Imaging

Imaging: Main page

Introduction

8 November 1895, when German physicist Dr W C Roentgen while working on Cathode Rays outside Leonard's tubes, discovered a new ray (which he called X-Ray), he did not realize, his discovery would revolutionize history of physics and imaging field of diagnostic medicine.

He took an X-Ray photograph of his wife's hand, first X-Ray picture of the world and published first paper "On A New Kind of Rays" on 28th December 1895 at the University of Wurzburg. Like all other great scientists he was not aware that his invention will become a landmark in imaging field. But his associates had sensed the forthcoming usefulness of his invention and he was later rewarded with Noble prize in 1901.

This non-invasive procedure provides so much information that many a times no further investigation is required to establish the diagnosis. Rational use of X-Ray and imaging gives us the best yield. Radiation hazards have to be kept in mind and cost benefit ratio has to be established. In addition one should always have DD spelt out before using imaging to either confirm or rule out a possibility.

Among the treating physician, there are mainly two different approaches as far as investigations are concerned. One group of doctors requires a battery of investigations, aimed vaguely in the direction of the patient's symptoms, hoping to get some answer. 'dekh lete hain!' Other group of doctors will decide one or two likely diagnoses and carry out appropriate test to support or refute these possibilities. In the latter group of doctors, yield of investigations is more than the previous one. The second approach is rational, cost effective and it gains the confidence of patient. But for this, the physician has to be well versed with different modalities of the investigation, its know-how and thorough knowledge about the disease itself. Similarly one should have clear idea about the disease progress. This is very useful in follow up of the cases. About 30 - 40 years back there were good prevalence of screening machine in clinic itself. Physicians were using them very randomly; whereas the time interval in the follow up examination should be sensible. Now this method is not used.

Imaging is classified into 9 categories according to its different techniques