Method and apparatus for optical detection of bio-contaminants within a lumen
A method for optical detection of residual soil in lumens of lumened or cannulated devices such as surgical endoscopes, after undergoing a decontamination process (e.g., a washing or rinsing operation). A soil detection system provides an indication of the presence of residual soil within a lumen by detecting luminescent radiation emanating from the soil on the interior of the lumen in response to excitation light.
1. A soil detection system for detecting presence of soil in a cannulated structure, the soil detection system comprising:
a probe for insertion into an interior of the cannulated structure to detect a fluorescent agent bound to residual soil present on the interior of the cannulated structure, the fluorescent agent emitting fluorescent light at a fluorescence wavelength indicative of soil in response to excitation light at an excitation wavelength;
a light source for producing the excitation light at the excitation wavelength, transmitted through a distal end of the probe into the interior of the cannulated structure;
a light filter for filtering light emanating from the interior of the cannulated structure, said light emanating from said interior including the excitation light reflected by the interior at the excitation wavelength and the fluorescent light at the fluorescence wavelength emitted by exciting the fluorescent agent bound to the soil with the excitation light, said light filter configured to pass the fluorescent light indicative of soil;
a photodetector for detecting the filtered fluorescent light emanating from said interior and generating a light signal corresponding thereto; and
a processing unit for receiving the light signal generated by the detector to determine a presence of soil on the interior based upon features detected at the fluorescence wavelength within the interior of the cannulated structure,
wherein the processing unit detects instances of fluorescence intensity above a threshold in the light signal, which correspond to locations of an unacceptable level of residual soil within the interior of the cannulated structure, and
wherein the instances of fluorescence intensity above the threshold are correlated with their respective distances along a longitudinal axis of the cannulated structure to determine specific locations within the interior of the cannulated structure at which an unacceptable level of soil is present, and a longitudinal display corresponding to a length of the cannulated structure, for displaying locations within the cannulated structure where spots of residual soil are detected.
2. The soil detection system according to claim 1 , wherein the cannulated structure comprises a lumen of a medical instrument.
3. The soil detection system according to claim 2 , wherein the medical instrument is an endoscope.
4. The soil detection system according to claim 2 , wherein the cannulated structure comprises pipes or tubes included in industrial equipment requiring inspection for organic residues.
5. The soil detection system according to claim 1 , wherein the probe comprises an optical fiber that enables simultaneous transmission of the emitted excitation light and the detected filtered fluorescent light.
6. The soil detection system according to claim 5 , wherein the optical fiber comprises a lens at a tip of the optical fiber.
7. The soil detection system according to claim 6 , wherein the lens at the tip of the optical fiber is one of a hemispheric lens and a ball lens.
8. The soil detection system according to claim 1 , wherein the fluorescent agent is fluorescein.
9. The soil detection system according to claim 1 , further comprising a coupler for optically connecting the light source and the photodetector to the probe.
10. The soil detection system according to claim 1 , wherein the excitation light from the light source is at a wavelength of about 488-490 nm, wherein the fluorescent light is at wavelength of about 513 nm.
11. The soil detection system according to claim 1 , further comprising a user interface for displaying an output of the processing unit indicative of the presence of soil within the interior of the cannulated structure based upon features detected at the fluorescence wavelength.
12. The soil detection system according to claim 1 , wherein an intensity level indicated by the threshold can be selectively adjusted to correspond with a predetermined cleanliness level.
13. The soil detection system according claim 1 , wherein the longitudinal display includes at least one alert message for indicating a status of a cannulated structure inspection process.
14. The soil detection system according to claim 1 , further comprising a probe reel for spooling and unspooling the probe.
15. The soil detection system according to claim 1 , wherein the probe further comprises an image sensor for providing a view of the interior of the cannulated structure.