title: Morphological MRI characteristics of recent small subcortical infarcts.
abstract: BACKGROUND
  New imaging criteria for recent small subcortical infarcts have recently been proposed, replacing the earlier term 'lacunar infarction', but their applicability and impact on lesion selection is yet unknown.
  
  
  OBJECTIVE
  To collect information on the morphologic characteristics and variability of recent small subcortical infarcts on magnetic resonance imaging in regard to lesion location and demographic variables.
  
  
  METHODS
  We identified all patients with acute stroke and cerebral magnetic resonance imaging from 2008 to 2013 in our hospital database and selected those with a single recent small subcortical infarct defined by an estimated maximal axial diameter of 20 mm. Recent small subcortical infarcts were segmented on diffusion-weighted imaging and fluid-attenuated inversion recovery sequence to calculate the largest axial and longitudinal diameter and lesion volume. We assessed morphometric differences of recent small subcortical infarcts regarding location and demographic variables and the impact of different recent small subcortical infarct definitions on lesion selection.
  
  
  RESULTS
  Three hundred forty-four patients (median age 72; range 25-92 years, 65% male) were selected. Most recent small subcortical infarcts were located in the basal ganglia (n = 111), followed by pons (n = 92), thalamus (n = 77), and centrum semiovale (n = 64). Quantitative measurements confirmed visual assessment of the axial diameter in 95%. All morphometric variables were strongly intercorrelated and comparable on diffusion-weighted imaging and fluid-attenuated inversion recovery sequence. Recent small subcortical infarcts in the basal ganglia were significantly larger both in the axial and longitudinal direction compared with other regions. Dichotomization of recent small subcortical infarcts according to axial (≤ / >15 mm) or longitudinal (≤ / >20 mm) sizes resulted in different regional frequencies and distributions. Age, gender, and time from stroke onset to magnetic resonance imaging did not influence lesion metrics or the distribution of recent small subcortical infarcts.
  
  
  CONCLUSIONS
  Our study confirms the recent neuroimaging criteria for recent small subcortical infarcts as a practical concept. Definitions of the maximal axial and longitudinal diameter have a significant impact on the frequency and distribution of selected infarcts, which has to be considered for future studies.
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Thomas
authors: T
authors: Gattringer
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Sebastian
authors: S
authors: Eppinger
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Daniela
authors: D
authors: Pinter
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Lukas
authors: L
authors: Pirpamer
authors: Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz, Austria.
authors: Andrea
authors: A
authors: Berghold
authors: Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz, Austria.
authors: Gerit
authors: G
authors: Wünsch
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Stefan
authors: S
authors: Ropele
authors: Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.
authors: Joanna M
authors: JM
authors: Wardlaw
authors: Department of Neurology, Medical University of Graz, Graz, Austria.|Department of Radiology, Division of Neuroradiology, Medical University of Graz, Graz, Austria.
authors: Christian
authors: C
authors: Enzinger
authors: Department of Neurology, Medical University of Graz, Graz, Austria.
authors: Franz
authors: F
authors: Fazekas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001921:Brain / Q000473:pathology*; D002544:Cerebral Infarction / Q000209:etiology / Q000473:pathology*; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007297:Inpatients; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020521:Stroke / Q000150:complications
keywords: MRI; lacunar infarcts; morphology; recent small subcortical infarcts