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General Medical Officer (GMO) Manual: Clinical Section Ocular Emergencies Department of the Navy Bureau of Medicine and Surgery Peer Review Status: Internally Peer Reviewed (1) This section does not attempt to duplicate the material in the references listed at the end of this section. Rather, it outlines special considerations in the management of several ocular emergencies by the operational medical officer. Understandably, all recommended treatments may not be possible in some locations. Frequently this occurs in a remote area where immediate consultation or MEDEVAC is an impossibility. Purchase and use of one or both of the listed texts is strongly recommended. The first reference is a particularly good practical guide. Both should be consulted for detailed information on evaluation techniques and specific treatment regimes. Visual acuity should be obtained before initiating treatment in all ocular conditions except chemical burns where irrigation must be started immediately. (2) General (a) History The ocular history should include date and time of onset of symptoms, any precipitating events, any past eye surgeries or disease, use of corrective lenses, and any associated symptoms. (b) Ocular exam Visual acuity If a Snellen chart is not available, use a pocket-sized near vision card, or any other printed material (i.e., newspaper). The patient should wear their glasses for this exam. If the patient wears corrective lenses and they are unavailable have them look with one eye at a time through a pinhole (made by sticking a pin or needle through a 3 x 5 card). The pinhole effect serves to eliminate most of the optical aberrations of a patient’s refractive error, thereby giving the examiner a reasonable estimate of the patient’s visual potential even if their glasses or contact lenses are not available. Pupil exam To rule out afferent pupillary defect, perform the swinging flashlight test by moving the light back and forth from one eye to the other, pausing at each eye for a couple of seconds (use the count of one, one thousand etc.) to observe the pupil. In the normal exam, the illuminated pupil should constrict and then show some slight enlargement. Any asymmetry between the eyes in constriction or escape constitutes a relative afferent pupillary defect. Ocular motility Up, down, left, right, and 45 degrees between each direction (gaze up and out, gaze up and in, etc.) Assess visual fields by confrontation Sit facing the patient, with the patient and yourself covering opposite eyes (patient’s left eye, examiner’s right eye). You should hold up fingers from each hand and have the patient count the total. Repeat in different meridians. External and anterior segment exam (a) If a penlight is available, check for conjunctival injection or blanching, corneal opacities, and anterior chamber depth. (b) If a slit lamp is available, examine the lids, lashes, conjunctiva, cornea, anterior chamber, iris, and lens. Fundus exam If this exam is difficult, dilate the pupil with Tropicamide 1%, 1 gtt. Neosynephrine 2.5%, 1 gtt can be used in addition to Tropicamide to facilitate pupil dilation. If a corneal laceration or a post-surgical wound leak is suspected, perform a Seidel test by touching a fluorescein strip, moistened with topical anesthetic, directly to the area of suspected perforation. (a) When viewed with a white light, a leak of aqueous will appear as a greenish-yellow stream flanked by dark orange or blackish nonfluorescing dye. (b) When viewed with a Woods Lamp or the blue beam of a slit lamp, a leak will appear dark, with greenish-yellow staining on either side. (3) Specific Conditions (a) Ruptured globe (1) Etiology (a) Blunt trauma with rupture. (b) Missile injury with or without retained intraocular foreign body. (2) Signs and symptoms. In some cases, the rupture site may not be readily apparent. A high index of suspicion must be maintained in evaluation of ocular trauma. (a) Conjunctival edema, chemosis, or hemorrhage. (b) Hyphema. (c) Limitation of extraocular motility. (d) Obvious rupture of cornea or sclera. (e) Uveal tissue (iris, ciliary body) exposed or prolapsed. (3) Management (a) Avoid direct pressure to the globe at all times. (b) Tetanus toxoid (0.5 cc IM) if not up to date. (c) Parenteral broad spectrum antibiotics (Cefazolin 1 g IV q8h and Gentamycin 1.5 mg/kg loading then 1 mg/kg q8h). Do not use any topical medicines in a potentially ruptured globe. (d) Protect traumatized eye with a Fox shield. If no aluminum shields are available, the bottom half of a Styrofoam cup can be taped in place over the eye. (e) Urgent MEDEVAC - surgical repair should be accomplished as soon as possible, and not later than 24 hours from the time of trauma. (f) Consider mild analgesics and antiemetics as needed to avoid Valsalva maneuvers. (g) Keep patient NPO (nothing by mouth), if possible. (h) Bed rest, use a mild sedative if necessary. (i) If an intraocular foreign body is suspected, the patient will eventually need x-rays and an orbital computed tomography (CT) with coronal sections. Magnetic Resonance Imaging (MRI) should be avoided due to the high probability that the foreign body may have magnetic properties. (b) Chemical Burns (1) Etiology: chemical exposure of eye (2) Signs and symptoms (a) Corneal epithelial defects or opacification (b) Injection or blanching. (c) Chemosis (conjunctival edema) (d) Any of the above signs may be associated with pain, tearing, and photophobia (3) Management (a) Do not waste time taking a detailed history or performing an eye exam. Begin immediate, copious irrigation with at least 2 liters of eyewash, normal saline, water, (whichever is fastest), for a period of more than 30 minutes. Use a paperclip to roll out (evert) the upper and lower lid so as to irrigate any chemical or particulate matter that may be trapped in the fornices. A dampened Q-tip (cotton-tipped applicator) can be used to remove small foreign bodies and/or particulate matter. (b) Five minutes after stopping irrigation check the pH of the inferior cul-desac. Continue irrigation until the pH is neutralized at 7.0. (pH papers = NSN 6640-00-442-9005, but a urine dip stick will work). (c) Topical anesthesia or lid retractors may be necessary (paper clips can be opened into an elongated S shape, with will suffice for lid retractors). (d) A commercially available irrigation kit (Eye Irrigator, FSN 6515-01-4582634) is available to facilitate irrigation of the eye and clear the fornices. It is important to fully irrigate the fornicies because these can trap and harbor residual chemicals. (e) After the pH is neutral, cycloplege with Scopolamine 0.25% 1 gtt, antibiotic ointment, pressure patch for 24 hours, and oral pain medications as needed. (4) Types of chemical injury (a) Acid - damage immediate and nonprogressive. (b) Alkali - progressive tissue destruction will result in loss of vision and loss of the eye if not promptly and adequately irrigated. (5) Topical antibiotics (Sulfacetamide, Erythromycin or Ciprofloxacin, 1 gtt TID.). (6) Cycloplegia (Cyclogyl 1% QID, Scopolamine 0.25% TID). (7) Oral analgesics. (8) Urgently MEDEVAC the patient if blanching and/or corneal opacification is present. (c) Central Retinal Artery Occlusion (CRAO) (1) Etiology (a) Arteritic (temporal arteritis). (b) Nonarteritic (embolic, atherosclerotic). (2) Signs and symptoms (a) Acute, profound, painless loss of both central and peripheral vision in the affected eye. (b) Marked visual field defect (test by confrontation). (c) Afferent pupillary defect (test by swinging flashlight). (d) Fundus: arteriolar attenuation, cherry red spot, optic nerve pallor. (e) Note: total retinal destruction begins within 90 minutes of total occlusion many patients don't present until several hours after onset; prognosis is extremely poor. (3) Treatment (usually not effective but should be attempted). (a) Keep the patient lying flat. (b) Massage globe: 15 seconds of firm digital pressure, followed by 5 seconds of sudden release, repeat over a 10 to 15 minute time frame. (c) Acetazolamide 250 mg x 2 by mouth, as a one time dose. (d) Have the patient breathe into a paper bag; increased CO2 acts as a vasodilator and may increase perfusion. (e) If temporal arteritis is a possibility (i.e., patient older than 55 along with other symptoms consistent with the diagnosis), begin high dose pulse steroids (1 gm Solumedrol IV q12 hours followed by 100 mg Prednisone by mouth daily). Obtain an erythrocyte sedimentation rate (ESR). (f) MEDEVAC is appropriate (but not emergent). (d) Acute Glaucoma (1) Etiology. Angle closure (also referred to as narrow angle glaucoma in some references). The cause is an anatomic predisposition in some patients, whereby the peripheral iris/cornea interface is narrowly separated and prone to blocking and closing off flow of aqueous humor fluid from the anterior chamber into the trabecular network (i.e. the drain). This causes an acute rise in intraocular pressure. (2) Signs and symptoms: (a) Red, painful eye (b) Cloudy cornea due to increased intraocular pressure. (c) Mid-dilated, fixed pupil (d) Variable afferent pupillary defect (e) Steamy vision, halos around lights (f) Decreased visual acuity (variable) (3) Management (DO NOT pharmacologically dilate a patient that is suspected to have this condition or with a known history of this condition in the past). (a) Check intraocular pressure with a Schiotz tonometer or a slit lamp with applanation tonometer. (b) MEDEVAC urgently; initiate treatment pending transport. (c) Topical beta-blockers x 1 dose (Timolol 0.5%, Levobunolol 0.5% or Betimol 0.5%). (d) Carbonic anhydrase inhibitor x 1 dose (Acetazolamide 250-500 mg IV or 250 mg by mouth). (e) Osmotic agent (Isosorbide 50 to 100 orally or Mannitol 1-2g/kg IV over 45 minutes. Note: 500 cc of Mannitol 20% contains 100 grams of Mannitol may be repeated every 6 hours. (f) Pilocarpine drops 1-2% Q 15 minutes x 2, use one drop of Pilocarpine in the fellow eye x 1 to reduce the possibility of bilateral angle closure. (g) Recheck intraocular pressure in one hour after performing instructions (c) – (f), and every hour thereafter until the MEDEVAC is completed. (h) If pressure has been reduced to less than about 30mmHg, continue Pilocarpine 1% QID OU. If intraocular pressure is still more than 30mmHg consider the following regimen (in addition to Pilocarpine 1% QID OU). (1) Topical beta-blocker 1 gtt every 12 hours to the affected eye, and (2) brimonidine tartrate (Alphagan) 1 gtt every 12 hours to the affected eye, and (3) apraclenidine (Iopidine 0.5%), 1 gtt every 8 hours to the affected eye, and (4) systemic carbonic anhydrase inhibitor (Acetazolamide), 250 mg PO QID or 250 mg IV QID. (e) Retinal Detachment (1) Etiology (a) Retinal hole or tear (b) Exudative (tumor, inflammation) (c) Tractional (inflammation, diabetic) (2) Signs and Symptoms (a) Painless decreased visual acuity (b) Flashing lights (photopsias) (c) Floaters (entopsias) (3) Management (a) Bed rest with HOB elevated. (b) Referral to a facility with ophthalmologist or optometrist on site to perform a detailed exam. (c) Keep patient NPO. (f) Hyphema (1) The etiology is blunt or penetrating trauma. (2) Signs and symptoms: (a) Blood in the anterior chamber. (b) Possibly increased intraocular pressure (IOP). (c) Photophobia. (d) Decreased visual acuity. (3) Management (a) Strict bed rest with HOB elevated to 30 degrees. This allows for the blood to settle inferiorly and clear the visual axis. (b) Apply Fox shield (not a patch) to protect eye. (c) Dilating drop (Atropine 1% TID, or Scopolamine 0.25% TID). This prevents movement of the iris, which could contribute to more bleeding (d) Sedatives, analgesics (NOT ASA), antiemetics and laxatives as necessary to prevent Valsalva. (e) MEDEVAC urgently (pressure rise, rebleeding, corneal staining, and retinal detachment can be serious complications). (f) Check for sickle cell disease. (g) Consider Amicar 50 mg/kg PO q4h (maximum 30g/day) for 5 days after initial episode or rebleed. (g) Orbital Cellulitis (1) Orbital cellulitis (a) Etiology (1) Extension from sinusitis (esp. ethmoid) (2) Orbital trauma (3) Extension from dental infection (4) Occasionally results following the spread of a skin infection (i.e. preseptal cellulitis) (b) Signs and symptoms (1) Periorbital edema and erythema. (2) Chemosis. (3) Decreased motility or pain with extraocular movement. The patient may or may not have proptosis. (4) Decreased visual acuity. (variable) (c) Management (1) Immediate, high dose, parenteral antibiotics: (a) Ceftazidime 1 to 2 g IV every 8 hours (b) plus Nafcillin 1 to 2 g IV every 4 hours. (2) MEDEVAC urgently (3) If available obtain sinus series, once hospitalized patient will also require orbital CT with coronal sections and possible ENT evaluation. (2) Preseptal cellulitis (a) Etiology (1) Localized infection (sty) that has spread. (2) Trauma. (3) Sinusitis. (b) Signs and symptoms (1) Periorbital edema and erythema (2) In contrast to orbital cellulitis, extraocular motility is full, vision is usually normal, no afferent pupillary defect (APD) or proptosis is present. (c) Management (1) If mild, Amoxicillin/Clavulanate (Augmentin) 250 mg PO TID or Dicloxacillin 250 mg PO BID, or Amoxicillin 250 mg PO QID, or Azithromycin (Z-pack), 5 day supply. (2) If severe or <5 age, IV antibiotics as described for orbital cellulitis. (3) Warm compresses. (4) Tetanus toxoid as needed. (5) Follow closely for evidence of the development of orbital cellulitis, or localized abscess that would merit incision and drainage (I&D). (h) Corneal Ulcer (1) Etiology. Bacterial, fungal, viral, acanthamoeba, contact lens (2) Signs and symptoms: (a) Red, painful eye (b) Focal white opacity in corneal stroma with overlying epithelial defect (c) Photophobia (d) Decreased visual acuity (variable) (e) Discharge can vary from none, to thin mucus or occasionally purulent. (3) Management (a) MEDEVAC urgently. (b) Obtain conjunctival culture with cotton swab prior to starting antibiotics. (c) Remove contact lens if present, culture lens case and lenses in contact wearers. (d) Begin frequent, topical, broad-spectrum antibiotics; (there is no role for oral or IV antibiotics). A good of antibiotic would be Ciprofloxacin (Ciloxam 0.3% solution), 1 gtt every 30 minutes until ophthalmologic evaluation. If the ulcer is >3mm in diameter and in the visual axis, consider fortified antibiotics (requires pharmacy services); Ancef 50mg/ml, 1 gtt every 1 hour, and Gentamycin 14mg/ml, 1 gtt, every 1 hour. (e) Cycloplegia (Cyclogyl 1% top TID, Scopolamine 0.25% top TID). (f) Oral pain medication as needed. (i) Blowout Fracture (1) Etiology. Trauma to globe or orbital rim (2) Signs and Symptoms (a) Periorbital edema and ecchymosis. (b) Restricted extraocular movement (especially upgaze). (c) Hypesthesia of infraorbital nerve. (3) Management (a) Erythromycin (250 mg po QID) as prophylaxis for orbital cellulitis. (b) MEDEVAC within a week of injury - surgical repair usually delayed 72 hours to 10 days and dependent upon persistence of restriction of ocular motility (diplopia), or enophthalmos (due to loss of orbital volume). (c) Will need ophthalmologic evaluation and orbital CT with coronal sections. (j) Other Conditions (1) Anything other than minor ocular conditions should be referred urgently for ophthalmologic evaluation. Direct voice, email, or priority message communication with an ophthalmologist can be invaluable in obtaining assistance when you are in a remote location. If in doubt, refer. (k) Cycloplegic agents (1) Tropicamide 1% - 6 hours duration. (2) Cyclogyl 1% to 2% - 12 hours duration. (3) Homatropine 2% - 24 hours duration. (4) Scopolamine 0.25% - 48 hours duration. (5) Atropine 1% - 14 days duration. (l) Topical antibiotics (1) Ointments last 1 to 2 hours, are more soothing, provide more lubrication, but blur vision up to 1/2 hour. (2) Solutions last 15 to 30 minutes, do not blur vision. (3) Low toxicity antibiotics. These are good first line drugs for minor ocular conditions. (a) Ciprofloxacin drops (b) Bacitracin ointment (c) Erythromycin ointment (d) Sodium sulfacetamide drops (4) High toxicity antibiotics. These are best reserved as second line drugs. (a) Neosporin ointment and drops (b) Gentamycin ointment and drops References (a) Wills Eye Manual, Office and Emergency Room Diagnosis and Treatment of Eye Disease, R.D. Cullom, c. 1994, J.B. Lippincott, ISBN 0-397-51380-1. (b) General Opthalmology, Appleton and Lang, D. Vaughn, c.1992, Appleton & Lange, ISBN 08385-3115-6 or 0-891-2084. Chapter revision by CDR Peter Custis, MC, USN, Ophthalmology Specialty Leader, Naval Medical Center San Diego, San Diego, CA, (1999).