CONTRIBUTION OF T2 * WEIGHTED SEQUENCE IN THE PATHOLOGY OF CEREBRAL SMALL VESSEL IN THE ELDERLY
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CONTRIBUTION OF T2 * WEIGHTED SEQUENCE IN THE PATHOLOGY OF
CEREBRAL SMALL VESSEL IN THE ELDERLYS.BELABBES, S.BELASRI, S.CHAOUIR, T.AMIL, A.HANINE, D.BASSOU
Department of Radiology, Military Teaching Hospital Mohammed V of Rabat. Morocco
NR24
INTRORUCTION
Intracerebral hemorrhage in the elderly: Is an important cause of mortality and
neurological morbidity. May be due to two main artériolopathies:
1 – Arterial hypertension (AHT): Fisher Lipohyalinosis
2 – sporadic cerebral amyloid angiopathy.
Materials and Methods
Iconographic illustration of retrospective head MRI performed in patients treated for an acute or chronic, ischemic or haemorragic pathology, or an array of cognitive decline.
MRI with gradient echo sequence T2 *
RESULTS
In T2 *: the appearance and distributionl of low signal intensity of brain parenchyma have allowed us to distinguish: Punctate hemorrhage (PH) predominant in
diencephalic region, brainstem and the cerebellar hemispheres: lipohyalinosis (AHT).
Punctate hemorrhage in the cortico-subcortical junction.: Amyloid angiopathy
DISCUSSION
the chronic pathology of cerebral small vessel causes a chronic ischemia in the territories concerned, source of brain dysfunction whose later expression is dementia
It includes several entities dominated by: The arteriopathy of chronic arterial
hypertension :patients under 55 years. Risk of recurrent bleeding: 2%.
The amyloid angiopathy (AA): Concerns elderly over 60 years. Risk of recurrence exceeds 10%
DISCUSSION
Chronic hypertension and amyloid angiopathy degrades and weakens cerebral artery walls small caliber by deposition of amyloid
causes them to break directly, or after formation of microaneurysms of Charcot-Bouchard
DISCUSSION
• deep topography: On the perforating arteries the diencephalon the Basal ganglia The posterior fossa The pons The cerebellum
• more or less associated with a peripheral location at the junction of gray matter-white matter.
Chronic Arterial Hypertension
MRI: T2 * sequence, axial section.Low signal intensity, predominantly in the diencephalic region (A), and in the cerebellar hemispheres (B).
A B
DISCUSSION
age over 60 years•lobar topography sus tentorial, predominant in frontal regions• seat cortico-subcortical• respect for deep structures, white matter, cerebellum• frequent coexistence with arterial hypertension lesions.
Amyloid Angiopathy
Amyloid Angiopathy
T2 * MRI, axial section:Presence of low signal intensity in the cortico-subcortical junction.
DISCUSSION
T2-gradient echo or T2 *, sensitive to magnetic susceptibility artifact.
Detects hemorrhages in the acute stage (deoxyhemoglobin) and chronic stage (hemosiderin), not detectable on conventional sequences or macroscopic examination.
T2*+++
CONCLUSION
T2 * weighted imaging1-is essential for exploration of:
Encephalic vascular damage, acute or chronic.
Cognitive impairment.2-It allows positive diagnosis of cerebral microhemorrhages3-And according to the topographic distribution of microhemorrhages, can approach the etiologic diagnosis.
BIBLIOGRAPHY1-Lahutte M, Darbi A, Lévêque C, Cordoliani YS. Pathologie chronique des petits vaisseaux cérébraux et malformations vasculaires occultes: apport de la séquence de susceptibilité magnétique T2*. Feuillets de radiol,2006:46:3:182-1902- Gere J, Minier D, Osseby GV, Couvreur G,Moreau T, Ricolfi F, et al. Epidémiologie des accidents hémorragiques cérébraux. J Neuroradiol 2003; 30: 291-7.3- Lee SH, Kwon SJ, Kim KS, Yoon BW, Roh JK. Topographical distribution of pontocerebellar microbleeds. AJNR Am J Neuroradiol 2004; 25: 1337-41.4- Roob G, Lechner A, Schmidt R, Flooh E, Hartung HP, Fazekas F. Frequency and location of microbleeds in patients with primary intracerebral hemorrhage. Stroke 2000; 31: 2665-9.