Fast Joule-Thomson Cryocycling Device for Cryosurgical Applications

Maytal, Ben-Zion

doi:10.1007/978-1-4757-9047-4_114

Cited by 15 publications

(6 citation statements)

References 1 publication

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“…Next, according to the prostate geometry and suspected or known location of the lesion, the surgeon inserts transperineally 5-7 cryoprobes, each 1.5-3 mm in diameter, while monitoring cryoprobe positioning with the ultrasound. In the third generation of cryotherapy systems, which is currently employed in clinical practice, pressurized argon gas is cooled below −100 °C inside the cryoprobes via Joule-Thomson effect, freezing tissues surrounding the exposed tip of a cryoprobe within seconds (Maytal 1998). The cryoprobes are set at a safe distance (not less than 5 mm) from the vulnerable structures of the urethra and rectal wall, and the lengths of their freezing tips are adjusted to cover precisely the treated area only.…”

Section: In Vivo Optoacoustic Temperature Imaging For Image-guided Cr...mentioning

confidence: 99%

In vivooptoacoustic temperature imaging for image-guided cryotherapy of prostate cancer

et al. 2018

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The objective of this study is to demonstrate in vivo the feasibility of optoacoustic temperature imaging during cryotherapy of prostate cancer. We developed a preclinical prototype optoacoustic temperature imager that included pulsed optical excitation at a wavelength of 805 nm, a modified clinical transrectal ultrasound probe, a parallel data acquisition system, image processing and visualization software. Cryotherapy of a canine prostate was performed in vivo using a commercial clinical system, Cryocare CS, with an integrated ultrasound imaging. The universal temperature-dependent optoacoustic response of blood was employed to convert reconstructed optoacoustic images to temperature maps. Optoacoustic imaging of temperature during prostate cryotherapy was performed in the longitudinal view over a region of 30 mm (long) × 10 mm (deep) that covered the rectum, the Denonvilliers fascia, and the posterior portion of the treated gland. The transrectal optoacoustic images showed high-contrast vascularized regions, which were used for quantitative estimation of local temperature profiles. The constructed temperature maps and their temporal dynamics were consistent with the arrangement of the cryoprobe and readouts of the thermal needle sensors. The temporal profiles of the readouts from the thermal needle sensors and the temporal profile estimated from the normalized optoacoustic intensity of the selected vascularized region showed significant resemblance, except for the initial overshoot, that may be explained as a result of the physiological thermoregulatory compensation. The temperature was mapped with errors not exceeding ±2 °C (standard deviation) consistent with the clinical requirements for monitoring cryotherapy of the prostate. In vivo results showed that the optoacoustic temperature imaging is a promising non-invasive technique for real-time imaging of tissue temperature during cryotherapy of prostate cancer, which can be combined with transrectal ultrasound-the current standard for guiding clinical cryotherapy procedure.

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Section: In Vivo Optoacoustic Temperature Imaging For Image-guided Cr...mentioning

confidence: 99%

In vivooptoacoustic temperature imaging for image-guided cryotherapy of prostate cancer

et al. 2018

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“…For example, if argon is used as the working media, a sudden temperature decrease can be induced at the tip. However, if argon is replaced by high-pressure helium, a temperature increase will occur at the tip [17]. Figure 1 schematically shows one of the structures of the present micro freeze tweezer and its application in stretching an object.…”

Section: Freeze Tweezer To Manipulate Small Objectsmentioning

confidence: 99%

Freeze tweezer to manipulate mini/micro objects

Jing

Zhou

2003

J. Micromech. Microeng.

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In this paper, we propose a freeze tweezer using the freezing force of a small volume of nucleotide ice to manipulate mini/micro objects in an aqueous state. Several prototypes of such a device based on the Joule-Thompson throttling effect have been fabricated and there have been preliminary demonstrations of their applicability in manipulating a wide variety of objects. By regulating the freezing conditions of the cooler, an ice ball can be formed between the tweezer tip and the object it contacts and then the object can be picked up. This freezing force is strong enough to manipulate objects with any shape, electric charge, light or heavy, biological or non-living, on the condition that the contact area can be frozen. Successful manipulation of a series of specific objects presented in this paper indicates that it would be much easier for the freeze tweezer to handle objects with smaller size. Therefore, further nanoscale freeze tweezers following the same idea as above can be put forward; this is expected to have exciting applications in micro/nano engineering field. Furthermore, theoretical analysis and experiments have been performed to quantify the response time of the freeze tweezer and the mechanical force generated on the tweezer tip. This study has also raised quite a few new fundamental issues related to the fabrication and practices of the freeze tweezer.

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“…The cryoablation is onset by circulation of compressed Argon gas inside the hollow probes, which is rapidly cooled below -100C via Joule-Thomson effect. 11,12 Two cycles of fast 5-10 minute freezing followed by thawing is currently the standard clinical procedure approved by FDA. 3 Destruction of the cancerous tissue during cryotherapy occurs by at least three mechanisms 13,14 : (1) at -40C and below -intra-and extracellular formation and fusion of ice crystals, which disrupts membranes and stops cellular metabolism; (2) at -20C and belowdamage to blood vessels interrupting blood flow and creating thrombosis and ischemia; and (3) at 0C and belowinitiation of apoptosis, the programmed cell death cascade.…”

Section: Introductionmentioning

confidence: 99%

In vivo cryoablation of prostate tissue with temperature monitoring by optoacoustic imaging

2016

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Cryoablation of prostate cancer is an FDA approved clinical procedure, which involves repetitive rapid cooling of a lesion to lethal temperatures of -40C and below. The major drawback of the technique is the insufficient control over the fast thermal processes that may result in severe complications (impotence, incontinence, perforation of the rectal wall) and morbidity. The developed optoacoustic imaging technique provides non-invasive real-time temperature mapping of tissue adjacent to prostate and enables more efficient control over the procedure, which is necessary to reduce side effects and accelerate the physician's learning curve. In these studies we successfully demonstrated real-time transrectal optoacoustic imaging during prostate cryoablation in live canine model focused on optoacoustic thermography of the rectal wall within the depth of 1cm. Our method utilized previously discovered universal thermal dependence of the normalized optoacoustic response of blood. Nanosecond-pulse radiation of Ti-Sapphire laser tuned to the isosbestic point of hemoglobin (802±3 nm) was delivered via fiberoptic illuminators assembled on both sides of the linear array of the 128-channel transrectal ultrasound probe. Temperature readouts at discrete locations inside and nearby prostate were also performed using standard transperineal needle sensors. The effect of homeostasis on optoacoustic imaging in live tissue was examined during cooling and shown to be significant only within the range of ±1.5C in respect to the body temperature. Accuracy of in vivo optoacoustic temperature measurements was determined as ±2C for the range of temperature from +35 to -15C, which is more than sufficient for tracking the essential isotherms in the course of clinical procedures.

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Fast Joule-Thomson Cryocycling Device for Cryosurgical Applications

Cited by 15 publications

References 1 publication

In vivooptoacoustic temperature imaging for image-guided cryotherapy of prostate cancer

In vivooptoacoustic temperature imaging for image-guided cryotherapy of prostate cancer

Freeze tweezer to manipulate mini/micro objects

In vivo cryoablation of prostate tissue with temperature monitoring by optoacoustic imaging

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