Detection and Predictive Value of Fractional Anisotropy Changes of the Corticospinal Tract in the Acute Phase of a Stroke.

BACKGROUND AND PURPOSE: A decrease in fractional anisotropy (FA) of the ipsilesional corticospinal tract (CST) distal to stroke lesions in the subacute (eg, 30 days) and chronic phase has been correlated with poor motor outcomes, but it is unclear whether FA values obtained within the acute stroke phase (here defined as 80 hours after onset) can predict later outcome. METHODS: Fifty-eight patients underwent an assessment of motor impairment in the acute phase and at 3 months using the upper extremity Fugl-Meyer assessment. FA values, obtained within 80 hours after stroke onset, were determined in 2 regions of interest: cerebral peduncle and a stretch of the CST caudal to each stroke lesion (nearest-5-slices). RESULTS: The FA laterality index for the cerebral peduncle-regions of interest was a poor predictor of 3-month outcome (R(2)=0.044; P=0.137), whereas the slope over the FA laterality index of the nearest-5-slices showed a relatively weak but significant prediction (R(2)=0.11; P=0.022) with the affected side having lower FA values. Initial upper extremity Fugl-Meyer (R(2)=0.69; P<0.001) and the weighted CST lesion load (R(2)=0.71; P<0.001) were strong predictors of 3-month outcome. In multivariate analyses, controlling for initial upper extremity Fugl-Meyer, weighted CST lesion load, and days-of-therapy, neither the FA laterality index of the cerebral peduncle nor the slope over the FA laterality index of the nearest-5-slices significantly contributed to the prediction of 86% of the variance in the upper extremity Fugl-Meyer at 3 months. CONCLUSIONS: FA reductions of the CST can be detected near the ischemic lesion in the acute stroke phase, but offer minimal predictive value to motor outcomes at 3 months.

Decision model analyses of upper endoscopy for gastric cancer screening and preneoplasia surveillance: a systematic review.

AIMS: Gastric cancer (GC) is the third leading cause of cancer death worldwide, but the burden of disease is not distributed evenly. GC screening routinely occurs in some high-incidence regions/countries and is generally cost-effective, which is attributed largely to the associated GC mortality reduction. In regions of low-intermediate incidence, less is known about the outcomes of GC screening and gastric precancer surveillance, including cost-effectiveness, since there are no comparative clinical studies. Decision analytic studies are informative in such instances where logistical limitations preclude "gold standard" study designs. We therefore aimed to conduct a systematic review of decision model analyses focused on endoscopic GC screening or precancer surveillance. METHODS: We identified decision model analyses, including cost effectiveness and cost utility studies, of GC screening or preneoplasia surveillance. At minimum, articles were evaluated for: study country; analytic design; population and health states; time horizon; model assumptions; outcomes; threshold value(s) for "cost-effective" determination; and sensitivity analyses. Quality appraisal was performed using a modified Drummond's analytic scoring system. Data sources were PubMed, Web of Science, Embase, and the Cochrane Library. RESULTS: We identified 17 studies (8 screening, 4 surveillance, and 5 screening and surveillance) that met full inclusion criteria. Endoscopic screening in countries of high GC incidence was cost-effective across all studies; targeted screening of high-risk populations within otherwise low-intermediate incidence countries was also generally cost-effective. Surveillance of gastric precancer, including atrophic gastritis or gastric intestinal metaplasia, was generally cost-effective. Most studies had high appraisal scores, with 4 (24%) studies achieving perfect scores on the Drummond scale. CONCLUSION: Decision model analyses offer a unique mechanism with which to efficiently explore the cost benefit of various prevention and early detection strategies. Based on this comprehensive systematic review, upper endoscopy for GC screening and gastric precancer surveillance might be cost-effective depending on the population and protocol. Focused efforts are especially needed not only to define the optimal approach, but also to define the populations within otherwise low-intermediate regions/countries who might benefit most.

Factors associated with nodal metastasis in 2-centimeter or less non-small cell lung cancer.

OBJECTIVE: Lymph node involvement is an important determinant of treatment and prognosis in non-small cell lung cancer (NSCLC) and must be determined via surgical lymph node (LN) evaluation. However, lymphadenectomy is associated with multiple significant morbidities. Recent studies have suggested LN evaluation can be foregone in some or all patients with NSCLC ≤2.0 cm. Our objective was to identify whether these patients may be safely spared the morbidity of lymphadenectomy. METHODS: We undertook a retrospective study of patients treated for NSCLC ≤2.0 cm at a single institution from 2005 to 2017. We examined patient, demographic, and tumor variables for associations with LN metastases via univariable and multivariable analyses. RESULTS: In total, 555 patients met our inclusion criteria. Our primary independent variables included tumor size, histology, and histologic subtype. Although tumors ≤1 cm were less likely to have LN metastases than 1.1- to 2-cm tumors (6.8% vs 13.3%), there was no statistically significant difference. Histologic type was not associated with LN status. In an adenocarcinoma subgroup analysis, micropapillary predominant tumors were more likely to have LN metastases. All invasive mucinous adenocarcinomas and minimally invasive adenocarcinomas were N0. CONCLUSIONS: LN evaluation may be unnecessary in patients with minimally invasive adenocarcinoma or invasive mucinous adenocarcinomas ≤2.0 cm. However, this information is rarely available pre- or intraoperatively. Thus, we recommend LN evaluation always be performed when possible, even for subcentimeter NSCLC, unless the histology is absolutely certain. To our knowledge, this is the largest dataset published to study patients with NSCLC ≤2.0 cm.

Right hemisphere structures predict poststroke speech fluency.

OBJECTIVE: We sought to determine via a cross-sectional study the contribution of (1) the right hemisphere's speech-relevant white matter regions and (2) interhemispheric connectivity to speech fluency in the chronic phase of left hemisphere stroke with aphasia. METHODS: Fractional anisotropy (FA) of white matter regions underlying the right middle temporal gyrus (MTG), precentral gyrus (PreCG), pars opercularis (IFGop) and triangularis (IFGtri) of the inferior frontal gyrus, and the corpus callosum (CC) was correlated with speech fluency measures. A region within the superior parietal lobule (SPL) was examined as a control. FA values of regions that significantly predicted speech measures were compared with FA values from healthy age- and sex-matched controls. RESULTS: FA values for the right MTG, PreCG, and IFGop significantly predicted speech fluency, but FA values of the IFGtri and SPL did not. A multiple regression showed that combining FA of the significant right hemisphere regions with the lesion load of the left arcuate fasciculus-a previously identified biomarker of poststroke speech fluency-provided the best model for predicting speech fluency. FA of CC fibers connecting left and right supplementary motor areas (SMA) was also correlated with speech fluency. FA of the right IFGop and PreCG was significantly higher in patients than controls, while FA of a whole CC region of interest (ROI) and the CC-SMA ROI was significantly lower in patients. CONCLUSIONS: Right hemisphere white matter integrity is related to speech fluency measures in patients with chronic aphasia. This may indicate premorbid anatomical variability beneficial for recovery or be the result of poststroke remodeling.