Keywords:
Vascular, Ultrasound-Colour Doppler, Ultrasound, MR, Comparative studies, Arteriosclerosis, Geriatrics
Authors:
A. Hayirlioglu1, N. Özgür2, M. G. Yilmabasar1; 1Istanbul/TR, 2İstanbul /TR
DOI:
10.1594/ecr2013/C-2091
Methods and Materials
Leukoaraiosis is characterized by white matter hyperintense lesions (WMHRL) on T2-weighted magnetic resonance imaging (MRI) as the frequent finding of brain aging (1).
WMHRL indicate a strong relationship between age,
arterial hypertension,
diabetes and other vascular risk factors(2.3).
However,
the genetic predisposition is thought to be closely related in terms of leukoaraiosis.
Histological underlying causes are decreased myelin,
axonal loss and astrocytic gliyozis (4.5).
Population-based epidemiological studies,
suggests the link between cognitive performance,
psychomotor deceleration and balance disorder of elderly people who have WMHRL.
Healthy people of advanced age,
put forward a clear association between decreased mental performance and WMHRL (6).
The presence of WMHRL may be a risk factor for stroke(7,8).
Pathogenesis of WMHRL is not fully cleared.
Small vessel disease appear to be the main etiological factor of WMHRL(9),
also disruption of the blood brain barrier may have effect on the process (10).
However,
close association between the presence of atherosclerosis in the large arteries,
the deep white matter infarcts and leukoaraiosis are well establised (8,11 to 15).
Any large arterial disease wich cause white matter ischemia could be an indirect factor in the development of leukoaraiosis.
Arterial tromboembolization leading to irreversible hemodynamic changes may play a secondary role in this mechanism.
In our study,
in patients with patchy hyperintensities which tended to coalesce,
compatible with leukoaraiosis on MRI,
intima-media thickness,
types of atherosclerotic plaque and stenosis of the internal carotid arteries were measured.
We aim to analyse prospectively the relationship between the Leukoarios and extracerebral arterial system,
using a control group; to investigate the pathophysiology and risk factors of leukoaraiosis.
In this study between 2010-2011,
32 patients (Group A) who applied to Medeniyet University Goztepe Training and Research Hospital Radiology Department,
between the ages of 55-90 patchy hyperintensities that tend to coalesce on T2-weighted MR sequences compatible with periventricular leukoaraiosis,
(figure 14) were examined by color Doppler of the carotid arteries.
Toshiba Medical Systems Corp.
device Aplio 7.5 MHz linear probe was used.
The control group (Group B) consist of 36 patients was in same age range as the Group A.
Examinations were performed in supine position,
as head was slightly extended position.
On gray scale examination bilateral carotid arteries were displayed.
Intima-media thickness was measured.
The ostium of ICA and ECA displayed.
Characteristics of the existing plaques were classified on cervical ICA segment.
With pulse wave,
color wave and spectral doppler presence of stenosis were investigated in carotid arteries.
Up to 50% Stenosis degrees are classified using NASCET and ACAS criteria as a method of directly visual grading system.
More than 50% stenotic lesions were assessed by peak systolic velocity.
Existing plaques in carotid arteries were characterized by ultrasonography (Bock-Lusby Classification).
Type 1 plaque is characterised by hypoechoic plaques,
Type 2 plaques are more hypoechoic component,
but also containing echogenic component,
Type 3 plaques have predominant echogenic component of the more calcified ones are characterized as Type 4.
Degree of stenosis in the carotid artery were identified in 4 categories: Group 1 patients had no stenosis,
group 2,
3 and 4,
carotid arteries have % 0 - 29%,
30-60% and 60 - 99% stenosis respectively.
Occlusions were not included in the study.
As a complementary factor,
atherosclerotic irregularities,
and the mean intima-media thickness on carotid artery were graded.
No apparent irregularity in the atherosclerotic intima-media wall characterized as (-),
0.8mm-1mm wall thickness and atherosclerotic irregularity cases graded as (+),
and atherosclerotic irregularity with a thickness more than 1mm were categorized as (+ +).
Plaques detected in the carotid arteries classified into 4 categories according to their gray-scale ultrasound examination based on Bock- Lusby Classification.
Statistical data were analyzed by Mann-Whitney U test,
Fisher's exact chi-square test,
Pearson's test.