Faculty Bibliography

Familiarity with different instruments and understanding the basics of image guidance techniques are essential for interventional radiology trainees. However, there are no structured references in the literature, and trainees are left to "pick it up as they go". Puncture needles, guidewires, sheath systems, and catheters represent some of the most commonly used daily instruments by interventional radiologists. There is a large variety of instruments, and understanding the properties of each tool will allow trainees to better assess which type is needed for each specific procedure. Along with understanding the tools required to perform various interventional radiology procedures, it is important for trainees to learn how to organize the room, procedural table, and various equipment that is used during the procedure. Minimizing clutter and improving organization leads to improved efficiency and decreased errors. In addition, having a fundamental knowledge of fluoroscopy, the most commonly used imaging modality, is an integral part of beginning training in interventional radiology.

Background: Hospitalized patients often undergo interventional radiology (IR) procedures, many of which require individualized pre-procedure preparation and post-procedure care. Internists caring for these patients may not be familiar with requirements for these patients, causing procedural delays or periprocedural adverse events. Clear communication between IR and internal medicine is therefore necessary, but is often lacking.
Method(s): We conducted qualitative interviews with hospitalists, house staff, nurses and IR staff to identify common breakdowns in periprocedural communication between IR and referring medicine units. Utilizing insights from these interviews, we identified essential elements for pre-procedure and post-procedure communication. These elements were added as fields in templated pre-and post-procedure IR notes (Table 1). Each standardized template contains 16 elements. Outcome measures included proportion of key elements included in IR notes, inpatient provider satisfaction, and frequency of phone calls into and out of IR before and after the intervention.
Result(s): Before implementation of the standardized templates, pre-procedure consult notes (N=25) contained an average of 3.5 key elements (typically a brief medical history, assessment and plan), while post-implementation (N=50), these notes contained an average of 15.3 elements (p< 0.001). Similarly, post-procedure notes (N=25) contained an average of 4.7 elements (typically the names of the IR providers, a brief procedure description and patient condition) pre-intervention versus a mean of 15.0 elements post-intervention (N=50) (p< 0.001). Surveys of hospitalists pre-(N=17) and post-intervention (N=10) showed no significant difference in lack of confidence in preparing patients for IR procedures (52.9% vs. 30.0%, p=0.40), ineffective collaboration with IR (11.8% vs. 0%, p=0.44), and not receiving clear recommendations (35.3% vs. 10%, p=0.67); however analyses were underpowered. Total calls into and out of VIR decreased 15.6% overall (mean decrease of 7.7 calls/weekday and 24.5 calls/weekend, p=.006).
Conclusion(s): Standardizing pre-and post-procedure documentation can effectively increase the inclusion of key content, and this content may reduce internal medicine physician questions and concerns regarding periprocedural patient care

Purpose: To evaluate safety and effectiveness of yttrium-90 radioembolization to treat hepatic metastases in uveal melanoma patients that also received adjuvant immunotherapy. Materials: Retrospective review of 11 patients with metastatic uveal melanoma who received 18 radioembolization treatments between June 2015 and February 2018 (3 treatments with resin and 15 with glass yttrium-90 microspheres). All patients also received adjuvant immunotherapy. Progression of hepatic disease was determined using the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Overall survival and hepatic progression free survival were calculated from date of second treatment when applicable. Result(s): Median hepatic progression free survival was 8.6 months (1.6-24.3 months) and median overall survival was 13.6 months (1.6-28.2 months) following radioembolization. Overall local tumor control (complete response, partial response or stable disease) was achieved in 63.6% (7/11) of patients. One patient transitioned to hospice 1.6 months post-procedure due to worsening liver disease and functional status. Four patients demonstrated progression of hepatic disease and two of these patients received repeat radioembolization with glass microspheres after initial treatment with resin microspheres. The first patient experienced an additional 3.3 months of hepatic progression free survival following repeat treatment and 19.6 months of overall survival prior to death from extrahepatic disease. The second patient experienced complete response to repeat treatment with 2.8 months of ongoing hepatic progression free survival and 11.4 months of ongoing overall survival. The remaining six patients demonstrated ongoing hepatic progression free survival of 11.6 months (5.5-24.3 months) and overall median survival of 14.4 months (7.7-24.4 months). Conclusion(s): Radioembolization in combination with systemic immunotherapy appears to be a safe and effective treatment of uveal melanoma hepatic metastases. This cohort demonstrated local tumor control in 63.6% of patients with median overall survival of 13.6 months and median hepatic progression free survival of 8.6 months following locoregional treatment.

Purpose: To determine whether routine preoperative evaluation of patient coagulation status, as reflected by the calculated International Normalized Ratio (INR), is necessary prior to placement of a tunneled subcutaneous port. Materials: We conducted a retrospective analysis of tunneled subcutaneous port placements performed by interventional radiology in the ambulatory setting at a single institution over a 6-month period from March to September 2017. The INR values at time of initial outpatient referral, as well as any subsequent preoperative coagulation testing, were compiled from the electronic medical record. Any INR abnormalities, defined as a value greater than 1.5, were then cross-referenced with specific patient past medical history. Results: A total of 263 patients had subcutaneous ports placed during the 6-month study period (29.7% male, mean age 59). INR testing was performed within 30 days of port placement for every patient, as per departmental protocol based on the Society of Interventional Radiology (SIR) guidelines for management of patient coagulation status. Of the 263 port placements, only 4 patients (1.5%) demonstrated INR values above the threshold limit: Two patients were on Coumadin therapy for chronic thromboembolic disease and atrial fibrillation respectively, one patient was on Apixaban (Eliquis) for atrial fibrillation and one patient had known non-Alcoholic steatohepatitis (NASH) cirrhosis. Conclusions: The incidence of an abnormal INR in patients is very low. Within the study period, only 1.5% of patients undergoing tunneled subcutaneous port placement demonstrated a coagulation abnormality on routine preoperative testing. All noted abnormalities were explained by a review of the individual patient medical history; specifically, these patients were either on anticoagulation or had known hepatic dysfunction. These findings suggest that the majority of patients do not require routine preoperative testing of coagulation status and that a preprocedural INR can be obtained on a case-by-case basis as predicted by relevant patient medical history

Computed tomography pulmonary angiography (CTPA) has become the primary imaging modality for evaluating the pulmonary arteries. Although pulmonary embolism is the primary indication for CTPA, various pulmonary vascular abnormalities can be detected in adults. Knowledge of these disease entities and understanding technical pitfalls that can occur when performing CTPA are essential to enable accurate diagnosis and allow timely management. This review will cover a spectrum of acquired abnormalities including pulmonary embolism due to thrombus and foreign bodies, primary and metastatic tumor involving the pulmonary arteries, pulmonary hypertension, as well as pulmonary artery aneurysms and stenoses. Additionally, methods to overcome technical pitfalls and interventional treatment options will be addressed.

OBJECTIVE: Recalling a patient to repeat a radiology examination is an adverse and, in certain cases, preventable event. Our objectives were to assess the rate of patient recalls for all imaging performed in the outpatient setting at our institution and to characterize the underlying reasons for the recalls. MATERIALS AND METHODS: We performed a retrospective review of all repeat imaging requests for an inadequate initial imaging study between January 2012 and March 2015. RESULTS: We identified 100 recall requests (mean, 2.6 requests per month), for an overall recall rate of approximately 1 in 8046 ambulatory studies and 1 in 1684 MRI studies. Nearly all recalls (98%) involved adults. A total of 95% of the recalls were for MRI studies. The most common reason for a patient recall request was an incomplete examination, making up 24% of all requests. The other causes were inadequate coverage of the area of interest (22%), protocoling errors (20%), poor imaging quality (15%), additional imaging to clarify a finding (11%), insufficient contrast visualization (7%), and incorrect patient information (1%). CONCLUSION: We found that patient recalls for imaging in the outpatient setting at our institution are not common. When recalls did occur, they were most often related to the acquisition of MR images. Improved technologist education on MRI protocoling and enhanced communication between ordering clinicians and radiologists to clarify the purpose of imaging might reduce the need for repeat ambulatory imaging.

Purpose: To compare placement of inferior vena cava filters (IVCF) in the fluoroscopy suite (FS) and in the operating room (OR) with regard to radiation exposure, filter position, and cost. Materials: All IVCF placements (8/13-12/14) at a single tertiary hospital center were identified through a picture archiving and communication system (PACS) engine search. The administered medications, procedure time, anesthesia services, radiation exposure, and filter type and angulation were recorded. Cost was estimated using information available in the hospital cost allocation system including time of procedure, procedure/recovery location, typically administered medications, and type of filter typically used in each area; the cost of anesthesiology consultation was excluded as it was unavailable in the allocation system. Results: In total, 254 IVCFs were placed in the FS and 47 filters in the OR. IVCF placements performed in the OR entailed radiation doses (156.3 mGy vs. 72.2 mGy, p=0.001) and fluoroscopy times (6.1 min vs. 2.8 min, p<0.0001) that were twice as high as those performed in the FS. Angulation of deployed filters from the central axis of the IVC was significantly less for those placed in the FS than for in the OR (2.6degree vs 4.8degree p<0.0001). There was a significant difference in the type of anesthesia used, with general anesthesia or monitored anesthesia care preferred in the OR (84%), whereas an anesthesiologist was involved in only 5% of FS cases. Most (92%) FS cases involved only a local anesthetic (p< 0.0001) and physiologic monitoring. Cost savings of FS cases compared with OR cases were estimated to be more than $488.77 per case. Conclusions: IVCF placement in the FS, compared to the OR, resulted in less exposure to radiation, more precise filter placement, and reduced cost

Purpose: To evaluate difficulty of inferior vena cava (IVC) filter retrieval among three different filter types as determined by fluoroscopy time and additional equipment use beyond a routine snare and sheath. Materials: A retrospective, two-center review was performed of 74 patients who underwent IVC filter retrieval during a 34 month period (41 women and 33 men, mean age 57). 32 Denali (Bard Vascular, Tempe, AZ), 12 ALN (ALN Implants, Ghisonaccia, France), and 30 Option (Argon Medical Devices, Plano, Texas) filters were successfully removed. Demographics, venography and procedural reports were evaluated and statistical analysis was used to determine significant variables affecting filter retrieval. Results: There was no significant difference between filters based on demographics, dwell time, or operator. Filter tilt (defined as >5degree) at retrieval was significantly associated with increased retrieval time (Mann-Whitney U=894.5, p=0.012) and was present in 56.8% (42/74) of cases with significantly different rates between filter types: 37.5% (12/32) of Denali, 58.3% (7/12) of ALN, and 76.7% (23/30) of Option (%2=8.26, p=0.016). However, there was no significant difference in the degree of tilt: 7.9degree for Denali, 10.7 for ALN, and 7.8 for Option (Kruskal-Wallis H=2.00, p=0.368). Among filters with tilt, mean fluoroscopy retrieval times were 3.8 min (SD 2.7) for Denali, 8.3 min (SD 5.4) for ALN, and 20.2 min (SD 17.5) for Option. Retrieval times were significantly different (H=15.23, p < 0.0001) with post-hoc analysis demonstrating a significance between Denali and Option (16.4 min, p< 0.0001) only. Non-tilted filters had no significant difference in retrieval time (H=5.29, p=0.071). Filter tilt >5 also required significant additional equipment at retrieval (chi²=10.65, p=0.001) but only for ALN and Option. Zero Denali, 28.6% (2/7) of ALN and 56.5% (13/23) of Option tilted retrievals required additional equipment (chi²=11.83, p=0.003). Conclusions: Filter tilt leads to increased fluoroscopy time and additional equipment use at retrieval. However, compared to ALN and Option, Denali filters demonstrate less frequent tilt and require no additional equipment for retrieval even when tilt is present

Purpose: Delineate sources of increased radiation during, cost of, and difficult retrieval after IVC filter (IVCF) placement. Material and methods: All 299 IVCFs (8/2013-12/2014) were identified by PACS search, 252 placed in a fluoroscopy suite (FS) and 47 in the operating room (OR), and reviewed for radiation exposure, fluoroscopy time, filter type, and angulation. Filter removals were assessed for the number of retrieval devices needed and fluoroscopy time. Results: Multiple linear regressions revealed that jugular versus femoral access and filter type had no impact on radiation exposure. However, filters placed in the OR entailed more radiation than in the FS (156.3 vs 71.4 mGy; p=0.001), longer fluoroscopy time (6.1 vs 2.8 min; p<0.0001), and resulted in greater filter angulation (4.8 vs 2.6degree; p<0.0001). Filter angulation was primarily dependent on the filter type (p=0.02), with the Venatech and Denali filters associated with decreased angulation (2.2 and 2.4degree, respectively), and the Option, Celect, and Meridian filters associated with greater angulation (4.2, 4.6, 4.7degree, respectively). There was a 32% retrieval rate. Filter angulation, but not filter type or filtration duration, independently predicted cases requiring more >1 retrieval device (p=0.0008) and >30 min fluoroscopy time (p=0.02). Cost savings for IVCF placement in the FS versus OR were estimated at $444.50/case. Conclusion: Increased radiation and cost were associated with placement in the OR, compared to the FS. Filter angulation was the primary determinant of difficulty in removing filters, while angulation was determined by filter type. Performing IVCF placement in the FS using specific filters may reduce radiation and cost, while enabling subsequent ease of retrieval