I discuss issues pertaining to the practice of neuropathology -- including nervous system tumors, neuroanatomy, neurodegenerative disease, muscle and nerve disorders, ophthalmologic pathology, neuro trivia, neuropathology gossip, job listings and anything else that might be of interest to a blue-collar neuropathologist.
Thursday, May 28, 2009
High-Dose Bapineuzumab Puts Some Alzheimer Patients At Risk for Vasogenic Cerebral Edema
Source: Neurology Today (May 21, 2009), page 4.
Monday, May 25, 2009
A 75-year-old man with a large, subretinal mass requiring enucleation
The following is a whole mount of the globe with optic nerve on left and iris on right:
This is a photomicrograph of the anterior chamber angle, which is involved by tumor:
Here is a sampling of different regions within the tumor:
This is a uveal malignant melanoma, mixed cell type. Although the retina harbors a pigmented epithelium, melanomas do not arise from the retina but rather from the melanocytes inhabiting the uveal tract. The uvea is a continuous entity comprised of the iris, ciliary body, and choroid. Melanomas can arise anywhere along the uveal tract. In this case, the melanoma is arising in the choroid and extends into the ciliary body. Tumoral involvement of the irido-corneal angle led to blockage of aqueous humor reabsorption in this patient, resulting in increased intraocular pressure (glaucoma). Three cell types are seen in uveal melanomas: spindle A, spindle B, and epithelioid. Spindle A cells have markedly elongated nuclei and uncommonly have mitotic figures. Spindle B cells share with A-type cells an elongated profile, but spindle B cells have larger, more ovoid nuclei harboring a more prominent nucleolus. Epithelioid melanoma cells are rounder and more anaplastic in appearance, tend to be discohesive, and are occasionally multinucleated. The current case contains a mixture of spindle B and epithelioid type cells. The presence of epithelioid cells confers a worse prognosis. Tumor size is another prognostically significant feature. In contrast to cutaneous melanomas, however, the lateral extent of the tumor is a more significant prognostic feature than is depth. Other prognostically adverse histopathologic features include: high mitotic count; ciliary or choroidal location (iris melanomas fare better); optic nerve extension; intrascleral extension; necrosis; lymphocytic infiltration; neovascularization; and nucleolar prominence. Since there are no lymphatics within the eye, metastasis of uveal neoplasms take an exclusively hematogenous route, with seeding to the liver outnumbering other sites by a very wide margin. Although enucleation is the treatment of choice for larger choroidal melanomas (basal diameter >15 mm and height >10 mm), new precision radiotherapies such as proton beam irradiation and plaque brachytherapy can provide eye-sparing treatments for smaller lesions. As a result, pathologists today see far fewer enucleation specimens secondary to melanoma than in the past. Nevertheless, approximately 10-15% of eyes treated with precision radiotherapy ultimately require enucleation due to subsequent local recurrence or procedure-related glaucoma.
1. Folberg R. “Chapter 29: The Eye” in Robbins and Cotran Pathologic Basis of Disease, 7th ed. (Kumar, Abbas, Fausto, editors) Elsevier, 2005;1434.
2. Stallard HB. “Chapter 43: Diseases of the Choroid” in The Eye and Its Diseases, 2nd ed. (Berens C, editor). WB Saunders: 1949;560-563.
3. Rosai J. “Chapter 30: Eye and Ocular Adnexa” in Rosai and Ackerman’s Surgical Pathology, 9th ed. Elsevier: 2004;2751-2757.
Dr. Diamandis develops network to help pathologists interface with AI computational scientists
A neuropathology colleague in Toronto (Dr. Phedias Diamandis) is developing some amazing AI-based tools for pathology and academia. He hel...
Remarkable en bloc dissection of human central and peripheral nervous system accomplished at University of ColoradoShannon Curran, MS with her dissection Shannon Curran, a graduate student in the Modern Human Anatomy Program at the University of Co...
The meticulously extracted nervous system of a 19th-century woman on display at Hahnemann Medical CollegeLast summer I put up a post about a remarkable whole nervous system dissection that was carried out at the University of Colorado School of ...