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Peiyi Gao

Publications and source records attributed to Peiyi Gao.

3 recordsLinked to original sources

Correlation of MR imaging and histopathology after partial resection of normal rabbit brain.

OBJECTIVES: To investigate the findings of magnetic resonance (MR) imaging and histopathology in early postoperative normal brain, and to define the correlation between MR images and histopathology. METHODS: Thirty-six New Zealand rabbits weighing 2.0 to 3.0 kg were divided into 10 groups according to different postoperative days: 1 to 10 days. A partial resection of the parietooccipital region was performed under usual aseptic conditions after the animals were anesthetized intravenously with 3% pentobarbital (30 mg/kg). MR imaging procedures consisted of pre- and postcontrast scanning and were carried out on postoperative days 1 to 10. Brain tissue samples were prepared for examination immediately after MR scanning. Histopathological examination was done under light both and electron microscopes. The findings of MR imaging were compared with histopathologic findings. RESULTS: Surgical margin contrast enhancement on MR images could be seen 24 hours after surgery. The degree of contrast enhancement increased gradually up to 5 days postoperation, and no remarkable changes were present from days 5 to 10. Disruption of the blood brain barrier (BBB) was the main cause of contrast enhancement during the first 3 postoperative days. After that period, the mechanism responsible for contrast enhancement was the formation of neovascularity and a broken BBB. An increase in the amount of neovascularity played a predominant role in contrast enhancement in normal postoperative brain tissue. CONCLUSIONS: The features of enhanced MR images present at the surgical margin followed a typical time course during the early postoperative period. The role of neovascularity and BBB disruption in the formation of contrast enhancement at the surgical margin varies with time. Knowledge of the features of contrast enhancement in postoperative MR images of normal brain can help in differentiating benign changes from residual malignant glioma.

Animals↗

[A study on the diagnosis and etiology of cerebral venous thrombosis].

OBJECTIVE: To determine the clinical characteristic and common etiologies of cerebral venous thrombosis (CVT) in China. METHODS: Clinical and neuroimaging data of 91 cases of CVT were analyzed retrospectively. RESULTS: 91 CVT patients (49 men, 42 women), aged from 9 to 57 years, were diagnosed with MRI (78 cases, 85.71%), MRA (37 cases, 40.66%) or DSA (32 cases, 35.16%). 27 cases (29.67%) had a clinical pattern of isolated intracranial hypertension, 56 cases (61.54%) of focal deficits and/or seizures, 3 cases of subacute encephalopathy and 5 cases of cavernous sinus thrombosis. Oral contraceptive was the most common cause, being found in 12 cases (13.19%). CONCLUSIONS: Understanding of the clinical characteristics of CVT and using of MRI and MRA examination as early as possible is the key in CVT diagnosis. Oral contraceptive is the most common etiology.

Adolescent↗