Spectrum of doctors and healthcare facilities 1

Just like there is spectrum of diseases from very mild to profoundly serious; doctors, laboratories, hospitals and other healthcare facilities have a wide spectrum in the services they provide, their capability and quality. This can lead to considerable amount of confusion and mistrust.

Let us take the example of a CT scan, which is manufactured by different companies. Machines belonging to different companies come with the usual industry standards. Every company tries to innovate and improve the specifications to better the standards. It is a continuous process. There will be some variation in the specifications based on the company, which may or may not affect the image quality.

The first-generation CT scanners (1972) used to take a single cross-sectional image of the body in one direction – across the body (Axial), hence they used to be called CAT scan, meaning Computerized Axial Tomography. The person is made to lie on scanning table which moves through a gantry (like a big donut). The table moves in increments of 2-10 mm for each section to be taken. The process is repeated until the body part that needs to be checked has passed through the scanner.

First generation scanner took about 5 minutes for each section. Since the initial scanners used to take time, 10mm sections were taken to reduce the time and the person must hold breath to scan chest and abdomen as any movement would affect the image quality. So, any lesion in abdomen smaller than 10mm can be missed. With further developments in technology in 70s and 80s it was possible to bring scan times substantially to about a couple of minutes for a brain scan and 5-10 minute for a body scan.

Major technology breakthrough in slip ring technology in 90s resulted in Spiral CT where the scanning table moves continuously through a continuously rotating gantry, making it possible to scan the body in a breath-hold. Further developments like multiple row detector scanners with 4, 8, 16, 32, 64, 128, 256 and now 320 row detectors. These state-of-art scanners further reduced the scan time, made it possible to obtain sections of less than a millimeter. Several hardware and software developments reduced the radiation dose by 2-3 fold.

The entire abdomen can be scanned in a single breath hold within 10 - 15 seconds. Sometimes a contrast injection is given to enhance the tissues scan is repeated. Timing of the injection and acquiring the images is important. In addition to increasing the resolution, the reduction in scanning time is especially important while scanning moving body parts like heart. The scanning can be done with less than 1mm sections and using software, the images can be recreated in three dimensions and viewed in any direction we want, not just the axial view. That is the reason the “Axial” is dropped from CAT.

To put into perspective, it is like taking photos using the early 1 mega pixel camera and the latest 108 mega pixel camera. The clarity of image is much better with the latest scanners and small lesions can be picked up. But increased image quality does not always equate with better diagnosis after a certain level.

New features are being added to the scanners and the latest scanners always costs money to buy. State of the art scanners are not available everywhere. Most centers in periphery do not have the latest machines. For majority of the patients, even images taken on previous generation scanners are good enough. Sometimes, when patients come for second opinion or treatment in a higher center, , if the image quality is not optimal for the clinical question to be answered, the scan may need to be repeated. This does not go down well with the patients as they must pay again for the scan of same name and they feel cheated.

The same situation can happen across all tests that are being done to diagnose a patient’s condition. For laboratory tests, equipment quality, maintenance, calibration and even the way sample is collected are important to get correct results. Sometimes it is counterproductive to believe the reports from other places for a variety of reasons. It is better to get the tests repeated to give second opinion or treat. For many doctors, it is not easy to explain all the above matter to the patient, increasing the gap in communication and mistrust.