First application of dynamic infrared imaging in boron neutron capture therapy for cutaneous malignant melanoma.

First application of dynamic infrared imaging in boron neutron capture therapy for cutaneous malignant melanoma.

Santa Cruz GA, González SJ, Bertotti J, Marín J.

Source

Departamento de Instrumentación y Control, Comisión Nacional de Energía Atómica, Avenida del Libertador 8250, 1429 Buenos Aires, Argentina. santacr@cnea.gov.ar

Abstract

PURPOSE:

The purpose of this study is to assess the potential of dynamic infrared imaging (DIRI) as a functional, noninvasive technique for evaluating the skin acute toxicity and tumor control within the framework of the Argentine boron neutron capture therapy (BNCT) program for cutaneous malignant melanoma.

METHODS:

Two patients enrolled in the Argentine phase I/II BNCT clinical trial for cutaneous malignant melanoma were studied with DIRI. An uncooled infrared camera, providing a video output signal, was employed to register the temperature evolution of the normal skin and tumor regions in patients subjected to a mild local cooling (cold stimulus). In order to study the spatial correlation between dose and acute skin reactions, three-dimensional representations of the superficial dose delivered to skin were constructed and cameralike projections of the dose distribution were coregistered with visible and infrared images.

RESULTS:

The main erythematous reaction was observed clinically between the second and fifth week post-BNCT. Concurrently, with its clinical onset, a reactive increase above the basal skin temperature was observed with DIRI in the third week post-BNCT within regions that received therapeutic doses. Melanoma nodules appeared as highly localized hyperthermic regions. 2 min after stimulus, these regions reached a temperature plateau and increased in size. Temperature differences with respect to normal skin up to 10 degrees C were observed in the larger nodules.

CONCLUSIONS:

Preliminary results suggest that DIRI, enhanced by the application of cold stimuli, may provide useful functional information associated with the metabolism and vasculature of tumors and inflammatory processes related to radiation-induced changes in the skin as well. These capabilities are aimed at complementing the clinical observations and standard imaging techniques, such as CT and Doppler ultrasound.

Analysis of transient thermal images to distinguish melanoma from dysplastic nevi

Analysis of transient thermal images to distinguish melanoma from dysplastic nevi

Muge Pirtini Çetingül ; Hasan E. Çetingül ; Cila Herman

Abstract

We have recently developed a dynamic infrared (IR) imaging system that provides accurate measurements of transient thermal response of the skin surface for characterizing lesions. Our hypothesis was that malignant pigmented lesions with increased proliferative potential generate quantifiable amounts of heat and possess an ability to reheat more quickly than the surrounding normal skin, thereby creating a marker of melanoma lesions vs. non-proliferative nevi. In our previous studies, we demonstrated that the visualization and measurement of the transient thermal response of the skin to a cooling excitation can aid the identification of skin lesions of different origin. This capability of distinguishing benign from malignant pigmented lesions is expected to improve the specificity and sensitivity for melanoma as well as other skin cancers, while decreasing the number of unnecessary biopsies. In this work, in order to quantify the transient thermal response with high accuracy, we present a processing framework on multimodal images, which includes a feature point (landmark) detection module, an IR image registration module that uses the resulting landmarks to correct involuntary body/limb motion and an interactive white-light image segmentation module to delineate the contours of the lesions. The proposed method is tested in a pilot patient study in which all the patients possess a pigmented lesion with a clinical indication for biopsy. After scanning, biopsying, and grading the lesions for malignant potential, we observe that the results of our approach match well with the biopsy results.

A Novel Method of Measuring Tear Evaporation Rates using Infrared Thermography

A Novel Method of Measuring Tear Evaporation Rates using Infrared Thermography

Andrea Petznick¹, Samantha Sze Yee Lee¹, Jen Hong Tan², U. Rajendra Acharya^2,3,4, Eddie Ng⁵, Louis Tong^1,6,7,8

¹Singapore Eye Research Institute, Singapore

²School of Engineering, Ngee Ann Polytechnic, Singapore

³SIM University, Singapore

⁴Singapore Institute of Technology – University of Glasgow, Singapore

⁵School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore

⁶National Eye Centre, Singapore

⁷Duke-NUS Graduate Medical School, Singapore

⁸Yoon Loo Lin School of Medicine, National University of Singapore

PURPOSE: Dry eye is a very common medical problem and meibomian gland dysfunction (MGD) may be an aggravating factor. There is no single reliable diagnostic tool to determine the presence and severity of dry eye and MGD. The measurement of dynamic tear evaporation rates would allow for a more objective diagnosis. In this study, we present a novel non-invasive method of measuring tear evaporation rates using infrared thermography that is reliable and able to detect changes after heat therapy.

METHODS: Infrared thermographic sequential images of ocular surface temperature were recorded from healthy participants (mean age ± SD: 24±7 years) while remaining in a consulting room with a temperature of 22.08±0.77°C and humidity of 63.82±0.02%. 1) Repeatability of the equipment was tested by taking 2 measurements 20 min apart (n=16). 2) Measurements were taken before and 60 min after 5-min heated eye mask wear (Eyegiene^®, US) (n=10) to test for changes in ocular surface temperature and tear evaporation. Tear evaporation rates were calculated based on ocular surface temperature profiles and controlled for body and room temperature as well as room humidity using principles of thermodynamics. Statistical comparisons were performed using paired t-test with p<0.05.

RESULTS: 1) There were significant correlations between the first and second measurements of ocular surface temperature (r=0.94) and tear evaporation rates (r=0.98) (p<0.01). The coefficients of repeatability were 0.42˚C for ocular surface temperature and 6.78 Wm^-2 for tear evaporation rates. 2) Ocular surface temperature before heat therapy was 33.66±0.53˚C which significantly decreased to 32.50±0.97˚C after heat application (p<0.01). Tear evaporation rates significantly increased from 65.64±12.51 to 78.72±21.53 Wm^-2 following heat treatment (p<0.01). 

CONCLUSIONS: We established that ocular thermography has a good repeatability in measuring ocular surface temperatures and tear evaporation rates under constant conditions and may therefore present a valuable tool for diagnosing dry eye and MGD. Findings also suggest a drop in ocular surface temperature and an increase in tear evaporation 60 min after heating, but it is possible that vasodilation in ocular tissues may have affected calculations of tear evaporation rates after heating.

Impacts on the skin temperature by the different distances of moxibustion: discussion on the safe distance of moxibusiton.

Impacts on the skin temperature by the different distances of moxibustion: discussion on the safe distance of moxibusiton.
Xu PC, Lee TL, Cui SL.

Source Acupuncture Clinic, Rehabilitation Centre of National University Hospital, Singapore 119074, Singapore. pecxu@163.com

Abstract
OBJECTIVE: To observe the impacts of the different distances of moxibustion on local skin temperature and provide a safy distance of moxibustion.

METHODS: Three healthy adult volunteers were included. The pure moxa stick (without other herbs mixed together) was used. The moxa-stick moxibustion and the mild moxibustion (with moxa box) were applied to Zusanli (ST 36) on the right side and Guanyuan (CV 4) respectively. The distance from moxibustion to the local skin was 2 cm, 3 cm and 4 cm separately. The moxibustion time was limited by 3 cm stick burned out. The infrared thermography was adopted to record and store thermal images and made the systematic analysis. The same trial was repeated on the second day. The means of the skin temperature measured at each acupoint each time was taken as the results for the analysis.

RESULTS: (1) Moxibustion with moxa box at Guanyuan (CV 4): at the distance of 4 cm, the local skin temperature at over 44 degrees C [(44.1 +/- 1.3)-(46.7 +/- 1.5) degrees C)] lasted 7 min; at the distance of 3 cm, the local skin temperature at over 44 degrees C [(44.1 +/- 1.3)-(49.3 +/- 2.0) degrees C] lasted about 10 min and that at over 49 degrees C [(49.0 +/- 2.1)-(49.3 +/- 2.0) degrees C)] lasted 2 min; at the distance of 2 cm, the observation could not be followed due to local burning pain. (2) Moxa-stick moxibustion at Zusanli (ST 36): at the distance of 4 cm, the skin temperature was ranged from (40.0 +/- 2.0) degrees C to (44.9 +/- 2.3) degrees C; at the distance of 3 cm, in 1 min of moxibustion, the skin temperature increased over 44 degrees C, sustaining in the range from (45.9 +/- 3.0) degrees C to (47.8 +/- 2.0) degrees C; at the distance of 2 cm, the observation could not be followed due to local burning pain.

CONCLUSION: In moxibustion, the closer the moxa stick to the skin is, the higher the local skin temperature is. No matter with stick moxibustion or box moxibustion, the distance of moxa stick to the skin should be in the range from 3 to 4 cm.

Peripheral facial paralysis aided by infrared thermography.

Peripheral facial paralysis aided by infrared thermography.
We have carried out clinical observations on 34 patients with peripheral facial paralysis treated by
acupuncture therapy prescribed according to selection of treatment regimen on the basis of facial
thermogram and temperature. A comparison was made with a control group of 97 patients who received conventional acupuncture therapy only. It was found that: (1) The cure rate in the group of selecting acupoints by thermogram (hereinafter referred to as the thermography--aided treatment group) was 67.65%, with a marked improvement rate of 26.40%; while the cure rate of the conventional acupuncture treatment group (hereinafter called the conventional treatment group) was 46.39%, the marked improvement rate being 29.90%, indicating a significant difference in therapeutic efficacy between the two groups (P less than 0.02). (2) The average duration of acupuncture therapy for the thermography aided treatment group was 6.02 weeks, whereas that for the conventional treatment group, 24 weeks. There was also a significant difference between the two groups (p less than 0.01). (3) During the entire therapeutic course, 25.2 sessions of treatment were given on the average in the thermography--aided treatment group, and 78.8 sessions in the conventional treatment group, showing a very significant difference (P less than 0.001). The present thermography--aided method exhibits advantages over the conventional one in enhancing the cure rate and shortening the duration of treatment, which is worthy to be popularized in clinical practice. It is also of certain significance in standardization and scientification of acupuncture therapy.
Zhang D; Wei Z; Wen B; Gao H; Peng Y; Wang F.

Facial thermography is a sensitive and specific method for assessing food challenge outcome.

Facial thermography is a sensitive and specific method for assessing food challenge outcome.
Clark AT, Mangat JS, Tay SS, King Y, Monk CJ, White PA, Ewan PW.
Department of Allergy, Cambridge University Hospitals NHS Trust, Addenbrookes Hospital, Cambridge, UK.

BACKGROUND: Oral challenge is widely used for diagnosing food allergy but variable interpretation of subjective symptoms may cause error. Facial thermography was evaluated as a novel, objective and sensitive indicator of challenge outcome.

METHODS: A total of 24 children with a history of egg allergy underwent oral challenge, which were scored positive when objective symptoms occurred or negative after all doses were consumed without reaction. Facial temperatures were recorded at baseline and 10-min intervals. The difference between mean and baseline temperature (DeltaT), maximum DeltaT during challenge (DeltaT(max)) and area under curve of DeltaT against time (DeltaTAUC) were calculated for predefined nasal, oral and forehead areas, and related to objective challenge outcome.

RESULTS: There were 13 positive and 11 negative challenges. Median nasal DeltaTAUC and DeltaT(max) were greater in positive compared with negative challenges (231- and 5-fold, respectively; P < 0.05). In positive challenges, nasal temperatures showed an early transient rise at 20 min, preceding objective symptoms at median 67 min. There was a sustained temperature increase from 60 min, which was reduced by antihistamines. A cut-off for nasal DeltaT(max) of 0.8 degrees C occurring within 20 min of the start of the challenge predicted outcome with 91% sensitivity (positive predictive value [PPV] 100%) and 100% specificity (negative predictive value [NPV] 93%). Subjective symptoms occurred in four of 13 positive and three of 11 negative challenges.

CONCLUSIONS: Facial thermography consistently detects a significant early rise in nasal temperature during positive compared with negative food challenges, which is evident before objective symptoms occur. Thermography may therefore provide a sensitive method to determine outcome of food challenges and investigate the pathophysiology of food allergic reactions.