Safety outcomes and improvement in pain scores after radiologist-performed fluoroscopy-guided interlaminar cervical epidural steroid injection.

INTRODUCTION: Image-guided spine injections are an important tool in the management of patients with a variety of spinal pathologies. Our practice offers radiologist-performed fluoroscopy-guided interlaminar cervical epidural steroid injection (ESI) routinely performed in the outpatient setting. The purpose of this study was to evaluate clinical outcomes and improvement in pain scores after radiologist-performed cervical ESI. METHODS: An institutional database was used to retrospectively identify cervical injections performed between October 2016 and October 2022. All injections were performed at the C7-T1 level utilizing 1.0 mL of 10 mg/mL dexamethasone without epidural anesthetic. The Numerical Rating Scale (NRS) was used to assess pain improvement. Cervical MRI was reviewed to assess pre-injection cervical disease severity. Patient charts were reviewed for any post-injection complications. RESULTS: A total of 251 cervical injections in 186 patients met our inclusion criteria with mean clinical follow up of 28.5 months (range 0.2 - 73.0 months). No patients experienced any major complications after injection. Post-injection pain scores were available for 218 of 251 injections (86.9%) with mean follow-up of 11.8 days (range 6 - 57 days). There was a significant improvement in pain scores from a mean pre-injection NRS score of 5.2/10 to 3.0/10 (p < .0001). 117 patients (53.7%) reported ≥ 50% improvement after injection. Patients who had prior injection were more likely to report ≥ 50% pain improvement after subsequent injection (p = .012). CONCLUSION: Radiologist-performed fluoroscopy-guided interlaminar cervical ESI at the C7-T1 level is a safe and effective tool in the management of patients with cervical pathology.

Von Hippel-Lindau Disease (VHL): Characteristic Lesions with Classic Imaging Findings.

Von Hippel-Lindau disease (VHL) is a multisystem cancer syndrome caused by the inactivation of the VHL tumor suppressor gene and involves various organ systems including the central nervous system (CNS), endocrine system, and the kidneys. Tumors seen in patients with VHL disease can be benign or malignant and are usually multifocal, bilateral, and hypervascular in nature. As most lesions associated with VHL are asymptomatic initially, early diagnosis and the institution of an evidence-based surveillance protocol are of paramount importance. Screening, surveillance, and genetic counseling are key aspects in the management of patients diagnosed with VHL disease and often require a multidisciplinary approach and referral to specialized centers. This article will discuss the characteristic lesions seen with VHL disease, their diagnosis, screening protocols and management strategies, as well as an illustrative case to demonstrate the natural progression of the disease with classic imaging findings.

MRI features associated with HCC histologic subtypes: a western American and European bicenter study.

OBJECTIVES: To evaluate if preoperative MRI can predict the most frequent HCC subtypes in North American and European patients treated with surgical resection. METHODS: A total of 119 HCCs in 97 patients were included in the North American group and 191 HCCs in 176 patients were included in the European group. Lesion subtyping was based on morphologic features and immuno-histopathological analysis. Two radiologists reviewed preoperative MRI and evaluated the presence of imaging features including LI-RADS major and ancillary features to identify clinical, biologic, and imaging features associated with the main HCC subtypes. RESULTS: Sixty-four percent of HCCs were conventional. The most frequent subtypes were macrotrabecular-massive (MTM-15%) and steatohepatitic (13%). Necrosis (OR = 3.32; 95% CI: 1.39, 7.89; p = .0064) and observation size (OR = 1.011; 95% CI: 1.0022, 1.019; p = .014) were independent predictors of MTM-HCC. Fat in mass (OR = 15.07; 95% CI: 6.57, 34.57; p < .0001), tumor size (OR = 0.97; 95% CI: 0.96, 0.99; p = .0037), and absence of chronic HCV infection (OR = 0.24; 95% CI: 0.084, 0.67; p = .0068) were independent predictors of steatohepatitic HCC. Independent predictors of conventional HCCs were viral C hepatitis (OR = 3.20; 95% CI: 1.62, 6.34; p = .0008), absence of fat (OR = 0.25; 95% CI: 0.12, 0.52; p = .0002), absence of tumor in vein (OR = 0.34; 95% CI: 0.13, 0.84; p = .020), and higher tumor-to-liver ADC ratio (OR = 1.96; 95% CI: 1.14, 3.35; p = .014) CONCLUSION: MRI is useful in predicting the most frequent HCC subtypes even in cohorts with different distributions of liver disease etiologies and tumor subtypes which might have future treatment and management implications. KEY POINTS: • Representation of both liver disease etiologies and HCC subtypes differed between the North American and European cohorts of patients. • Retrospective two-center study showed that liver MRI is useful in predicting the most frequent HCC subtypes.

Sural nerve: imaging anatomy and pathology.

High resolution ultrasound (US) and magnetic resonance (MR) neurography are both imaging modalities that are commonly used for assessing peripheral nerves including the sural nerve (SN). The SN is a cutaneous sensory nerve which innervates the lateral ankle and foot to the base of the fifth metatarsal. It is formed by contributing nerves from the tibial and common peroneal nerves with six patterns and multiple subtypes described in literature. In addition to the SN being a cutaneous sensory nerve, the superficial location enables the nerve to be easily biopsied and harvested for a nerve graft, as well as increasing the susceptibility to traumatic injury. As with any peripheral nerves, pathologies such as peripheral nerve sheath tumors and neuropathies can also affect the SN. By utilizing a high frequency probe in US and high-resolution MR neurography, the SN can be easily identified even with the multiple variations given the standard distal course. US and MRI are also useful in determining pathology of the SN given the specific image findings that are seen with peripheral nerves. In this review, we evaluate the normal imaging anatomy of the SN and discuss common pathologies identified on imaging.

MRA of the Supraaortic Vasculature: Comparison of Gadobutrol and Gadoterate Meglumine at 1.5 T.

BACKGROUND: Gadobutrol (GB) and gadoterate meglumine (GM) are contrast agents used for contrast-enhanced magnetic resonance angiography (CEMRA). Supraaortic vasculature (SAV) CEMRAs are used to evaluate stroke risk and neurologic symptoms. There is a need to compare the SAV CEMRA image quality obtained with GB and GM. PURPOSE: To intra-individually compare MRA images obtained with equimolar GB and GM at 1.5 T in the SAV. STUDY TYPE: Prospective, crossover. POPULATION: Twenty-eight subjects (54 ± 13 years; 17 female). FIELD STRENGTH/SEQUENCE: 1.5 T; three-dimensional (3D) gradient recalled echo. ASSESSMENT: Quantitative image quality was measured by normalized signal intensity (SIn ) [SIn  = SI blood/SD blood] and contrast ratio (CR) [CR = SI blood/SI muscle], determined by an observer (JWC) with 1 year of vascular imaging experience. Three radiologists (AS, PA, and MU) with (5, 5, and 6 years of) vascular imaging experience evaluated image quality by Likert-scale ratings (of image impression, wall conspicuity, and artifact absence). STATISTICAL TESTS: SIn and CR were compared with paired t-tests or Wilcoxon signed-rank tests and Bland-Altman plots. Qualitative ratings were compared with Wilcoxon signed-rank test. RESULTS: No significant difference in SIn was found between GB and GM. CRs with GB were significantly higher than GM at the right common carotid (6.9 ± 2.5 vs. 4.8 ± 1), left internal carotid (7.3 ± 2 vs. 4.4 ± 1.2), right internal carotid (7.7 ± 2.2 vs. 5 ± 1.1), and left vertebral (6.6 ± 2.2 vs. 4.5 ± 1.1) arteries. Bland-Altman plots showed relatively greater differences between GB and GM at higher CRs and SIn s. GM showed significantly higher artifact than GB (3.56 ± 0.52 vs. 3.36 ± 0.46) and significantly lower overall image quality (10.73 ± 1.45 vs. 11.26 ± 1.58) at the left vertebral artery. DATA CONCLUSION: At 1.5 T and equimolar demonstration, GB (0.1 mL/kg, i.e., 0.1 mmol/kg) showed higher CRs in the SAV compared to GM (0.2 mL/kg, i.e., 0.1 mmol/kg) at most vessels. Subjective image quality was not significantly different between the two agents for most vessels. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

MRI evaluation of solid soft tissue masses of the fingers with pathology correlation.

OBJECTIVE: Space occupying lesions of the fingers are commonly encountered in clinical and radiology practice. The objective of this study was to determine the characteristics of these lesions on MRI and to correlate with surgical pathology results. MATERIAL AND METHODS: This IRB-approved HIPAA-compliant study retrospectively evaluated the clinical, imaging and pathology findings of 100 consecutive patients referred for evaluation of solid soft tissue masses of the fingers. Only solid lesions with MR imaging prior to surgery were included in this study. MR images and when available corresponding radiographs were evaluated by two radiologist in regard to signal characteristics, relation to surrounding structures and enhancement. All masses were classified into different groups based on pathology results. RESULTS: Tenosynovial giant cell tumor (TSGCT) and fibroma of the tendon sheath were the most common solid tumors (36 %) and malignant tumors represent only 5% of the cohort. 70 % of masses with low T2 signal were TSGCT and fibroma of tendon sheath; 100 % of masses with peripheral high T2 signal and central low T2 signal/thrombus were vascular lesions, representing 41 % of the total vascular lesions in the cohort. Additionally, 100 % of serpiginous/tubular shaped masses were vascular lesions and 67 % of masses with infiltrative borders were malignant masses. Enhancement was important in identifying solid lesions but there was no statistical difference between groups related to enhancement pattern. There was a good agreement for all analyses between both readers. CONCLUSION: Typical MR findings can help to narrow the differential diagnosis in the evaluation of finger masses and provide crucial information to guide further management.

Radial-based acquisition strategies for pre-procedural non-contrast cardiovascular magnetic resonance angiography of the pulmonary veins.

BACKGROUND: Computed tomography angiography (CTA) or contrast-enhanced (CE) cardiovascular magnetic resonance angiography (CMRA) is often obtained in patients with atrial fibrillation undergoing evaluation prior to pulmonary vein (PV) isolation. Drawbacks of CTA include radiation exposure and potential risks from iodinated contrast agent administration. Free-breathing 3D balanced steady-state free precession (bSSFP) Non-contrast CMRA is a potential imaging option, but vascular detail can be suboptimal due to ghost artifacts and blurring that tend to occur with a Cartesian k-space trajectory or, in some cases, inconsistent respiratory gating. We therefore explored the potential utility of both breath-holding and free-breathing non-contrast CMRA, using radial k-space trajectories that are known to be less sensitive to flow and motion artifacts than Cartesian. MAIN BODY: Free-breathing 3D Cartesian and radial stack-of-stars acquisitions were compared in 6 healthy subjects. In addition, 27 patients underwent CTA and non-contrast CMRA for PV mapping. Three radial CMR acquisition strategies were tested: (1) breath-hold (BH) 2D radial bSSFP (BH-2D); (2) breath-hold, multiple thin-slab 3D stack-of-stars bSSFP (BH-SOS); and (3) navigator-gated free-breathing (FB) 3D stack-of-star bSSFP using a spatially non-selective RF excitation (FB-NS-SOS). A non-rigid registration algorithm was used to compensate for variations in breath-hold depth. In healthy subjects, image quality and vessel sharpness using a free-breathing 3D SOS acquisition was significantly better than free-breathing (FB) Cartesian 3D. In patients, diagnostic image quality was obtained using all three radial CMRA techniques, with BH-SOS and FB-NS-SOS outperforming BH-2D. There was overall good correlation for PV maximal diameter between BH-2D and CTA (ICC = 0.87/0.83 for the two readers), excellent correlation between BH-SOS and CTA (ICC = 0.90/0.91), and good to excellent correlation between FB-NS-SOS and CTA (ICC = 0.87/0.94). For PV area, there was overall good correlation between BH-2D and CTA (ICC = 0.79/0.83), good to excellent correlation between BH-SOS and CTA (ICC = 0.88/0.91) and excellent correlation between FB-NS-SOS and CTA (ICC = 0.90/0.95). CNR was significantly higher with BH-SOS (mean = 11.04) by comparison to BH-2D (mean = 6.02; P = 0.007) and FB-NS-SOS (mean = 5.29; P = 0.002). CONCLUSION: Our results suggest that a free-breathing stack-of-stars bSSFP technique is advantageous in providing accurate depiction of PV anatomy and ostial measurements without significant degradation from off-resonance artifacts, and with better image quality than Cartesian 3D. For patients in whom respiratory gating is unsuccessful, a breath-hold thin-slab stack-of-stars technique with retrospective motion correction may be a useful alternative.

The abrupt pancreatic duct cutoff sign on MDCT and MRI.

PURPOSE: To evaluate the pancreatic duct cutoff sign in detecting pancreatic adenocarcinoma using CT and MRI. METHODS: A retrospective analysis of patients with a pancreatic duct (PD) cutoff sign on CT or MRI from 2000 to 2019 was performed. The primary outcome measured was the presence or absence of a malignant pancreatic tumor. Variables evaluated included imaging characteristics of patients with a malignant versus non-malignant cause of duct cutoff and included PD size and PD-to-parenchyma ratio, contour abnormality, abnormal enhancement, diffusion abnormality, and upstream parenchymal atrophy. RESULTS: Seventy-two patients (44:28 M:F, mean age 64 years) were identified with a PD cutoff sign. Fifty-eight percent (42/72) of these patients were diagnosed with malignancy, 62% (26/42) of whom were diagnosed with pancreatic ductal adenocarcinoma. In patients diagnosed with a non-malignant cause of duct cutoff, 37% (11/30) were diagnosed with chronic pancreatitis. Eighty-eight percent (37/42) of patients with malignant causes and 33% (10/30) of patients with non-malignant causes were noted to have an associated mass on imaging. The presence of contour abnormality, diffusion abnormality, or abnormal enhancement at the level of the pancreatic cutoff was significantly higher in patients with malignancy (p < 0.05). There was no difference between groups in location of the pancreatic duct cutoff, degree of pancreatic duct dilatation, PD-to-parenchyma ratio, or presence of upstream atrophy. CONCLUSION: Abrupt cutoff of the pancreatic duct was associated with an increased likelihood of detecting malignancy. All patients who demonstrate this sign should undergo expedited workup with dedicated MRI and EUS with biopsy.

Ethylene Vinyl Alcohol Copolymer Embolization for Acute Renal Hemorrhage: Initial Experience in 24 Cases.

OBJECTIVE. The purpose of this study was to assess the efficacy and safety of ethylene vinyl alcohol (EVOH) copolymer (Onyx, Medtronic) for embolization for acute renal hemorrhage. MATERIALS AND METHODS. Between October 2006 and June 2018, 24 consecutive patients were treated by embolization with EVOH copolymer for acute renal hemorrhage at Hôpital Bichat-Claude-Bernard. CT angiography was performed in all patients before treatment. Technical success was defined as the complete occlusion of the bleeding artery on final renal angiogram. Clinical success was defined as the absence of rebleeding after embolization. Complications mid procedure, infarcted renal area on final angiogram, and renal function 1 week after embolization were retrospectively analyzed. RESULTS. Active bleeding was observed in all cases. The causes of acute renal hemorrhage were iatrogenic in 12 patients, vascular malformation in four patients, renal tumor in four patients, and unknown in four patients. EVOH copolymer was the sole embolic agent used in 16 patients. In eight patients, EVOH copolymer was used after persistent bleeding after embolization with coils. Technical and clinical success rates were 100%. No patient required surgery or new embolization during a mean follow-up period of 35 months (range, 6-86 months). No serious complications were attributable to EVOH copolymer. The mean infarcted renal area was 10% (range, 5-30%). Renal function, available for 16 (67%) patients, was not altered 1 week after embolization. CONCLUSION. EVOH copolymer is safe and effective for embolization of acute renal hemorrhage, either as a first-line embolic agent or after failure of coil embolization.