A forum dedicated to the expansion in neuropathology knowledge for students and practitioners alike.
Cranial nerve schwannomas most commonly arise from Schwann cells that myelinate the distal aspect of the vestibular division of the 8th cranial nerve. Vestibular schwannomas, sometimes referred to by the double misnomer "acoustic neuroma" (it is a double misnomer because they are not neuromas and they do not usually involve the acoustic division of cranial... Continue Reading →
For many years the only mechanism for observing gross pathologic features of CNS neoplasms was to examine brains extracted after death. However, advancements in imaging technology now allow providers to observe typical gross neuropathological findings in the brains of living patients. Some brain tumors have characteristic MRI findings, an example of which is a cyst... Continue Reading →
Schwannomas are peripheral nerve sheath tumors that arise from cells that myelinate peripheral nerve axons called Schwann cells. A classic histologic finding in schwannomas are Verocay bodies (arrows), which consist of short palisades of tumor cell nuclei separated by eosinophilic anucleate bands of tumor cell processes. Verocay bodies are often more prominent in schwannomas that arise in the setting of a... Continue Reading →
Oligodendrogliomas often show the classic “fried egg” appearance, in which each cell contains a small round monomorphic nucleus with a perinuclear region of clearing, as well as small delicate blood vessels, or “chicken-wire vasculature”. The fried egg morphology is an artifact of formalin fixation and will not be observed in frozen tissue sections. In addition,... Continue Reading →
Astrocytomas (i.e. glial tumors that diffusely infiltrate through brain tissue) are composed of neoplastic astrocytes that may occasionally exhibit certain morphologic differences when observed microscopically. Gemistocytic astrocytes are characterized by eccentric nuclei and plump pink cytoplasm that superficially resembles the belly of a pregnant woman when viewed from above. Neoplasms that are predominantly composed of... Continue Reading →
Cerebral edema, or increased swelling in the brain, can occur as the result of numerous etiologies, such as infection, inflammation, metabolic derangement, or neoplastic processes. Typically the brain has an undulating contour featuring crests or bumps called gyri, and troughs or grooves, called sulci. The mass effect produced by cerebral edema results in pushing or... Continue Reading →
Dandy-Walker malformation, an uncommon brain abnormality that may be seen in isolation or in association with other congenital abnormalities of brain development, is characterized by an enlarged posterior fossa, agenesis or hypoplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle. In this case of a term infant with multiple congenital abnormalities, the superior most aspect of the... Continue Reading →
A lacunar infarct is a small infarction, or stroke, that is usually less than about 1 to 1.5 cm in size and typically occurs in deep cerebral structures (e.g. basal ganglia) of hypertensive or diabetic patients with small vessel disease of deep penetrating arteries (e.g. lenticulostriate arteries) . The gross impression of this brain, which belonged to... Continue Reading →
Naegleria fowleri, better known as "brain-eating amoeba", is a free-living amoeba that is a major cause of a rare brain infection called Primary Amebic Meningoencephalitis, which typically affects young people with a history of swimming in warm fresh water such as a lake or stream. After entering the nose and crawling up the olfactory nerves... Continue Reading →
