Method and apparatus for automated image analysis of biological specimens

• US 7,783,098 B2
• Filed: 08/29/2008
• Issued: 08/24/2010
• Est. Priority Date: 11/30/1995
• Status: Expired due to Fees

• Current Assignee: Carl Zeiss Microscopy GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: CARL Zeiss Microimaging GmbH (Carl-Zeiss-Stiftung)
• Inventors: Decker, William J., Riding, Thomas J., Ring, James E., McLaren, Gina, Douglass, James W., Ellis, Robert T.
• Primary Examiner(s): PATEL, KANJIBHAI B
• Application Number:
  US12/201,800
• Publication Number:
  US 20090060303A1
• Time in Patent Office: 725 Days
• Field of Search: 382128-134, 382/255, 382/274, 382/305, 382/312, 345/150, 348/577, 348/645, 348/650, 355/55
• US Class Current: 382/128
• CPC Class Codes: G01N 1/312 for samples mounted on planar substrates
• CPC Class Codes: G01N 15/1433 using image recognition
• CPC Class Codes: G01N 15/1468 with spatial resolution of the texture or inner structure of the particle
• CPC Class Codes: G01N 2015/1472 with colour
• CPC Class Codes: G01N 2015/1488 Methods for deciding
• CPC Class Codes: G01N 2015/1497 Particle shape
• CPC Class Codes: G02B 21/244 using image analysis techniques
• CPC Class Codes: G02B 21/367 providing an output produced by processing a plurality of individual source images, e.g. image tiling, montage, composite images, depth sectioning, image comparison
• CPC Class Codes: G06T 7/60 Analysis of geometric attributes
• CPC Class Codes: G06V 20/69 Microscopic objects, e.g. biological cells or cellular parts
• CPC Class Codes: G06V 20/693 Acquisition

Abstract

A method including acquiring images of medical slides at a plurality of different focus positions, determining a position which produces a maximum value of pixel values relative to a pixel value mean, wherein said determining comprises using a pixel value mean as a coarse estimate of coarse focus position, and subsequently refining said coarse focus position to find a fine focus position, and wherein said refining comprises fitting to a polynomial, and using a specified portion of the polynomial as a fine estimate of focus position, and producing a focus control signal that is related to said maximum value to control a focus position.

Claims

1. A method of focusing, comprising:

acquiring, with an imaging device, a first electronic image of at least a portion of a slide presenting a medical sample;

varying a focus of said slide by changing a distance between said slide and the imaging device to acquire a second electronic image;

based on the acquiring and varying, fitting at least one characteristic of the first and second images to a Gaussian function;

using said fitting to select an optimum focus by positioning the slide at a specified distance from the imaging device relative to a peak of said Gaussian function as an estimate of a coarse focus position;

determining a fine focus position by finding a least squares fit to a second order polynomial; and

positioning the imaging device at the fine focus position.

2. A method of focusing comprising;

acquiring images of a medical slide at a plurality of focus positions using an imaging device;

using a computer to determine a focus position for the imaging device, the computer programmed with an algorithm for first determining a position that produces a maximum value of pixel values relative to a pixel value mean, said determining comprising using said pixel value mean as a coarse estimate of coarse focus position, and next refining said coarse focus position to find a fine focus position, said refining comprising fitting to a polynomial and using a specified portion of the polynomial as a fine estimate of focus position;

producing a focus control signal that is related to said maximum value to position the imaging device at said focus position.

3. A method for histological reconstruction to simultaneously analyze multiple fields of view, said method comprising:

providing a stained cellular specimen for identification of objects of interest;

generating images of the cellular specimen using an optical sensing array, each of the images being smaller than the entire stained cellular specimen; and

using a processor programmed with an algorithm to digitize each of said images to form corresponding digitized images, couple said stored digitized images of the cellular specimen together in an order to form a composite image; and

pair the composite image of the stained slide with an immunohistochemistry slide so that analysis of the digitized images can be performed simultaneously, said analysis including processing the composite image to find objects of interest.