by J. Moskovitz, MD
All Interventional Radiology practices strive to constantly improve their service to their patients, which includes adopting best practices from other subspecialty fields. Recently at the Florida Hospital System, we have found that products designed for neurointerventional procedures perform exceedingly well during peripheral interventions. Penumbra, Inc., is a neurovascular supply company that now creates products with peripheral vascular indications. Specifically, their guide catheters and embolic coils have changed the way physicians are able to access vascular territories, deliver therapy, and reduce procedure times.
The Penumbra Coil
The Penumbra CoilTM (Penumbra, Inc., Alameda, CA ) is a detachable, stretch-resistant, platinum embolic coil that has a volume-filling advantage compared to conventional coils (Fig 1). The Penumbra Coil 400 offers a mechanically controlled detachment, which allows physicians to deploy and retrieve 100% of the coil until correct placement is achieved. The large sizes and long lengths available (up to 32 mm x 60 cm) allow more loops to be formed by a single coil. This prohibits the coil from migrating in high flow vascular territories. Three different softness profiles allow physicians to pack an aneurysm while avoiding catheter “kick out” and maintaining smooth deployment in highly tortuous anatomy. The coil is compatible with Penumbra’s 0.025” catheters, PX400 and PXSLIM , but can be deployed through 0.025” - 0.027” microcatheters.
NeuronTM Therapy Delivery System
The Neuron™ enables more controlled delivery of therapeutics by providing improved anatomical support. This catheter has a highly flexible distal shaft, enabling improved trackability and enhanced catheter-to-vessel wall engagement at the site of therapy delivery (Fig 2). Neuron’s enhanced control is achieved by combining robust proximal support with a multi-polymer mid-shaft transitioning to a more flexible distal shaft. Neuron’s improved distal flexibility is further enhanced with hydrophilic coating to improve trackability. The Neuron family is available in three sizes with inner diameters of 0.053”, 0.070” and 0.088” to accommodate a wide variety of therapy delivery applications.
We present four cases from our clinical practice that demonstrate the utility of the Penumbra catheterization and embolization coiling systems, devices which have historically been used by neurointerventionalists. The first two cases involve embolization of gastroesophageal varices during emergent transjugular intrahepatic portosystemic shunt (TI PS) procedures. Gastroesophageal varices are significant porto-systemic collaterals that can hemorrhage, accounting for the most common lethal complication of portal hypertension, secondary to cirrhosis.
After TI PS procedures were performed in these patients, we utilized the Neuron 053 catheter to select non-decompressed varices thrugh a pre-existing delivery sheath for the TI PS. These emergency cases require embolization to stop the continuous bleeding. The Neuron 053 catheter was selected for its great trackability through tortuous vessels over a 0.035” wire, and supplied ample support for delivering coils. Typically, after these vessels are selected, the varices would be embolized using a large number of conventional coils. The large volume, long lengths, and inherent softness of the Penumbra Coils allow rapid packing of fewer coils into the available space. The combination of Neuron 053 access and efficiency of the Penumbra Coil led to decreased procedure time in these cases.
A 67-year-old man with portal hypertension secondary to cirrhosis, presented status post TIPS placement with recurrent upper gastrointestinal (UGI) bleeding from gastroesophageal
varices and failed endoscopic attempt to tamponade the bleeding. These conditions occurred despite normal patency of the TIPS and 10 mm Hg gradient through the stent. Seven Penumbra Coils (354 cm) were delivered in 7 minutes (Fig 3). Conventional embolic coils would have taken approximately three times as long to deliver.
54-year-old woman with portal hypertension secondary to cirrhosis. Patient presented for emergent TIPS for gastroesophageal variceal bleeding. Note the distal purchase of Neuron 053, allowing very easy delivery of both the PX400 microcatheter and subsequent Penumbra Coils (Fig 4).
Ovarian Vein Embolization. A 48-year-old woman, presented with 2 years of chronic pelvic pain. She was evaluated by her gynecologist and a vascular surgeon and diagnosed with pelvic congestion syndrome. Pelvic congestion syndrome is a result of varicose veins in the lower abdomen and pelvis secondary to incompetent ovarian veins. The patient had a CT scan demonstrating a dilated left ovarian vein and left sided pelvic varices (Fig 5). Traditionally, these veins are embolized with conventional “pushable” coils. This procedure can be time consuming and there is not always optimal ability to control placement of conventional embolization coils. Detachable Penumbra Coils were used (Fig 6). The large diameter and lengths allowed a faster and more accurate embolization. The softness profile gives the coil excellent packing characteristics. The catheter maintained great position and responsiveness throughout the procedure.
Hepatic chemoembolization. Chemoembolization consists of injecting embolic material along with a chemotherapy agent into the arteries that feed a tumor. Embolization of accessory vessels is often required to prevent nontarget embolization.
In this case, the Neuron 053 was utilized to inject chemotherapy agents into arteries feeding the hepatocellular carcinoma (Fig 7). After selectively cannulating the celiac artery, a Neuron 053 was advanced over a standard 0.035” guide wire. The gastroduodenal artery (GDA) was selected with a guidewire and the PX400 microcatheter, and the vessel was occluded with 3 coils. Again, we were able to create a tight pack of coils because of the softness and accuracy of the Penumbra Coil and stable catheter position from the Neuron guide catheter. Due to its microcatheter-like flexibility, Neuron 053 acted as our guide catheter, diagnostic catheter to sub-select smaller hepatic vessels, and catheter to inject chemotherapy. The versatility allowed for fewer exchanges, possibly less irritation of vessels, and a shorter procedure time.
As medicine continues to evolve, physicians must be receptive to new tools in the workplace. Neurointerventional technology holds a significant place in peripheral intervention as well. Penumbra’s unique Neuron guide catheters are more flexible distally and supportive proximally than peripheral guide catheters. The Penumbra embolization coil combines quick and efficient packing with a high degree of control. Clinically, this offers our patients a higher level of treatment and less radiation. Faster room turnover creates substantial cost savings, benefiting the patient, physician, and hospital.
Penumbra’s world headquarters is located in Alameda, CA with sales operations throughout the United States and abroad. For more information, please visit their website at www.penumbrainc.com.