医生怀疑他的记忆问题是由慢性脑病引起的。

The doctor suspected his memory issues were caused by chronic ___encephalopathy.

医生诊断他患有肝性脑病，这是一种由肝功能衰竭引起的脑功能障碍。

The doctor diagnosed him with hepatic ___encephalopathy, a brain dysfunction caused by liver failure.