Design of a Surgical Pen-Type Probe for Real-Time Indocyanine Green Fluorescence Emission Diagnosis

2021 ◽  
Author(s):  
Ki-Cheol Yoon ◽  
Kwang Gi Kim ◽  
Seung Hoon Lee

Abstract The advantage of handheld type surgical microscope is that the size of the probe is small and light, and the working distance(o to 30 cm) and field of view (306°) can be adjusted. Also, a short working distance will minimize the loss of light source energy. However, the currently developed handheld type surgical microscope is still large, heavy, and uses relatively high energy (600 mW). Also, it is not suitable for portable use. To address the aforementioned problems, this study aimed to develop a pen-type surgical fluorescence microscope that is compact, portable, and has an adjustable beam angle and working distance. The pen-type probe consists of a laser diode, CMOS camera, light source brightness control device, filter, and power switch. The IR-cut filter inside the CMOS camera was removed to facilitate transmission of the fluorescence emission wavelength. In addition, a long-pass filter was attached to the camera so that the external light source was blocked and only the fluorescence emission wavelength was allowed to pass through. The pen-type probe was manufactured using 3D printing, and the captured image was designed to be observed through an external monitor. The performance of the pen-type probe was tested through a large animal experiment. Indocyanine green (2.5mg/kg) was injected into a pig's vein. Fluorescence emission of 805-830 nm was achieved by irradiating an external light source (785 nm and 4 mW/cm2), and liver-uptake occurred after 2.4 minutes.

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1571
Author(s):  
Jinkyu Kim ◽  
Kicheol Yoon ◽  
Kwanggi Kim

The goal of oncological surgery is to completely remove the tumor. Tumors are often difficult to observe with the naked eye because of the presence of numerous blood vessels and the fact the colors of the tumor and blood vessels are similar. Therefore, a fluorescent contrast medium using a surgical microscope is used to observe the removal status of the tumor. To observe the tumor removal status using a fluorescent contrast agent, fluorescence is expressed in the tumor by irradiating with an external light source, and the expressed tumor can be confirmed through a surgical microscope. However, not only fluorescence-expressed tumors are observed under a surgical microscope, but images from an external light source are also mixed and observed. Therefore, since the surgical microscope is connected to a filter, the quality of the diagnostic image is not uniform, and it is difficult to achieve a clear observation. As a result, an asymmetric image quality phenomenon occurs in the diagnostic images. In this paper, a filter with high clarity that provides a symmetrical observation of diagnostic images is developed and manufactured.


Author(s):  
So Yoon Kwon ◽  
Ki-Cheol Yoon ◽  
Kwang Gi Kim

Abstract Inside the brain tumor, the blood vessels are intricately composed, and the tumors and blood vessels are similar in color. Therefore, when observing tumors and blood vessels with the naked eye or a surgical microscope, it is difficult to distinguish between tumors and blood vessels. Fluorescence staining with indocyanine green (ICG) is performed to distinguish between brain tumors and blood vessels using a surgical microscope. However, when observing the blood circulation state of a tumor or blood vessel through a surgical microscope, light reflection occurs from the camera. In the process of observing the state of the blood vessel, due to the occurrence of light reflection, an obstruction phenomenon in which the observation field is blocked by the blood vessel of the object to be observed occurs. Therefore, it is difficult to diagnose the vascular condition. In this experiment, the 780nm light-emitting diode (LED) was irradiated to the ICG phantom, and then, when the fluorescence expression image was observed, the polarizing filter such as circular polarized light (CPL) filter and linear polarized light (LPL) filter were inserted into the camera and the reflected light was reduced. Therefore, it is possible to reduce the reflected light from the fluorescence expression image by using a polarizing filter, and it is expected to be applicable to surgery and diagnostic fields of cancer such as surgery.


The Analyst ◽  
2021 ◽  
Author(s):  
Stephanie K. Loeb ◽  
Haoran Wei ◽  
Jae-Hong Kim

The fluorescence emission wavelength shift of CdSe quantum dots due to heat-induced lattice dilatation is used to spatially resolve temperatures in solar photothermal systems.


Author(s):  
So Yoon Kwon ◽  
Ki-Cheol Yoon ◽  
Kwang Gi Kim

Abstract Most brain surgeries aim to completely resection a tumor. However, the arrangement of blood vessels around brain tumors is often complex. Moreover, the tumors and blood vessels have similar colors, making it difficult to identify the boundaries between them with the naked eye. Fluorescent staining is a method used to distinguish the borders between brain tumors and blood vessels. The fluorescent contrast agents commonly used to observe tumors are 5-aminolevulinic acid (5-ALA) and fluorescein sodium (FS), which have different surgical sensitivities, depending on the type of tumor. In this article, a dual band band-pass filter (BPF) with dual-wavelength emission for 5-ALA and FS is designed, and the dual-band BPF capable of inducing simultaneous fluorescence emission of FS and 5-ALA was investigated experimentally to improve accuracy, speed, and energy efficiency in clinical settings. The possibility of dual fluorescence emission with a single irradiation is proposed. The proposed fluorescent dual-band filter has the advantage of saving energy, reducing auxiliary manpower and unit costs, and reducing operating room space requirements by producing two fluorescence diagnostic effects using a single equipment.


Sign in / Sign up

Export Citation Format

Share Document