instruction:
Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
question:
Pulmonary hypertension (PH) is associated with a poor prognosis in diffuse lung disease (DLD). A study was undertaken to compare the prognostic significance of invasive and non-invasive parameters in patients with DLD and suspected PH.', 'Hospital records of consecutive patients with DLD undergoing right heart catheterisation (RHC) were reviewed (n = 66). Mean pulmonary artery pressure (mPAP), pulmonary vascular resistance (PVR) and non-invasive variables were examined against early (within 12 months) and overall mortality. A priori thresholds were examined against early mortality. Relationships between mPAP, PVR and non-invasive markers were assessed.', 'Fifty patients had PH on RHC (mean (SD) mPAP 33.5 (11.8) mm Hg, PVR 5.9 (4.3) Wood units (WU)). Raised PVR was strongly associated with early mortality (odds ratio (OR) 1.30; 95% confidence interval (CI) 1.11 to 1.52; p = 0.001), with PVR > or = 6.23 WU being the optimal threshold after adjustment for age, gender, composite physiological index (CPI) and diagnosis of idiopathic pulmonary fibrosis (OR 11.09; 95% CI 2.54 to 48.36; p = 0.001). Early mortality was linked, albeit less strongly, to right ventricular dilation at echocardiography, but not to other non-invasive variables or mPAP. Overall mortality was most strongly associated with increasing CPI levels. Correlations between PVR and non-invasive variables were moderate (R(2) <0.32), improving little following construction of a multivariate index which did not itself predict mortality.
answer:
Does pulmonary vascular resistance predict early mortality in patients with diffuse fibrotic lung disease and suspected pulmonary hypertension?


question:
Hostile neck anatomy is assumed to be associated with increased surgical risk for patients undergoing carotid endarterectomy (CEA) and is often considered a reason to choose carotid stenting or medical management. This retrospective case-control study evaluated whether, and how much, anatomically hostile necks represent a condition of higher surgical risk of early and late mortality and major or minor morbidity.', 'The data for 966 homogeneous CEA patients was prospectively entered in a computer database. Seventy-seven had a hostile neck anatomy due to previous oncologic surgery or neck irradiation, restenoses after CEA, high carotid bifurcation, or bull-like and inextensible neck. A case-control matched-pair cohort study considered sex, age (5-year intervals), and year of operation. Regional anesthesia was used for all operations for atherosclerotic stenosis >or=70%, conforming to the European Carotid Surgery Trial (ECST) in symptomatic and asymptomatic patients, at a single center and by one surgeon or under his direct supervision.', 'The hostile neck patients and the control group were matched for age, sex, carotid-related symptoms, degree of stenoses, and main risk factors for cardiovascular diseases. Intraoperative variables were substantially equivalent in the two groups; however, procedure length and clamping time were, respectively, about 22 minutes (P = .0001) and 7 minutes longer (P = .01) in the hostile neck group. Rates of postoperative mortality and neurologic events were equivalent. Peripheral nerve lesions were multiple and significantly more frequent in the hostile neck patients (21% with >or=1 cranial nerve lesion vs 7% of controls, P = .03), yet all were transient and limited to a few months. The subgroups of patients with hostile neck, restenoses, and bull-like inextensible necks required the longest operative and clamping time, and those with bull-like and high bifurcation had the most frequent cranial nerve dysfunctions. At the respective follow-up of 47 and 45 months, survival curves (P = .48) and the incidence of restenoses and fatal and nonfatal strokes were similar (5 and 4, respectively).
answer:
Does the hostile neck increase the risk of carotid endarterectomy?


question:
Thrombotic thrombocytopenic purpura (TTP) is a rare hematologic disorder that frequently presents with neurologic involvement. However, the yield and prognostic value of acute brain neuroimaging in patients with TTP has not been studied. Our aim was to evaluate brain imaging findings in consecutive patients with TTP and assess their impact on prognosis.', 'We retrospectively collected clinical, laboratory, and neuroradiologic information in 47 episodes of acute TTP studied with brain imaging at our medical center between 1997 and 2007. Head CT and brain MRI were evaluated independently by 2 investigators. We then performed statistical analysis to determine whether the presence of acute lesions on brain imaging was associated with worse functional outcome as assessed by the modified Rankin score upon discharge and long-term follow-up.', 'Ten patients (25%) of those who had a head CT had acute changes, half of them indicating posterior reversible encephalopathy syndrome (PRES). Most cases studied with brain MRI had acute changes (82%). More than half of those had evidence of PRES (48%). Atypical variants of PRES were seen in 2 patients with isolated basal ganglia involvement. Acute ischemia and hemorrhage were uncommon. Most patients with acute changes on brain imaging recovered favorably, and radiologic lesions were not associated with worse functional outcome.
answer:

Are brain lesions most often reversible in acute thrombotic thrombocytopenic purpura?