Page 35 - Textbook of Pathology, 6th Edition

with silver (AgNOR technique). NORs appear as black 4. Image analysis software installed in the computer system 19
intranuclear dots while the background is stained yellow- according to the requirement of the user for making
brown. measurements and calculations.
APPLICATIONS. Image analyser can be used for various
COMPUTERS IN PATHOLOGY LABORATORY purposes as under:
A busy pathology laboratory has a lot of data to be 1. Morphometric study of tumour cells by measurement of CHAPTER 2
communicated to the clinicians. Pathologist too requires access architectural, cellular and nuclear features.
to patient’s data prior to reporting of results on specimens 2. Quantitative nuclear DNA ploidy measurement.
received. It is, therefore, imperative that a modern pathology 3. Quantitative valuation of immunohistochemical staining.
laboratory has laboratory information system (LIS) which
should be ideally connected to hospital information system DNA MICROARRAYS
(HIS). DNA microarray is the newer application of silicon chip
Besides, the laboratory staff and doctors should have technology for simultaneous analysis of large volume of data
adequate computer literacy on these systems. pertaining to human genes such as detection and
There are two main purposes of having computers in the quantification of point mutation and single nuceotide
laboratory: pleomorphism. The method eliminates use of DNA probes.
for the billing of patients’ investigations; and Instead fluorescent labelling of an array of DNA fragment
for reporting of results of tests in numeric, narrative and (complimentary or cDNA) is used to hybridise with target
graphic format. from test sample. High resolution laser scanners are used for
Applications. Application of computers in the pathology detecting fluorescent signals emitted, while the level of gene Techniques for the Study of Pathology
laboratory has several advantages as under: expression and genotyping of the biologic samples is
1. The laboratory as well as the hospital staff have access to measured by application of bioinformatics.
information pertaining to the patient which helps in improving APPLICATIONS. DNA microarrays is used for molecular
patientcare. profiling of tumours which aids in arriving at specific
2. The turn-around time (i.e. time between specimen collec- histogenetic diagnosis and predicting prognosis.
tion and reporting of results) of any test is shortened.
3. It improves productivity of laboratory staff at all levels who LASER MICRODISSECTION
can be utilised for other jobs.
4. Coding and indexing of results and data of different tests Laser microdissection is another newer technique in
are possible on computer system. diagnostic surgical pathology for carrying out molecular
5. For research purposes and getting accreditation so as to get profiling on tissue material. It involves dissection of a single
grants for research, computerised data of results are cell or part of the cell (e.g. chromosomes) by sophisticated
mandatory. laser technology and employs software for the procedure. The
6. Storage and retrieval of laboratory data to save time and space isolated material can then be used for performing available
occupied by the records. molecular tests.

SPEECH RECOGNITION SYSTEM. Computer systems are TELEPATHOLOGY AND VIRTUAL MICROSCOPY
now available which can recognise and transform spoken
words of gross and microscopic description of reports through Telepathology is defined as the practice of diagnostic pathology
dictaphone into text without the use of secretarial staff. by a remote pathologist utilising images of tissue specimens
transmitted over a telecommunications network. The main
IMAGE ANALYSER AND MORPHOMETRY components of a telepathology system are as under:
Conventional light microscope.
Pathology is very visual subject and hence analysis of Method of image capture, commonly a camera mounted
microscopic images forms the main plank of its study. There on light microscope.
has been need as well as desire to impart more and more Telecommunications link between sending and receiving
objectivity to the rather subjective reports of histopatholgogy. side.
Now, with advances in computing techniques, objective Workstation at receiving end with a high quality
measurement of microscopic features quantitatively to impart monitor.
reproducibility in histopathology has been achieved. Depending upon need and budget, telepathology system
Image analyser is a system that is used to perform is of two types:
measurement of architectural, cellular and nuclear features Static (store-and-forward, passive telepathology): In this,
of cells. Briefly, the image analyser consists of the following: selected images are captured, stored and then transmitted
1. Standard light microscope with a video camera mounted over the internet via e-mail attachment, file transfer protocol,
it. web page or CD-ROM. It is quite inexpensive and is more
2. A computer system (CPU, monitor, key board, mouse etc) common but suffers from disadvantage of having sender’s
connected to the microscope. bias in selection of transmitted images.
3. An image capture board to convert displayed video image Dynamic (Robotic interactive telepathology): Here, the
on the monitor into digital image and store it in the CPU. images are transmitted in real-time from a remote