Transcript Moss: Golden Grapes

Radiology and Pathology
Teaching Points
Sessions III and IV
Pat Hudgins and Dan Brat
III.1: Sacramentum Gladiatorium
III – Case 1
Processes in sphenoid sinus can
affect the orbit/visual pathways
III – Case 1
Meningeal enhancement around
inflammatory processes is common
Mucocele with superimposed bacterial
infection
Always send cultures if disease could be
infectious. Stains would not have revealed
the type of organism or therapeutic
resistance.
III.2: Diabetes Does Not Explain it All
III – Case 2
Volume loss is hard to quantify
• Corpus callosal
thinning
• Vermian atrophy
• Medullary atrophy
III – Case 2
WM changes in unusual places
• Temporal horns and sweeps
III – Case 2
WM changes symmetric
• Int/ext capsule, both frontal and occipital
Polyglucosan bodies accumulate in the central and
peripheral nervous systems and are often associated
with glycogen branching enzyme (GBE) deficiency
A. Teased-fiber from sural nerve
with axonal enlargements due to
polyglucosan bodies.
B. Semithin section shows axonal
accumulations of glycogen deposits.
(PAS)-positive polyglycosan
bodies within the neuropil of the
basal pontine gray matter (arrow).
III.3: Double Vision? … Give Your Head a Shake
III – Case 3
Initial MRI
• Volume loss is common, hard to quantify
III – Case 3
Initial MRI
7 months later
Testicular germ cell tumors occasionally regress
spontaneously (estimated at 4%) and may manifest
later by autoimmune or metastatic disease.
Anti-CRMP5 paraneoplastic disease more often includes
cerebellar ataxia, chorea, and ocular manifestations
Pathology of active paraneoplastic cerebellar encephalitis
consists of a T-cell infiltrate, generally directed at
Purkinje cells.
III.4: Clues Hidden in the Skin
III – Case 4
Infinite gray scale options mean images
can be displayed in weird ways
Chediak-Higashi syndrome is caused by mutations in
the LYST gene.
Enlarged, dysfunctional lysosomes in neutrophils
prevent appropriate immune responses
Amyloid deposits (SAA type) reflect widespread acute
inflammation
III.5: Spots, spots everywhere, and not a spot to see
III – Case 5
FLAIR
T2
FFE
III – Case 5
FLAIR Sag
III – Case 5
Volumetric images
Obtained in one plane, others are
reformats
RMSF is caused by Rickettsia rickettsii, a species of
bacterium that is spread to humans by Dermacentor
ticks
Serology for IgG is most common laboratory test;
Immunohistochemistry and PCR are also possible.
Session III: What have we learned?
• Put sphenoid sinus/central skull base on
your checklist
• Volume loss is like pornography: you
know it when you see it, but no good
definition
• A good Radiology Dept standardizes gray
scale display
Session III: What have we learned?
• Paraneoplastic disease can be the first
manifestation of neoplastic disease and is due to
antibody-mediated immune response to neuronal
antigens.
• Genetic diagnosis of rare diseases (polyglucosan
body disease; Chediak-Higashi) is becoming more
frequent; the pathology remains important to
understand.
• Serology for IgG is most common laboratory test for
RMSF
IV.1: Raise Your Grade Point Average
IV – Case 1
T1 is so good, why put on fat sat?
Granulomatosis with Polyangiitis (GPA) (Wegener’s
granulomatosis) is a NECROTIZING ANGIITIS
with……
……Granulomatous Inflammation (to distinguish from
Microscopic polyangiitis)
The active vasculitic disease can be difficult to find, but
the necrosis and granulomatous inflammation are
abundant.
IV– Case 2
Microadenoma is usually focal and
discrete
IV– Case 2
More than an adenoma can occur
in the pituitary gland
Pathologist’s favorite saying: “when there is an issue,
get some tissue!!”
Tissue-based diagnosis in this case would not have
been definitive, most likely….
….but it would have ruled out adenoma before radiation.
Not all sellar lesions associated with increased prolactin
levels are adenomas.
Adenoma
Wegener’s Granulomatosis
IV.3: Admissions Ad Nauseum:
A Cryptic Case of Chiasmopathy
IV – Case 3
Whenever there are multiple
opinions re:
Hydrocephalus or
Leptomeningeal enhancement:
The next steps should be…
1)Lumbar puncture
2)Ophthalmoscopic exam
Cryptococcal organisms (budding ovoid yeast forms) have
a thick mucoid capsule that can be seen with
mucicarmine. Also seen on silver stains.
The degree of inflammation may be low in
immunocompromised patients.
Immune reconstitution (IRIS) associated with cryptococcus
in AIDS patients can lead to abrupt and severe
symptoms.
IV.4: A case of Mistaken Identity
IV – Case 4
Yes, it had long T1 and T2, but…
IV – Case 4
there were some hints…..
↑ Vascularity
Necrosis
High grade gliomas in children are fatal diseases, like
adults, but have distinctive sites, molecular profiles
and mutations.
The presence of necrosis would qualify this case as a
glioblastoma, WHO grade IV.
The most frequent congenital brain tumors are
teratomas, astrocytomas, PNETs and choroid plexus
papillomas.
IV.5: OMG, I can't C.
IV – Case 5
DDx for dural enhancement is long
1) Normal dura
• Post-op
2) Edematous dura
• Post-LP
3) Invaded dura
•
•
•
•
•
Granulomatous disease
Infection
Meningioma
Hemangiopericytoma
Mets
Mass-forming lesions due to lymphoplasmacytic
infiltrates and sclerosis, a raised serum IgG4 level
and increased IgG4+ plasma cells in the involved
tissues.
The understanding of IgG4-Related Sclerosing
Disease is still evolving.
Would have been called “inflammatory pseudotumor”
“hypertrophic pachymeningitis” prior to IgG4-RD
IgG
IgG4
Session IV: What have we learned?
• Don’t put fat sat on T1, you lose the
advantages
• More than adenomas happen in the
pituitary
• If you’re going to call a JPA, it shouldn’t be
a vascular or necrotic mass
• Especially if a child is not NF-1, be very
careful about calling a hypothalamic JPA
• Diff Dx for sick dura is really long
Session IV: What have we learned?
• Granulomatosis with Polyangiitis (Wegener’s
granulomatosis) is an aggressive necrotizing
angiitis; difficult to diagnose based strictly on
histologic findings.
• “When in doubt, dig it out”
• IgG4-Related Sclerosing Disease is a newly
described form of inflammatory pseudotumor with
elevated serum IgG4 level and IgG4+ plasma cells
in tissues….still evolving
• Midline enhancing masses in childhood can be due
to low or high grade astrocytomas; the presence of
necrosis suggests a glioblastoma, WHO grade IV
Thank You !