Issuu on Google+

Special Focus article

Powering Diagnosis CT scanners facilitate visualisation, characterisation, and measurement of biological processes at the molecular and cellular levels in humans and other living systems

By Dhirendra Pratap Singh


he late 70s and early 80s saw entry of first ultrasound and single slice translate-rotate CT scanners in India, suddenly emerging like sphinx and transforming the status of imaging technology from just simple hardware producing flat two dimensional images into orthogonal cross-sectional images of higher special and temporal resolution which revealed much more in terms of human anatomy and offered higher accuracy in diagnosis. This placed the radiologist in the driver’s seat in the clinical world and brought

greater respect to him as the one whose acumen was necessary to get the diagnosis in most cases which was based on management of the diseases. Molecular imaging enables the visualisation of the cellular function and the follow-up of the molecular process in human body without perturbing it. Thus, it was quickly adopted by the medical fraternity, giving a noninvasive method with clarity . This technique helps improve the treatment of diseases such as cancer, neurological and cardiovascular diseases by optimising the september / 2011



Special Focus

New Technology, New Prospects Dual source CT scanners are the latest revolution in the field of CT imaging. There are multi-slice CT scanners which have the capability of rapidly scanning large longitudinal (z) volume with high z-axis resolution. Multi Slice CT is a light speed VCT. Its unprecedented coverage speed allows clinicians to capture whole organs in a second, the heart in 5 beats, or go head to toe in less than 10 seconds. In the course of a Single Photon Emission Computed Tomography (SPECT) scan, a three-dimensional image is obtained by rotating the detectors of the gamma camera around the patient. For evaluation, slices in any orientation can be reconstructed from the original three-dimensional scan. SPECT is a well-established imaging method that is widely used in modern nuclear medicine diagnostics. In particular, tomographic scans have almost completely replaced planar acquisitions in the fields of cardiology and neurology. PET scanning is a nuclear medicine procedure that deals with positrons. The positrons annihilate to produce two opposite travelling gamma rays to be detected coincidentally, thus improving resolution. With the introduction of improved instruments allowing acquisition of whole body images in under an hour, applications in oncology have opened avenues for expanded clinical use of PET.

Future in radiology will see enhanced efforts towards greater use of molecular imaging to be able to detect lesions before they attain even pin-head size and which are yet only at cellular levels

pre-clinical and clinical tests of new medication. They are also expected to have a major economic impact due to earlier and more precise diagnosis. CT scanners facilitate visualisation, characterisation, and measurement of biological processes at the molecular and cellular levels in humans and other living systems. Molecular imaging is a key component of 21st century cancer management. The global efforts for quantitative imaging of tumor can lead to a more robust and effective monitoring of personalised molecular cancer therapy. Treatment for cancer is traumatic as the disease grows inaccurately and partial diagnosis often leads to more traumas. Molecular Imaging can be very useful not only in oncology but in many more clinical areas. High end imaging modalities need better image management and archival systems. The diagnostic outcome of molecular imaging is necessary to


september / 2011

be made available to clinicians treating the patients. Healthcare IT and molecular imaging go hand in hand. If one wishes to exploit the real advantage of these systems, other should ensure effective distribution of these images to clinicians and integration with electronic medical records. When a hospital plans to buy a multi-crore, hitech equipment, the initial few months of planning are typically spent over the question, “What return on investment (ROI) can we expect?� Most imaging equipments have gone through this phase and have matured in terms of both utility and viability. Molecular Imaging, the latest technology wave in diagnostic imaging is not an exception. But for a diagnostic consultant return on investment is measured differently. How many times is a life saved due to timely diagnosis? How many times the quality of life has dramatically improved the treatment with accurate predictions and visualisation of the disease? Answers to these questions are the basis for real ROI.

Market The demand for medical imaging products in the US market was $21.4 billion in 2010. The main causes of this growth are technological advances, along with an ageing population and changing trends in healthcare approaches. New scanners with expanded testing capabilities are also being adopted widely by hospitals and outpatient facilities to improve quality of care. Medical imaging equipment has posted demand of over $16 billion in 2010, which is 6.8 percent higher than the annual growth in the last two years. Picking up the biggest pace will be multi-slice CT scanners, due to investment in the systems by hospitals and outpatient facilities replacing older systems. Due to the popularity of new hybrid PET/CT systems, the systems offer dual anatomical and metabolic scanning capabilities. Other drivers of the demand include the ongoing replacement of conventional analog machines with digital x-ray and radiographic fluoroscopy systems. Faring better will be nuclear medicine and ultrasound equipments. New four-dimensional (4D) imaging systems and new laptop and hand-held devices for point-of-care systems will also abet the overall growth for diagnostic ultrasound equipment. Worldwide, medical imaging consumables have expanded 3.6 percent annually to $5.3 billion in 2010. Finally, the market for contrast agents have seen the moderate growth in x-ray, CT and MRI studies on body regions where the targeted organ or tissue needs visual enhancement due to its masking by nearby invivo matter. In this product group, nano-sized compounds hold the best growth prospects as they are expected to greatly improve MRI-generated images.

Special Focus article

     


        

 •  •  •      •    •     

                 

                   • 

  

•   •     •   •    

•    • 

    •      •      •     •  •               •           •    • 

  • • • • •

          

 



 

 

  


 

•      •     •    •    

 

  

  

 

•  • 

      

 

 

 

september / 2011



Special Focus

CT Scanners:

Setting new standards in the treatment of heart disease (Non-invasive alternatives) Compared to the other imaging modalities, how are CT Scanners unique and what do they offer to radiologists? CT Scanners provide probably the widest range of diagnostic capabilities amongst all imaging modalities currently available. It basically creates a three dimensional reconstruction of the inside of the human body using a large series of two dimensional X-Ray images taken around a single axis of rotation. It gives us the ability to see individual body parts, be it the vessels, the heart, lungs, brain, muscles, bones etc. in detail which was never available earlier. Using complex computer algorithms, isotropic and virtual imaging has become a reality today. For example, it is setting new standards in the diagnosis and treatment of heart disease by providing a simple non-invasive alternative to the invasive angiogram performed earlier to see the condition of the blood vessels of the heart. What was the investment made by your centre in installing CT Scanners? The cost of installing a CT scanner can range from around $200,000 to a few millions depending on the type of scanner and the additional features purchased with the equipment. We currently have two of the highest-end 64 detector 500 slice/second CT scanners, two 16 slice multi-detector CT scanners and one single slice scanner. The combined investment in these machines can be estimated to be more than 2-3 million dollars. What is the current market trend of CT Scanners in India and worldwide? In India, the CT scanner is now finally

using the high-resolution imagery of the CT scanner, it is now also being used to make “made to order” or “patient specific” implants and prosthesis for surgeries which involve replacement of the joints or any other body part.

Dr Harsh Mahajan, Medical and Managing Director, Mahajan imaging centre percolating to the tier 3 and lower cities as more and more physicians are realising the benefits of using a CT scanner for diagnostic purposes. In the big cities, the trend is moving towards utilisation high-end equipment as most big hospitals and diagnostic centres are acting as referral centres for difficult cases. What are the current technology trends in CT Scanners? The applications of the CT scanner are limited only by the imagination. Currently the role of CT scanners is moving into the domain of virtual imaging wherein virtual colonoscopies, virtual bronchoscopies and more recently, virtual angioscopies are slowly becoming effective alternatives to the invasive scans which are done for the same purposes. In one of our centres, we have a research tie-up with an Indian company which has developed a CT-Guided Robotic Biopsy system to help a radiologist or a pathologist take a biopsy sample from any part of the patient with highest accuracy. Also,

The medical equipment market in India is growing at an annual rate of 15 per cent and is expected to touch $ 4.98 billion by 2012. Indian health imaging market is expected to double from the existing `1,575 crore in the next five years. X-ray, ultrasound, CT and MRI would drive this domain collectively accounting for 68.6 percent of the health imaging market. Teleradiology holds


september / 2011

What are the challenges that cropped up while implementing CT Scanners? In the early days, one of the main challenges that one faced was that of educating the physicians about the usefulness of the technology. One needs to teach along with self-assessment to make sure that what one says is being delivered. This is generally true with any new technology that we look to introduce and it is a phenomenon that is probably true throughout the world. Also, earlier the radiation exposure that was associated with CT Scanning was very high and hence we as radiologists ourselves were a little reluctant to use the technology on younger patients. What is the future of CT Scanners you see? The future of CT Scanners lies in Low Radiation Dose Imaging. There is currently, in three of our centres, a technology which greatly decreases the radiation exposure to the patient. In fact, there is a technology which is just coming out of the R&D phase, which will enable us to perform a CT scan in the same radiation dose as an X-Ray. There are many new and exciting things happening on the software side as well, which are helping acquire images with very high spatial resolution, minimising artifacts and in-turn revolutionising the diagnostic capabilities of CT Scanners.

90 percent of the market share in the country, growing at 50 percent per year. Since the days of X-ray, various technologies have exploded the radiology market. Major evolution has been noticed in the domain of CT, MRI and ultrasound, while digital radiography and teleradiology has given a whole new meaning to diagnosis.

Special Focus article

september / 2011



Special Focus

CT market is growing at a 12 percent per annum in volume terms and we expect close to 350 units to be sold in the country this year. We expect to gain market share across the segments since we are present across the spectrum. CT is witnessing growth across segments like corporate, diagnostic chains and government hospitals. Pay per use is another model to cater to the demand of the growing market. Hitachi and Trivitron is looking at these opportunities to fasten the growth and Paul Stephen, General Manager, Imaging Division, achieve its objectives. Trivitron Healthcare Pvt. Ltd. has an- Trivitron Healthcare nounced a strategic partnership with Hitachi Medical Systems to provide high end imaging solutions such as CT, MRI, Digital X-ray and Ultrasound systems. Trivitron is currently present in imaging market in India through a joint venture between Trivitron Healthcare & Hitachi Aloka Medical Ltd (ATMT) which offers Ultrasound & Color Doppler. This strategic association will enable Trivitron cater to a larger medical imaging market worth `5000 crore as against its current market coverage which is estimated at `500 crore in India in imaging segment. It will also enable Trivitron Hitachi to become market leader with over 20 percent market share over a three year period.

Cardiac Imaging Cardiologists believe that cardiac CT will become the ultimate differentiating tool for determining the treatment path for all low and intermediate-risk patients. A CT scan can reveal the overall deposition and composition of calcified and lipid-based plaque as well as stenoses. With cardiac CT angiography, there is no risk of vascular damage, heart attack or stroke; after the scan the patient can resume normal activities immediately. An ECG signal is used to gate data acquisition so that only a relatively narrow phase of the heart cycle is used for image reconstruction, the phase being selected in order to minimise motion artifacts. Since the introduction of 64-slice CT in 2006, several more-advanced models have been introduced for cardiac imaging. A 320-slice CT can capture the entire heart volume in one phase of a single heartbeat. A dual-source CT that, combined with high-pitch spiral acquisition mode, can do the same.

Refurbished Equipments There is a rampant market for old and refurbished medical devices in India that come quite cheap. The increase in medical procedures has stimulated demand for greater number of imaging equipment in hospitals. Many institutions require a second or third equipment to cope with the increasing demand for low-cost refurbished equipment as they are unable to invest in


september / 2011

new equipment due to limited funds. It is estimated that high field machines account for 12 percent share in Indian CT Scanner market. The escalating need to procure high-end but inexpensive medical imaging equipments promises further growth of refurbished medical imaging equipment market. Along with new technology in medical equipment there is an emerging trend of ‘affordable buying’, which is the basis of refurbished medical equipment business. Experts believe that buying refurbished medical equipment does not necessarily means sacrificing on quality. Buying refurbished equipment can save sometimes over 50 per cent of what you would normally pay for brand new equipment. But, there are some negative impacts of such equipments as well. Buying a discontinued product can be very risky as no parts are manufactured anymore and the customer has to depend on vendor stock or used parts from another seller or manufacturer. The buyer must understand that the most crucial aspect of a refurbished equipment vendor is his track record in the business and the quality of service support.

Future The future of molecular imaging is very promising and the hospitals and other healthcare providers will need to prepare themselves for this futuristic technology. The investments in infrastructures as well as technology are definitely worth it. PET CT scanners can be immediate actions, as this fusion of molecular imaging has already shown its unprecedented growth in cancer diagnosis and management. But there should be provisions for expansion of this into a more promising radioimmuno-based imaging and individualised therapies. Setting up small peptide synthesisers and use of positron emitter generators like 82Rb, 68Ga will prove its worth in the next five years. These are modules required for molecular imaging of gastro-neuro-endocrine tumors, cardiac perfusion and metabolic imaging. Molecular imaging (MI) will assume an ever more important role in furthering our understanding of human disease and patient care in the future. Strategic planning for investment on MI modalities is a key to success. Future in radiology will see enhanced efforts towards greater use of molecular imaging to be able to detect lesions before they attain even pinhead size and which are yet only at cellular levels. By understanding the molecular basis of disease and developing methods to detect and treat changes in the body at the molecular level, physicians will be able to identify diseases in the earliest possible stages. This will by far remain the major focus of research and development in clinical medicine in the 21st century.

eHEALTH-Sept-2011-[31-36]-Special Focus-Powering Diagnosis