Foreign Bodies

Foundations

The diagnosis usually is self-evident. Ocular trauma without proper eye protection is the most common history. Foreign bodies are occasionally identified by abnormal ocular examination findings without a stated history of trauma. For example, the cause of reduced vision in an intoxicated patient may be a foreign body ( Fig. 51.1 ). Early diagnosis, care, and follow-up minimize risks, such as endophthalmitis or sight-threatening siderosis bulbi.

Clinical Features

Most patients report a foreign body sensation, even though they cannot see the foreign body. The patient may complain of frequent lacrimation and conjunctival injection. Foreign bodies that have created corneal injury and are no longer present may account for symptoms identical to those noted with a retained foreign body. Occasionally, patients with retained foreign bodies (e.g., malpositioned contact lenses) can present with recurrent conjunctivitis.

An important component of the history is whether radial keratotomy or similar ocular surgery has been performed. Historically, ophthalmologic procedures have been associated with the delayed diagnosis of foreign body entrapment. Although more current literature contains little or no mention of these procedures as foreign body risk factors, the potential for situational relevance (e.g., management of corneal foreign bodies) dictates a need for the emergency clinician to obtain a complete ocular surgical history.

The initial survey includes standard elements of the ED eye examination. Visual acuity at the time of presentation is a consistently reported predictor of ultimate visual outcome. Slit-lamp examination allows the detection of a corneal foreign body by the shadow that it casts on the iris. The slit-lamp may also facilitate the identification of rust rings. Fluorescein can aid in detecting abraded corneal epithelium.

The inner aspects of both lids should be examined. The lower lid can be successfully exposed with gentle manual retraction outward and downward as the patient looks upward. The upper lid can be successfully exposed through eversion, instructing the patient to look downward while upward eyelash traction is applied. During this procedure, an applicator stick can be used to act as a fulcrum on the proximal edge of the tarsal plate. After location and removal of one foreign body, re-examination should occur to evaluate for other ocular foreign objects.

Differential Diagnoses

Selected differential diagnoses of ocular foreign bodies include corneal abrasions, conjunctivitis, iritis, glaucoma, allergic chemosis, and globe perforation.

Diagnostic Testing

If the history and mechanism of injury are compatible with ocular penetration by radiopaque material, or if a small wound of the globe is noted, anteroposterior and lateral radiography of the orbit is typically the initial step to evaluate for deeper penetration into the globe (see Fig. 51.1 ). However, given its advantages in depicting small ocular foreign bodies and complications such as globe rupture, CT is the best initial approach, especially when there is strong clinical suspicion of intraocular penetration. CT has the additional utility of imaging of the intracranial compartment, which is often indicated in cases in which ocular trauma has occurred.

When globe penetration is strongly suspected, fluorescein should be avoided because its application can obscure findings in subsequent physical examination. Fortunately, the incidence of intraocular perforation in the setting of low-velocity (non-explosive) exposures is very low. When perforation is judged unlikely and fluorescein is administered, the identification of rivulets of fluorescein tracking from a puncture (i.e., positive Seidel test) helps identify intraocular penetration.

Ultrasound is a useful adjunct to CT scanning in patients with foreign bodies that are difficult to localize. For patients in whom a foreign body is suspected despite negative ED evaluation, outpatient referral to ophthalmology is recommended because CT, ultrasound, and even MRI have all missed ocular foreign bodies in patients who subsequently developed complications. Given the paucity of reported case series and justifiable concerns about eye damage from the mobilization of ferromagnetic foreign objects, the use of MRI for ophthalmologic foreign body imaging remains controversial. When there is any chance of the presence of a metallic object in the eye, the emergency clinician should not order MRI without consulting both ophthalmology and radiology specialists.

Management

In nearly all cases, therapy is the removal of the ocular foreign body. If the object is located on the bulbar or palpebral conjunctiva ( not the cornea), it often can be removed easily by sweeping the site with a moist cotton-tipped applicator. For small corneal foreign bodies, after application of topical ocular anesthesia, it is often necessary to use an eye spur, small-gauge tuberculin syringe needle, or the edge of an IV catheter (needle removed) to move gently underneath one end of the object and flick or scoop it out. It is prudent for the emergency clinician to avoid significant corneal procedures in patients who have had corneal surgery, such as laser-assisted in situ keratomileusis (LASIK).

After the removal of a corneal foreign body that leaves no rust ring, treatment is essentially the same as for corneal abrasion. When there is a rust ring, ED management should be dictated by standing protocol (designed in collaboration with ophthalmologists) or referred to ophthalmology for removal.

Disposition

If attempts at foreign body removal are not indicated or are unsuccessful, the patient should be referred to ophthalmology for object removal within 24 to 48 hours. Ophthalmology referral should be initiated after removal of metallic foreign bodies because there may be subtle retained fragments or rust rings requiring removal.

Foundations

Otic foreign body extraction can prove problematic, and the difficulty is rarely diagnosis. Instead, with otic foreign bodies, the challenge usually lies in working in a sensitive anatomical region in a patient population that is often uncooperative.

Differential Diagnoses

The selected differential diagnoses of ear foreign bodies include otitis media, otitis externa, ear canal trauma, tympanic membrane perforation, Ménière’s disease, and otologic tumors.

Diagnostic Testing

Diagnostic imaging is rarely required in otic foreign bodies. CT or MRI may be performed to characterize infectious or erosive sequelae.

Management

The treatment for otic foreign bodies is their removal, which should usually occur in the ED. Success rates for ED removal of ear canal foreign bodies vary with patient population and constituent foreign body types.

Even in a very young patient, the presence of a foreign body for more than 1 or 2 days does not constitute an independent risk factor for foreign body removal failure or complication. In the absence of clear contraindications (e.g., obvious tympanic membrane rupture), the emergency clinician should proceed with otic foreign body removal efforts, even in children with objects in the ear canal for a few days.

The patient should be informed about the extreme sensitivity of the auditory passage and the likely discomfort and potential for minor bleeding. Lidocaine instillation may aid in topical anesthesia; liquid 1% or 2% solution is preferred to gel preparations, which impair subsequent visualization.

Infrequently, foreign body removal requires local anesthesia of the external ear canal. The anesthesia instillation procedure may cause patient discomfort and iatrogenic injury if performed in an uncooperative patient. The procedure entails injecting all four quadrants of the canal with lidocaine via a tuberculin syringe inserted through an otic speculum. Given the complexity of local anesthesia to the canal, systemic procedural sedation and analgesia may be preferable.

When the ear canal is inhabited by an insect, it is important to kill or immobilize the creature to facilitate its removal. Any of a number of agents can be used to kill the insect. Topical anesthetics are recommended, and hydrogen peroxide should be avoided because of the risk of injury to the inner ear if there is tympanic membrane perforation. Efficacious formulations include lidocaine as a 10% spray or less concentrated liquid, 2% lidocaine gel, mineral oil with 2% or 4% lidocaine, and alcohol. Alternatively, a novel approach has been recently described in the literature in which a provider may remove a live insect by turning the lights off in the exam room, exert posterior and superior traction on the pinna while pulling forward on the tragus, and shine a bright light source into the ear canal. The light may cause the insect to self-extricate as it tries to avoid illumination.

Several extrication methods may prove effective, and various instruments may be useful. With soft or irregularly shaped objects, it is often possible to grasp the foreign body with forceps (alligator forceps are usually best) and remove it either in one piece or in fragments. If the object cannot be grasped, it may be possible to remove it by passing a blunt-tipped right-angle hook or ear curette beyond the foreign body and gently coaxing it out. Alternatively, a balloon-tipped catheter can be passed distal to the object, with subsequent attempts to withdraw the (inflated) balloon, extracting the object. Any balloon-tipped catheter design may be used as long as its caliber is small enough (about 18-gauge or smaller) to allow comfortable introduction into the ear canal.

Irrigation techniques take advantage of the elliptic shape of the external ear canal. A stream of lukewarm or room-temperature water or saline should be directed at the foreign body’s periphery via a 20-mL syringe and a 14- or 16-gauge catheter; this arrangement has been studied in the laboratory and demonstrated to generate pressures that are well below those required to perforate the tympanic membrane. Irrigation should not be used if there is known history, clinical suspicion, or physical examination evidence of tympanic membrane perforation.

The removal of objects from the middle ear with cyanoacrylate adhesive-tipped swabs is not recommended and carries the risk of contaminating the ear canal with a substance that is difficult to remove and has been associated with ear canal and tympanic membrane injury. When cyanoacrylate has been instilled into the ear, acetone instillation is recommended to facilitate its safe removal.

The removal of otic foreign bodies must be undertaken with care and steadiness. Patient apprehension and sudden movements can risk untoward foreign body movement and avoidable damage to the ear canal.

Otic foreign body sequelae are usually not serious. There are sporadic reports usually related to missed diagnoses and persistent ear canal objects of serious complications ranging from chronic otitis to hearing loss, facial palsy, and deep-seated infections, such as mastoiditis. ^, The most common complications include external ear canal bleeding (10%), otitis externa, and (in about 2% of patients) tympanic membrane perforation. Complications are more likely when the otic foreign body has been in place for prolonged periods, when patients are unable to be cooperative with removal attempts, and when practitioners are less experienced.

After removal of the foreign body, the canal examination is repeated to ensure the lack of retained material and to evaluate otic anatomy. In cases in which the tympanic membrane is ruptured and the middle ear is at risk for infection, appropriate oral and topical antibiotics are recommended.

Disposition

If ED methods of removal are unsuccessful, the patient should be referred to an otolaryngologist within a week. More urgent referral is recommended for cases in which the tympanic membrane is ruptured or in cases where foreign body removal proves particularly traumatic (in such cases, the follow-up is aimed at assessing for external otitis).

Foundations

Although seen less frequently than otic foreign bodies, objects in the nasal passages are still commonly encountered in the ED. Compared with patients with otic foreign bodies, children with nasal foreign bodies tend to be younger, most commonly younger than 5 years old.

ED removal is nearly always successful and with proper technique, serious sequelae are rare. Sedation with agents (such as ketamine) is often necessary. Although evidence is sparse, the overall risk of nasal foreign bodies’ entering the bronchial tree is low. Cases of intranasal magnets or alkaline button batteries, which may cause electrical or chemical burns and tissue necrosis, are exceptions and could cause more serious complications.

Clinical Features

Most patients seek medical attention within 24 hours. Presentation delays are directly associated with secondary complications, such as infection.

Patients seen in the ED with nasal foreign bodies usually have one of two histories. More commonly, the patient admits to having, or was seen placing, an intranasal object. The less common history is one of purulent or bloody discharge (usually unilaterally) suggestive of an unreported foreign object. Unresolving rhinitis or sinusitis despite appropriate antibiotic therapy should raise suspicion for a nasal foreign body.

Preparing the patient for examination and subsequent removal attempts is advised. Because of the risks of iatrogenic movement of the foreign body further posteriorly, children may need to be restrained to permit the examination. The nasal mucosa is normally quite sensitive, and this sensitivity is increased by any infection or irritation. Examination is facilitated by the application of topical anesthesia and vasoconstrictors to the nasal mucosa. Examination should include both nares, with adequate lighting and visualization facilitated by the use of a nasal speculum. The presence of the foreign body and any secondary tissue damage should be documented. Necrosis of the nasal mucosa and septum may accompany button battery impaction.