Publications

PURPOSE: Chiari malformation type I (CMI) patients have been independently shown to have both increased resistance to cerebrospinal fluid (CSF) flow in the cervical spinal canal and greater cardiac-induced neural tissue motion compared to healthy controls. The goal of this paper is to determine if a relationship exists between CSF flow resistance and brain tissue motion in CMI subjects.

METHODS: Computational fluid dynamics (CFD) techniques were employed to compute integrated longitudinal impedance (ILI) as a measure of unsteady resistance to CSF flow in the cervical spinal canal in thirty-two CMI subjects and eighteen healthy controls. Neural tissue motion during the cardiac cycle was assessed using displacement encoding with stimulated echoes (DENSE) magnetic resonance imaging (MRI) technique.

RESULTS: The results demonstrate a positive correlation between resistance to CSF flow and the maximum displacement of the cerebellum for CMI subjects (r = 0.75, p = 6.77 × 10-10) but not for healthy controls. No correlation was found between CSF flow resistance and maximum displacement in the brainstem for CMI or healthy subjects. The magnitude of resistance to CSF flow and maximum cardiac-induced brain tissue motion were not statistically different for CMI subjects with and without the presence of five CMI symptoms: imbalance, vertigo, swallowing difficulties, nausea or vomiting, and hoarseness.

CONCLUSION: This study establishes a relationship between CSF flow resistance in the cervical spinal canal and cardiac-induced brain tissue motion in the cerebellum for CMI subjects. Further research is necessary to understand the importance of resistance and brain tissue motion in the symptomatology of CMI.

PURPOSE: To assess the feasibility and safety of using computed tomography (CT) guidance for ablation of prostate cancer in the salvage setting.

MATERIALS AND METHODS: This institutional review board-approved retrospective study of consecutive patients who presented with prostate cancer recurrence and underwent percutaneous CT-guided cryoablation was conducted between July 2020 and September 2022. A total of 18 patients met the inclusion criteria, and a total of 19 procedures were performed. Demographic details; preablation and postablation urinary, rectal, and erectile function assessment; procedure details; and preoperative and postoperative imaging findings and prostate-specific antigen (PSA) values were recorded.

RESULTS: The mean treated tumor size was 15.7 mm ± 6.2. Technical success was achieved in 18 of the 19 procedures (94.7%), with 1 procedure aborted due to inability to obtain a safe plane. The mean follow-up time was 10.0 months (range, 2.3-26.7 months) at the time of manuscript preparation. The mean PSA before ablation was 8.1 ng/mL ± 9.3, and postablation PSA nadir was 2.6 ng/mL ± 4.0 (P = .002). Of the 18 patients who had postoperative imaging, 16 (88.9%) had a complete response (ie, no evidence of residual disease), and 2 (11.1%) patients had residual disease. Overall, 16 (88.9%) of the 18 treated patients demonstrated a PSA and/or imaging response to ablation. Mild adverse events occurred in 4 (22%) of the 18 cases.

CONCLUSIONS: CT-guided cryoablation appears to be a technically feasible, safe option for treating locally recurrent prostate cancer.

BACKGROUND: Routine concordance evaluation between pathology and imaging findings was introduced for CT-guided biopsies.

PURPOSE: To analyze malignancy rate in concordant, discordant, and indeterminate non-malignant results of CT-guided lung biopsies.

METHODS: Concordance between pathology results and imaging findings of consecutive patients undergoing CT-guided lung biopsy between 7/1/2016 and 9/30/2021 was assessed during routine meetings by procedural radiologists. Concordant was defined as pathology consistent with imaging findings; discordant was used when pathology could not explain imaging findings; indeterminate when pathology could explain imaging findings but there was concern for malignancy. Recommendations for discordant and indeterminate were provided. All the malignant results were concordant. Pathology of repeated biopsy, surgical sample, or follow-up was considered reference standard.

RESULTS: Consecutive 828 CT-guided lung biopsies were performed on 795 patients (median age 70 years, IQR 61-77), 423/828 (51%) women. On pathology, 224/828 (27%) were non-malignant. Among the non-malignant, radiology-pathology concordance determined 138/224 (62%) to be concordant with imaging findings, 54/224 (24%) discordant, and 32/224 (14%) indeterminate. When compared to the reference standard, 33/54 (61%) discordant results, 6/30 (20%) indeterminate, and 3/133 (2%) concordant were malignant. The prevalence of malignancy in the three groups was significantly different (p < 0.001). Time to diagnosis was significantly different between patients who reached the diagnosis with imaging follow-up (median 114 days, IQR 69-206) compared to repeat biopsy (33 days, IQR 18-133) (p = 0.01).

CONCLUSION: Routine radiology-pathology concordance evaluation of CT-guided lung biopsy correctly identifies patients at high risk for missed diagnosis of malignancy. Repeat biopsy is the fastest method to reach diagnosis.

CLINICAL RELEVANCE STATEMENT: A routine radiology-pathology concordance assessment identifies patients with non-malignant CT-guided lung biopsy result who are at greater risk of missed diagnosis of malignancy.

KEY POINTS: • A routine radiology-pathology concordance evaluation of CT-guided lung biopsies classified 224 non-malignant results as concordant, discordant, or indeterminate. • The percentage of malignancy on follow-up was significantly different in concordant (2%), discordant (61%), and indeterminate (20%) (p < 0.001). • Time to definitive diagnosis was significantly shorter with repeat biopsy (33 days), compared to imaging follow-up (114 days), p = 0.01.

PURPOSE: To characterize intratumoral immune cell trafficking in ablated and synchronous tumors following combined radiofrequency ablation (RFA) and systemic liposomal granulocyte-macrophage colony stimulation factor (lip-GM-CSF).

METHODS: Phase I, 72 rats with single subcutaneous R3230 adenocarcinoma were randomized to 6 groups: a) sham; b&c) free or liposomal GM-CSF alone; d) RFA alone; or e&f) combined with blank liposomes or lip-GM-CSF. Animals were sacrificed 3 and 7 days post-RFA. Outcomes included immunohistochemistry of dendritic cells (DCs), M1 and M2 macrophages, T-helper cells (Th1) (CD4+), cytotoxic T- lymphocytes (CTL) (CD8+), T-regulator cells (T-reg) (FoxP3+) and Fas Ligand activated CTLs (Fas-L+) in the periablational rim and untreated index tumor. M1/M2, CD4+/CD8+ and CD8+/FoxP3+ ratios were calculated. Phase II, 40 rats with double tumors were randomized to 4 groups: a) sham, b) RFA, c) RFA-BL and d) RFA-lip-GM-CSF. Synchronous untreated tumors collected at 7d were analyzed similarly.

RESULTS: RFA-lip-GMCSF increased periablational M1, CTL and CD8+/FoxP3+ ratio at 3 and 7d, and activated CTLs 7d post-RFA (p<0.05). RFA-lip-GMSCF also increased M2, T-reg, and reduced CD4+/CD8+ 3 and 7d post-RFA respectively (p<0.05). In untreated index tumor, RFA-lip-GMCSF improved DCs, M1, CTLs and activated CTL 7d post-RFA (p<0.05). Furthermore, RFA-lip-GMSCF increased M2 at 3 and 7d, and T-reg 7d post-RFA (p<0.05). In synchronous tumors, RFA-BL and RFA-lip-GM-CSF improved DC, Th1 and CTL infiltration 7d post-RFA.

CONCLUSION: Systemic liposomal GM-CSF combined with RFA improves intratumoral immune cell trafficking, specifically populations initiating (DC, M1) and executing (CTL, FasL+) anti-tumor immunity. Moreover, liposomes influence synchronous untreated metastases increasing Th1, CTL and DCs infiltration.

OBJECTIVES: To determine the factors that affect successful ultrasound-guided biopsy of liver lesions and build a model predicting feasibility of US-guided liver biopsy.

METHODS: This is IRB-approved HIPAA-compliant retrospective review of consecutive ultrasound-guided targeted liver biopsies performed or attempted between 1/2018 and 9/2020 at a single tertiary academic institution with a total of 501 patients included. Mann-Whitney and chi-square tests were used to compare continuous and categorical variables, respectively. Logistic regression model was built to predict feasibility of successful ultrasound-guided biopsy.

RESULTS: Liver lesion biopsy was successfully performed with US guidance in 429/501 (86%) patients. Lesions not amenable for US biopsy were smaller (median size 1.6 cm vs 3.3 cm, p < 0.0001) and deeper within the liver (median depth 9.0 cm vs 5.8 cm, p < 0.0001). The technical success rate was lowest for lesions in segment II (40/53, 75%), while lesions in segment IVb (87/91, 96%) had highest success rate (p < 0.003). US targeting in patients with 1 or 2 lesions was less feasible than in patients with 3 or more lesions, 126/180 (70%) vs. 303/321 (94%), (p < 0.0001). Model including lesion size, depth, location, and number of lesions predicts feasibility of US-guided biopsy with Area under the ROC curve (AUC) = 0.92.

CONCLUSIONS: Linear logistic regression model that includes lesion size, depth and location, and number of lesions is highly successful in predicting feasibility of ultrasound-guided biopsy for liver lesions. Smaller lesions, deeper lesions, and lesions in segment II and VIII in patients with less than 3 lesions were less feasible for ultrasound-guided biopsy of liver lesions.

PURPOSE: There are limited existing data on the lymphatic anatomy of patients with primary lymphedema (LED), which is caused by aberrant development of lymphatic channels. In addition, there is a paucity of contemporary studies that use groin intranodal lymphangiography (IL) to evaluate LED anatomy. The purpose of this retrospective observational study was to better delineate the disease process and anatomy of primary LED using groin IL.

MATERIALS AND METHODS: We identified common groin IL findings in a cohort of 17 primary LED patients performed between 1/1/2017 and 1/31/2022 at a single institution. These patients were clinically determined to have primary lymphedema and demonstrated associated findings on lower extremity MR and lymphoscintigraphy.

RESULTS: Ten patients (59%) demonstrated irregular lymph node morphology or a paucity of lymph nodes on the more symptomatic laterality. Eight patients (47%) demonstrated lymphovenous shunting from pre-existing anastomoses between the lymphatic and venous systems. Eight patients (47%) demonstrated passage of contrast past midline to the contralateral lymphatics. Finally, 12 patients (71%) failed to opacify the cisterna chyli and thoracic duct on their initial lymphangiograms. Delayed computed tomography of 3 patients showed eventual central lymphatic opacification up to the renal veins, but none of these patients showed central lymphatic opacification to the thorax.

CONCLUSION: This descriptive, exploratory study demonstrates common central groin IL findings in primary LED to highlight patterns interventional radiologists should identify and report when addressing primary LED.