Radiological Imaging of the Visual Pathways
Transcript of Radiological Imaging of the Visual Pathways
Radiological Imaging of the Visual Pathways: A Patient with a Planum Sphenoidale Meningioma
Michael Tibbetts, Harvard Medical School Year IVGillian Lieberman, MD
Michael Tibbetts, 2008Gillian Lieberman, MD
September, 2008
Descartes, 1604•Lavidor M, Walsh V. The nature of foveal representation. Nature Reviews Neuroscience 2004; 5, 729-735.
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Agenda
1. Case Presentation of Patient RR2. Anatomy of the Visual Pathways3. Menu of Tests for Imaging of the Visual
Pathways4. Review of Patient RR’s Imaging Studies5. Discussion of Findings
Michael Tibbetts, 2008Gillian Lieberman, MD
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Patient RR: PresentationHistory:
75 year-old woman who noticed progressive decreased vision in her left eye starting ~2 years ago with no visual changes in right eye– PMH: Hypertension– Ocular history: unremarkable
Exam: 20/25 OD 20/400+1 OS no improvement w/pinholeColor vision 16.5/17 OD, unable to see plates OSRelative afferent pupillary defect OSNo other focal neurological deficits
Michael Tibbetts, 2008Gillian Lieberman, MD
Next step: Direct visualization of the retina and optic nerve head
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Fundus ExaminationMichael Tibbetts, 2008Gillian Lieberman, MD
www.revophth.com/publish/images/1_13156_0.jpg
Clinical Features of Optic Nerve Disease:
1. Afferent pupillary defect2. Optic disc changes3. Poor color vision ?
Patient RR has 2 features suggestive of optic nerve disease (color vision unable to be assessed to do poor vision and field loss not formally evaluated)
http://faculty.washington.edu/alexbert/MEDEX/Fall/eye-fundus.jpg
Optic disc pallor
4. Field loss ?
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Anatomy of the Visual Pathways
Michael Tibbetts, 2008Gillian Lieberman, MD
http://www.iupucanatomy.com/images/Picture%201465.jpg
•Visual information processed by rods and cones of retina
•Transmitted via optic nerves (CNII)
•Nasal fibers cross at the optic chiasm
•Fibers synapse at the lateral geniculate nucleus
•Geniculocalcarine tract forms the optic radiation that fans into optic radiations to occipital cortex
Lesions here cause:Unilateralfield defects
Lesions here cause:Bilateralfield defects*
*Exception: temporal 60-90 degrees of vision (temporal crescent) has monocular representation in the most anterior part of the striate cortex.
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Differential Diagnosis of Unilateral Optic Neuropathy
Inflammation/Infection• Idiopathic demyelinating
optic neuritis
Vascular (infarction)• Anterior ischemic optic
neuropathy• Posterior ischemic optic
neuropathy
Michael Tibbetts, 2008Gillian Lieberman, MD
Trauma •Isolated optic nerve trauma is possible, but very unlikely
Tumor•Optic nerve compression
- Intracranial meningiomas, primary optic nerve sheath tumors
Optic nerve infiltration - Leukemia, lymphoma or disseminated
carcinoma•Chiasmal compression
- Pituitary tumors, craniopharyngioma
Next: Review the Menu of Tests for Imaging the Visual Pathways
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Menu of Tests for Imaging of the Visual Pathways
Michael Tibbetts, 2008Gillian Lieberman, MD
CT+better for osseous detail of
orbits and calcifications+better for assessing orbital
fractures
MRI+better for imaging optic
nerve and tumors+better for evaluation of
cerebral perfusion and post-chiasmal lesions
http://www.djo.harvard.edu/files/2918_349.jpg T1 PACS, BIDM C, 2007
Globe
Maxillarysinus
Inferior Turbinates
Orbital Floor
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Michael Tibbetts, 2008Gillian Lieberman, MD
Ultrasound+used for imaging globe when
no view to posterior pole +used for imaging of foreign
bodies in the orbit-poor penetration and resolution
Angiography+used to assess for vascular
malformations, stenosis or vascularized tumors
-invasive
www.ophthalmicultrasonography.com/CD%20BScan.htm www.urmc.rochester.edu/smd/Rad/diagneuro.htm
Menu of Tests for Imaging of the Visual Pathways
Detached Retina
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MRI Imaging of the Visual PathwaysMichael Tibbetts, 2008Gillian Lieberman, MD
T2 with Fat Saturation – improved visualization of optic nerves
1. Optic canal2. Globe3. Dorsum sellae4. Sphenoid sinus5. Macula6. Medial rectus muscle7. Lateral rectus muscle8. Optic nerve9. Ophthalmic artery10. Temporal lobe
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OpticNerve
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•Wichmann W, Muller-Forell W. Anatomy of the visual system. Eur J Radiology 2004; 49, 8-30.
T1
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T2 MRI Imaging of the Visual PathwaysMichael Tibbetts, 2008Gillian Lieberman, MD
Optic tract
Archcortex
Optic nerveAmygdolo- claustral area
Optic tract
Archcortex
Optic radiation
www.e-anatomy.org
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Patient RR: Head MRI 6/2007
“No evidence of acute infarct, mass effect, or hydrocephalus.”
Student Name, yearGillian Lieberman, MD
T1 Transverse BIDMC, PACS, 2007 T1 Sagittal BIDMC, PACS, 2007
Optic Nerve
Optic Chiasm
Requisition: “loss of vision left eye”
Occipital cortex
Optic chiasm
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Patient RR: MR Angiogram 6/2007
Michael Tibbetts, 2008Gillian Lieberman, MD
“No evidence of vascular occlusion or stenosis” BIDMC, PACS, 2007
Basilar artery
Internal carotid artery
Vertebral artery
Anterior cerebral artery
Next: Further Testing for Evaluation of Vision Loss
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Further Testing: Visual Fields and Optical Coherence Tomography (OCT)
Michael Tibbetts, 2008Gillian Lieberman, MD
• Significant superior and temporal field loss OS
• Optical coherence tomography (OCT) of the optic nerves demonstrated definite nerve fiber layer losses OS and questionable thinning of optic nerve OD
• Findings suggestive of “compressive lesion” by neuro- ophthalmologist despite initial negative imaging
OS OD
Courtesy of Nurhan Torun, M.D., 2007
Next: Further Imaging of the Visual Pathways in Patient RR
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Patient RR: C+ MRI of Orbit and Head 12/2007
Michael Tibbetts, 2008Gillian Lieberman, MD
T1 Transverse Pre-contrast T1 Transverse Post-contrast BIDMC, PACS, 2007
Enhancing lesion w/ well-circumscribed marginsDDx: meningioma, pituitary macroadenoma, hemangiopericytoma
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Planum Sphenoidale Meningioma
Michael Tibbetts, 2008Gillian Lieberman, MD
• Meningioma of the dura of the planum sphenoidale: lying on the midline posterior to the olfactory nerve meningiomas and anterior to the tuberculum sella meningiomas
• Planum sphenoidale forms the roof of the sigmoid sinus
• Peak incidence at age 45, 2:1 female• Isointense or hypointense on T1 MRI, intense
enhancement w/ contrast• Small lesions and those isointense may be
difficult to pick up on MRI• Focal areas of nonenhancement within the
tumors may be present representing areas of hemorrhage, scar, cyst, or necrosis.
T1 Sagital Post-Contrast BIDMC, PACS, 2007
Mass extends from sella/suprasellar region w/ involvement of cavernous sinuses, but normal cartoid flow
Patient RR: C+ T1 Head MRI 12/2007
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Was the lesion missed in the original head MRI?
Michael Tibbetts, 2008Gillian Lieberman, MD
T2 Transverse BIDMC, PACS, 2007
Incorrect imaging study was ordered for “Vision loss left eye”.
Orbital cuts and contrast enhanced images not evaluated.
Lesion evident on original MRI, but did not enhance without contrast
Patient RR: T2 Head MRI 6/2007
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Treatment of Planum Sphenoidale Meningioma
Michael Tibbetts, 2008Gillian Lieberman, MD
Surgical resectionTransphenoidal or transcranial approaches10-40% have worsening of vision25-80% have improvement in visual function
Radiation therapyMay halt growth of tumorLess ideal than surgery because radiation does not remove pressure on optic nerve or chiasmProton beam radiotherapy – less scatterCyberknife
No treatment – follow with imagingNot recommended given visual deficit, but Patient RR opted for no intervention
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Role of Imaging in Following TumorMichael Tibbetts, 2008Gillian Lieberman, MD
OS OD
Courtesy of Nurhan Torun, M.D., 2008
9/2007
5/2008
Tumor unchanged in volume by MRI, but increased visual field loss in superotemporal right eyeBIDMC, PACS, 2008
Patient RR: C+ T1 Head MRI 9/2008
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Summary• Patient RR diagnosed w/ planum sphenoidale
meningioma after presenting with vision loss in left eye
• Lesion not detected initially because correct study not ordered.
• Order physician must select imaging of visual pathways based on possible location of lesion.
Vision loss in only one eye -> pre-chiasmalVision loss in both eyes -> chiasmal, post-chiasmal
Michael Tibbetts, 2008Gillian Lieberman, MD
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References• Lavidor M, Walsh V. The nature of foveal representation. Nature Reviews
Neuroscience 2004; 5, 729-735. • Riordan-Eva P, Whitcher JP. Vaughan and Asbury’s General Ophthalmology 2004,
pages 259-280. • Wichmann W, Muller-Forell W. Anatomy of the visual system. Eur J Radiology 2004;
49, 8-30.• Riordan-Eva P. Clinical assessment of optic nerve disorders. Eye 2004; 18, 1161-1168.• Nozaka K et al. Effect of early optic canal unroofing on the outcome of visual functions
in surgery for meningiomas of the tuberculum sellae and planum sphenoidale. Neurosurgery 2008; 62, 839-846.
• Mohit A et al. A large planum sphenoidale meningioma with sinonasal extension in a child. Case report and review of the literature. Pediatric Neurosurgery 2003; 39, 270- 274.
• Digital Journal of Ophthalmology. www.djo.harvard.edu. Accessed on 9/21/2008. • Interactive Atlas of Anatomy. www.e-anatomy.org. Accessed on 9/21/2008.
Michael Tibbetts, 2008Gillian Lieberman, MD
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Acknowledgements
• Nurhan Torun, MD• Aarti Sekhar, MD• Gillian Lieberman, MD• Maria Levantakis• Larry Barbaras
Michael Tibbetts, 2008Gillian Lieberman, MD