HPA 1 Exam 3 - Sensory Facial/Visual Alterations

Bell's palsy

Acute unilateral facial nerve paralysis involving cranial nerve VII

Cranial nerve VII Facial nerve

Controls muscles of facial expression and carries taste sensation from the anterior two thirds of the tongue

Bell's palsy pathophysiology

Inflammation of the facial nerve causes compression within the facial canal leading to facial weakness

Bell's palsy risk factors

Pregnancy diabetes hypertension obesity preeclampsia and recent viral infection

Bell's palsy hallmark finding

Sudden unilateral facial paralysis affecting the entire side of the face

Hyperacusis

Increased sensitivity to sound caused by facial nerve dysfunction

Lagophthalmos

Inability to completely close the affected eye

Bell's palsy treatment

Corticosteroids started early to reduce inflammation

Eye protection in Bell's palsy

Artificial tears eye ointment and eye patch prevent corneal injury when eyelid closure is impaired

Trigeminal neuralgia

Disorder of cranial nerve V causing recurrent episodes of severe facial pain

Cranial nerve V Trigeminal nerve

Provides sensation to the face and controls muscles of mastication

Trigeminal neuralgia pathophysiology

Compression or demyelination of the trigeminal nerve causes abnormal pain transmission

Trigeminal neuralgia pain

Sudden stabbing electric shock like facial pain

Trigger points

Areas of the face where light touch may trigger trigeminal neuralgia pain

Common trigeminal neuralgia triggers

Chewing talking brushing teeth shaving washing the face and touching the skin

Carbamazepine Tegretol

First line medication for trigeminal neuralgia that stabilizes nerve firing

Serious adverse effect of carbamazepine

Aplastic anemia requiring CBC monitoring

Microvascular decompression

Surgical procedure that relieves pressure on the trigeminal nerve when medications fail

Bell's palsy vs trigeminal neuralgia

Bell's palsy causes facial weakness while trigeminal neuralgia causes facial pain without paralysis

Macula

Portion of the retina responsible for central vision and detailed visual acuity

Rods

Photoreceptors responsible for vision in dim light and peripheral vision

Cones

Photoreceptors responsible for color vision and sharp central vision

Aqueous humor

Fluid in the anterior eye that nourishes structures and maintains intraocular pressure

Vitreous humor

Gel like substance that maintains the shape of the eye

Intraocular pressure IOP

Pressure created by aqueous humor within the eye

Accommodation

Change in lens shape that allows focusing on near and distant objects

Age related macular degeneration AMD

Progressive degeneration of the macula causing loss of central vision

Drusen

Lipid and protein deposits beneath the macula characteristic of dry AMD

Dry AMD

Gradual atrophy of macular cells caused by drusen accumulation

Wet AMD

Growth of abnormal leaky blood vessels beneath the retina causing rapid central vision loss

Neovascularization

Formation of abnormal blood vessels seen in wet AMD

Anti VEGF therapy

Intravitreal medication that inhibits abnormal blood vessel growth in wet AMD

Photodynamic therapy

Laser treatment used to destroy abnormal retinal blood vessels in wet AMD

Amsler grid

Screening tool used to detect distortion of central vision in macular degeneration

Metamorphopsia

Visual distortion in which straight lines appear wavy commonly seen in AMD

Fundoscopic examination

Dilated retinal examination used to evaluate the macula optic nerve and retina

Cataract

Clouding of the lens causing progressive blurred vision

Cataract pathophysiology

Lens proteins break down and clump together causing loss of transparency

Cataract manifestations

Blurred vision glare halos around lights decreased night vision and cloudy lens

Cataract surgery

Removal of the cloudy lens with placement of an artificial intraocular lens

Postoperative cataract teaching

Avoid increasing intraocular pressure use prescribed eye drops and report sudden pain or vision loss

Glaucoma

Progressive optic nerve damage usually associated with increased intraocular pressure

Open angle glaucoma

Chronic painless glaucoma caused by decreased drainage through the trabecular meshwork

Angle closure glaucoma

Acute painful glaucoma caused by sudden blockage of aqueous humor drainage

Hallmark of open angle glaucoma

Gradual peripheral vision loss with few early symptoms

Hallmark of angle closure glaucoma

Sudden severe eye pain blurred vision halos nausea vomiting and red eye

Tonometry

Test that measures intraocular pressure

Perimetry

Visual field test used to detect peripheral vision loss

Optic nerve damage

Irreversible vision loss caused by prolonged elevation of intraocular pressure

Prostaglandin analogs

Glaucoma medications that increase aqueous humor outflow and lower intraocular pressure

Beta blockers for glaucoma

Medications that decrease aqueous humor production to lower intraocular pressure

Carbonic anhydrase inhibitors

Medications that reduce aqueous humor production in glaucoma

Cholinergic agonists

Medications that increase aqueous humor outflow by constricting the pupil

Rho kinase inhibitors

Glaucoma medications that improve aqueous humor drainage

Central vision loss

Hallmark finding of macular degeneration

Peripheral vision loss

Hallmark finding of glaucoma especially open angle glaucoma

Cataracts vs glaucoma vs AMD

Cataracts cause cloudy vision glaucoma damages the optic nerve and AMD destroys central vision

Dry vs wet AMD

Dry AMD progresses slowly while wet AMD progresses rapidly because of neovascularization

Open angle vs angle closure glaucoma

Open angle is chronic and painless while angle closure is acute painful and an ophthalmic emergenc