br Introduction br Case report A year old man

Introduction
Case report A 69-year-old man without a remarkable medical history suffered from an acute left-sided weakness and speech disturbance. He was sent to the emergency department of our hospital. His initial Glasgow Coma Scale (GCS) was E3M6V3, his blood pressure was 156/80mmHg and left-sided hemiparesis (Medical Research Council (MRC) grade 3/5 of both upper and lower limbs) and dysphasia were noted. A computerized tomography (CT) scan with contrast medium disclosed a right frontal lobar ICH with no abnormal surrounding enhancement (Figs. 1A and B). The patient had an associated mass effect and no known cause for the ICH, so a craniotomy for ICH evacuation was performed. No abnormal cerebrovascular or tumor-like lesions were found during the operation, and histopathology showed blood clots only. Following the operation, the patient’s muscle power in his left limbs improved to a MRC grade 4–5/5 and his GCS improved to E4M6Vt. Two days later he became drowsy, with a GCS of E1M4Vt. A CT scan revealed a new cortical and subcortical lobar ICH in the right parietal lobe with significant subfalcine cerebral herniation (Figs. 1C and D). Accordingly, a decompressive craniectomy and hematoma evacuation were performed. Histopathology of the brain tissue overlying the hematoma showed CAA (Fig. 2). His GCS recovered to E4M4V1 and he was transferred to a general ward for further care. Four weeks after the second operation, the patient became lethargic (with a GCS of E2M4V1) and a bulging and tense craniectomy window was seen 6 hours after a cystoscopy for a urinary SCR 7 stone and benign prostatic hypertrophy. A repeat CT scan disclosed a recurrent ICH in the right parietal lobe (Figs. 3A and B). There was sufficient intracranial pressure control through the craniectomy window for a conservative treatment to be adopted. The patient’s GCS recovered gradually to E4M4V1 and remained stationary in the year that followed, until a new ICH occurred in the left frontal lobe following a right femoral neck fracture and episodes of seizure (Figs. 3C and D). Due to the minimal mass effect from the hematoma, conservative treatment was again adopted and the symptoms gradually subsided.
Discussion Amyloid proteins are improperly folded proteins accumulating intra- and extra-cellularly. Several human amyloid proteins have been identified, and there is specific tissue affinity for their deposition. The deposition of amyloid protein within leptomeningeal and cortical arteries, arterioles, capillaries and, rarely, veins is defined as CAA, and the mechanisms of amyloid formation and deposition in cerebral blood vessels are highly complex. Genetic, biochemical and physiochemical effects account for the pathogenesis of CAA. The processes triggering cascades of secondary events include inflammation, oxidative stress and cell toxicity, all of which eventually initiate the development of neurodegeneration, such as stroke and dementia. The prevalence of CAA increases with age and the development of dementia. Postmortem investigations indicate that CAA occurs in up to 92% of patients with Alzheimer’s dementia. In non-demented people, CAA is rarely seen before the age of 50 years, but may occur in one-third of individuals after the age of 60. The prevalence of CAA increases to more than 50% in people over age 90 years. Most patients with CAA manifest with non-specific vasculopathy-related neurodegeneration, such as impaired memory and cognition, psychological conditions, ataxia, extrapyramidal signs, seizures and motor dysfunction. The most serious presentation is CAAH. CAAH is an important cause of morbidity and mortality in elderly patients. A tentative diagnosis of CAAH is often based on clinical presentations: lobar, cortical or cortico-subcortical cerebral hemorrhages; and cerebral hemorrhages affecting normotensive individuals over the age of 55 years that are frequently multiple and recurrent. The definitive diagnosis of CAAH, however, relies on histopathology showing pink hyaline thickening of the arteries and arterioles under hematoxylin-eosin staining, and apple-green birefringence under polarized light on Congo red staining. Brain biopsy is limited by its invasiveness, and is therefore not practical for screening. Non-invasive methods have been developed to detect the possibility of CAA. T2-weighted gradient echo magnetic resonance imaging highlights the presence of hemosiderin in the foci of a microhemorrhage. Positron emission tomographic imaging with the β-amyloid-binding Pittsburgh compound B has been reported as a potentially reliable technique for detecting the presence of β-amyloid, and so identifying CAA in living patients. These non-invasive methods are of limited use, however, in the emergency status of ICH.