Spearhead of less-invasive medicine?February 5, 2019
Interventional radiology (IR), which is emerging as a subspecialty to radiology, provides image-guided interventions to diagnose and treat diseases. Practitioners of the new discipline see the specialty at the spearhead of modern medicine, providing maximum benefit to the patient with minimal invasion.
“IRs are the real innovators in medicine, because they have found techniques to treat several tough-to-treat conditions,” says Dr Lijesh Kumar, Consultant Interventional Radiologist, PVS Memorial Hospital, Ernakulam.
“Many of the techniques practiced by cardiologists or urologists are offshoots of what IR discovered.” Making use of imaging techniques such as X-rays, MRIs, fluoroscopy, CT and ultrasounds, IRs perform a broad range of diagnostic as well as treatment procedures, including taking organ biopsies and placing stents. They can also treat tumours by inserting tiny instruments and catheters into the body via a percutaneous route. Since images are used to guide the catheters and instruments to the exact location where the procedure or treatment is to be performed, it obviates the need for open or even keyhole surgery.
IR is an innovative field where practitioners play multiple roles, comments Dr Amar Mukund, Additional Professor, Institute of Liver and Biliary Sciences, Delhi. An IR specialist may be able to block an internal bleeding simply by putting a needle directly into the bleeding site without an open surgery. Similarly, there are cases tackled by IRs where patients start bleeding post-surgery. “In fact, IRs can help bridge the gap in between… It is a subject that helps all clinicians when they are in a difficult situation where they can’t offer anything,” he explains.
From inoperable to operable
Patients with certain liver conditions are not good surgical candidates. If surgery is done on such patients, there is a high risk of complications. These patients have to be treated either with endoscopy or interventional radiology. Again, in situations where a patient has to undergo organ transplantation but cannot do the surgery immediately, IRs can offer him some treatment in the interim so that he can buy time and plan for the transplant.
Earlier, many patients had just one option — surgery. Now, IR provides multi-optional situations, prolonging the quality time of the patient.
“Many a time, IRs can make an inoperable patient operable,” says Dr Hemant Patel, president-elect, Indian Radiological & Imaging Association (IRIA). “The role of IRs will increase day by day.”
For patients referred by clinicians, IRs do interventions on the brain, interventions for the abdomen and for peripheral arteries. Unlike earlier days when catheters were the mainstay of interventional procedures, IRs currently employ a variety of devices and techniques to tackle complex anatomies like the brain. IR itself is getting further diversified into subspecialties focusing on areas like the brain or abdomen exclusively.
IR, presently, allows procedures including angioplasty, endovascular aneurysm repair, embolisations, ablations, biliary intervention, placement of central venous catheters, nephrostomy, pleural aspiration and vertebroplasty. The list of indications is likely to expand with advances in technology.
In situations where a patient is contraindicated for a surgical procedure due to a highly complicated condition, the intervention by an IR can often make a dramatic difference.
Even though percutaneous interventions usually represent a safer approach compared with traditional surgical alternatives, IR procedures can lead to iatrogenic interventional complications. Inadvertent injury to blood vessels represents one of the most common among them. Such complications can range from minor to catastrophic.
Lacking in awareness; dearth of expertise
Radiology is not restricted to simple diagnostic tests anymore. It has become more complex. Today, a CT of the abdomen can be done in a hundred different ways, opines Dr Rajendran Vilvendhan, Section Chief, Interventional Radiology, University of Boston, USA.
In US hospitals, IR is an integral part of healthcare delivery. “If IR is taken out of the Boston hospital, the hospital will collapse,” points out Dr Vilvendhan. It is part of the “decision tree”. The intervention of an IR expert helps make a risky emergency surgery into elective surgery. This happens only when there is a multi-disciplinary approach. In India, such practices are not common. There is no protocol. Patients go to different doctors and hospitals. There are so many small hospitals and many scanning centres. Scanning is a lot cheaper here. The clinicians, on the other hand, are also very “protective” of their patients. They don’t want to lose patients and revenue.
IR is also highly capital-intensive. Most of the hospitals in India are not equipped with IR departments because of the high cost of the devices. Lack of expertise is another impeding factor. Currently, the country has only a handful of well-trained IR experts. It is not the technology, but the humans that are doing the actual job. So, there’s no point in having technology without trained human resources to make use of it. Human capital is more important than technology, observes Dr Vilvendhan.
It is a fact that India is lacking in experts who can impart training in IR, concurs Dr Gireesh Warawdekar, Consultant Interventional Radiologist, Mumbai. A lot of modalities are available in bigger cities. However, there’s a lacuna as far as smaller cities are concerned. “IR is the way to go. The more IR experts are available, the better the results for the patients. It is not going to replace any other specialty,” he adds.
Despite the huge promise image-guided treatment interventions hold, the availability of such treatment facilities poses an issue. The awareness about IR is still relatively low in many regions of the world. Not just the public, but many family physicians and specialist physicians do not know the capabilities of IR and that there are many IR procedures available to help their respective patients.
Creation of awareness about IR becomes the top priority among the practitioners of this emerging subspecialty. “We want the radiologist to take up interventional radiology and spread the message that IR can really be helpful in a lot of places that people are not aware of,” says Dr Lijesh Kumar. The need to create awareness is especially greater in changing disease scenarios. There has been an exponential rise in liver diseases owing to lifestyle changes.
Towards longitudinal care
Further, there is a need for a proper referral system like multi-disciplinary board meetings in hospitals. Experts from various specialties should sit together to decide what is the best treatment course to be followed for a patient, says Dr Amar Mukund. Multi-disciplinary decision making, which is common in oncological settings, is the need of the hour, because all the specialists may not always know what is happening in other fields. ”So, if we sit together, we’ll be able to narrow down on the best tailor-made approach to the patient. Probably in difficult situations, we may give options that surgical therapy is better in a certain case, or we may feel that neither surgical nor IR is needed, only medicinal therapy will do,” he explains.
Indications are that things are gradually moving toward that direction, believe many IR experts. “There’s a slow shift towards a group interactive approach,” argues Dr Mukunthan, “and we [radiologists] need to become clinical radiologists rather than [imaging] radiologists.”
As a safe, quick, cost-effective and less invasive solution in many clinical conditions, IR holds much promise for the future. As awareness grows, IR technology should be accepted as a part of the clinical management workflow.
Furthermore, IRs are globally becoming more clinical, providing a longitudinal care model by seeing patients in the clinic before and after procedures to ensure that proper treatment has occurred. This model will provide more momentum to the subspecialty to emerge as a leader in the future.
IR clinicians feel that the technology will grow faster in the future, and that its presence should have more impact in the practice of medicine going forward.
—With inputs from Divya Choyikutty, Kochi
Embolisation An indispensable option
Embolotherapy, which is used for inoperable haemorrhage or pre-operative management of highly vascular neoplasms, has become an indispensable treatment option for a variety of conditions and an integral part of IR practice.
Radioembolisation or Selective Internal Radiation Therapy (SIRT), which combines embolisation with radiation therapy, is an endovascular treatment for primary and secondary liver tumours.
Radioembolisation has increasingly been considered as a treatment modality in the West, especially in Europe.
Data on the safety and efficacy of this procedure for the treatment of primary and secondary liver tumours is available.
In chemoembolsation, chemotherapy along with embolic agents are injected, in combination, into the tumour.
Currently, the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) is conducting a Europe-wide, prospective, observational study to gather data on transarterial chemoembolisation (TACE) using LifePearl Microspheres loaded with irinotecan (LP-IRI) in colorectal cancer (CRC) patients with liver metastatic disease.
Called CIREL (CIRSE Registry for LifePearl Microspheres), it is expected to provide more data on the appropriate use of drug-eluting beads (DEB-TACE) loaded with the chemo agent irinotecan (DEB-IRI), helping avoid unnecessary standard chemotherapy where possible. Also, the study may bring in evidence for applying TACE with drug-eluting beads earlier in the disease, besides giving some idea about the potential indications to treat patients with TACE.
Already, many clinicians in the West have started to use DEB-TACE with irinotecan to treat metastatic liver tumours. DEB-IRI is mainly considered as a palliative option for patients who have preserved liver function and performance status with unresectable chemotherapy-resistant lesions, liver metastases, beyond second-line treatment.
IRs expect that DEB-TACE has a substantial potential to become a standard treatment in metastatic colorectal cancer (mCRC), as well.
Ablating unresectable tumours
Radio Frequency Ablation (RFA) has been found highly useful in liver tumours. With the help of this outpatient procedure, clinicians can change the inoperable status of a patient to operable in many cases. Its effectiveness, however, greatly depends upon the size of the growth. “The size of the liver tumour is an important determining criterion as far the outcome of RFA is concerned,’’ said Dr S Kalpana, Professor at Barnard Institute of Radiology, Chennai, making a presentation titled “RFA for Liver Tumours” at the recent TNPY IRIA, at Chennai. According to her, RFA is a safe, cost-effective and promising option for recurrent, unresectable hepatocellular carcinoma (HCC). The procedure is more effective than other modalities in HCC.
Microwave tumour ablation provides a potentially curative treatment option for various neoplasms. Tried and tested for over 15 years, the safety and efficacy of colorectal liver metastasis (CRLM) ablation has been demonstrated in randomised trials.
The use of microwave technology can improve liver ablation outcomes. –
IR has minimally invasive solutions to many of the conditions affecting the kidneys, said Dr Mukuntharajan, head, Department of Imaging and Interventional Radiology, Meenakshi Mission Hospital & Research Centre at Madurai, deliberating on the topic “Renal Interventions” at TNPY IRIA meet.
Ablation treatment of lung tumours as an alternative to surgery and radiation treatment is growing in acceptance.
Similarly, the treatment of metastatic pulmonary disease has demonstrated good treatment outcomes. Oligometastatic treatment is also a developing option for some patients with metastatic renal cancer and prostate cancer.
Advanced interventional MR-based ablation is being tried on an experimental basis for new indications, including focally recurrent prostate cancer and for vascular malformation treatment, according to CIRSE.
In hepatic cell carcinoma (HCC), an approach combining immunotherapy with local ablative treatments is being evaluated currently.
However, large-scale studies are still needed to establish the safety of microwave ablation therapy.