Publications

RATIONALE AND OBJECTIVES: The COVID-19 pandemic has caused much uncertainty and disruption in healthcare resulting in many challenges for strategic planning. Scenario planning is a tool that allows healthcare leaders to plan healthcare delivery strategies by incorporating the uncertainties into the analysis and planning process.

MATERIALS AND METHODS: Variables were identified which will have major impact on the future, but whose future direction is uncertain. The extremes of these drivers were used to generate multiple scenarios. A subset of scenarios was used to evaluate potential tactics to determine which may be high yield in the face of uncertainty.

RESULTS: Unlike traditional strategic planning, scenario planning does not develop a single future with a path to that future. Scenario planning evaluates tactics to determine which would be helpful in specific scenarios, multiple different futures or under specific conditions.

CONCLUSION: We present a scenario planning model which can be used to determine specific tactics to accommodate the uncertainty due to variable healthcare delivery needs in the COVID-19 era.

AIM: To determine the causes and diagnostic utility of musculoskeletal (MSK) magnetic resonance imaging (MRI) recall examinations.

MATERIALS AND METHODS: An institutional review board-approved retrospective review was conducted of all MSK MRI examinations performed at a single academic institution over 10 years where radiologists requested the patient return for additional imaging. The reason for the recall was documented. Recalls were reviewed in consensus by two MSK radiologists to determine whether additional sequences resulted in a change in the final report. Recall causes were divided into four categories: (1) radiologist-related: incorrect field of view (FOV) or incorrect protocol; (2) technologist-related: incorrect FOV or incorrect/incomplete protocol performed, or technically poor-quality images; (3) patient-related motion artefact; (4) unexpected lesion discovered. Fisher's exact test was used to assess for statistical significance.

RESULTS: The recall rate was 0.25% (156/62,930). Of the total 129 recalls returning for imaging, 42 (33%) were radiologist-related, 45 (35%) were technologist-related, six (5%) were patient-related, and 36 (28%) had an unexpected lesion requiring additional sequences. For clinical utility, 42% resulted in a change from the initial report. Recalls due to radiologist error, incorrect FOV, or unexpected lesion caused a significant change in the final report; however, recalls due to technologist error, patient motion artefact, or incorrect protocol did not.

CONCLUSION: MRI MSK recalls are uncommon, and the most common reasons are incorrect FOV, incorrect protocol, and unexpected lesion. Radiologist-related errors in protocols and FOV led to a significant change in the final report and should be targeted as areas for improvement to reduce recall examinations.

Malignant pleural mesothelioma (MPM) is an aggressive primary malignancy of the pleura that presents unique radiologic challenges with regard to accurate and reproducible assessment of disease extent at staging and follow-up imaging. By optimizing and harmonizing technical approaches to imaging MPM, the best quality imaging can be achieved for individual patient care, clinical trials, and imaging research. This consensus statement represents agreement on harmonized, standard practices for routine multimodality imaging of MPM, including radiography, computed tomography, 18F-2-deoxy-D-glucose positron emission tomography, and magnetic resonance imaging, by an international panel of experts in the field of pleural imaging assembled by the International Mesothelioma Interest Group. In addition, modality-specific technical considerations and future directions are discussed. A bulleted summary of all technical recommendations is provided.

PURPOSE: Substantial variation in imaging terms used to describe the adrenal gland and adrenal findings leads to ambiguity and uncertainty in radiology reports and subsequently their understanding by referring clinicians. The purpose of this study was to develop a standardized lexicon to describe adrenal imaging findings at CT and MRI.

METHODS: Fourteen members of the Society of Abdominal Radiology adrenal neoplasm disease-focused panel (SAR-DFP) including one endocrine surgeon participated to develop an adrenal lexicon using a modified Delphi process to reach consensus. Five radiologists prepared a preliminary list of 35 imaging terms that was sent to the full group as an online survey (19 general imaging terms, 9 specific to CT, and 7 specific to MRI). In the first round, members voted on terms to be included and proposed definitions; subsequent two rounds were used to achieve consensus on definitions (defined as ≥ 80% agreement).

RESULTS: Consensus for inclusion was reached on 33/35 terms with two terms excluded (anterior limb and normal adrenal size measurements). Greater than 80% consensus was reached on the definitions for 15 terms following the first round, with subsequent consensus achieved for the definitions of the remaining 18 terms following two additional rounds. No included term had remaining disagreement.

CONCLUSION: Expert consensus produced a standardized lexicon for reporting adrenal findings at CT and MRI. The use of this consensus lexicon should improve radiology report clarity, standardize clinical and research terminology, and reduce uncertainty for referring providers when adrenal findings are present.

BACKGROUND. Complete pathologic necrosis (CPN) is associated with improved survival in patients who undergo liver transplant (LT) after locoregional therapy (LRT) for hepatocellular carcinoma (HCC). OBJECTIVE. The purpose of this article was to identify patient, HCC, and transplant center characteristics associated with rates of CPN on explant evaluation using a large national sample of patients undergoing LT after LRT for HCC measuring 3 cm or smaller. METHODS. This retrospective study used data from the United Network for Organ Sharing database. The study included 6265 adults (median age, 62 years; 1505 women, 4760 men) who underwent LT after a single type of LRT (either transarterial chemoembolization [TACE], thermal ablation, or transarterial radioembolization [TARE]) for HCCs measuring 3 cm or smaller at one of 118 U.S. transplant centers from April 12, 2012, to March 31, 2020. Patients were classified as having CPN if explant evaluation showed 100% necrosis of all HCCs. Associations with CPN were explored. Centers were categorized into tertiles on the basis of center-level CPN rates, and tertiles were compared. RESULTS. LRT was performed by TACE in 69.5% (4352/6265), thermal ablation in 19.4% (1217/6265), and TARE in 11.1% (696/6265) of patients. CPN rate was 18.5% (805/4352) after TACE, 35.8% (436/1217) after thermal ablation, 33.6% (234/696) after TARE, and 23.5% (1475/6265) overall. In multivariable analysis incorporating age, sex, model for end-stage liver disease score, α-fetoprotein level before LRT, wait list time, number of HCCs, HCC size, and the transplant center (as a random factor), use of thermal ablation (OR, 2.19; 95% CI, 1.86-2.57; p < .001) or TARE (OR, 1.92; 95% CI, 1.57-2.36; p < .001), with TACE as reference, independently predicted greater likelihood of CPN. Center-level CPN rates ranged from 0.0% to 50.0%. With centers stratified by CPN rates, ablation was performed more frequently than TACE in 5.0% of centers in the first, 15.4% in the second, and 23.1% in the third tertiles (p = .07). CONCLUSION. CPN rate on explant evaluation was low. Thermal ablation or TARE, rather than TACE, was associated with higher likelihood of CPN in patient-level and center-level analyses. CLINICAL IMPACT. Findings from this large national sample support a potential role of thermal ablation or TARE for achieving CPN of HCC measuring 3 cm or smaller.

PURPOSE: To assess technical feasibility and safety of portal vein thrombectomy with suction thrombectomy using a large-bore thrombectomy device for portomesenteric venous thrombosis (PMVT).

MATERIALS AND METHODS: After receiving approval from institutional review board, patients undergoing PMVT treatment using a large-bore aspiration thrombectomy device (Inari FlowTriever or ClotTriever) between July 2019 and June 2021 were identified at 2 medical centers. Charts were reviewed for demographic information, imaging findings, and procedural details. PMVT was categorized using the Yerdel grading system. The thrombectomy procedure was performed via transjugular access through the existing or a new transjugular intrahepatic portosystemic shunt (TIPS) or transsplenic or transhepatic approach. Technical success was defined as successful clot reduction and restoration of portal venous flow at the conclusion of the procedure. Patient outcomes based on clinical presentation, adverse events, and thrombectomy-associated adverse events were recorded.

RESULTS: Twenty patients, with a median age of 58 years (range, 23-72 years), underwent large-bore aspiration thrombectomy, which was technically successful in 19 of 20 (95%) patients. In 9 of 20 (45%) patients, 9 of 20 (45%) patients, and 2 of 20 (10%) patients, the 20-F, 16-F, and 24-F devices were used, respectively. Fourteen patients had a pre-existing TIPS, and 6 patients had a TIPS created. In 5 of 20 (25%) patients, overnight lysis was performed in conjunction with Inari thrombectomy. Thrombus resolution with restoration of flow was achieved in 19 of 20 (95%) cases. There were no thrombectomy-associated adverse events. The mean follow-up time was 70 days (±113) at which time primary patency of the portal venous system was present in 16 of 20 (80%) patients.

CONCLUSIONS: Large-bore aspiration portal vein thrombectomy is feasible for PMVT.

PURPOSE: To establish molecular magnetic resonance (MR) imaging instruments for in vivo characterization of the immune response to hepatic radiofrequency (RF) ablation using cell-specific immunoprobes.

MATERIALS AND METHODS: Seventy-two C57BL/6 wild-type mice underwent standardized hepatic RF ablation (70 °C for 5 minutes) to generate a coagulation area measuring 6-7 mm in diameter. CD68+ macrophage periablational infiltration was characterized with immunohistochemistry 24 hours, 72 hours, 7 days, and 14 days after ablation (n = 24). Twenty-one mice were subjected to a dose-escalation study with either 10, 15, 30, or 60 mg/kg of rhodamine-labeled superparamagnetic iron oxide nanoparticles (SPIONs) or 2.4, 1.2, or 0.6 mg/kg of gadolinium-160 (160Gd)-labeled CD68 antibody for assessment of the optimal in vivo dose of contrast agent. MR imaging experiments included 9 mice, each receiving 10-mg/kg SPIONs to visualize phagocytes using T2∗-weighted imaging in a horizontal-bore 9.4-T MR imaging scanner, 160Gd-CD68 for T1-weighted MR imaging of macrophages, or 0.1-mmol/kg intravenous gadoterate (control group). Radiological-pathological correlation included Prussian blue staining, rhodamine immunofluorescence, imaging mass cytometry, and immunohistochemistry.

RESULTS: RF ablation-induced periablational infiltration (206.92 μm ± 12.2) of CD68+ macrophages peaked at 7 days after ablation (P < .01) compared with the untreated lobe. T2∗-weighted MR imaging with SPION contrast demonstrated curvilinear T2∗ signal in the transitional zone (TZ) (186 μm ± 16.9), corresponsing to Iron Prussian blue staining. T1-weighted MR imaging with 160Gd-CD68 antibody showed curvilinear signal in the TZ (164 μm ± 3.6) corresponding to imaging mass cytometry.

CONCLUSIONS: Both SPION-enhanced T2∗-weighted and 160Gd-enhanced T1-weighted MR imaging allow for in vivo monitoring of macrophages after RF ablation, demonstrating the feasibility of this model to investigate local immune responses.

PURPOSE: The tricipital, or Caplan's, lymphatic pathway has been previously identified in cadavers and described as a potential compensatory pathway for lymphatic drainage of the upper extremity, as it may drain lymphatic fluid directly to the scapular lymph nodes, avoiding the axillary lymph node groups. The aim of this study was to map the anatomy of the tricipital pathway in vivo in patients without lymphatic disease.

METHODS: A retrospective review was performed to identify patients with unilateral breast cancer undergoing preoperative Indocyanine green (ICG) lymphography prior to axillary lymph node dissection from May 2021 through January 2022. Exclusion criteria were evidence or known history of upper extremity lymphedema or non-linear channels visualized on ICG. Demographic, oncologic, and ICG imaging data were extracted from a Lymphatic Surgery Database. The primary outcome of this study was the presence and absence of the tricipital pathway. The secondary outcome was major anatomical variations among those with a tricipital pathway.

RESULTS: Thirty patients underwent preoperative ICG lymphography in the study period. The tricipital pathway was visualized in the posterior upper arm in 90% of patients. In 63% of patients, the pathway had a functional connection to the forearm (long bundle variant) and in 27%, the pathway was isolated to the upper arm without a connection to the forearm (short bundle variant). In those with a long bundle, the contribution was predominantly from the posterior ulnar lymphosome. Anatomic destinations of the tricipital pathway included the deltotricipital groove and the medial upper arm channel, which drains to the axilla.

CONCLUSION: When present, the tricipital pathway coursed along the posterior upper arm with variability in its connections to the forearm distally, and the torso proximally. Long-term follow-up studies will help determine the significance of these anatomic variations in terms of individual risk of lymphedema after axillary nodal dissection.