Proposal of a New Adverse Event Classification by the Society of Interventional Radiology Standards of Practice Committee.

PURPOSE: To develop a new adverse event (AE) classification for the interventional radiology (IR) procedures and evaluate its clinical, research, and educational value compared with the existing Society of Interventional Radiology (SIR) classification via an SIR member survey. MATERIALS AND METHODS: A new AE classification was developed by members of the Standards of Practice Committee of the SIR. Subsequently, a survey was created by a group of 18 members from the SIR Standards of Practice Committee and Service Lines. Twelve clinical AE case scenarios were generated that encompassed a broad spectrum of IR procedures and potential AEs. Survey questions were designed to evaluate the following domains: educational and research values, accountability for intraprocedural challenges, consistency of AE reporting, unambiguity, and potential for incorporation into existing quality-assurance framework. For each AE scenario, the survey participants were instructed to answer questions about the proposed and existing SIR classifications. SIR members were invited via online survey links, and 68 members participated among 140 surveyed. Answers on new and existing classifications were evaluated and compared statistically. Overall comparison between the two surveys was performed by generalized linear modeling. RESULTS: The proposed AE classification received superior evaluations in terms of consistency of reporting (P < .05) and potential for incorporation into existing quality-assurance framework (P < .05). Respondents gave a higher overall rating to the educational and research value of the new compared with the existing classification (P < .05). CONCLUSIONS: This study proposed an AE classification system that outperformed the existing SIR classification in the studied domains.

Survey of current status and physician opinion regarding ancillary staffing for the IR suite.

PURPOSE: To survey the status quo of ancillary staffing in predominantly hospital-based interventional radiology (IR) suites and to assess interventional radiologist attitudes toward current IR procedure room staffing availability and appropriateness. MATERIALS AND METHODS: Invitations to an online survey composed of 26 questions focused on levels of IR suite ancillary staffing as well as operators' opinions of current IR procedure room staffing were sent via email to 2,284 active Society of Interventional Radiology members. RESULTS: There were 777 survey responses. Nurse staffing count per IR room was at least one in 90% (n = 699) during regular hours and 93.6% (n = 730) during off-hours, respectively. A second technologist was frequently used during regular hours and, to a lesser extent, during on-call hours (n = 341 [43.9%] and n = 122 [15.7%]), respectively. Ten and 15% of IR respondents believe staffing support is inadequate for most interventional procedures requiring moderate sedation during normal business hours and off-hours/weekends, respectively, and 69% and 56% of IR respondents believe anesthesia support is inadequate during normal business hours and during off-hours, respectively. CONCLUSIONS: The number of technologists used per IR suite varies across practices and frequently exceeds that of earlier American College of Radiology recommendations, whereas use of IR suite nurse staffing is consistent with approximately one per suite and constant. However, there is dissatisfaction among surveyed interventional radiologists with availability and appropriateness of staffing of the IR procedure room, particularly during on-call hours and weekends, as well as with anesthesia support for emergent cases. No evidence-based guidelines for staffing the IR suite currently exist. This underscores the need for further investigation with the ultimate goal of creating such guidelines.

Contrast enhanced MR venography with gadofosveset trisodium: evaluation of the intracranial and extracranial venous system.

PURPOSE: To demonstrate the efficacy of contrast enhanced magnetic resonance venography (CEMRV) using gadofosveset trisodium in the comprehensive evaluation of the intracranial and extracranial venous system. MATERIALS AND METHODS: Temporal signal decay, in-plane saturation and flow artifacts were assessed in an institutional review board approved, HIPAA compliant CEMRV study of 99 subjects. In a 39 subject subset, percent diameter narrowing of the internal jugular (IJ), brachiocephalic and azygous veins were coded according to the following ordinal grades for both catheter venography (CV) and CEMRV: grade 0 ≤ 50%, grade 1 >50% and ≤ 75%, grade 2 >75% and <100% and grade 3 = 100% and compared with pressure gradient measurements obtained during CV. RESULTS: There was no significant signal decay, in-plane saturation or flow artifacts identified on CEMRV or hemodynamically significant pressure gradients identified on CV. All brachiocephalic and azygous veins had matched grade 0 narrowing on both modalities. Discrepancy between modalities occurred in the IJ veins at the level of thyroid gland where 15% of IJ veins had CEMRV grade ≥ 1 narrowing compared with 4% for CV or below the thyroid gland where 5% of IJ veins had CEMRV grade ≥ 1 narrowing compared with 20% for CV. There was fair agreement (κ = 0.24) between modalities for grade of narrowing in the combined data set of all coded veins. CONCLUSION: CEMRV using gadofosveset trisodium is accurate in the evaluation of the venous system.

Are we delivering two standards of care for pelvic trauma? Availability of angioembolization after hours and on weekends increases time to therapeutic intervention.

BACKGROUND: We hypothesized that patients with pelvic fractures and hemorrhage admitted during daytime hours were undergoing interventional radiology (IR) earlier than those admitted at night and on weekends, thereby establishing two standards of time to hemorrhage control. METHODS: The trauma registry (January 2008 to December 2011) was reviewed for patients admitted with pelvic fractures, hemorrhagic shock, and transfusion of at least 1 U of blood. The control group (DAY) was admitted from 7:30 AM to 5:30 PM Monday to Friday, while the study group (after hours [AHR]) was admitted from 5:30 PM to 7:30 AM, on weekends or holidays. RESULTS: A total of 191 patients met the criteria (45 DAY, 146 AHR); 103 died less than 24 hours and without undergoing IR (29% DAY group vs. 62% AHR, p < 0.001). Sixteen patients (all in AHR group) died while awaiting IR (p = 0.032). Eighty-eight patients (32 DAY, 56 AHR) survived to receive IR. Among these, the AHR group were younger (median, 30 years vs. 54 years; p = 0.007), more tachycardic (median pulse, 119 beats/min vs. 90 beats/min; p = 0.001), and had more profound shock (median base, -10 vs. -6; p = 0.006) on arrival. Time from admission to IR (median, 301 minutes vs. 193 minutes; p < 0.001) and computed tomographic scan to IR (176 minutes vs. 87 minutes, p = 0.011) were longer in the AHR group. There was no difference in the 30-day mortality by univariate analysis. However, after controlling for age, arrival physiology, injury severity, and degree of shock, the AHR group had a 94% increased risk of mortality. CONCLUSION: The current study demonstrated that patients admitted at night and on weekends have a significant increase in time to angioembolization compared with those arriving during the daytime and during the week. Multivariate regression noted that AHR management was associated with an almost 100% increase in mortality. While this is a single-center study and retrospective in nature, it suggests that we are currently delivering two standards of care for pelvic trauma, depending on the day and time of admission. LEVEL OF EVIDENCE: Therapeutic study, level II.

Chronic cerebrospinal venous insufficiency: masked multimodal imaging assessment.

BACKGROUND: Chronic cerebrospinal venous insufficiency (CCSVI) was implicated in the pathophysiology of multiple sclerosis (MS). OBJECTIVE: We evaluated neurosonography (NS), magnetic resonance venography (MRV), and transluminal venography (TLV) in subsets of MS patients drawn from a single-center, prospective, case-control study of 206 MS and 70 non-MS volunteers. METHODS: As previously reported, findings on high-resolution B-mode NS imaging with color and spectral Doppler of the extracranial and intracranial venous drainage consistent with CCSVI were similar among MS and non-MS volunteers (3.88% vs 7.14%; p = 0.266). Ninety-nine MS participants consented to intravascular contrast-enhanced 3D MRV to assess their major systemic and intracranial venous circulation, and 40 advanced to TLV that included pressure measurements of the superior vena cava, internal jugular, brachiocephalic, and azygous veins. RESULTS: NS findings and MRV patterns were discrepant for 26/98 evaluable subjects, including four with abnormal findings on NS that had normal venous anatomy by MRV. In no instance were TLV pressure gradients indicative of clinically significant functional stenosis encountered. The three imaging approaches provided generally consistent data with discrepancies referable to inherent technique properties. CONCLUSIONS: Our findings lend no support for altered venous outflow dynamics as common among MS patients, nor do they likely contribute to the disease process.

Chronic cerebrospinal venous insufficiency: case-control neurosonography results.

OBJECTIVE: Chronic cerebrospinal venous insufficiency (CCSVI) has been implicated in the pathophysiology of multiple sclerosis (MS). We sought to determine whether neurosonography (NS) provides reliable information on cerebral venous outflow patterns specific to MS. METHODS: This was a single-center, prospective case-control study of volunteer MS and non-MS participants. A neurosonologist, blind to the subjects' diagnosis, used high-resolution B-mode imaging with color and spectral Doppler to systematically investigate, capture, and record extracranial and intracranial venous drainage. These neuroimaging results were evaluated and scored by an expert blinded to subjects' information and with no interactions with the participants. RESULTS: Altogether, 276 subjects were studied: 206 with MS and 70 non-MS. MS patients were older than non-MS subjects (48.3±9.9 vs 44.3±11.8 years, p<0.007), with durations from first symptoms and diagnosis of 13.7±10 and 9.9±7.8 years, and Expanded Disability Status Scale of 2.6±2.0. Overall, 82 subjects (29.7%) fulfilled 1 of 5 NS criteria proposed for CCSVI; 13 (4.7%) fulfilled 2 criteria required for diagnosis, and none fulfilled >2 criteria. The distribution of subjects with 0, 1, or 2 criteria did not differ significantly across all diagnostic groupings, between MS and non-MS subjects, or within MS subgroups. CCSVI was present in 7.14% of non-MS and 3.88% of MS patients (p=0.266). No significant differences emerged between MS and non-MS subjects for extracranial or intracranial venous flow rates. INTERPRETATION: NS findings described as CCSVI are much less prevalent than initially reported, and do not distinguish MS from other subjects. Our findings do not support the hypothesis that CCSVI is causally associated with MS.

Multidetector CT evaluation of active extravasation in blunt abdominal and pelvic trauma patients.

Timely localization of a bleeding source can improve the efficacy of trauma management, and improvements in the technology of computed tomography (CT) have expedited the work-up of the traumatized patient. The classic pattern of active extravasation (ie, administered contrast agent that has escaped from injured arteries, veins, or urinary tract) at dual phase CT is a jet or focal area of hyperattenuation within a hematoma that fades into an enlarged, enhanced hematoma on delayed images. This finding indicates significant bleeding and must be quickly communicated to the clinician, since potentially lifesaving surgical or endovascular repair may be necessary. Active extravasation can be associated with other injuries to arteries, such as a hematoma or a pseudoaneurysm. Both active extravasation and pseudoaneurysm (unlike bone fragments and dense foreign bodies) change in appearance on delayed images, compared with their characteristics on arterial images. Other clues to the location of vessel injury include lack of vascular enhancement (caused by occlusion or spasm), vessel irregularity, size change (such as occurs with pseudoaneurysm), and an intimal flap (which signifies dissection). The sentinel clot sign is an important clue for locating the bleeding source when other more localizing findings of vessel injury are not present. Timely diagnosis, differentiation of vascular injuries from other findings of trauma, signs of depleted intravascular volume, and localization of vascular injury are important to convey to interventional radiologists or surgeons to improve trauma management.

Interventional radiologic management of renal transplant dysfunction: indications, limitations, and technical considerations.

Renal transplantation is the treatment of choice for most patients with end-stage renal disease. However, in spite of continuous progress in surgical techniques and immunosuppressive therapy, a wide variety of vascular and nonvascular complications can arise postoperatively. Vascular complications include transplant renal artery stenosis, arteriovenous fistulas or intrarenal pseudoaneurysms following renal transplant biopsy, extrarenal pseudoaneurysms, and graft thrombosis. Nonvascular complications include urologic complications (eg, ureteral obstruction, urine leak) and perigraft fluid collections (eg, lymphocele, abscess, hematoma, urinoma). These postoperative complications can be diagnosed and managed with minimally invasive techniques; however, an understanding of renal transplant anatomy and the risks of posttransplantation immunosuppressive therapy unique to this patient population is essential to their successful application. In addition, familiarity with the indications for and limitations of these techniques as well as collaboration between the radiologist and the transplantation surgeon are vital for maximizing the chances of renal allograft survival.

Gastrointestinal complications associated with hepatic arterial Yttrium-90 microsphere therapy.

Hepatic arterial therapy with yttrium-90 microspheres exploits the avenue provided by the neoplastic microvasculature to deliver high-energy, low-penetrating therapeutic doses of radiation. Variant hepatic arterial anatomy, collateral vessels, and changes in flow dynamics during treatment can affect particle dispersion and lead to nontarget particle distribution and subsequent gastrointestinal morbidity. Awareness of these variances and techniques to prevent gastrointestinal tract microsphere delivery is essential in mitigating this serious complication. Our aim is to increase the understanding of the role of various imaging and preventative techniques in minimizing this undesired effect.

Endovascular and interventional procedures in obese patients: a review of procedural technique modifications and radiation management.

As the prevalence of obesity in the United States continues to increase, the volume of endovascular and fluoroscopically guided procedures is also increasing. With obese patients, it often seems the only consideration is whether the table weight tolerance can accommodate the patient. This is a naive approach to performing procedures in obese patients, as there are multiple considerations involved in providing state-of-the-art endovascular and interventional care to obese patients. A growing collection of literature is beginning to surface regarding the appropriate modifications in the interventional care of these patients. This article reviews the relevant literature on this important subject.

Diagnosing traumatic arterial injury in the extremities with CT angiography: pearls and pitfalls.

Computed tomographic (CT) angiography is a reliable and convenient imaging modality for diagnosing arterial injuries after blunt and penetrating trauma to the extremities. It is a noninvasive modality that could replace conventional arteriography as the initial diagnostic study for arterial injuries after trauma to the extremities. The technique requires scanning with multidetector helical CT after rapid intravenous injection of iodinated contrast material. The CT angiographic signs of arterial injuries in the extremities are active extravasation of contrast material, pseudoaneurysm formation, abrupt narrowing of an artery, loss of opacification of a segment of artery, and arteriovenous fistula formation. Metallic streak artifact, motion artifact, and inadequate arterial opacification may render a CT angiogram nondiagnostic. Studies have shown the sensitivity of CT angiography to be 90%-95.1% and its specificity 98.7%-100% for detecting arterial injury to the extremities after trauma.