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.

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