Review of Giant Cell Arteritis

The Bottom Line: Giant Cell Arteritis is the prime medical emergency in ophthalmology because it may result in loss of
vision in 1 or both eyes. This vision loss is preventable if patients are diagnosed early and treated immediately with high doses of corticosteroids.

Waldman, Corey W, Steven D Waldman, and Reid A Waldman. “Giant cell arteritis.” The Medical clinics of North America 97.2 (2013):329-335.

The mean age of onset is approximately 70 years; the condition is rare in those younger than 50 years. Women are affected about 3 times as often as men. The onset can be dramatic but is usually insidious. Corticosteroids are mandatory in the treatment of Giant Cell Arteritis; they reduce the incidence of complications, such as blindness, and rapidly relieve symptoms. Nonsteroidal antiinflammatory drugs lessen the painful symptoms

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How does bitemporal hemianopia differ from the visual field defect known as tunnel vision?

Bottom line:  Bitemporal hemianopia results from a chiasmal lesion and causes “blindness in the lateral or temporal half of the visual field for each eye.”  The symptom described as tunnel vision refers to a constricting of the visual field all the way around, not just on the lateral half.  Tunnel vision is associated with diseases such as glaucoma, effects of various drugs including alcohol and hallucinogens, and biological responses to high acceleration, hypoxia, and blood loss.

Details:  See eFigure 7-3, Visual Loss.  In: Current Medical Diagnosis and Treatment [AccessMedicine].    #3 illustrates field loss in bitemporal hemianopia.  Tunnel vision is not depicted in this figure.

Visual system clinical correlations.  In:  Clinical Neuroanatomy [AccessMedicine].

Tunnel vision.  In: Wikipedia.  Illlustrates the affect on the visual field and lists medical and biological causes of tunnel vision.

What is the evidence for use of intrathecal amphotericin in treating cerebral mucormycosis?

Bottom line:  There are only case reports on use of intrathecal amphotericine to treat cerebral mucormycosis.

Pediatr Neurosurg. 2003 Apr;38(4):212-5
Aust N Z J Med. 1990 Feb;20(1):74-7
Arch Neurol. 2009 Feb;66(2):272-3.
Neurosurgery. 1998 Mar;42(3):644-8
Clin Infect Dis. 1994 Dec;19(6):1133-7.
Neurosurgery.  1999 Dec; 45(6):1461-3.
Clin Infect Dis. 1995 Nov;21(5):1352.
Hematology.  2003 Apr; 8(2):119-23.
Arch Intern Med 1983; 143:581-3
Ann Intern Med 1979; 19:655.

What structures of the eye are part of the uvea? How can you differentiate between uveitis and scleritis?

Bottom line: Uveitis affects the structures of the uveal tract, which includes the iris, ciliary body and choroid and which supplies blood to most of the eye.  Findings in uveitis may include a rim of hyperemia around the limbus (“ciliary flush”), adhesions of the iris (synechiae), eye pain.  Findings vary based on the cause and specific location of inflammation.   Findings in scleritis include a deep red color of the sclera going deep to the conjunctiva in the sclera.

More details:

    • Image of anterior uveitis.  In:  Atlas of Emergency Medicine [AccessEmergencyMedicine].
    • Uveal tract.  In: Vaughan & Asbury’s General Ophthalmology. [AccessMedicine]  Diagram of uveal tract and review of causes and clinical findings of anterior, intermediate and posterior uveitis
    • Uveitis, Anterior.  In:  VisualDx           Summary of diagnostic findings and differential diagnosis
    • Scleritis, Diffuse.  In:  VisualDx.         Image and diagnostic findings common in  scleritis

What are the physical exam findings of acute angle glaucoma?

See examples of acute closed-angle glaucoma in AccessMedicine and MDConsult.  According to Physical Section of Glaucoma topic in DynaMed, and Glaucoma, Acute Angle-Closure topic in AccessMedicine, findings include
red eye
moderately dilated pupil
cloudy cornea
elevated intraocular pressure (according to AccessMedicine, > 50 mm Hg, producing hard eye on palpation)
shallow anterior chamber
closed angle by gonioscopy

Other clinical findings can include  severe ocular pain, blurred vision, halos around lights, nausea, vomiting