURE: Sympathetic cutaneous vasoconstrictor function in RSD/CRPS 1. RESULTS: Two weeks after the onset of RSD/CRPS I, skin temperature on the affected side was higher (close to core body temperature) than on the contralateral side at room temperature and during controlled thermoregulation, indicating maximal vasodilation. Phasic and tonic stimulation of cutaneous vasoconstrictor neurons did not induce a decrease of skin blood flow or temperature on the affected side but were normal on the contralateral side. Venous norepinephrine levels were lower on the affected side. Parallel to clinical improvement, loss of vasoconstrictor function completely recovered within weeks. Results of investigations in healthy subjects ruled out the possibility that antidromic vasodilation caused by activation of nociceptive afferents is responsible for the complete depression of sympathetic vasoconstrictor reflexes. CONCLUSIONS: Demonstrated for the first time is a complete functional loss of cutaneous sympathetic vasoconstrictor activity in an early stage of RSD/CRPS I with recovery. The origin of this autonomic dysfunction is in the central nervous system.

Autonomic Nervous System↗
PubMed1991

Microwave cyclodestruction for glaucoma in a rabbit model.

Microwave thermotherapy was used to treat experimentally induced glaucoma. Microwave-induced cyclodestruction was successful in reducing intraocular pressure in all treated glaucomatous eyes for 4 weeks. Two additional glaucomatous eyes were left untreated to serve as controls, and were noted to have persistently elevated intraocular pressures. Six additional eyes were then subjected to an equivalent treatment (50 degrees C in five 1-minute applications), which resulted in approximately 180 degrees of heat treatment just posterior to the corneoscleral limbus. These specimens were evaluated with light microscopy at baseline, 24 hours, and 7 days after treatment. Our clinical and histopathologic evaluations suggested that microwave thermotherapy (delivered under thermometry control) allowed for chorioretinal/ciliary body destruction that resulted in reductions of intraocular pressure in glaucomatous eyes.

Animals↗
PubMed1996

Tympanic temperature asymmetry and stress behavior in rhesus macaques and children.

OBJECTIVES: To examine left-to-right tympanic membrane temperature asymmetries and their possible association with biobehavioral stress responses in rhesus macaques and children. SUBJECTS AND DESIGN: Infrared tympanic membrane thermometry was completed bilaterally in 19 two-year-old rhesus macaques and 18 eight-year-old children in a cross-sectional, laboratory-based study. Unidirectional temperature gradients were calculated as the mean of two left-sided measurements minus the mean of two right-sided measurements. Biobehavioral stress responses were assessed in monkeys as agitated motor activity and adrenocortical activation after separation from the social group, and in children as parent-reported resilience to psychological stress and child behavior problems. RESULTS: Significant asymmetry was detected in tympanic membrane temperatures in both monkey and child samples, with left-sided temperatures measuring slightly but significantly higher than those from the right tympanic membrane. Higher-magnitude left-to-right temperature gradients were associated with stress-related locomotion in macaques and with lower resilience and more behavior problems in children. CONCLUSIONS: There are small but reliable asymmetries in the tympanic membrane temperatures of young human and nonhuman primates. Tympanic membrane temperature gradients reflect important individual differences in biologically derived responses to psychological stressors.

Adaptation, Psychological↗
PubMed1998

Feedback interstitial diode laser (805 nm) thermotherapy system: ex vivo evaluation and mathematical modeling with one and four-fibers.

BACKGROUND AND OBJECTIVE: In this study a newly developed microprocessor controlled power regulation and thermometry system integrated with a diode laser (805 nm wavelength) was evaluated with respect to temperature distribution, effectiveness of regulation, and ability to predict temperature distributions by computer simulation. STUDY DESIGN/MATERIALS AND METHODS: Experiments were performed in ground bovine muscle using either a single laser fiber or four-fibers. The target temperature at one (feedback) thermistor, placed 5 mm from one of the laser fibers, was set to 50 degrees C and was maintained by means of stepwise power regulation. The temperature distribution was monitored using multiple thermistor probes. A numerical model based on the bioheat equation was used to calculate the temperature distributions. RESULTS: Temperature regulation was excellent with a tendency towards better regulation in the four-fiber than in the single-fiber experiments. Agreement between calculated and measured temperatures was good. The coagulated (> 55 degrees C) and hyperthermic (> 45 degrees C) volumes were 6 and 10-11 times larger, respectively, with four-fibers than with a single fiber. CONCLUSION: It is concluded that the stepwise power regulation system was efficient in maintaining a stable target temperature. The results indicate that the system can produce lesion volumes adequate for treating a relatively large tumor in a single session and that computer simulation may be useful for predicting temperature distribution.

Animals↗
PubMed1999

MR-guided laser thermoablation of inoperable renal tumors in an open-configuration interventional MR scanner: preliminary clinical experience in three cases.

A minimally invasive technique for performing magnetic resonance (MR)-guided laser interstitial thermoablation (LITT) for inoperable renal tumors is described. Three patients were treated using a percutaneous technique with real-time MR guidance in an open access interventional MR scanner. Laser therapy was delivered using a neodymium-YAG source via a water-cooled applicator system. Thermal lesions were monitored in real time using a color thermometry sequence. All patients were discharged the following day with no complications. Follow-up with gadolinium-enhanced MRI in a conventional high-field system confirmed necrosis in targeted tissue, and further treatment is planned for one patient. We concluded that LITT can be useful in treating inoperable renal malignancy and merits further evaluation. J. Magn. Reson. Imaging 1999;10:545-549.

Aged↗
PubMed1999

Quantifying tissue damage due to focused ultrasound heating observed by MRI.

Focused ultrasound heating of ex vivo bovine kidney and liver was monitored using magnetic resonance imaging (MRI) to investigate the quantitative relationship between time-dependent temperature elevations and altered contrast in MR images due to thermal coagulation. Proton resonance frequency shift MR thermometry was performed during heating at 10 sec intervals (single-slice fast spoiled GRASS [FSPGR], theta/TE/TR 30 degrees/11/39 msec, field of view 8 cm, 256 x 256, 3 mm slice thickness, 1 NEX); post-heating MR images were T1-weighted (3D-FSPGR, theta/TE/TR 60 degrees/25/200 msec, 1 mm slice thickness, 3 NEX). Analysis of the resulting temperature versus time data using the Arrhenius relationship and a simple binary discrimination model showed that thermal coagulation occurred with heating at approximately 54 degrees C for 10 sec in both tissues and could be predicted with approximately 625 microm spatial resolution. These results suggest that quantitative MR guidance of thermal coagulation therapy is feasible, and they provide information useful for designing future investigations in vivo.

Animals↗
PubMed1999

Signal formation in echo-shifted sequences.

Echo shifted (ES) gradient-recalled echo sequences (whose TE > TR) have found important applications in fMRI and MR thermometry since their introduction. The technique increases T *(2) weighting in BOLD imaging and temperature change sensitivity in phase-based temperature imaging compared to FLASH sequences. Yet, inconsistent observations have previously been reported when variants of this technique were used in various MRI experiments. Previous understanding of the ES sequences (the "FLASH-like" postulation) was not sufficient to explain these observations. This work provides an in-depth study on the various ES sequences. It was found that there are two types of ES sequences: ES-FLASH that spoils coherent transverse magnetization and ES-GRE, which is based on SSFP signals. A signal expression was derived for the clinically popular TR-periodic ES-GRE sequence with one echo shift. This signal expression reduced to the "FLASH-like" postulation under certain conditions. The new knowledge about the echo formation mechanism in ES sequences helps explain the experimental observations previously reported. Moreover, the resonance offset angle based analysis demonstrates an elegant methodology to analyze short TR imaging sequences. Magn Reson Med 42:864-875, 1999.

Brain↗