Conditions Flashcards
(30 cards)
Muscles affected in TED
(In order - IM SLO)
Inferior rectus, medial rectus, superior, lateral, oblique?
Often leading first to hypotropia and esotropia.
Treatment: orbital decompression followed by strab surgery.
Orbital Pseudotumour
- unilateral, painful proptosis, chemosis, elevated IOP
- young to middle aged
- reduced VA due to ON compression
- restricted EOMs
- CT scan will show inflammation of EOM and tendons
Malignant melanomas commonly arise from?
Dysplastic nevi or tumour metastasis from the lungs (men) or breasts (women).
Early signs of Keratoconus
- Fleischer’s ring (iron deposit)
- Scissors reflex
- irregular mires
- inferior steepening of the cornea
Late signs of Keratoconus
- Hydrops
- Munson’s sign
- Vogt’s striae
What is a corneal ulcer?
Epithelial defect with an underlying infiltrate.
Infectious vs Sterile Corneal Ulcer
- size matters! Larger usually infectious.
Infectious ulcers will have epithelial defects bigger than the infiltrate or about the same size.
Sterile will have a smaller epithelial defect than the infiltrate.
Which bacteria can invade an intact corneal epithelium?
Canadian National Hockey League!!!!
- Corynebacterium diphteria
- Nisseria gonorrhea and meningitidis
- Haemophilus
- Listeria
Asides from trauma, what systemic condition is higher risk for hyphema?
Sick-cell anemia
Test for: CBC, prothrombin/partial thromboplastin time (PT/PTT).
Treatment/management for hyphemas?
- B-scan ultrasound indicated if hyphema blocks view of fundus/risk of retinal detachment
- bedrest with head elevated at 30 degrees to decrease risk of corneal blood staining and IOP rise
Problems with corneal blood staining
5% of patients and typically develops in late stages of hyphema.
Associated with:
- large hyphemas
- elevated IOPs
- compromised corneal endothelial cells
What SHOULD NOT be performed in a patient with hyphema?
Gonioscopy and scleral depression.
- pressure may increase risk of rebleeding.
Gonio should be done when hyphema has resolved.
Commotio retinae
Disruption of the RPE and photoreceptor outer segments due to trauma.
- gray-white discolouration of the retina
- Berlin’s edema when located within the macula
- hyper-reflectivity on OCT photoreceptor outer segment
Typically resolves in 24-48 hours without sequelae. Permanent VA/VF loss may occur.
Sympathetic ophthalmia
Immune mediated response in fellow eye after the other eye undergoes penetrating foreign body/surgery.
Characterized by subretinal infiltrates (Dalen Fuchs nodules), vitritis, serous retinal detachments, and papillitis.
Suspected orbital blow-out fracture should be evaluated for?
- EOM restriction
- crepitus
- vergences
- infraorbital hypoesthesia (decreased sensation of the cheek on the affected side due to damage of the infraorbital nerve)
- step-off
- exophthalmometry
- globe ptosis
- asymmetric monocular PDs
Most common location for an orbital blow-out fracture
Maxillary bone in the orbital floor
Nerve most susceptible to trauma?
CN 4.
Longest course from the brainstem. Can be congenital or acquired palsy:
- neoplasm/aneurysm (10%)
- ischemic (20%)
- undetermined (30%)
- trauma (40%)
Common causes of fungal keratitis
- aspergillus
- fusarium
Candida albicans often occurs in eyes with chronic corneal disease or immunocompromised
Familial adenomatous polyposis (FAP)
Autosomal dominant inherited condition that results in hundreds of polyps throughout the colon in post-puberty patients.
If left untreated, 100% of patients will develop colon cancer (usually by the age of 50).
Refer to internal medicine.
Gardner’s syndrome
Variant of FAP - has multiple CHRPs in the fundus. Triad of multiple intestinal polyps, skeletal hamartomas and soft tissue tumours. 50% of these patients will have dental anomalies.
Refer to internal medicine.
Goldenhar syndrome
Incomplete development of facial structures. Dermoids appear over face - commonly inferotemporal limbus and may involve entire cornea.
Triad:
- ocular dermoids
- preauricular skin tags
- vertebral dysplasia
Crouzan’s syndrome
Craniofacial disorder.
- shallow orbits with PROPTOSIS
- aniridia
- blue sclera
- strabismus
- optic atrophy
- hypertelorism
- congenital cataracts
Congenital encephalocele
Results in proptosis at birth. Increases in proptosis and becomes pulsatile during crying.
Fabry’s disease
X-lined autosomal recessive lysosomal storage disease - mostly in males.
- cornea verticilata
- posterior spoke-like crystalline lens opacities
Patients often report episodes of excruciating pain in the fingers and toes.
- premature death (ages 40-50) from renal or cardiovascular complications
