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.

Vision of the future: initial experience with intraoperative real-time high-resolution dynamic infrared imaging

Vision of the future: initial experience with intraoperative real-time high-resolution dynamic infrared imaging.
Technical note.
Ecker RD, Goerss SJ, Meyer FB, Cohen-Gadol AA, Britton JW, Levine JA. Department of Neurological Surgery, Mayo Clinic and Foundation, Rochester, Minnesota, USA.

High-resolution dynamic infrared (DIR) imaging provides intraoperative real-time physiological,
anatomical, and pathological information; however, DIR imaging has rarely been used in neurosurgical patients. The authors report on their initial experience with intraoperative DIR imaging in 30 such patients. A novel, long-wave (8-10 micron), narrow-band, focal-plane-array infrared photodetector was incorporated into a camera system with a temperature resolution of 0.006 degrees C, providing 65,000 pixels/frame at a data acquisition rate of 200 frames/second. Intraoperative imaging of patients was performed before and after surgery. Infrared data were subsequently analyzed by examining absolute differences in cortical temperatures, changes in temperature over time, and infrared intensities at varying physiological frequencies. Dynamic infrared imaging was applied in a variety of neurosurgical cases. After resection of an arteriovenous malformation, there was postoperative hyperperfusion of the surrounding brain parenchyma, which was consistent with a loss of autoregulation. Bypass patency and increased perfusion of adjacent brain were documented during two of three extracranial-intracranial bypasses. In seven of nine patients with epilepsy the results of DIR imaging corresponded to seizure foci that had been electrocorticographically mapped preoperatively. Dynamic infrared imaging demonstrated the functional cortex in four of nine patients undergoing awake resection and cortical stimulation. Finally, DIR imaging exhibited the distinct thermal footprints of 14 of 16 brain tumors. Dynamic infrared imaging may prove to be a powerful adjunctive intraoperative diagnostic tool in the neurosurgical imaging armamentarium. Real-time assessment of cerebral vessel patency and cerebral perfusion are the most direct applications of this technology. Uses of this imaging modality in the localization of epileptic foci, identification of functional cortex during awake craniotomy, and determination of tumor border and intraoperative brain shift are avenues of inquiry that require further investigation.