Percutaneous Transhepatic Drainage of Inaccessible Abdominal Abscesses Following Abdominal Surgery Under Real-Time CT-Fluoroscopic Guidance

Computed Tomography-guided Puncture: Preprocedural Preparation, Technical Tips, and Radioprotection

Computed tomography-guided puncture is a useful technique for various interventional radiology procedures. Puncture from various locations and angles becomes possible using this technique. Moreover, bone and air do not interfere with the computed tomography image. Therefore, computed tomography-guided puncture is feasible even in difficult cases of ultrasonography-guided procedures. However, a computed tomography-guided procedure can cause radiation exposure to patient and operator. Therefore, utmost attention should be given to minimizing radiation exposure. This study aimed to provide a brief review of pre-procedural preparation and the technical tips for the computed tomography-guided puncture and introduce recent topics related to the radioprotection of computed tomography-guided puncture.

Dispelling the Myths of Percutaneous Catheter Drainage of Infected Abdominal Collections

When consulted for percutaneous catheter drainage (PCD) of abdominopelvic collections, interventional radiologists (IRs) should consider the appropriateness of this technique in the context of other options such as conservative, endoscopic, or surgical management. Whenever possible, published data should be considered prior to performing percutaneous drainage, especially as regards controversial scenarios such as the use of fibrinolytic therapy, the primary placement of large-bore drainage catheters, the drainage of cystic tumors, the drainage of splenic abscesses, and the treatment of collections lacking an in-line drainage window. This article examines past and present published data on PCD to dispel some common myths and guide IRs toward the best applications of PCD.

Radioprotective Effects of a Semicircular X-ray Shielding Device for Operators During CT Fluoroscopy-Guided Interventional Procedures: Experimental and Clinical Studies

PURPOSE

To evaluate, experimentally and clinically, the radioprotective effects of a semicircular X-ray shielding device for operators during CT fluoroscopy-guided IR procedures.

MATERIALS AND METHODS

During experimentation, the reduction rates of scattered radiation rates from CT fluoroscopy were evaluated using a humanoid phantom. Two shielding device positions were tested: "shielding close to the CT gantry" and "shielding close to the operator". The scattered radiation rate without shielding was also evaluated. The clinical study retrospectively evaluated the operator's radiation exposure during 314 CT-guided IR procedures. With a semicircular X-ray shielding device (with shielding group, n = 119) or without it (no shielding group, n = 195), CT fluoroscopy-guided IR procedures were performed. Radiation dose measurements were taken using a pocket dosimeter placed near the operator's eye. For shielding and no shielding groups, the procedure time, dose length product (DLP), and the operator's radiation exposures were compared.

RESULTS

Experimentation revealed the respective mean reduction rates of "shielding close to the CT gantry" and "shielding close to the operator" as 84.3% and 93.5% compared with the no-shielding setting. Although no significant differences were found in the procedure time and the DLP between "no shielding" and "with shielding" groups in the clinical study, the operators' radiation exposure in the "with shielding" group (0.03 ± 0.04 mSv) was significantly lower than in the "no shielding" group (0.14 ± 0.15 mSv; p < .001).

CONCLUSION

The semicircular X-ray shielding device provides valuable radioprotective effects for operators during CT fluoroscopy-guided IR.

Indian College of Radiology and Imaging Consensus Guidelines on Interventions in Pancreatitis

Acute pancreatitis (AP) is one of the common gastrointestinal conditions presenting as medical emergency. Clinically, the severity of AP ranges from mild to severe. Mild AP has a favorable outcome. Patients with moderately severe and severe AP, on the other hand, require hospitalization and considerable utilization of health care resources. These patients require a multidisciplinary management. Pancreatic fluid collections (PFCs) and arterial bleeding are the most important local complications of pancreatitis. PFCs may require drainage when infected or symptomatic. PFCs are drained endoscopically or percutaneously, based on the timing and the location of collection. Both the techniques are complementary, and many patients may undergo dual modality treatment. Percutaneous catheter drainage (PCD) remains the most extensively utilized method for drainage in patients with AP and necrotic PFCs. Besides being effective as a standalone treatment in a significant proportion of these patients, PCD also provides an access for percutaneous endoscopic necrosectomy and minimally invasive necrosectomy. Endovascular embolization is the mainstay of management of arterial complications in patients with AP and chronic pancreatitis. The purpose of the present guideline is to provide evidence-based recommendations for the percutaneous management of complications of pancreatitis.

CT-Guided Transhepatic Catheter Drainage of Deep Postoperative Collections: Initial Experience

Introduction This article assesses the safety and utility of transhepatic drainage of deep seated postoperative intra-abdominal collections under computed tomography (CT) guidance in a short series.

Materials and Methods This retrospective study included five patients (mean age: 45.8 years; 3 males, 2 females) who underwent CT-guided transhepatic drainage of postoperative abdominal abscess in our department between April 2019 and December 2020. The clinical and surgical details and the details of the transhepatic drainage procedure were evaluated along with success rates and complications.

Results The surgical procedures were Whipple's pancreaticoduodenectomy in four patients and gastrectomy in one patient. Four out of five abscesses were drained through the right lobe of liver, while one was through the left lobe with a technical success rate of 100%. The mean total time for catheter drainage procedure including patient positioning and preparation was 29.2 minutes. None of the patients had procedure-related complications. Mean duration of catheter drainage was 12 days. All patients had complete resolution of symptoms after drainage and the clinical success rate was 100%.

Conclusion Transhepatic approach is safe and effective for the drainage of inaccessible postoperative abdominal collections or abscesses where a standard percutaneous approach is not possible.

Percutaneous Transhepatic Biopsy for Extrahepatic Lesions

Purpose The purpose was to assess the diagnostic accuracy and safety of percutaneous transhepatic biopsy for extrahepatic lesions.

Materials and Methods Between January 2008 and December 2019, 26 patients (17 men and 9 women; median age, 60 years) underwent percutaneous transhepatic needle biopsy for extrahepatic lesions at our institution. Transhepatic biopsy was deemed appropriate compared with other biopsy routes or methods (i.e., endoscopic or surgical). The lesions were in the porta hepatis (n = 9), retroperitoneum (n = 6), right adrenal gland (n = 4), right kidney (n = 3), lesser omentum (n = 2), duodenum (n = 1), pleura (n = 1), and inferior vena cava (n = 1). The median maximal diameter of the lesions was 45.5 mm (range, 18–148 mm). Core-needle biopsy was performed in all patients. Eighteen-gauge and 21-G needles were used in 25 and one patient, respectively. Ultrasound was used for biopsy in 21 patients, and CT fluoroscopy was used in five patients. Postbiopsy tract embolization was performed in three patients. Technical success and diagnostic accuracy of the biopsy were evaluated. Complications were recorded using the systemic inflammation response (SIR) criteria.

Results The pathological results of biopsy were carcinoma (n = 10), lymphoma (n = 9), and other diagnoses (n = 7). Technical success was obtained in all patients. The accurate diagnosis was achieved in 24 of the 26 patients (92.3%). A major complication, a bladder tamponade, was observed in one patient (3.8%) after biopsy of a right kidney lesion. A hematoma caused by iatrogenic renal injury likely obstructed the bladder outlet. Minor complications were observed in three patients (11.5%).

Conclusions Percutaneous transhepatic biopsy for extrahepatic lesions is feasible with acceptable safety.

ACR Appropriateness Criteria® Radiologic Management of Infected Fluid Collections

Infected fluid collections are common and occur in a variety of clinical scenarios throughout the body. Minimally invasive image-guided management strategies for infected fluid collections are often preferred over more invasive options, given their low rate of complications and high rates of success. However, specific clinical scenarios, anatomic considerations, and prior or ongoing treatments must be considered when determining the optimal management strategy. As such, several common scenarios relating to infected fluid collections were developed using evidence-based guidelines for management. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

CT-guided special approaches of drainage for intraabdominal and pelvic abscesses: One single center's experience and review of literature

BACKGROUND

To explore the safety and efficacy of several special approaches of drainage for deep inaccessible intraabdominal and pelvic abscesses.

METHODS

By searching of our institutional database, the clinical and radiologic information of all patients with special approaches of abscesses drainage was collected, consisting of etiology, diameter of abscess, duration of drainage, major complications, rates of success, failure and death, and pre-procedure, intra-procedure and post-procedure computed tomography scans.

RESULTS

A total of 124 patients are eligible for the criterion in our center between January 2010 and January 2018. The mean diameter of abscess was 5.6 cm (range 3.0-9.8 cm) and mean duration of drainage was 10.3 days (range 4-43 days). Pain was complained in 6 patients (4.8%) and hemorrhage was observed in one patient. Complete resolution of the abscess following drainage was observed in 115 patients (92.7%). A total of 9 patients (7.3%) failed to percutaneous abscess drainage and 3 patients died of catheter-unrelated diseases. Transintestinal afferent loop of drainage was firstly attempted in six patients and complete resolution of abscess was achieved in five patients.

CONCLUSION

Special approaches, including transgluteal, presacral space, transhepatic, multiplane reconstruction (MPR)-assisted oblique approach and transintestinal afferent loop approach for those deep inaccessible intraabdominal and pelvic abscesses are safe and feasible.

A New CT-Guided Modified Trocar Technique for Drainage of Difficult Locations Abscesses

PURPOSE

Computed tomography (CT) is commonly used to guide drainage of deep-seated abdominal fluid collections. However, in some cases, these collections seem to be inaccessible due to surrounding organs or their being in difficult locations. The aim of this study is to describe a modified Trocar technique to drain collections in difficult locations, especially those in the subphrenic space, without passing through intervening organs.

MATERIALS AND METHODS

This retrospective case series study describes seven inpatients who underwent CT-guided drainage using a modified Trocar technique for abscesses that are difficult to access percutaneously. All patients provided written informed consent prior to the procedure. After placement of a 12-14F catheter inside the peritoneum, the Trocar stylet was removed so that the tip of the catheter became blunt and flexible to avoid injury to organs and structures in the catheter route, and the catheter was slowly advanced towards the collection using CT guidance and tactile sensation. After reaching the target, the stylet was reintroduced to enter the abscess wall.

RESULTS

All procedures were performed using an anterior abdominal wall access with adequate catheter positioning and resulted in clinical status improvement in the days after the drainage. No complications related to the procedure were identified in any of the patients.

CONCLUSIONS

The modified Trocar technique for percutaneous CT-guided drainage of abdominal abscesses may be feasible for lesions that are difficult to access with conventional methods.

Cone-Beam CT with Fluoroscopic Overlay Versus Conventional CT Guidance for Percutaneous Abdominopelvic Abscess Drain Placement

PURPOSE

To compare technical success and procedure time for percutaneous abscess drain placement with fluoroscopic cone-beam computed tomography (CT) and two-axis needle guidance versus conventional CT guidance.

MATERIALS AND METHODS

A total of 85 consecutive patients undergoing abdominopelvic abscess drain placement guided by fluoroscopic cone-beam CT or conventional CT were retrospectively reviewed over a 2-year period. Forty-three patients underwent drain placement with cone-beam CT using XperGuide navigation and 42 underwent placement with conventional 64-slice CT. Patient characteristics, median abscess size (6.8 cm vs 7.8 cm; P = .14), and depth to abscess (7.2 cm vs 7.7 cm; P = .88) were similar between groups.

RESULTS

Technical success rates were 98% (42 of 43) in the cone-beam CT group and 100% (42 of 42) in the conventional CT group (P = .32), with a 10-F pigtail drainage catheter inserted in the majority of cases. There were no complications in either group. There was no significant difference in effective dose between groups (9.6 mSv vs 10.7 mSv; P = .30). Procedure times were significantly shorter in the cone-beam CT group (43 min vs 62 min; P = .02). In addition, during the study period, there was a gradual improvement in procedure time in the cone-beam CT group (50% reduction), whereas procedure time did not change for the conventional CT group.

CONCLUSIONS

Cone-beam CT guidance appears to be equivalent to conventional CT guidance for drain placement into medium-sized abdominopelvic collections, yielding similar technical success rates and radiation doses, with the additional benefit of reduced procedure times.

Approaches to the difficult drainage and biopsy

Percutaneous abscess drainage and percutaneous biopsy are effective and widely used techniques in the diagnosis and treatment of patients with abdominal or pelvic abscesses and lesions. Some abscesses and lesions can initially appear unsuitable for percutaneous access for a variety of reasons. This article reviews the circumstances in which collections or lesions may appear undrainable or inaccessible to percutaneous biopsy, and it describes techniques for overcoming these circumstances.

Radiologic drainage of post-operative collections and abscesses

Since the initial studies published in the eighties, percutaneous radiologic drainage, is considered the first-line treatment of infected post-operative collections and is successful in over 80% of patients. Mortality due to undrained abscesses is estimated between 45 and 100%. Radiology-guided percutaneous drainage can be performed either with curative intent or to improve patient status prior to re-operation under better conditions. Cross-sectional imaging, using either ultrasound or computed tomography (CT), has changed the management of post-operative complications. Percutaneous drainage is most often performed by interventional radiologists and imaging is essential for road-mapping and guiding the puncture and drainage of intra-abdominal collections. Indeed, such imaging allows both identification of adjacent anatomical structures and determination of the best tract and the safest route. Cooperation between the surgeon and the interventional radiologist is essential to optimize the management and to avoid, if possible, surgery, which is so often difficult in this setting.