Cavernous Sinus

Question 1

Cavernous sinus fistula

Answer 1

Result of abnormal communication between the AV systems. High pressure blood demo the carotid artery builds up with inthe cavernous sinus, preventing the return of venous blood from the globe of the eye; this reuslts in the classic unique triad of chemosis, pulsatile proptosis, and ocular bruit. Can be caused by trauma. Can be assoacited with high IOP, headaches, EOM trstrictions. Opthalmoplegia (CN 6 palsy) occurs in 50% of CFF

Question 2

Most common cause if unilateral or bialteral proptosis in young or middle aged patients

Answer 2

TED

Question 3

What is TED

Answer 3

AI disease characterized by TSH receptors autoABs directed against the EOMs and soft tissue within the orbit. Similar to patients with CFF, may have EOM restrictions. Fibrosis of the MR can resutls in an abduction deficits, mimicking a 6th nerve palsy

• unlike CFF, proptosis secondary to TED is not pulsatile and does not classically have a rapid onset
• if conj chemosis is present in TED, it is typically mild and no assocaited with an increase in IOP in the invovled eye
• patients with EOM restrictions secondary to TED will habe a positive forced duction test, in contrast to ophthalmoplegia resulting from CFF

Question 4

Thyroid function and TED

Answer 4

30-70% of patients with TED have abnormal thyroid function, most commonly hyperthyroidism; patients may reports a Hx of systemic symptoms including heart palpitations, weight loss, heat intolerance, and/or hair loss

Question 5

Orbital pseudotumor

Answer 5

Idiopathic inflammation of the soft tissues and muscles in the orbit. Characterized by a sudden onset, unilateral, painful proptosis in young to middle aged patients. It may also be associated with conjunctival chemosis and hyperemia, eyelid edema and hyperemia, EOM restrictions, decreased corneal sensation (V1), and an increased IOP on the invovled side. In general, patietns have decreased VA in the affected eye due to compression of the ONH

Question 6

Chemosis

Answer 6

Typically bilateral and associated with allergic symptoms. If a patient presetns with unirlateral chemosis WITHOUT allergic symptoms, consider idiopathic orbital pseudotumor, esp in patietns 20-50yo

Question 7

Orbital cellulitis

Answer 7

Infection posterior to the orbital septum. Leading cause of exophthlamos in kids. The classical presentation includes unilateral proptosis, eyelea edema, pain, and/or restrictions on eye movements causing diplopia, fever, decreased vision due to ONH compression (an APD will be present), and conjunctival chemosis and hyperemia. Potential etiologies include sinus infections (ethmoid), orbital infections, dental infections, orbital trauma, or previous ocular surgeries

Question 8

Anterior encephalocele

Answer 8

Rare neural tube defect resulting in malformation of the bones of the skull, leading to increased risk of cerebrum protrusion from the skull. The brain and tissue and meninges may protrude anteriorly or posteriorly within the skull. Anterior encephalocele is typically associated with a better prognosis because it is less leaky to contain brain tissue (compared to posterior). It may result in a pulsatile proptosis that worsens when newborns cry; there is no thrill or ocualr bruit

Question 9

CFFs causes

Answer 9

Spontaneously (ruptured carotid artery aneurysm), from associated cavernous sinuspatholgoy, or from recent trauma. 77% of CFFs result from closed head trauma

Question 10

Diagnosing CFF

Answer 10

MRI and angiography

-asymmetrically enlarged cavernous sinus or superior ophthalmic vein

Question 11

What condition is assocaited with minocyline

Answer 11

Pseudotumor cerebri

Question 12

Treatment for CFF

Answer 12

Balloon embolization for high flow CFFs

Low flow observed without treatment, unless vision or life threatening situations develop

Question 13

Dx and Tx of TED

Answer 13

Evaluation includes a CT scan of the orbits and blood work for thyroid function (T3/T4/TSH)

• the orbital CT scan will show enlargement of the bodies of the EOMs, WITHOUT tendon involvement (orbital pseudotumor involves tendon)
• bc pts with TED most often have hyperthyroidism, T3 and T4 values are often elevated and TSH levels are low (due to negative feedback loop between the thyroid and the pituitary glands). An endocrinology consult is warranted in patietns with confirmed TED

Question 14

TED complications

Answer 14

Exposure keratopathy
SLK
Optic neuropathy
Restrictive myopathy

Question 15

Treatment of SLK and exposure Keratopathy from TED

Answer 15

ATs, Mucomyst, punctal occlsuon, taping lids at bedtime, and/or lateral tarsorrhaphy or canthorrhaphy

Question 16

Tarsorrhaphy

Answer 16

Procedures in which the upper and lower eyelids (lateral) are sewn together in order to reduce the size of the palpebral aperture to limit exposure of the ocular surface.

Question 17

Canthorrhaphy

Answer 17

Shortening of the palpebral fissure of the eyelids by suturing the canthus. Although a tarsorrhaphy is very simialr, it is not restricted to the medial or lateral canthi, as it may involve the middle portion of the eyelid

Question 18

Treatment of optic neuropathy from TED

Answer 18

Immediate treatment with oral steroids (pre 100mg QD for 2-14 days) or radiotherapy (less common) in order to reduce inflammation of the EOMs and orbital soft tissue. Orbital decompression surgery may be indicated if oral steroid treatment is contraindicated or ineffective

Question 19

Treatment of restrictive myopathy from TED

Answer 19

Confirmed with forced duction test

• inferior and medial most commonly affected
• treatment is orbital decompression, followed by strab surgery

Question 20

Graves and smoking

Answer 20

Sig increased risk of ophthalmic complications in patients with Graves’ disease (2-9x greater risk). Patients should be encouraged to stop smoking. Also recall that 1% of patietns with TED have or will develop MG

Question 21

Orbital pseudotumor Dx and Tx

Answer 21

Orbital CT scan indicated and will show enlargement of bodies and tendons of EOMs

Treated with systemic steroids (oral pred 60-100mg QD for 2-3 weeks, with slow taper) leading to significant improvement in the first 24-48 hours; if does not respond in the first 48 hours, consider alternative DX

Question 22

What should always be RXed in combo with high dose steroids

Answer 22

H2 PPIs

Question 23

Orbital cellulitis DX

Answer 23

ENT tissue diagnosis of the sinuses and rule out fungal phycomycosis. Immunocompromised patients or patients with DM with orbital cellulitis can develop mucor, an aggressive and potentially life threatening fungal infection

Question 24

Treatment for orbital cellulitis

Answer 24

Immediate hospitalization for a 1 week treatment with IC ABX, commonly ceftriaxone and naficillin, after improving on IV ABX therapy, patients are started on a 10 day course of oral abx such as augmentin 250-500mg TID, Ceclor 250-500mg TID, or Bactrim 1 double strength tablet QD (allergic to PCN)
-topical abx ointments indicated for concurrent conjunctivitis or corneal exposure

Question 25

Anterior encephalocele dx

Answer 25

Prenatal ultrasound, refer to neurosurgery for consultation and treatemnt