MRI Indices of Glymphatic Function Correlate With Disease Duration in Idiopathic Intracranial Hypertension.

BACKGROUND: The glymphatic system represents an extravascular network of astrocytic channels responsible for interstitial fluid and solute transit through the brain parenchyma. Its dysfunction has been considered as a possible cause of idiopathic intracranial hypertension (IIH). METHODS: We enrolled participants with active IIH, treated or cured IIH, and controls. The active IIH group was divided into untreated participants with recently developed (<6 mo) and chronic (6+ mo) disease. Glymphatic function was assessed using diffusion tensor imaging along the paravascular space (DTI-ALPS) to generate an ALPS-index, hypothesized to measure glymphatic function. Participants were imaged before lumbar puncture (LP) if IIH was suspected and following LP when possible. RESULTS: ALPS indices were higher in participants with chronically present, active IIH than in those either with recently developed IIH or control participants. ALPS-indices correlated with papilledema but did not correlate significantly with age, BMI, or intracranial pressure (ICP). CONCLUSIONS: Our findings suggest that DTI-ALPS-indices of glymphatic function may be influenced by the chronicity of intracranial hypertension but do not support the hypothesis that glymphatic dysfunction causes IIH. Though these findings are preliminary, glymphatic imaging may be a useful radiographic biomarker in IIH.

Arterial Spin Labeling: Key Concepts and Progress Towards Use as a Clinical Tool.

Arterial spin labeling (ASL), a non-invasive MRI technique, has emerged as a valuable tool for researchers that can measure blood flow and related parameters. This review aims to provide a qualitative overview of the technical principles and recent developments in ASL and to highlight its potential clinical applications. A growing literature demonstrates impressive ASL sensitivity to a range of neuropathologies and treatment responses. Despite its potential, challenges persist in the translation of ASL to widespread clinical use, including the lack of standardization and the limited availability of comprehensive training. As experience with ASL continues to grow, the final stage of translation will require moving beyond single site observational studies to multi-site experience and measurement of the added contribution of ASL to patient care and outcomes.

Radiomics of Late Gadolinium Enhancement Reveals Prognostic Value of Myocardial Scar Heterogeneity in Hypertrophic Cardiomyopathy.

BACKGROUND: Late gadolinium enhancement (LGE) scar burden by cardiac magnetic resonance is a major risk factor for sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). However, there is currently limited data on the incremental prognostic value of integrating myocardial LGE radiomics (ie, shape and texture features) into SCD risk stratification models. OBJECTIVES: The purpose of this study was to investigate the incremental prognostic value of myocardial LGE radiomics beyond current European Society of Cardiology (ESC) and American College of Cardiology (ACC)/American Heart Association (AHA) models for SCD risk prediction in HCM. METHODS: A total of 1,229 HCM patients (62% men; age 52 ± 16 years) from 3 medical centers were included. Left ventricular myocardial radiomic features were calculated from LGE images. Principal component analysis was used to reduce the radiomic features and calculate 3 principal radiomics (PrinRads). Cox and logistic regression analyses were then used to evaluate the significance of the extracted PrinRads of LGE images, alone or in combination with ESC or ACC/AHA models, to predict SCD risk. The ACC/AHA risk markers include LGE burden using a dichotomized 15% threshold of LV scar. RESULTS: SCD events occurred in 30 (2.4%) patients over a follow-up period of 49 ± 28 months. Risk prediction using PrinRads resulted in higher c-statistics than the ESC (0.69 vs 0.57; P = 0.02) and the ACC/AHA (0.69 vs 0.67; P = 0.75) models. Risk predictions were improved by combining the 3 PrinRads with ESC (0.73 vs 0.57; P < 0.01) or ACC/AHA (0.76 vs 0.67; P < 0.01) risk scores. The net reclassification index was improved by combining the PrinRads with ESC (0.25 [95% CI: 0.08-0.43]; P = 0.005) or ACC/AHA (0.05 [95% CI: -0.07 to 0.16]; P = 0.42) models. One PrinRad was a significant predictor of SCD risk (HR: 0.57 [95% CI: 0.39-0.84]; P = 0.01). LGE heterogeneity was a major component of PrinRads and a significant predictor of SCD risk (HR: 0.07 [95% CI: 0.01-0.75]; P = 0.03). CONCLUSIONS: Myocardial LGE radiomics are strongly associated with SCD risk in HCM and provide incremental risk stratification beyond current ESC or AHA/ACC risk models. Our proof-of-concept study warrants further validation.

Appropriateness of hysterectomies at the time of surgical removal of presumed benign adnexal masses.

OBJECTIVE: To evaluate factors that affect a gynecologist's decision to remove an asymptomatic uterus at the time of removal of a presumed benign adnexal mass. METHODS: Retrospective chart review of hysterectomies conducted when removing presumed benign adnexal masses at a tertiary-care academic center. Primary outcome was the final pathology of the adnexal mass to determine whether the hysterectomy was medically indicated. Secondary outcomes included the rate of postoperative complications. RESULTS: We included 185 out of 1415 charts. Most hysterectomies were performed by gynecologic oncologists (68.8%); 113 (61%) had a frozen section and of those, 76 (67.3%) were benign. Final adnexal pathology was benign in 135 (73%) cases. Using a bivariate analysis, menopausal status (P = 0.019), parity (P = 0.047), sonographic appearance of the mass (P = 0.049), and the physician's preoperative suspicion for malignancy (P < 0.001) were significantly associated with the final adnexal pathology. At the multivariate level, only the physician's suspicion for malignancy was significantly associated with the final adnexal pathology (P < 0.0001) with an odds ratio of 7.28 (95% confidence interval 3.11-17.02). CONCLUSION: Despite gynecologists' capacity to predict the malignant nature of an adnexal mass, 135 of 185 (73%) hysterectomies were performed without a clear medical indication, at the time of removal of benign adnexal masses.