bluuebunny/crossref_metadata_2025 huggingface dataset:
Using a Glidewire Cheater and Flow Switch to Temporarily Secure Purse-String Sutures
Authors: Plotnik Adam N. , Kee Stephen
Published: August 2018

Following completion of an arteriovenous graft or fistula intervention, various methods exist by which an interventionalist may achieve hemostasis. Manual compression is the simplest technique but often requires an extended period of time. Many interventionalists will place purse-string sutures at the site of vascular access to achieve hemostasis, with the sutures left in place when the patient leaves the angiography suite. Consequently, these sutures may stay in for an extended period of time and even be present at follow-up interventions many months later or, worse, may get infected. The glidewire cheater and flow switch technique is a method by which hemostasis can be achieved, and it obviates the need for the sutures to be left in place after the patient leaves the angiography suite.
Deploying a Straight Conical Filter
Authors: Kahn S. Lowell
Published: August 2018

Placement of inferior vena cava (IVC) filters is among the most common medical procedures, with more than 265,000 placed annually. Absolute indications for their placement include acute proximal deep venous thrombosis (DVT) and pulmonary embolism (PE) in patients who have an absolute contraindication to anticoagulation and patients with recurrent thromboembolism despite adequate anticoagulation. Although the survival benefit is unknown, it has been shown that filters decrease the incidence of PE in the short term. Unfortunately, this comes at the expense of known complications, the most important being DVT. This chapter discusses simple techniques to prevent conical filter tilting and enhance retrieval.
Removing the Angled Inferior Vena Cava Filter with an Embedded Hook: The “Hangman” Technique
Authors: Plotnik Adam N. , Kee Stephen
Published: August 2018

Multiple advanced techniques for the retrieval of difficult inferior vena cava (IVC) filters have been published in the literature, most of which describe mechanical methods to disrupt the fibrous capsule in cases in which the filter hook or struts have become embedded in the IVC wall. Despite reported high success rates, these techniques often require multiple venous access sites or the use of special equipment. The “hangman” technique is a modified “loop snare” technique that requires only a single venous access and uses standard interventional equipment. It modifies the loop snare technique by passing the wire loop between the filter neck and IVC wall, as opposed to the filter. This chapter elaborates on the hangman technique and its applications and steps.
Femoral Flip Technique for Removal of the G2 Filter
Authors: Plotnik Adam N. , Kee Stephen
Published: August 2018

The purpose of temporary retrievable inferior vena cava (IVC) filters is to provide protection from pulmonary emboli while the patient is at risk while simultaneously avoiding the long-term complications that result from permanent filters. In addition to the complications of filter fracture and caval penetration, there is an increasing incidence of recurrent deep vein thrombosis and caval occlusion following filter placement; therefore, whenever possible, retrieval of IVC filters should be attempted. The “femoral flip” technique may be employed for difficult G2 IVC filter retrievals where standard techniques have failed, usually due to either one of the legs or the hook becoming embedded in the wall.
Laser Sheath Assisted Filter Removal
Authors: Arabi Mohammad
Published: August 2018

This chapter presents a step-by-step guide to the use of laser sheath assisted filter removal. It describes the clinical applications of laser-tipped sheath in removing chronically embedded filters using controlled photothermal ablation of the endothelium surrounding the filter struts. This technique has been long used for extraction of pacemaker leads and has recently been extrapolated to filter removal because it minimizes the forces applied during difficult retrieval procedures and allows for removal of permanent filter devices. In addition to requiring less force for filter retrieval, laser sheath assisted removal helps reduce the total fluoroscopic time needed to complete the procedure. This chapter details the technical steps, potential pitfalls, and possible complications of this technique.
Slow and Steady Method for Advancing Devices Through Tight or Tortuous Anatomy
Authors: Heithaus Robert Evans , Syed Almas , Rees Chet R.
Published: August 2018

Advancing vascular sheaths, catheters, balloons, stent grafts, or drainage catheters can prove difficult in tight or tortuous anatomy, leading to prolonged procedure and fluoroscopy time. Overcoming the static forces of friction requires greater magnitude of force compared to the kinetic forces of friction. Static forces of friction can result in catheter or device kinking, particularly in tight or tortuous anatomy. By applying slow, steady force (as opposed to multiple isolated applications of force) in a manner described in this chapter, one can advance a device in a slow and steady manner, thus reducing the amount of pain, tissue damage, and potentially fluoroscopy time.
End of the Road: Bailout Techniques for the Short Wire
Authors: Kahn S. Lowell
Published: August 2018

Guidewires for peripheral interventions come in a variety of lengths for the 0.035/0.038-, 0.018-, and 0.014-in. platforms. Common lengths include 75/80, 145, 180, 200, 260, 300, and 330 cm. Whereas a navigation wire needs only to be slightly longer than the catheter in use, guidewires over which exchanges are necessary for intervention need to be considerably longer. As a general rule, a guidewire should be long enough to be passed sufficiently beyond the treatment zone (e.g., occlusion) to facilitate adequate support with enough wire external to the patient to allow for any desired catheter or balloon use/exchange (e.g., 150 cm for a typical tibial balloon). This chapter elaborates on techniques to overcome a short wire obstacle during procedures.
Balloon Anchor Techniques for Sheath, Guide Catheter, and Stent Advancement and to Facilitate Chronic Total Occlusion Traversal
Authors: Kahn S. Lowell
Published: August 2018

Advancement of a sheath or guide catheter into a small, diseased or angled branch vessel such as the superior mesenteric artery or renal artery can be difficult. Similarly, there are times when placement of a sheath up and over a sharply angulated aortic bifurcation can present a challenge. Obtaining a sheath position at or beyond a stenotic or occlusive lesion may be critical for delivering a stent, particularly with the inherent risk of dislodgment associated with balloon-expandable stents. The use of balloons as anchors has been described most commonly in the coronary vasculature, but it can have an important role in peripheral and visceral applications. This chapter discusses the utility of balloons as an anchor to advance a sheath or stent to a target location.
Catheter Modification Techniques for Venous Sampling
Authors: Kahn S. Lowell
Published: August 2018

Venous sampling is critically important in the diagnosis and localization of pituitary, parathyroid, renal, adrenal, and ovarian endocrine tumors and conditions. Catheterization of smaller veins can present a challenge and may be responsible for technical failures, particularly with adrenal vein, parathyroid, and inferior petrosal sinus venous sampling. Beyond the inherent challenges of catheterization posed by small veins, obtaining adequate blood samples can be difficult because the return of blood from a small vein may be exceedingly slow. This chapter discusses techniques to enhance the return of venous blood flow from a diagnostic catheter in a small vein. These techniques are applicable to all venous sampling, but they are particularly beneficial when sampling small-caliber veins.
Clearing the Clogged Microcatheter During Particulate Embolization
Authors: Parikh Roshni A. , Williams David M.
Published: August 2018

This chapter describes the steps in management, applications, challenges, and potential complications when a microcatheter becomes clogged during an embolization. If a microcatheter does become occluded during an embolization, it can be a challenge to clear it without removing the catheter completely, thus losing access to the desired location. If a standard 1-cc syringe is placed and manual pressure is applied to clear the catheter, this can generate pressures up to 100 times the arterial blood pressure, thus risking nontarget embolization from the residual embolic material in the microcatheter. This chapter describes the steps involved in safely clearing an occluded microcatheter with the use of a standard balloon insufflator.
The Anchor and Scaffold Techniques for Precise Coil Embolization
Authors: Kahn S. Lowell
Published: August 2018

Deploying coils accurately in high-flow vessels can be challenging. Particularly with larger vessels, obtaining the stability to prevent downstream coil migration is of paramount importance. This is particularly true in the embolization of pulmonary arteriovenous malformations, in which distal coil migration to the systemic circulation can have disastrous consequences. Although detachable coils/balloons, hydrocoils, and plugs mitigate some of this risk, these devices are costly and not always readily available. Furthermore, there are times when a large plug may not be deliverable to the intended target, necessitating use of coils instead. This chapter describes two separate techniques to secure coils at their site of deployment—the anchor technique and the scaffold technique.
Selective Retrograde Thoracic Duct Embolization
Authors: Masrani Abdulrahman , Arslan Bulent
Published: August 2018

Thoracic duct injury is potential complication of neck surgeries, especially surgeries that include neck dissection. It can present as a lymphatic drainage at the wound site, chylous fistula, chylothorax, chylomediastinum, chylopericardium, lymphocele, persistent lymphorrhea, or secondary lymphedema. This complication is managed with intraoperative repair of the injury if recognized, conservative measures of dietary changes and octeriotide, thoracic duct embolization by interventional radiology, or surgical re-exploration of the wound with repair of the injury. This chapter describes a technique to selectively embolize the injured lymphatic branch of the thoracic duct utilizing coils and Onyx instead of embolizing the main duct. This technique eliminates the need for nodal or pedal lymphogram and thus saves time, effort, and reduces expense.
Water Seal Technique for Lung Biopsy
Authors: Narsinh Kazim , Kinney Thomas
Published: August 2018

Gas embolism is an infrequent but potentially severe complication of percutaneous transthoracic lung biopsy. One potential mechanism for the creation of an arterial gas embolism is the introduction of atmospheric air into the biopsy needle when the tip is located in the pulmonary vein. To minimize the risk of introducing air into a pulmonary vein via the biopsy needle, a “water seal technique” can be used to create a hydrostatic column within the introducer needle before the biopsy needle is inserted. Then, if sufficient negative intrathoracic pressure is generated while the needle tip is in a pulmonary vein, saline will enter the pulmonary vein rather than air. This chapter describes the water seal technique to mitigate the risk of arterial gas embolism during transthoracic lung biopsy.
Extreme Thoracic Biopsies
Authors: Derry William , Genshaft Scott
Published: August 2018

Percutaneous transthoracic biopsy is a commonly used procedure in the diagnosis of intrathoracic pathology. With modern imaging and interventional devices, percutaneous transthoracic biopsy allows access to locations inaccessible by mediastinoscopy or bronchoscopic biopsy. This chapter presents tips for performing successful percutaneous biopsy of lesions in precarious intrathoracic locations. The practices highlighted should help maximize the chances for a successful tissue yield while minimizing the rate of biopsy-associated complications. Mediastinal, hilar, and juxtapleural lesions present anatomic challenges that can decrease the chance of safely obtaining tissue and increase complication rates. The use of techniques to displace injury-prone anatomical structures and to open access windows can allow the interventionalist to obtain diagnostic tissue samples from almost all intrathoracic locations. A well-planned approach is the most important factor in maximizing yield and preventing complications.
Balloon Occlusion Technique During Y90 Radioembolization
Authors: Mahvash Armeen , Murthy Ravi
Published: August 2018

The conventional technique for 90Y microsphere treatment planning involves diagnostic angiography with prophylactic embolization of hepatoenteric collaterals to prevent non-target microsphere administration. In some instances, embolization is not technically feasible due to anatomy or the size of the collateral vessel. In lieu of prophylactic embolization, the balloon occlusion technique may be employed. The technique uses a compliant balloon to temporarily occlude the common hepatic artery to induce reversal of arterial flow in various hepatoenteric collaterals (gastroduodenal, right gastric, supraduodenal, etc.). This technique is generally employed in patients with Michaels type 1 anatomy; however, it can also be used in patients with variant anatomy.
Percutaneous Thermal Ablation: Hydrodissection and Balloon Displacement to Protect Adjacent Non-Target Critical Structures
Authors: Wolf Farrah J. , Iannuccilli Jason
Published: August 2018

This chapter describes techniques that may be utilized to protect soft tissue structures and vessels that lie less than 1 cm from the planned ablation zone from thermal injury. Hydrodissection with dextrose 5% in water combined with non-ionic contrast material may be used as a means of providing mechanical displacement. Alternatively, an angioplasty balloon inflated with air may be used to provide both physical displacement and thermal insulation. This chapter provides an overview of the percutaneous image-guided thermal ablation technique as well as clinical examples, including microwave ablation of a renal cell carcinoma and radiofrequency ablation of a hepatocellular carcinoma, utilizing hydrodissection and balloon displacement techniques.
Bland Lipiodol-Assisted Thermal Ablation of Renal Cell Carcinoma
Authors: Kahn S. Lowell
Published: August 2018

Surgical resection of renal cell carcinoma (RCC) remains the standard of care given the excellent reported outcomes for early stage disease, with 5-year cancer-specific survival (CSS) rates of 97% for pT1a and 87% for pT1b tumors after nephrectomy. Outcomes after partial nephrectomy are equally encouraging, with 5- and 10-year CSS rates of 92% and 80%, respectively, across all stages and 96% and 90%, respectively, for tumors less than 4 cm. Transarterial embolization prior to thermal ablation for RCC is far less frequent, but it is described in the literature. To date, there are no randomized controlled studies that demonstrate a benefit of combined therapy over radiofrequency ablation (RFA) or cryoablation alone. However, lipiodol is profoundly radiopaque, and utilization prior to RFA or cryoablation may aid in the visualization of the tumor.
Optimal Imaging Techniques of the Portal Vasculature During TIPS Creation: Use of the CO2 Portogram
Authors: Ferral Hector
Published: August 2018

Transjugular intrahepatic portosystemic shunt creation is one of the most complex interventional procedures. It requires skills in imaging, vessel catheterization, guidewire techniques, balloon angioplasty, endovascular stent deployment, and embolization techniques. The key step during this procedure is obtaining access into the portal vein. This chapter discusses how to perform a CO2 portogram to obtain access to the portal vein during the creation of a transjugular intrahepatic portosystemic shunt (TIPS). The CO2 portogram may be performed with an angiographic catheter wedged in the hepatic vein, with an occlusion balloon inflated within the hepatic vein, or with the transhepatic needle within the liver parenchyma—the so-called “intraparenchymal” injection. Those performing a CO2 portogram should have knowledge of CO2 and a user-friendly CO2 delivery system to avoid common CO2 complications.
Use of Prolapsing Guidewire to Secure Portal Venous Access During the TIPS Procedure
Authors: Kinney Thomas , Narsinh Kazim
Published: August 2018

Perhaps the most critical portion of the transjugular intrahepatic portosystemic shunt procedure involves obtaining secure portal venous access. An acute angle of entry into the portal venous system during intrahepatic portosystemic shunt creation can make retrograde advancement of a guidewire into the splenic or superior mesenteric vein difficult. However, securing access from the jugular access site to the portal system with a reliable guidewire is of critical importance during the procedure. This chapter presents a technique to advance a flexible-tip guidewire antegrade into right portal vein branches prior to prolapsing the guidewire into the main portal vein to secure transjugular portal venous access.
Advancing the TIPS Sheath Through a Difficult Cirrhotic Liver: Pay It Forward Off the Balloon
Authors: Plotnik Adam N. , Kee Stephen
Published: August 2018

The “pay it forward off the balloon” technique for advancing the transjugular intrahepatic portosystemic shunt (TIPS) sheath may be employed during a difficult TIPS case when the interventionalist has already accessed the portal vein but cannot get the standard 10 Fr TIPS sheath through the fibrotic tract into the portal vein to thereby allow placement of a standard TIPS covered stent. In some patients, the fibrotic recoil of the parenchymal hepatic tract can be so severe that the basic balloon dilation maneuver fails. The pay it forward off the balloon technique employs the use of a 6 mm × 4-cm balloon, which is placed through the 10 Fr TIPS sheath and advanced over the wire and across the fibrotic tract into the portal vein.
Deployment of Direct Intrahepatic Portocaval Shunt (DIPS) from a Femoral Access
Authors: Masrani Abdulrahman , Arslan Bulent
Published: August 2018

The transjugular intrahepatic portosystemic shunt (TIPS) has been shown to be effective in management of esophageal varices bleeding in patients with liver cirrhosis when endoscopic manuvers fail to control it. Ascites refractory to optimal medical therapy is another indication for TIPS procedure. Occasionally, TIPS cannot be performed due to vascular anatomical difficulties such as occluded central venous access, small hepatic veins, or portal vein occlusion. Direct intrahepatic portocaval shunt (DIPS) can be considered as an alternative option in such circumstances. DIPS is typically performed utilizing jugular access with direct puncture from the inferior vena cava (IVC) to the right portal vein. However, the interventionalist may be challenged by jugular or brachiocephalic veins occlusion. This chapter discusses perfroming DIPS procedure utilizing femoral access in a patient with bilateral occluded brachiocephalic veins and thrombosed right portal vein.
Transmesenteric Method of TIPS Placement Using Portal Access via Mini-Laparotomy
Authors: McCabe Sam , Harnain Christopher , Rozenblit Grigory
Published: August 2018

Transmesenteric portal access via mini-laparotomy may be used as a salvage technique when standard transjugular intrahepatic portosystemic shunt (TIPS) is unsuccessful due to difficult anatomy or portal vein thrombosis. This technique allows for precise determination of both the portal and the hepatic vein branch involved in the TIPS. This method usually involves the cooperation of a surgeon, who performs a mini-laparotomy and exposes a small bowel loop in the interventional suite. A mesenteric venous branch is then cannulated, providing direct access to the portal venous system. In distinction to standard technique, the hepatic parenchymal tract is created by a puncture from the portal vein into the hepatic vein. A guidewire advanced through the puncture needle is then snared from the hepatic vein, providing through-and-through access. The TIPS can be completed using standard techniques. Upon completion, the mini-laparotomy is closed by the surgeon.
Recanalization of Occluded TIPS Using a Transhepatic Percutaneous Technique
Authors: Sabri Saher S.
Published: August 2018

Transjugular intrahepatic portosystemic shunt (TIPS) dysfunction rates have significantly decreased since the introduction of stent grafts. However, TIPS occlusion remains a recognized complication, especially when bare-metal stents are used or when the cephalad end of the stent does not extend into the inferior vena cava (IVC). Antegrade recanalization of the occluded TIPS can be routinely achieved using a coaxial or a triaxial sheath system, which provides sufficient stability and pushability to recanalize the TIPS. However, occasionally this cannot be achieved due to the difficult angulation between the IVC and the hepatic vein, poor placement of the initial TIPS short of the IVC, or long-standing occlusion of the TIPS. Retrograde recanalization of the TIPS by transhepatic percutaneous access of the TIPS using a 21 gauge needle can be performed in such situations.
Adjustable Small-Diameter TIPS
Authors: Irani Zubin , Zhao Sara
Published: August 2018

Transjugular intrahepatic portosystemic shunt (TIPS) was first described by Rosch et al. in 1969, and in 1982, Colopinto et al. described its first clinical application in a patient with cirrhosis and variceal hemorrhage. It was not until 1988 that the first metal-lined shunt was created, and in 1997 the first polytetrafluoroethylene (PTFE)-lined stent was used in humans for shunt revision after stenosis, created by pinning the Gore PTFE graft material between two metal stents. Introduced in 2000, the Viatorr stent graft is now the most commonly used device for TIPS. One of the major side effects of TIPS creation is hepatic encephalopathy (HE). This chapter discusses the adjustable small-diameter transjugular intrahepatic portosystemic shunt.
Use of a Coda Balloon to Assist Left Renal Vein Sheath Delivery During Balloon-Occluded Retrograde Transvenous Obliteration
Authors: Kahn S. Lowell
Published: August 2018

Fundamental to all balloon-occluded retrograde transvenous obliteration procedures is the catheterization of the gastric varix via its drainage through a gastrorenal shunt and its subsequent sclerosis. Although routinely performed with little difficulty in experienced hands, there exist clinical scenarios and anatomic factors that present technical challenges to the procedure. A common challenge is the delivery of the occlusion balloon to the neck of the gastrorenal shunt to allow occlusion. Two main factors affect this: the angulation of the veins relative to one another and the size of the balloon required to achieve occlusion. This chapter describes a technique to facilitate delivery of a sheath to the left renal vein from a femoral approach when the caudal angulation of the left renal vein makes catheterization unfavorable.
Use of Contrast-Fortified Surgilube for Biliary Drainage in the Setting of Active Leakage
Authors: Kahn S. Lowell
Published: August 2018

Biliary leaks are a common clinical entity that may occur after trauma or surgery. Endoscopic retrograde cholangiopancreatography (ERCP) is the first choice of treatment for an active biliary leak. Percutaneous transhepatic cholangiography (PTC) with drain placement (external or internal/external) is increasingly employed either alone or as an adjunct to endoscopy (Rendezvous procedure) or surgery. Performance of a PTC on the nondilated system remains technically challenging and is associated with extra needle passes and significantly longer fluoroscopy times. Technical challenges arise from needle localization of a small nondilated duct and the contrast that is injected will pass through the leak rather than distending and opacifying the ducts. This chapter describes the use of contrast-fortified Surgilube for biliary opacification in the setting of an active biliary leak.
Percutaneous Placement of a Temporary Large-Bore Biliary Endoprosthesis
Authors: McCabe Sam , Harnain Christopher , Rozenblit Grigory
Published: August 2018

This chapter describes construction of a temporary large-bore biliary endoprosthesis from a standard pigtail drainage catheter. Management of benign common duct biliary strictures often requires multiple interventions and leaves the patient with an indwelling biliary catheter for a prolonged time course. Commercially available plastic, bare-metal, and covered metal biliary stents are not ideally suited for the management of benign strictures. The endoprosthesis is cut to length and then positioned, deployed, and tethered to the abdominal wall with an absorbable suture. After the suture dissolves in several months, the catheter is propelled into the intestine by peristalsis and expelled without the need for an additional procedure.
Method of Increasing Luminal Scaffolding for Biliary Strictures
Authors: Kahn S. Lowell
Published: August 2018

Benign biliary strictures are a common clinical entity encountered by the interventionalist. Balloon dilatation is an acceptable modality of treatment, but restenosis is frequent. The recoil that follows balloon dilatation of recalcitrant benign biliary strictures presents a treatment challenge. This chapter presents a single-access dual-drainage catheter technique that has been employed successfully for more than 6 years. The procedure involves the standard placement of a large drainage catheter (ideally 14 Fr) across the biliary stricture. A second catheter measuring between 5 and 8.5 Fr is advanced through the hub of the 14 Fr drainage catheter and subsequently exits through a proximal hole of the 14 Fr drainage catheter. At the site of the stricture, there is side-by-side placement of the two drainage catheters providing extra scaffolding despite the 14 Fr percutaneous tract.
Use of a Fogarty Balloon Catheter to Create Backwall Support and Facilitate Intrahepatic Bile Duct Access During Antegrade Stone Extraction
Authors: Carberry George , Ozkan Orhan
Published: August 2018

Percutaneous transhepatic stone removal may be indicated in patients with altered upper gastrointestinal anatomy precluding use of endoscopic stone extraction. When biliary calculi are located in a duct adjacent to the duct cannulated percutaneously, obtaining wire and catheter access into the target duct may be difficult due to the acute angles required of the wire and catheter to access the stone-containing duct. One useful method described and illustrated in this chapter to address this issue involves inflating a balloon catheter downstream from the origin of the target duct to deflect a wire into the target duct and to provide backwall support at the apex of the wire for advancement of the stiff balloon catheter. Once the duct containing the biliary calculi is accessed, sweeps of the calculi can be performed.
Portal Vein Tract Embolization After Percutaneous Transhepatic Biliary Interventions
Authors: Narsinh Kazim , Rose Steven C. , Kinney Thomas
Published: August 2018

Bleeding complications during percutaneous biliary intervention result from injury to the hepatic artery, hepatic vein, or portal vein. If bleeding originating from a hepatic artery branch is suspected, hepatic arteriography should be performed with and without the drainage catheter in place over a wire, and subselective embolization can be performed if a suitable target is identified. If a bleeding hepatic artery branch is not identified, bleeding from a portal vein branch is suspected. Treatment of portal vein injuries is challenging in this situation because obtaining direct percutaneous portal vein access is ill-advised. Although injuries to the hepatic artery or vein can often be treated by tract tamponade or arterial embolization, iatrogenic communication between the portal vein and biliary system can be difficult to treat effectively. This chapter presents a method to identify portal vein-to-biliary tract communications via cholangiography, with subsequent embolization via the transhepatic tract.
Use of an Elongated Radiopaque Gelatin Sponge Plug for Tract Occlusion After Hepatic Interventions
Authors: McCabe Sam , Harnain Christopher , Rozenblit Grigory
Published: August 2018

This chapter describes the use of an elongated radiopaque gelatin sponge plug for tract occlusion after percutaneous biliary, portal venous, or hepatic venous access or intervention. Often, embolization coils or a gelatin sponge “slurry” is sufficient for hemostasis following liver intervention. This technique offers an inexpensive, temporary, and readily available option for achieving hemostasis following liver interventions. A contrast-soaked Gelfoam plug is loaded into a delivery cylinder that is advanced into the access sheath and positioned and deployed under fluoroscopic guidance. This technique is an alternative option to the use of embolization coils or a gelatin sponge slurry when seeking hepatic parenchymal tract hemostasis following intervention.
The Air Technique to Determine Appropriate Posterior Calyx for Puncture
Authors: Narsinh Kazim , Kinney Thomas
Published: August 2018

A posterior calyx is the preferred point of entry into the urinary collecting system during percutaneous nephrostomy procedures. Although ultrasonographic guidance is the preferred modality to gain this initial access, confident identification of a posterior calyx can be challenging using sonography alone, particularly in obese patients without hydronephrosis. In this setting, air or carbon dioxide can be introduced into the prone patient’s collecting system in order to fluoroscopically guide a confident puncture of the posterior calyx of the renal collecting system. This chapter presents a technique employing the introduction of air into the urinary collecting system to permit facile identification of a posterior calyx using fluoroscopic guidance during percutaneous nephrostomy procedures.
Permanent Ureteral Occlusion
Authors: Justaniah Almamoon I.
Published: August 2018

Distal ureteral injuries are uncommon. When present, urine leakage may ensue. Common etiologies are gynecologic surgeries (75%), trauma, pelvic malignancy, and radiation therapy. Clinical presentation varies according to the location of leakage or fistula. For example, patients with ureterovaginal fistula may present with vaginal discharge. Patients with intra-abdominal leakage may develop urinoma or abscess. Unfortunately, most of these patients are poor surgical candidates due to prior surgery and/or radiation. Therefore, operative repair can be challenging and at times not a valid option. Transrenal ureteral occlusion may provide the best available option for such patients. A trial of urine diversion via percutaneous nephrostomy tube may allow spontaneous healing. If this fails, ureteral occlusion proximal to the leak/fistula can be attempted with a success rate up to 100%. Occlusion techniques include ureteral clipping, radiofrequency cauterization, embolization coils, Amplatzer vascular plugs, detachable balloons, absolute alcohol, and isobutyl-2-cyanoacrylate (glue).
Exchange of Retrograde Occluded Nephroureteral Catheter Through Ileal Conduits Without Losing Access
Authors: Soni Jayesh M.
Published: August 2018

A retrograde nephroureteral catheter is placed in patients who have undergone cystectomy with ileal conduit formation. An ileal conduit connects the ureters to a loop of bowel that is then secured to the anterior abdominal wall to allow for ostomy bag drainage. Patients may develop complications in the form of stricture at the ureteroenteric junction causing obstruction. These patients may need temporary diversion of urine through a nephrostomy catheter. The retrograde nephroureteral catheter is a better option because it provides a less invasive and safer approach. Unlike the routine exchange of a nephroureteral catheter over the wire through the ileal conduit, wire access through the catheter to the renal pelvis is sometimes difficult or impossible due to encrustation with calcium deposition, catheter fracture, and catheter migration. Alternative techniques to avoid these complications include the use of a parallel glidewire or use of a larger sheath over the catheter or the catheter snare.
Use of a Mushroom-Retained Gastrostomy Tube for Stenting Benign Esophageal Stricture
Authors: McCabe Sam , Harnain Christopher , Rozenblit Grigory
Published: August 2018

This chapter describes the use of a standard mushroom-retained gastrostomy (MRG) tube for stenting benign esophageal strictures. For effective long-term management, an esophageal stent should be easily placed, repositioned, and retrieved and also resistant to migration. An MRG tube can be used as a replaceable stent to allow oral feeding in the setting of benign esophageal stricture. The tube is readily available, easily adjustable, and an easily removable option. Using standard interventional techniques, the strictured segment is first dilated with a balloon catheter. The gastrostomy tube is then deployed over a guidewire. The tube spans the stricture, allowing for oral feeding.
Maximizing Visualization of the Needle During Ultrasound Procedures
Authors: Chin Ki Jinn
Published: August 2018

Safe and successful ultrasound-guided interventional procedures depend on the ability to visualize both anatomical structures of interest and the advancing needle. This chapter describes various strategies for optimizing needle visualization and tip localization during freehand guidance of a needle to a tissue target using ultrasound. Challenges to needle visualization include the poor echogenicity of standard needles at insertion angles steeper than 30–45 degrees to the horizontal, the difficulty of aligning the needle with the ultrasound beam, and manipulation in three dimensions based on two-dimensional visual information. Attention to ergonomics improves probe and needle control and facilitates alignment. Needle echogenicity can be improved by using a shallower angle, where possible, and echogenic needle technology. Hand movements of probe and needle should be kept small and controlled. Indirect cues of needle tip location are also extremely useful and should be utilized routinely.
Method for Optimal Tract Anesthesia During Biopsies, Drainage Catheter Placement, Nephrostomies, and Percutaneous Transhepatic Cholangiography
Authors: Heithaus Robert Evans , Syed Almas , Rees Chet R.
Published: August 2018

Transrectal and transvaginal approaches for abscess drainage can be safer than other approaches but may cause greater patient discomfort at the time of placement. Achieving optimal anesthesia can be difficult in certain situations, particularly when using a transvaginal or transrectal approach. By using a side port adapter and a high-quality 3-cc syringe, operators can provide additional anesthetic while using the Seldinger technique. This method allows for additional anesthetic to be placed in the vaginal cuff, thus allowing a greater number of transvaginal procedures to be performed with moderate sedation as opposed to general anesthesia. The technique can also be applied to other percutaneous procedures, such as nephrostomy tube placement.
Tract-o-gram to Reduce the Risk of Non-Target Catheterization During Placement of a Drainage Tube
Authors: Syed Almas , Heithaus Robert Evans , Rees Chet R.
Published: August 2018

A common complication of percutaneous drainage or tube placement is non-target catheterization, particularly of adjacent bowel loops. Bowel transgression by drainage catheters may later become evident by signs and symptoms of peritonitis, copious catheter output, sepsis, or fistula formation. However, small needle transgression alone, without tube transgression, is far less significant. This described method of pullback tract-o-gram can prevent placement of a tube once small needle transgression has occurred, and it can permit re-attempt and repeat safety check. The described method of tract-o-gram is simple, reproducible, eliminates extra exchanges or upsizing from a very small puncture size, and addresses the challenges of injecting contrast through small needles containing wires.
Creation of a Steerable Coaxial Needle System for Indirect Line-of-Site Computed Tomography-Guided Procedures
Authors: Kahn S. Lowell
Published: August 2018

A standard computed tomography (CT)-guided biopsy, aspiration, injection, or drainage procedure typically requires a direct line of access from the skin to the target lesion or collection. Safe performance of these procedures is ideally done without violation of vascular structures or solid or hollow viscous. When a direct pathway to the target is absent, patients are commonly denied the procedure and instead referred to surgery. This chapter describes a solution for CT-guided procedures when a direct line of access to the intended target is unavailable. The technique involves a coaxial needle system with simple modification (curving) of the inner needle.
Drainage of the Multiloculated Collection
Authors: Patel Mikin V. , Zangan Steven
Published: August 2018

Percutaneous drainage of an abscess is the standard of care and significantly improves patient outcomes. Typically, either trocar or Seldinger technique is used to access the abscess under ultrasound or computed tomography guidance. Pre-procedural planning is the most important step of the procedure, with the goal of using a safe, direct, short route to the collection. Vital anatomic structures such as sizeable arteries, solid organs (with a few exceptions), or a hollow viscus such as the stomach or colon should be avoided. Placement of a drain must balance effective positioning with a safe anatomic window for access. A multiloculated collection presents a special challenge because only one safe catheter approach may be available. In these cases, catheters with multiple side holes or multiple loops can be used to access the separate isolated components. Tissue plasminogen can also be utilized to break down the loculations and improve drainage.
Transurethral Retrograde Approach to Pelvic Abscess Drainage in Post-cystectomy Patients
Authors: Carberry George , Ozkan Orhan
Published: August 2018

One potential complication of radical cystectomy is the development of a pelvic abscess requiring drainage. Transurethral drainage has been described for the treatment of prostatic abscesses but is particularly well tolerated in patients for whom pelvic fluid drainage is needed following radical cystectomy. Although percutaneous, transrectal, or transvaginal approaches to pelvic drain placement are possible, the transurethral route provides a fully epithelialized tract through which the drainage catheter can traverse and which does not require unnecessary tissue puncture. Although blind Foley catheter placement could potentially be used for transurethral drainage in these patients, urologic surgeons have preferred fluoroscopically guided drain placement to ensure atraumatic placement and optimal drain positioning. In a stepwise fashion, this chapter describes how to perform fluoroscopy-guided transurethral abscess drainage in patients following cystectomy.
Use of a Peel-Away Sheath as a Method to Exchange a Clogged Drainage Tube
Authors: Jonna Harsha R. , Katz Michael D.
Published: August 2018

There are many methods of exchanging occluded or clogged percutaneous catheters. Typically, catheter exchange is simply performed over a guidewire. When debris occluding the lumen is compact, chronic, or extensive, such exchanges are difficult. Because salvaging an obstructed catheter, without risking loss of access, is difficult, multiple techniques to preserve organ access have been developed. This chapter describes a technique whereby a peel-away sheath is advanced over the catheter to re-establish organ access and facilitate catheter exchange. The placement of a coaxial peel-away sheath is useful for exchanging occluded enteric catheters, biliary drains, abscess drains, nephrostomies, and even selected vascular catheters.
Optimizing Carbon Dioxide Peripheral Arteriography
Authors: Patel Mikin V. , Zangan Steven
Published: August 2018

Angiography relies on the use of contrast medium for visualization of the vessel. Iodinated contrast can be contraindicated in patients with renal impairment or iodinated contrast allergy, so carbon dioxide (CO2) gas can be a useful alternative. A number of technical and postural parameters can optimize CO2 angiography, and vasodilators can be used to improve imaging of peripheral vessels. Although CO2 has distinct advantages, the limitations of CO2 angiography must be well understood. Operators should be aware that CO2 angiography can lead to overestimation of vessel size and can lead to complications such as transient ischemia of tissues, alterations of blood chemistry, neurotoxicity, and “vapor lock.”
Local Administration of Fresh Frozen Plasma and Platelets in the Critically Ill Patient
Authors: Abboud Salim E. , Nakamoto Dean A. , Haaga John R.
Published: August 2018

The locally injected blood elements (LIBE) technique represents a useful alternative to systemic administration of blood products to reduce the risk of periprocedural hemorrhage in coagulopathic patients. The LIBE technique results in the creation of a “seroma” of platelets and/or blood products along the expected needle or instrument path to allow a high-quality blood clot to form, and it requires relatively less blood products compared to the more traditional systemic administration technique. Indications for LIBE include and expand on those for systemic administration of blood products to reverse pre-procedural coagulopathy, including contraindications to systemic reversal of pharmacologic anticoagulation, precarious fluid volume status, severe coagulopathy unlikely to normalize with systemic administration of blood products, patient history of adverse reaction to systemic administration of blood products, and limited availability of the desired blood product.
Reducing Operator Exposure Using Suspended Radiation Protection System
Authors: Syed Almas , Heithaus Robert Evans , Rees Chet R.
Published: August 2018

The increasing utilization of radiation for diagnostic and therapeutic procedures has provided impetus for improved strategies of radiation protection for interventionalists. The associated discomfort, disability, and career-shortening effects of lead aprons for heavy fluoroscopy users have served as an impetus for the development of lighter and more comfortable models. A suspended radiation protection system employs the use of a “weightless” shield resembling a thick large lead apron with head shield and arm shields. The shield moves with the operator like a garment, providing extensive protection without orthopedic strain or discomfort while maintaining full user functionality. Utilization of a suspended radiation protection system provides the operator with optimum radiation protection, without any additional weight, and maintains procedural flexibility.
Emergency Department Visits After Elective Spine Surgery
Authors: Hills Jeffrey M , Khan Inamullah , Sivaganesan Ahilan , Weisenthal Benjamin , Daryoush Joshua , Butler Marjorie , Bydon Mohamad , Archer Kristin R , Asher Anthony , Devin Clinton J
Published: August 2018

BACKGROUND

Emergency department (ED) overuse is a costly and often neglected source of postdischarge resource utilization after spine surgery. Failing to investigate drivers of ED visits represents a missed opportunity to improve the value of care in spine patients.

OBJECTIVE

To identify the prevalence, drivers, and timing of ED visits following elective spine surgery.

METHODS

Patients undergoing elective spine surgery for degenerative disease at a major medical center were enrolled in a prospective longitudinal registry. Patient and surgery characteristics, and patient-reported outcomes were recorded at baseline and 3 mo after surgery, along with self-reported 90-d ED visits. A multivariable regression model was used to identify independent factors associated with 90-d ED visits. For a sample of patients presenting to our institution's ED, charts were reviewed to identify the reason and time to ED postdischarge.

RESULTS

Of 2762 patients, we found a 90-d ED visit rate of 9.4%. One-third of patients presented to our institution's ED and of these, 70% presented due to pain or medical concerns at 9 and 7 d postdischarge, respectively, with 60% presenting outside normal clinic hours. Independent risk factors for 90-d ED visits included younger age, preoperative opioid use, chronic obstructive pulmonary disorder, and more vertebral levels involved.

CONCLUSION

Nearly 10% of elective spine patients had 90-d ED visits not requiring readmission. Pain and medical concerns accounted for 70% of visits at our center, occurring within 10 d of discharge. This study provides the clinical details and a timeline necessary to guide individualized interventions to prevent unnecessary, costly ED visits after spine surgery.
Management of low-grade glioma: a systematic review and meta-analysis
Authors: Brown Timothy J , Bota Daniela A , van Den Bent Martin J , Brown Paul D , Maher Elizabeth , Aregawi Dawit , Liau Linda M , Buckner Jan C , Weller Michael , Berger Mitchel S , Glantz Michael
Published: August 2018

Background

Optimum management of low-grade gliomas remains controversial, and widespread practice variation exists. This evidence-based meta-analysis evaluates the association of extent of resection, radiation, and chemotherapy with mortality and progression-free survival at 2, 5, and 10 years in patients with low-grade glioma.

Methods

A quantitative systematic review was performed. Inclusion criteria included controlled trials of newly diagnosed low-grade (World Health Organization Grades I and II) gliomas in adults. Eligible studies were identified, assigned a level of evidence for every endpoint considered, and analyzed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The relative risk of mortality and of progression at 2, 5, and 10 years was calculated for patients undergoing resection (gross total, subtotal, or biopsy), radiation, or chemotherapy.

Results

Gross total resection was significantly associated with decreased mortality and likelihood of progression at all time points compared to subtotal resection. Early radiation was not associated with decreased mortality; however, progression-free survival was better at 5 years compared to patients receiving delayed or no radiation. Chemotherapy was associated with decreased mortality at 5 and 10 years in the high-quality literature. Progression-free survival was better at 5 and 10 years compared to patients who did not receive chemotherapy. In patients with isocitrate dehydrogenase 1 gene (IDH1) R132H mutations receiving chemotherapy, progression-free survival was better at 2 and 5 years than in patients with IDH1 wild-type gliomas.

Conclusions

Results from this review, the first to quantify differences in outcome associated with surgery, radiation, and chemotherapy in patients with low-grade gliomas, can be used to inform evidence-based management and future clinical trials.