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1. Central Venous Access Devices : Single-centre Experience in India
  Piyush Bafna, Sandeep J Punamiya
 

Introduction

 
Previously in the realm of surgeons, image guided insertion of central venous catheters has rapidly evolved from an infrequent event to a daily staple of many interventional radiology suites world over.
   

Application of fluoroscopy/US/CT has enabled central venous catheters to be inserted safer, faster and therefore better than in the past.

   
Radiologists have developed new techniques to manage patients with central venous occlusions and treat other catheter related complications which have become virtually non-existent.
   
Contribution of India, with such vast potential and huge patient population, in these figures being only few hundreds at only few selected centres.
 
Objective
 
We would like to describe our experience with various CVADs inserted in the radiology suite of a multi-speciality hospital in India.
 
Method
 
Over a 30 month period, 71 patients were referred for placement of CVADs for haemodialysis, chemotherapy, parenteral medications and parenteral fluids. Pre procedure assessment done by 1) PT PTT Platelets and 2) Assessment of central veins and access sites -
 
Clinical Assessment
   

Doppler

   
MRV
   
CT
   
Venography
 
Procedure
 
Puncture - Surface landmarks, Venographic guidance
   

Wire insertion under fluoroscopic guidance

   
Subcutaneous Tunnel (for tunneled catheters)
   
Sheath
   
Catheter Insertion
   
Securing Catheter
   
Dressing
 
Results
 
A total of 79 devices were inserted successfully. Early/Immediate (Air embolism, bleeding from puncture site, rhythm disorders, fracture of hub of catheter) and Late, largely related to poor nursing care, (catheter dysfunction catheter infection and accidental extrusion).
 
Conclusion
 
There is paucity of experience with radiological insertion of CVADs in India, with low referral rate and preference of surgical insertion. CVADs can be introduced safely, but requires dedicated care by the radiologist and adequate training of the nursing staff.
 
Take Home Message
 
Experience with insertion of CVAD is lacking in our country. Physician awareness, along with dedication and training of personnel involved in catheter care are necessary to establish a successful programme. If we don’t provide the service. Someone else will!
 
2. Role of Magnetic Resonance Cholangiopancreatography In Evaluation of Pancreaticobiliary System
A Prospective Study of 50 Cases
  Siddharth Jadhav, Inder Talwar
 
MRCP is a relatively new technique in MR in special imaging sequences (heavily-T2W) are utilized to depict the biliary tract, pancreatic duct and gallbladder as high signal intensity structures owing to the fluid within them.
 
Aims and Objectives
 
To define the role of MRCP in evaluation of patients with suspected pancreatico biliary disease.
   
To define the advantages and limitations of MRCP.
 
Material and Methods
 
MRCP on a 1.5 tesla intera philips MR system.
   
A random group of first 50 patients referred for MRCP were selected for the study.
 
Patient Preparation
 
Fasting ~ 6 hrs, preferably overnight
   
Breath holding instructions
 
Observations
 
Indications
   
  Epigastric pain - 50%
  Jaundice - 24%
  Epigastric pain and Jaundice - 14%
  Others - 12%
     
MRCP Findings
     
  Cholelithiasis - 14 pts.
  Ductal anomalies - 13 pts.
  Pancreatitis - 12 pts
  Cholangiocarcinomas - 09 pts.
  Benign stricture - 06 pts.
  Choledocholithiasis - 05 pts.
  Pancreatic neoplasm - 01 pts.
     
Others (Hydatid cyst etc.)
 
Failed or suboptimal MRCP
 
2 cases - 1 paediatric patient and 1 due to gross ascites
 
2 false negatives
 
GB Calculus in one patient (< 2 mm) missed.
   
Was picked at USG
 
Hepatic metastasis in a case of Cholangio-carcinoma was missed which was picked on contrast CT (Routine use of Gadolinium would have picked the lesion)
 
Advantages of MRCP
 
MRCP is
 
Noninvasive
   
Well accepted and tolerated by patients
   
Technically operator independent
   
Low failure rate.
 
True Advantages of MRCP v/s ERCP
 
High grade obstruction - demonstrates proximal and distal biliary tree which neither PTC nor ERCP can without risk of infection.

Concomitant staging of the obstructing neoplasm.

Failed ERCP due to failed cannulations or altered anatomy (gastric outlet obst, duod stenosis, Roux en Y loop and hepaticojejunostomy), poor candidates due to cervical fractures etc.
 
MRCP avoids complication of ERCP of which are
 
Pancreatitis (3-5%)
   
Sepsis
   
Perforation
   
Haemorrhage
 
MRCP - Pitfalls / Limitations
 
Limited spatial resolution
   
Biliary leaks
   
Imaging artifacts
   
Underestimation of duct caliber as compared to ERCP - physiologic state versus distended ducts at ERCP
   
Purely diagnostic
 
3. Distal Protection During Renal Angioplasty
  Piyush Bafna, Sundeep Punamiya
 
Atheroembolism to the kidney is a well-established but poorly recognized phenomenon that tends to occur in patients with severe atherosclerosis affecting the aorta and renal arteries. This phenomenon occurs when plaques emitting cholesterol particles shower them into the renal parenchyma, mechanically blocking intra renal vessels, at the arcuate and interlobar level. In addition, these crystals induce a local foreign body response, and interlobar level. In addition, these crystals induce a local foreign body response, and interlobar level. In addition, these crystals induce a local foreign body response, leading to progressive fibrosis of the vessel, and further reducing its lumen. Plaque dissemination could be provoked by mechanical trauma during angiography, angioplasty or vascular surgery, having more acute consequences. This was well established in post-mortem and laboratory analyses. Thurlbeck and Castleman demonstrated an incidence of renal atheroembolism in > 20% in severely atherosclerotic aortic disease, with the incidence spiraling to > 70% following AAA surgery. Flory demonstrated that the emboli were cholesterol crystals occluding vessels between 55-900 microns. Kimura et al experimentally showed that the effects of embolism were dose dependent; larger showers of cholesterol emboli are more susceptible to cause renal shutdown.

It is well known that angioplasty procedures are likely to produce distal embolism. Rapp et al, in an ex vivo study of carotid angioplasty, showed that initial passage of guide wire produced emboli, but there was a significant increase during angioplasty and even more so during stent placement. Microemboli were also detected in vivo with transcranial Doppler during carotid angioplasty, having a definite spatial relationship between Doppler recognition of emboli and neurological sequelae.

There are, however, no data on renal artery Doppler recognition of emboli during intervention. Al-Hamili et al reported remarkable findings in patients undergoing iliac angioplasty. These authors recorded Doppler signals during renal angioplasty. Interestingly, signals (although low) were recorded in the femoral arteries for 2h after renal angioplasty. Imagine what the Doppler signals in the renal arteries would have reflected during renal revascularisation.

Devices were evolved to protect the distal circulation from the derogatory effects of emboli during angioplasty. They were initially used in the treatment of patients with coronary bypass graft disease; these interventions were commonly plagued by the angiographic “no reflow” phenomenon, producing clinical myocardial infarction. Use of protection devices produced significant reduction in mortality, myocardial infarction and need of emergency CABG in such patients. Similarly, better outcome was noted during carotid angioplasty when filters were used. Not surprisingly, debris was detected in 91% of coronary filters and in 84% of carotid filters following revascularisation.

The results of coronary and carotid angioplasty can be easily extrapolated in predicting outcome of renal interventions, as the atheromatous pathology and patient population are similar. Atheroembolism has long been viewed as a major risk or complication of percutaneous intervention of the renal arteries. Most studies of endovascular revascularisation in ischaemic nephropathy have reported procedure-related acute decline in renal function of 10-20% patients, largely related to cholesterol embolisation. It is important to recognize that the large functional reserve would not allow SCr to get elevated until as much as 50% of total glomerular filtration is lost. Large volume of debris would then be required to create any significant functional alteration of the kidney. However, once the SCr becomes abnormal, the curve relating GFR to SCr becomes abnormal. Small amount of renal debris can then have a dramatic outcome in deteriorating the renal function. Which makes it imperative to protect the kidney from any amount of debris blocking its arteries.

The ideal device should have the property to capture all debris, regardless of size. It should allow continued renal perfusion during the procedure, have limitless reservoir and have good technical qualities such as low profile with least vascular trauma, good trackability, easy to use and recapture. Compared with other devices, the renal device should have particular qualities; the filter length should be short for adequate renal protection. Also, the wire should be stronger to allow stent trackability at severe angulations of the renal artery take-off. Currently, there are two types of devices that could be used in renal interventions: filter devices and occlusion devices, both of which have its advantages and drawbacks.

The experience with distal protection in renal interventions has been early, with only two publications to date. Michel Henry et al had studied 28 patients (32 renal arteries) using an occlusion device. All patients had none or mild renal dysfunction. He noted visible debris in all cases, while no patient showed worsening of renal function in the 6m follow up. Another study by Holden and Hill involved the use of a filter device in 37 patients (46 arteries), all of which had some degree of pre-existing renal impairment. In this patient group, 65% of the devices contained significant debris. All patients having mild or moderate renal impairment had improvement or stabilization of renal function, whilst 5% of the patients (from the severe renal impairment group), had unchanged decline in renal function. When compared with results from the same institute without use of protection, there is a substantial benefit of usage of these devices. Our experience at Bombay Hospital is with 11 arteries in 8 patients using occlusion and filter devices. All showed stabilization/improvement in SCr levels with a mean follow up of 6 months.

While these studies are case-controlled, it would be essential to really understand the value of these devices in a randomized trial. At present there is an ongoing trial (Resist trial), the results of which are awaited. Until then, we would believe that distal protection should be offered in all patients with renal impairment, especially in those with a solitary functioning kidney, severe atherosclerosis, or when bilateral renal angioplasty is being considered.
 
4. Tips Reduction
  Piyush Bafna, Sundeep J Punamiya
 

Transjugular intrahepatic portosystemic shunt (TIPS) is porto-systemic shunt created within the liver parenchyma.

It is done by deploying a stent in the liver, connecting the portal vein and hepatic vein. Indications include uncontrolled bleeding, recurrent bleeding, ectopic bleeding (anorectal, intestinal, stomal and caput medusae), portal hypertensive gastroenteropathy, ascites (refractory/intolerant to medical therapy), hepatic hydrothorax (refractory/intolerant to medical therapy), Budd-Chiari syndrome, mesenteric/portal venous thrombosis, hepatorenal syndrome, hepatopulmonary syndrome and chylous ascites and chylothorax.

 
Results
 
Procedural success is 95-100%
 
  ? Failures in PVT, BCS, paeds
 
Procedural mortality is <1%
 
  ? Trauma, intra abdominal bleeding
 
1 month mortality is 3-44%
 
  ? Poor liver function
     
  ? Emergency TIPS
 
Excellent resolution of ascites - 100% with improvement in liver function.

Control of variceal bleeding - 81-96%

Ascites - 80% resolution @ 6m

Hepatic hydrothorax - 60% relief
 
Complications
 
  Durability
   
  Encephalopathy
   
  Liver failure and death
   
  Encephalopathy is reported in 5-35% of TIPS patients, managed conservatively in majority. Incidence of refractory encephalopathy is 3-7%.
   
  Requires endovascular treatment by occluding or reducing TIPS which can be done by constraining using prolene suture, balloon expandable stent and stent graft.
   
  Drawbacks include potential for variceal bleeding or haemodynamic alterations which can be fatal.
 
Conclusions
 
TIPS is effective in treating intractable complications of portal hypertension.
   
The longetivity of stent-grafts has almost resolved the problem of restenosis.
   
Encephalopathy cannot always be predicted, but if present, can be easily managed by reduction of shunt diameter.
   
Selection of cases is paramount for a successful TIPS programme.