Faculty Bibliography

BACKGROUND AND PURPOSE: To assess the sensitivity of non-localized, whole-head 1H-MRS to an individual's serial changes in total-brain NAA, Glx, Cr and Cho concentrations - metabolite metrics often used as surrogate markers in neurological pathologies. MATERIALS AND METHODS: In this prospective study, four back-to-back (single imaging session) and three serial (successive sessions) non-localizing, ~3min 1H-MRS (TE/TR/TI=5/104/940ms) scans were performed on 18 healthy young volunteers: 9 women, 9 men: 29.9+/-7.6 [mean+/-standard deviation (SD)] years old. These were analyzed by calculating a within-subject coefficient of variation (CV=SD/mean) to assess intra- and inter-scan repeatability and prediction intervals. This study was Health Insurance Portability and Accountability Act-compliant. All subjects gave Institutional Review Board-approved written, informed consent. RESULTS: The intra-scan CVs for the NAA, Glx, Cr and Cho were: 3.9+/-1.8%, 7.3+/-4.6%, 4.0+/-3.4% and 2.5+/-1.6%, and the corresponding inter-scan (longitudinal) values were: 7.0+/-3.1%, 10.6+/-5.6%, 7.6+/-3.5% and 7.0+/-3.9%. This method is shown to have 80% power to detect changes of 14%, 27%, 26% and 19% between two serial measurements in a given individual. CONCLUSIONS: Subject to the assumption that in neurological disorders NAA, Glx, Cr and Cho changes represent brain-only pathology and not muscles, bone marrow, adipose tissue or epithelial cells, this approach enables us to quantify them, thereby adding specificity to the assessment of the total disease load. This will facilitate monitoring diffuse pathologies with faster measurement, more extensive (~90%) spatial coverage and sensitivity than localized 1H-MRS.

PURPOSE: The purpose of this study was to evaluate the diagnostic performance of a "simulated" abbreviated MRI (AMRI) protocol using diffusion-weighted imaging (DWI) and T1-weighted (T1w) imaging obtained at the hepatobiliary phase (HBP) post gadoxetic acid injection alone and in combination, compared to dynamic contrast-enhanced (CE)-T1w imaging for the detection of hepatocellular carcinoma (HCC). METHODS: This was an IRB approved HIPAA compliant retrospective single institution study including patients with liver disease who underwent gadoxetic acid-enhanced MRI for HCC diagnosis. Three independent observers assessed 2 sets of images (full CE-set and AMRI including DWI+T1w-HBP). Diagnostic performance of T1w-HBP and DWI alone and in combination was compared to that of CE-set. All imaging sets included unenhanced T1w and T2w sequences. A preliminary analysis was performed to assess cost savings of AMRI protocol compared to a full MRI study. RESULTS: 174 patients including 62 with 80 HCCs were assessed. Equivalent per-patient sensitivity and negative predictive value (NPV) were observed for DWI (85.5% and 92.2%, pooled data) and T1w-HBP (89.8% and 94.2%) (P = 0.1-0.7), while these were significantly lower for the full AMRI protocol (DWI+T1w-HBP, 80.6% and 80%, P = 0.02) when compared to CE-set (90.3% and 94.9%). Higher specificity and positive predictive value were observed for CE-set vs. AMRI (P = 0.02). The estimated cost reduction of AMRI versus full MRI ranged between 30.7 and 49.0%. CONCLUSION: AMRI using DWI and T1w-HBP has a clinically acceptable sensitivity and NPV for HCC detection. This could serve as the basis for a future study assessing AMRI for HCC screening and surveillance.

PURPOSE: To compare background parenchymal enhancement (BPE) over time in patients with and without breast cancer. MATERIALS AND METHODS: This retrospective Institutional Review Board (IRB)-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant study included 116 women (25-84 years, mean 54 years) with breast cancer who underwent breast magnetic resonance imaging at 3T between 1/2/2009 and 12/29/2009 and 116 age and date-of-exam-matched women without breast cancer (23-84 years, mean 51 years). Two independent, blinded readers (R1, R2) recorded BPE (minimal, mild, moderate, marked) at three times (100, 210, and 320 seconds postcontrast). Subsequent cancers were diagnosed in 9/96 control patients with follow up (12.6-93.0 months, mean 63.6 months). Exact Mann-Whitney, Fisher's exact, and McNemar tests were performed. RESULTS: Mean BPE was not found to be different between patients with and without breast cancer at any time (P = 0.36-0.64). At time 2 as compared with time 1, there were significantly more patients, both with and without breast cancer, with BPE >minimal (R1: 90 vs. 41 [P < 0.001] and 81 vs. 36 [P < 0.001]; R2: 84 vs. 52 [P < 0.001] and 79 vs. 43 [P < 0.001]) and BPE >mild (R1: 59 vs. 10 [P < 0.001] and 47 vs. 13 [P < 0.001]; R2: 49 vs. 12 [P < 0.001] and 41 vs. 18 [P < 0.001]). BPE changes between times 2 and 3 were not significant (P = 0.083-1.0). Odds ratios for control patients developing breast cancer were significant only for R2 and ranged up to 7.67 (1.49, 39.5; P < 0.01) for BPE >mild at time 2. CONCLUSION: BPE changes between the first and second postcontrast scans and stabilizes thereafter in most patients. Further investigation into the most clinically relevant timepoint for BPE assessment is warranted. J. Magn. Reson. Imaging 2016.

BACKGROUND: Clinically significant anxiety and depression are common in patients with cancer, and are associated with poor psychiatric and medical outcomes. Historical and recent research suggests a role for psilocybin to treat cancer-related anxiety and depression. METHODS: In this double-blind, placebo-controlled, crossover trial, 29 patients with cancer-related anxiety and depression were randomly assigned and received treatment with single-dose psilocybin (0.3 mg/kg) or niacin, both in conjunction with psychotherapy. The primary outcomes were anxiety and depression assessed between groups prior to the crossover at 7 weeks. RESULTS: Prior to the crossover, psilocybin produced immediate, substantial, and sustained improvements in anxiety and depression and led to decreases in cancer-related demoralization and hopelessness, improved spiritual wellbeing, and increased quality of life. At the 6.5-month follow-up, psilocybin was associated with enduring anxiolytic and anti-depressant effects (approximately 60-80% of participants continued with clinically significant reductions in depression or anxiety), sustained benefits in existential distress and quality of life, as well as improved attitudes towards death. The psilocybin-induced mystical experience mediated the therapeutic effect of psilocybin on anxiety and depression. CONCLUSIONS: In conjunction with psychotherapy, single moderate-dose psilocybin produced rapid, robust and enduring anxiolytic and anti-depressant effects in patients with cancer-related psychological distress. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT00957359.

BACKGROUND AND PURPOSE: Clinical history is known to influence interpretation of a wide range of radiologic examinations. We sought to evaluate the influence of the clinical history on MRI interpretation of optic neuropathy. MATERIALS AND METHODS: 107 consecutive orbital MRI scans were retrospectively reviewed by three neuroradiologists. The readers independently evaluated the coronal STIR sequence for optic nerve hyperintensity and/or atrophy (yes/no) and the coronal post-contrast T1WI for optic nerve enhancement (yes/no). Readers initially evaluated the cases blinded to the clinical history. Following a two week washout period, readers again evaluated the cases with the clinical history provided. Inter-reader and reader-clinical radiologist agreement was assessed using Cohen's simple kappa coefficient. RESULTS: Intra-reader agreement, without and with provision of clinical history, was 0.564-0.716 on STIR and 0.270-0.495 on post-contrast T1WI. Inter-reader agreement was overall fair-moderate. On post-contrast T1WI, inter-reader agreement was significantly higher when the clinical history was provided (p = 0.001). Reader-clinical radiologist agreement improved with provision of the clinical history to the readers on both the STIR and post-contrast T1WI sequences. CONCLUSIONS: In the MRI assessment of optic neuropathy, only modest levels of inter-reader agreement were achieved, even after provision of clinical history. Provision of clinical history improved inter-reader agreement, especially when assessing for optic nerve enhancement. These findings confirm the subjective nature of orbital MRI interpretation in cases of optic neuropathy, and point to the importance of an accurate clinical history. Of note, the accuracy of orbital MRI in the context of optic neuropathy was not assessed, and would require further investigation.

BACKGROUND: There is substantial overlap between MRI of acute spinal cord lesions from neuromyelitis optica (NMO) and spinal cord infarct (SCI) in clinical practice. However, early differentiation is important since management approaches to minimize morbidity from NMO or SCI differ significantly. OBJECTIVE: To identify MRI features at initial presentation that may help to differentiate NMO acute myelitis from SCI. METHODS: 2 board-certified neuroradiologists, blinded to final diagnosis, retrospectively characterized MRI features at symptom onset for subjects with serologically-proven NMO (N=13) or SCI (N=11) from a single institution. Univariate and multivariate analyses were used to identify factors associated with NMO or SCI. RESULTS: SCI was more common in men and Caucasians, while NMO was more common in non-Caucasian women (P<0.05). MRI features associated with NMO acute myelitis (P<0.05) included location within 7-cm of cervicomedullary junction; lesion extending to pial surface; 'bright spotty lesions' on axial T2 MRI; and gadolinium enhancement. Patient's age, lesion length and cross-sectional area, cord expansion, and the "owl's eyes" sign did not differ between the two groups (P>0.05). CONCLUSION: Along with patient demographic characteristics, lesion features on MRI, including lesion location, extension to pial border and presence of 'bright spotty lesion' can help differentiate acute myelitis of NMO from SCI in the acute setting.

Purpose: To characterize the utility of shoulder imaging in the outpatient setting; Define predictor variables for useful shoulder imaging in terms of guiding the selection of the primary diagnosis and treatment Materials and Methods: We conducted a retrospective review of adult patients over a 32 month period evaluated and imaged for a primary complaint of shoulder pain in one of three outpatient settings: (1) orthopaedics, (2) emergency department [ED], and (3) internal medicine [IM]. Our sample population was chosen through a review of electronic medical records, using shoulder related ICD-9 codes and physician names. The main outcome variable for this study was imaging utility. A useful imaging examination was defined as a study that satisfied at least one of the following 4 criteria: changed the clinical diagnosis, guided a change in treatment selection, provided a final diagnosis, or guided definitive treatment. A utility score was assigned to each study based on the number of criteria satisfied (range 0-4) with a score of 0 defined as no utility, 1 low utility, 2 moderate utility, and score of > 3 high utility. For patients receiving multiple sequential imaging studies during their workup, each study was included and scored separately. The potential predictor variables evaluated for useful imaging included age, gender, trauma history, symptom chronicity, and injury setting (sports vs. non-sports). Statistical analysis included 95 % confidence intervals and binary logistic regression. Results: A total of 122 patients (70 female/52 male; mean age 47 years (range 18-84)) underwent a total of 171 imaging studies (109 radiographs/57 MRIs/3 CT/2 ultrasound) as part of their initial workup. 106 studies were ordered from orthopaedics, 64 from ED, and 1 from IM. CT and ultrasound utility were not assessed due to low number of cases. Overall, 95.9 % of the imaging studies met the minimum criteria for utility, most commonly helping guide the selection of a definitive treatment (71.9 %). 30.4 % of the studies were categorized as moderately useful, while 12.9 % were classified as highly useful. 95.4 % of radiographs met the criteria for utility, the majority of which were categorized as low utility (78.9 %). Both sports related injury history and trauma were predictive of at least moderate utility for radiographs (p = 0.039, p = 0.004). Younger age was a significant predictor of at least moderate utility for radiographs, most commonly in patients under 32 (p=0.003, AUC 0.748). 96.5 % of MRIs met the criteria for utility, the majority of which were categorized as moderate or high utility (84.2 %). None of the variables investigated were found to significantly predict MRI utility. For patients undergoing radiographs and MRI, MRI was found more useful than radiographs in 53 % of patients with an average utility score of 2.1. Equal utility was found in 42 % of cases, while radiographs were found most useful in 5 % of patients. Conclusion: Our study suggests that both radiographs and MRI have utility in the outpatient evaluation of shoulder pain. This serves as a potential first step towards the development of evidence based imaging algorithms that can be used and tested in future studies