WO2019012467A1

WO2019012467A1 - A system and method for detecting a monolayer region in a blood smear slide

Info

Publication number: WO2019012467A1
Application number: PCT/IB2018/055144
Authority: WO
Inventors: Sumit Nath; Nishant Kapoor
Original assignee: Spectral Insights Pvt. Ltd.
Priority date: 2017-07-13
Filing date: 2018-07-12
Publication date: 2019-01-17

Abstract

A system and method for detecting a monolayer region in a blood smear slide is provided. The system for detecting the monolayer region in the blood smear slide includes a non- microscopic image acquisition device configured to obtain one or more images of the blood smear slide to generate at least one blood smear image. The system for detecting the monolayer region in the blood smear slide also includes a segmentation subsystem configured to classify the at least one blood smear image into a plurality of layers based on ontology. The system for detecting the monolayer region in the blood smear slide further includes a detection subsystem configured to detect the monolayer region in the plurality of layers.

Description

A SYSTEM AND METHOD FOR DETECTING A MONOLAYER REGION IN A BLOOD

SMEAR SLIDE

This International Application claims priority from a provisional patent application filed in India having Patent Application No. 201741024914, filed on July 13, 2017 and titled "A SYSTEM AND METHOD FOR DETECTING MONOLAYER REGION IN A BLOOD SMEAR SLIDE".

BACKGROUND

Embodiments of the present disclosure relate to image processing, and more particularly to, a system and method for detecting a monolayer region in a blood smear slide. A blood smear slide is a glass slide on which a thin layer of blood is smeared to prepare the blood smear slide. An area of interest for diagnosis in the blood smear slide is known as a monolayer region. The monolayer region is the area of blood smear in which red blood cells are optimum for examination, separated or barely touching each other with little overlapping.

Conventionally, the monolayer region is detected looking under a microscope at a suitable magnification using objectives of 10X magnification to 100X magnification. The glass slide is placed under the microscope objective and moved in a desired direction manually or through a motorized mechanism to detect a boundary of the monolayer region. However, such method is time consuming since only a small area of the blood smear slide is visible at a time due to the magnification and several instances of magnification at different sections of the blood smear slide are required to determine the location of the monolayer region.

Hence, there is a need for an improved system and method for detecting the monolayer region in the blood smear slide to address the aforementioned issues.

BREIF DESCRIPTION

In accordance with one embodiment of the present disclosure, a system for detecting a monolayer region in a blood smear slide is provided. The system includes a non-microscopic image acquisition device configured to obtain one or more images of the blood smear slide to generate at least one blood smear image. The system also includes a segmentation subsystem configured to classify the at least one blood smear image into a plurality of layers based on ontology. The system further includes a detection subsystem configured to detect the monolayer region in the plurality of layers. In accordance with another embodiment of the present disclosure, a method for detecting a monolayer region in a blood smear slide is provided. The method includes obtaining one or more images of the blood smear slide using a non-microscopic image acquisition device to generate at least one blood smear image. The method also includes classifying the at least one blood smear image into a plurality of layers based on ontology. The method further includes detecting the monolayer region in the plurality of layers.

In accordance with yet another embodiment of the present disclosure, a system for detecting a monolayer region in a blood smear slide is provided. The system includes a hyperspectral image acquisition device configured to obtain one or more hyperspectral images to generate at least one blood smear image. The system also includes a segmentation subsystem configured to classify the at least one blood smear image into a plurality of layers based on ontology. The system further includes a detection subsystem configured to detect the monolayer region in the plurality of layers.

To further clarify the advantages and features of the present disclosure, a more particular description of the disclosure will follow by reference to specific embodiments thereof, which are illustrated in the appended figures. It is to be appreciated that these figures depict only typical embodiments of the disclosure and are therefore not to be considered limiting in scope. The disclosure will be described and explained with additional specificity and detail with the appended figures. BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure will be described and explained with additional specificity and detail with the accompanying figures in which:

FIG. 1 illustrates a schematic representation of a system for detecting a monolayer region in a blood smear slide in accordance with an embodiment of the present disclosure; FIG. 2 illustrates a pictorial representation of an effect of normalization during a high dynamic range (HDR) image generation in accordance with an embodiment of the present disclosure;

FIG. 3 is a block diagram representation of one embodiment of the system for detecting the monolayer region in the blood smear slide of FIG. 1 in accordance with an embodiment of the present disclosure; FIG. 4 is a pictorial representation of the HDR image depicting a plurality of layers in the blood smear image in accordance with an embodiment of the present disclosure;

FIG. 5 is a graphical representation of a spectral response of the plurality of layers in the hyperspectral blood smear image accordance with an embodiment of the present disclosure; and

FIG. 6 illustrates a flow chart representing the steps involved in a method for detecting a monolayer region in a blood smear slide of FIG. 1 in accordance with an embodiment of the present disclosure.

Further, those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.

DETAILED DESCRIPTION

For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as would normally occur to those skilled in the art are to be construed as being within the scope of the present disclosure.

The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more devices or sub-systems or elements or structures or components preceded by "comprises... a" does not, without more constraints, preclude the existence of other devices, sub-systems, elements, structures, components, additional devices, additional sub-systems, additional elements, additional structures or additional components. Appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but not necessarily do, all refer to the same embodiment. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting. In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings. The singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise.

Embodiment of the present disclosure relate to a system and method for detecting a monolayer region in a blood smear slide. The system for detecting the monolayer region in the blood smear slide includes a non-microscopic image acquisition device configured to obtain one or more images of the blood smear slide to generate at least one blood smear image.

The system for detecting the monolayer region in the blood smear slide also includes a segmentation subsystem configured to classify the at least one blood smear image into a plurality of layers based on ontology. The system for detecting the monolayer region in the blood smear slide further includes a detection subsystem configured to detect the monolayer region in the plurality of layers.

FIG. 1 is a schematic representation of a system (10) for detecting a monolayer region in a blood smear slide (20) in accordance with an embodiment of the present disclosure. The system (10) for detecting the monolayer region in the blood smear slide (20) includes a non- microscopic image acquisition device (30) configured to obtain one or more images of the blood smear slide to generate at least one blood smear image.

The system (10) also includes the segmentation subsystem (40) configured to classify the at least one blood smear image into the plurality of layers based on ontology. The system (10) further includes the detection subsystem (50) configured to detect the monolayer region in the plurality of layers.

In operation, the blood smear slide (20) is prepared using standard procedures for detecting the monolayer region in the blood smear slide (20). Subsequently, one or more images of the blood smear slide (20) are obtained using the non-microscopic image acquisition device (30) to generate at least one blood smear image (FIG. 2). In one embodiment, the one or more images of the blood smear slide (20) may be obtained manually, where an operator may manually operate the non-microscopic image acquisition device (30) to obtain the one or more images of the blood smear slide (20). In another embodiment, the one or more images may be obtained automatically using the non-microscopic image acquisition device (30). In such an embodiment, the blood smear slide (20) may be placed on a conveyor system to automatically obtain the one or more images of the blood smear slide (20). In both the aforementioned embodiments, the non-microscopic image acquisition device (30) is placed at a viewing distance with respect to the blood smear slide (20) to obtain the one or more images of the blood smear slide (20). In some embodiments, the system (10) may include a light source (60) that may be configured to provide a light exposure on the blood smear slide (20) while obtaining the one or more images of the blood smear slide (20). In such embodiment, the light exposure on the blood smear slide (20) may be from the bottom of the blood smear slide (20). The one or more images of the blood smear slide (20) may be obtained in the light transmission mode.

In one embodiment, the illumination of the blood smear slide (20) may be varied to obtain a desired blood smear image. In one embodiment, the illumination may be varied by varying luminosity of the light exposure. In another embodiment, the illumination may be varied by varying a shutter speed of the non-microscopic image acquisition device (30).

Furthermore, upon illumination of the blood smear slide (20), the non-microscopic image acquisition device (30) obtains the one or more images of the blood smear slide (20) and generates at least one blood smear image by stitching the one or more images of the blood smear slide (20) to form the at least one blood smear image. In one embodiment, the non-microscopic image acquisition device (30) may include a digital camera. In a specific embodiment, the digital camera may include a colour camera, a monochrome camera, or a charge coupled device (CCD). In such embodiments, the at least one blood smear image obtained from the one or more images of the blood smear slide (20) is white normalized to generate at least one high dynamic resolution (HDR) image. FIG. 2(a)-2(c) illustrate a pictorial representation (70) of an effect of normalization on the at least one blood smear image to generate the high dynamic range (HDR) image in accordance with an embodiment of the present disclosure. FIG. 2 (a) (80) represents the at least one blood smear image that is white normalized using various image processing techniques to generate the high dynamic range (HDR) image. FIG. 2(b) (90) depicts an intermediate step of white normalization during the generation of the HDR image showing the effect of white normalization on the at least one blood smear image. FIG. 2(c) (100) depicts the HDR image generated from the at least one blood smear image. Referring to FIG. 1, in some embodiments, the non-microscopic image acquisition device (30) may include a hyperspectral camera (110) as shown in FIG. 3. In such embodiments, the hyperspectral camera (110) is configured to obtain one or more hyperspectral images of the blood smear slide (20). The one or more hyperspectral images are analysed to identify boundaries of the blood smear to generate the at least one blood smear image. In such embodiments, the at least one blood smear image is a hyperspectral blood smear image. In one embodiment, hyperspectral imaging may be achieved by a broad level illumination method, a multi light emitting diode (LED) illumination method or a spectral reconstruction method. In another embodiment, hyperspectral imaging may be achieved by a plurality of filter wheels method, a line scan method, a push broom method or a plurality of snapshots method.

Referring back to FIG. 1, the system (10) further includes a segmentation subsystem (40) which is configured to classify of the at least one blood smear image into a plurality of layers based on ontology. As used herein, ontology is an order in which the plurality of layers is formed. In one embodiment, the plurality of layers may include a first layer (130), a second layer (140) and a third layer (150). In a specific embodiment, a plurality of layer may include a feathered layer, a monolayer and a thick layer.

In one embodiment, the segmentation subsystem (40) classifies the HDR image (100) generated from the at least one blood smear image into plurality of layers as shown in FIG. 4. FIG. 4(a) (160) represents the at least one blood smear image obtained from the stitching of the one or more images of the blood smear slide. FIG. 4(b) (170) depicts the corresponding HDR image (100) of the at least one blood smear image. FIG. 4(c) (180) depicts a classified HDR image generated from the segmentation and classification of the corresponding HDR image (100) of the at least one blood smear image.

In one embodiment, the classification of the at least one blood smear image into a plurality of layers may be performed using a k-means clustering method. In another embodiment, the classification of the at least one blood smear image into a plurality of layers may be performed based on the extraction of a plurality of data points from the at least one blood smear image. In such embodiment, the plurality of data points may include a plurality of pixel values of the at least one blood smear image. In one embodiment, the segmentation subsystem (40) of FIG. 3 may be configured to classify the hyperspectral blood smear image into the plurality of layers by obtaining the spectral response of the hyperspectral blood smear image. The spectral response shows the classification of the hyperspectral blood smear image into first layer (130), the second layer (140) and the third layer (150) which may be visible separately with the ranges of spectrum using the spectral response.

FIG. 5 illustrates a graphical representation (190) of a spectral response (200) of the plurality of layers in an exemplary hyperspectral blood smear image in accordance with an embodiment of the present disclosure. The spectral response (200) is a plot between wavelength in nano metres (X-axis) (210) and reflectance or transmittance (Y-axis) (220). Curve (A) represents a spectrum of the first layer (130) depicting the feathered region. Curve (B) represents a spectrum of the second layer (140) depicting the monolayer region. Curve (C) represents a spectrum of third layer (150) depicting the thick layer.

With continued FIG. 1, system also include a detection subsystem (50) which is configured to detect the monolayer region in the plurality of layers. In a specific embodiment, the monolayer region may be detected between the first layer (130) and the third layer (150). In some embodiments, the detection subsystem (50) generates a notification when monolayer region is undetected.

In one embodiment, the system (10) for detecting the monolayer region in the blood smear slide may be operatively coupled to a microscope for detecting the monolayer region in the blood smear slide (20).

In some embodiments, the system may be used for detection of monolayer region in any bright field, fluorescence microscopic imaging such as Histology or Microbiology. In another embodiment, the system may also be applicable in reflectance imaging such as Metallurgy.

FIG. 6 illustrates a flow chart representing the steps involved in a method (230) for detecting a monolayer region in a blood smear slide of FIG. 1 in accordance with an embodiment of the present disclosure. The method (230) for detecting monolayer region in a blood smear slide includes obtaining one or more images of the blood smear slide using a non-microscopic image acquisition device to generate at least one blood smear image in step 240. In one embodiment, obtaining the one or more images of the blood smear slide using the non -microscopic image acquisition device may include obtaining the one or more images by illuminating the blood smear slide using a light exposure. In a specific embodiment, the method (230) may include illuminating the blood smear slide by varying luminosity of the light exposure or by varying shutter speed of the non -microscopic image acquisition device.

In some embodiments, obtaining the one or more images of the blood smear slide using the non-microscopic image acquisition device may include obtaining the one or more images of the blood smear slide at a viewing distance.

In one embodiment, generating the at least one blood smear image may include generating at least one high dynamic range (HDR) image based on the one or more images of the blood smear slide. In a specific embodiment, generating the at least one high dynamic range (HDR) image based on the one or more images of the blood smear slide may include normalizing the one or more images of the blood smear slide prior to generating the at least one high dynamic range (HDR) image.

The method (230) for detecting a monolayer region in the blood smear slide also includes classifying the at least one blood smear image into a plurality of layers based on ontology in step 250. In one embodiment, classifying the at least one blood smear image into the plurality of layers may include classifying the at least one blood smear image using a k-means clustering method.

In another embodiment, classifying the at least one blood smear image into the plurality of layers may include extracting a plurality of data points from the at least one blood smear image. In yet another embodiment, classifying the at least one blood smear image into the plurality of layers may include classifying the plurality of layers into a first layer, a second layer and a third layer.

The method (230) for detecting the monolayer region in the blood smear slide further includes detecting the monolayer region in the plurality of layers in step in step 260. In one embodiment, detecting the monolayer region in the plurality of layers may include detecting the monolayer region between the first layer and the third layer.

In one embodiment, the method (230) may include generating a notification when the monolayer region is undetected. Various embodiments of the system and method for detecting the monolayer region in the blood smear slide enables faster detection of monolayer region in the blood smear slide due to faster imaging and computation of one or more images of the blood smear slide.

Also, the detection subsystem enables identification of a poorly prepared blood smear slide by generating a notification when the monolayer region is undetected in the blood smear slide. Furthermore, the system for detecting the monolayer region enables generation of the at least one blood smear image without the need of a lab environment as there is no need to insert the blood smear slide under a microscope.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the disclosure and are not intended to be restrictive thereof.

While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person skilled in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, order of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts need to be necessarily performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.

Claims

WE CLAIM:

1. A method (280) for detecting a monolayer region in a blood smear slide

comprising: obtaining one or more images of the blood smear slide using a non-microscopic image acquisition device to generate at least one blood smear image; classifying the at least one blood smear image into a plurality of layers based on ontology; and detecting the monolayer region in the plurality of layers.

2. The method (280) as claimed in claim 1, wherein obtaining the one or more images of the blood smear slide using the non-microscopic image acquisition device comprises obtaining the one or more images by illuminating the blood smear slide using a light exposure.

3. The method (280) as claimed in claim 2, wherein illuminating the blood smear slide by varying luminosity of the light exposure or by varying shutter speed of the non- microscopic image acquisition device.

4. The method (280) as claimed in claim 1, wherein obtaining the one or more images of the blood smear slide using the non-microscopic image acquisition device comprises obtaining the one or more images of the blood smear slide at a viewing distance.

5. The method (280) as claimed in claim 1, wherein generating the at least one blood smear image comprises generating at least one high dynamic range (HDR) image based on the one or more images of the blood smear slide.

6. The method (280) as claimed in claim 5, wherein generating the at least one high dynamic range (HDR) image based on the one or more images of the blood smear slide comprises normalizing the one or more images of the blood smear slide prior to generating the at least one high dynamic range (HDR) image.

7. The method (280) as claimed in claim 1, wherein classifying the at least one blood smear image into the plurality of layers comprises classifying the at least one blood smear image using a k-means clustering method.

8. The method (280) as claimed in claim 1, wherein classifying the at least one blood smear image into the plurality of layers comprises extracting a plurality of data points from the at least one blood smear image.

9. The method (280) as claimed in claim 1, wherein classifying the at least one blood smear image into the plurality of layers comprises classifying the plurality of layers into a first layer, a second layer and a third layer.

10. The method (280) as claimed in claim 1, wherein detecting the monolayer region in the plurality of layers comprises detecting the monolayer region between the first layer and the third layer.

11. The method (280) as claimed in claim 1, further comprising generating a notification when the monolayer region is undetected.

12. A system (10) for detecting a monolayer region in a blood smear slide (30) comprising: a non-microscopic image acquisition device (40) configured to obtain one or more images of the blood smear slide (30) to generate at least one blood smear image; a segmentation subsystem (50) configured to classify the at least one blood smear image into a plurality of layers based on ontology; and a detection subsystem (60) configured to detect the monolayer region in the plurality of layers.

13. The system (10) as claimed in claim 12, wherein the non-microscopic image acquisition device (40) comprises a hyperspectral camera or a digital camera.

14. The system (10) as claimed in claim 13, wherein the digital camera comprises a colour camera, a monochrome camera, or a charge coupled device (CCD).

15. The system (10) as claimed in claim 12, further comprising a light source (70) configured to provide a light exposure on to the blood smear slide.

16. A system (110) for detecting a monolayer region in a blood smear slide (30) comprising: a hyperspectral image acquisition device (120) configured to obtain one or more hyperspectral images to generate at least one blood smear image; a segmentation subsystem (130) configured to classify the at least one blood smear image into a plurality of layers based on ontology; and a detection subsystem (140) configured to detect the monolayer region in the plurality of layers.