Ординатура / Офтальмология / Английские материалы / Risk Prevention in Ophthalmology_Kraushar_2008

secondary cataract, removal of the foreign body, repair of retinal defect or detachment, and corneal transplant are common. The risk of infection, although possible, is surprisingly small but must not be disregarded. Retention of some foreign material may cause long-term toxicity and loss of vision.

One legal case involved a man who was striking metal with metal and felt something fly into his left eye. He was seen by an emergency room physician who diagnosed a corneal tear with a misshapen pupil. An ophthalmologist came to see the patient in the emergency room and subsequently saw the patient in his office. Because the corneal laceration was self-sealing, it was not sutured until 10 days later. At this time, the traumatic cataract was removed and a posterior chamber intraocular lens inserted. No attempt was made to discover an intraocular foreign body. The patient’s vision in his left eye returned to 20/20. Eight months later, the vision in the patient’s left eye decreased to 20/40 and heterochromia iridis was noted. Still no examinations were performed to ascertain the presence of an intraocular foreign body. Approximately 13 months after the injury, the patient was legally blind with respect to both central vision and visual field. There was a marked decrease in the electroretinogram in the affected eye. A consultant confirmed the presence of an intraocular foreign body and the diagnosis of siderosis bulbi.

Endophthalmitis

Exogenous endophthalmitis is most common as a complication of cataract surgery. However, it may be seen following any perforating trauma or intraocular surgery, including vitrectomy. The rate and degree of damage depends on the pathogenicity and virulence of the organism. If any suspicion of endophthalmitis exists, diagnosis and treatment are urgent. Not every case has a classic appearance, and pain is not always present. Anterior chamber and vitreous taps with Gram stain and intraocular fluid sent for culture and sensitivity should be requested. Unless the patient’s vision is reduced to the perception of light, intravitreal antibiotics are the treatment of choice.12

Orbital Disease

The orbit may be affected by numerous conditions, some of which require prompt diagnosis and attention. The possibility of more serious disease will vary according to history and findings on examination.

Orbital Cellulitis

The symptoms and signs of painful proptosis, lid and conjunctival edema with ophthalmoplegia along with fever and general malaise should raise

suspicion of orbital cellulitis.13 Because immunodeficiency is increasingly common, one must entertain the possibility of mucormycosis.14 Other syndromes or diseases that must be considered with various combinations of pain, proptosis, signs of congestion, vision loss, and defect in function of cranial nerves III, IV, V, and VI include the superior orbital fissure syndrome, Tolosa-Hunt syndrome, cavernous sinus thrombosis, orbital apex syndrome, and carotid-cavernous sinus fistula.15 If not expeditiously diagnosed and treated, some cases of cavernous sinus thrombosis and carotidcavernous sinus fistula can be fatal.

Orbital Hemorrhage

Any cause of severe orbital hemorrhage may secondarily create an elevated intraocular pressure or pressure on the optic nerve, creating ischemia.

Orbital Fractures

In cases of severe and often blunt trauma, an orbital fracture with compression of the optic nerve is possible. Orbital floor fracture with entrapment of a rectus muscle may not only cause an immediate impairment of extraocular movement (EOM) but also cause a persistent impairment of extraocular movements if there is permanent damage to the muscle.16

Patients manifesting orbital disease, especially those with systemic symptoms and signs, frequently require consultation with an appropriate subspecialist. Some of the differentiating aspects among these diseases are quite subtle, and, unless an ophthalmologist is thoroughly familiar with these diseases, serious errors may occur. Most ophthalmologists are not going to undertake treatment of complicated systemic diseases.

Cranial Nerve Palsies

Cranial nerve palsies may appear as isolated phenomena. They are seldom emergent, but aneurysmal cranial III nerve palsy, usually with a dilated pupil, requires a prompt consultation with a neurosurgeon. This is especially the case in younger patients 20 to 50 years old without a high risk factor for vascular disease such as diabetes mellitus or hypertension.17,18

Although rupture of an aneurysm is uncommon, the possibility should not be disregarded. An on-call resident saw a patient with a cranial III nerve palsy. He was unfamiliar with the possible etiologies, performed a visual field examination, and sent the patient home. During the night, the aneurysm ruptured and the patient died.

Flashes of Light and Floaters

Ophthalmologically, the symptoms of flashes of light and floaters are most frequently associated with posterior vitreous detachment. At the time of posterior vitreous detachment, a retinal tear may occur. Prophylactic treatment of retinal breaks remains controversial. If a patient experiences such symptoms and is told by an ophthalmologist there is no evidence of ocular disease and later develops a retinal detachment, the possibility of a lawsuit is frequently explored.19

Rhegmatogenous Retinal Detachment

Rhegmatogenous retinal detachment is not an ophthalmological emergency. However, most cases are surgically operated with 24 to 48 hours of diagnosis. More expeditious surgery is scheduled if the macula has not detached. Following successful surgery and especially if the macula was detached, the restoration of vision is often disappointing to the patient. Lawsuits are often explored because of allegations of delay in diagnosis and treatment.20

Angle Closure and Other Glaucomas

If angle closure glaucoma is not diagnosed and the intraocular pressure is sufficiently high, permanent visual impairment as severe as blindness may occur.21 Other types of secondary glaucoma with acute or dangerously elevated intraocular pressure may cause similar damage. Hyphema, especially in patients with sickle cell disease, may elevate the intraocular pressure to threatening levels.22

Corneal Ulcer, Descemetocele, or Perforation

A corneal ulcer with a descemetocele or perforation requires urgent surgical therapy.23

Iridocyclitis

Iridocyclitis (iritis) or anterior uveitis is commonly misdiagnosed, especially when a patient is not examined with a slit lamp. Adverse sequelae of incorrect diagnosis rarely cause serious damage. The formation of posterior synechiae for 360° creating iris bombe with elevated intraocular pressure is an exception.

Additional complications associated with iridocyclitis are peripheral anterior synechiae, hypotony, cystoid macular edema, and disc edema. Other manifestations usually from chronic disease are cataract, cyclitic membrane, and band keratopathy.24

Problems with Immunocompromised Patients

Although not limited to immunocompromised patients, causes of acute loss of vision requiring prompt evaluation include endogenous endophthalmitis, necrotizing retinitis caused by cytomegalovirus, toxoplasmosis, or herpes viruses, and syphilitic chorioretinitis.25

Conclusion

The optimum clinical evaluation and treatment of many diseases is often controversial, and no method guarantees success. Controversy is legitimate if there is more than one acceptable approach to a problem. Damages must be created by a deviation from an acceptable standard of medical care expected from a reasonably well-qualified physician encountering a situation with identical or similar circumstances. Occasionally unjustified malpractice litigation will occur. The best protection is to consider the benefit of the patient as primary. One of the pillars of the practice of medicine is to allay a patient’s fears, which often requires some self-sacrifice and inconvenience on the part of the physician. Meticulous and complete documentation is mandatory. If any uncertainty in diagnosis and treatment remains, consultation with another physician is very advisable. Proper communication with the patient and involved medical personnel is most important.

When a patient is seen with an emergent or urgent situation, no abbreviation of important aspects of the examination should occur. The brief examples of litigation cited are not singular or unique but are recurrent themes in cases submitted by attorneys for review to potential expert medical witnesses.

References

1.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:55–77.

2.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:163–171.

3.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:335–338.

4.Purvin V, Kawasaki A. Neuro-Ophthalmic Emergencies for the Neurologist. Neurologist 2005;11(4):204–205.

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5.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:83, 356–358.

6.Purvin V, Kawasaki A. Neuro-Ophthalmic Emergencies for the Neurologist. Neurologist 2005;11(4):200–202.

7.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:358–360.

8.Purvin V, Kawasaki A. Neuro-Ophthalmic Emergencies for the Neurologist. Neurologist 2005;11(4):198–200.

9.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: Lippincott-Raven; 1998:84-85, 97–106.

10.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:81-82, 207–226.

11.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:83-84, 309–318.

12.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:82, 275–283.

13.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:85, 131–132.

14.Purvin V, Kawasaki A. Neuro-Ophthalmic Emergencies for the Neurologist. Neurologist 2005;11(4):214–215.

15.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:387–391.

16.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:85, 107–116.

17.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:369–372.

18.Purvin V, Kawasaki A. Neuro-Ophthalmic Emergencies for the Neurologist. Neurologist 2005;11(4):217–222.

19.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:347–348.

20.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:87, 285–307.

21.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:235–255.

22.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:231–234.

23.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:83, 194–198.

24.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:138.

25.MacCumber MW, ed. Management of Ocular Injuries and Emergencies. Philadelphia: LippincottRaven; 1998:144–150.

discomfort when applied. Laser trabeculoplasty has also been useful as the next step in treatment, often making it possible to avoid aqueous drainage surgery such as trabeculectomy, which was formerly the next step in cases of inadequate pressure control. Of all the alternatives, the use of topical agents is currently considered the first line of glaucoma treatment and is indicated for most patients. Despite the advantages, however, a number of patients will still find it difficult to take their medicines on schedule and in the manner prescribed. This lack of compliance will eventually result in the typical glaucomatous optic nerve changes accompanied by visual field loss.

Compliance itself is the patient’s willingness and ability to adhere to the treatment plan established by the ophthalmologist and is based on factors specific to the individual patient. A lack of compliance is usually occasioned by a change in the patient’s mental or physical status or a lifestyle change. This type of noncompliance is not willful and not the result of failure of the interpersonal exchange between physician and patient. Noncompliance becomes a problem when it leads to damage to the optic nerve and vision loss. To prevent this damage and loss of vision, the ophthalmologist is justified in advancing treatment to the next level whether it be laser or surgical intervention even though medical treatment would still be effective. In such cases the physician is permitted to substitute his or her best judgment and to depart from the usual and customary practice of using topical agents that are still effective. Anyone treating glaucoma must have a continued awareness of the effectiveness of the treatment modalities prescribed. If glaucomatous change progresses and visual damage occurs, the physician must be prepared to alter treatment in order to best accommodate the situation of the patient.5

Risk Factors for Glaucoma

The multicenter studies mentioned at the beginning of this chapter have identified several previously unsuspected risk factors that precede the development of glaucoma and that must be considered when evaluating the patient. Not including this new information into the patient examination can result in liability for any adverse consequences resulting from the oversight. Among both established and recently recognized risk factors are a reduced central corneal thickness, a family history of glaucoma, the amount of increase in intraocular pressure at diagnosis, the presence of high myopia, vascular disorders such as migraine, the patient’s age at diagnosis, African-American heritage, and the amount of increase in cup to optic disc ratio at the time of diagnosis. Furthermore, assuming that intraocular pressures in the “normal” range (10 to 21mm Hg) preclude the possibility of glaucoma developing in a particular patient is unjustified, and even these low pressures may lead to the progression of glaucomatous optic nerve damage and a significant loss of vision.

Individuals with two or more risk factors should be examined at more frequent intervals to identify early the onset of glaucoma, because damage to the optic nerve is cumulative throughout the patient’s life and early diagnosis will reduce later

damage. This concern has become especially important as the nature of normaltension glaucoma has become better understood. This type of glaucoma is the situation in which the intraocular pressures remain within the “normal” range despite obvious and progressive optic nerve damage. Legal doctrine requires the physician to take reasonable precautions in treating the patient and addressing these risk factors for glaucoma has become a legal requirement. Failure to reexamine the suspect patient at appropriate intervals to ensure the early diagnosis of normal-tension glaucoma also violates the physician’s common law duty to the patient.6,7

Consider the following situation. A woman with high myopia was examined periodically by her physician to measure and treat the myopia. Other than occasional attacks of migraine, vertigo due to low blood pressure, and a family history of glaucoma, she was in excellent health with no subjective symptoms. Intraocular pressures were measured at each examination and were always within the “normal” range for these values. As part of his “routine examination” the physician had always examined her undilated fundus using a direct ophthalmoscope. On one occasion the patient was examined by another physician who dilated her pupils, examining her fundus using an indirect ophthalmoscope. Because of the unusual appearance of her optic nerves, he also performed a slit-lamp examination using a 90-diopter lens to better evaluate the discs. The patient was found to have a bilateral optic cup to disc ratio of 0.6 with shallowing of the cup temporally plus glaucoma-specific changes in her peripheral visual fields. The diagnosis of normal-tension glaucoma was made. The patient sued the original physician for her partial loss of peripheral vision because of his failure to do a dilated examination of the optic nerves, especially given her risk factors. Her original physician claimed as a defense that her intraocular pressures were always “normal,” and he had no reason to suspect glaucoma. The court held that her history of migraine and high myopia were risk factors for ocular problems including glaucoma and that a more thorough examination was indicated.

Pediatric Glaucoma

Pediatric glaucoma is not adult glaucoma just as pediatrics is not adult medicine. Failure to remember this can lead to diagnostic and management problems with legal consequences. In the presence of the classic triad for primary congenital glaucoma consisting of epiphora, photophobia, and blepharospasm, the diagnosis will usually be obvious for the ophthalmologist. Enlargement of one or both corneas from the increased intraocular pressure makes the diagnosis easier. When only epiphora or photophobia is the presenting symptom in an infant, a more thorough examination is necessary to establish the diagnosis. This includes a dilated fundus examination, because disc changes can occur more rapidly even at lower pressures in infants. A cup to disc ratio of greater than 0.3 is rare in the normal infant while not at all unusual in congenital glaucoma. Having an index of suspicion followed by an appropriate examination will usually reveal the correct diagnosis, avoiding a failure to diagnose on the part of the ophthalmologist.

Although primary congenital glaucoma is the most common type of infantile glaucoma, the physician must also have an awareness of other physical conditions that may lead to glaucoma. Secondary glaucoma can occur in the child with Marfan’s syndrome, aniridia, Sturge-Weber syndrome, and less commonly in neurofibromatosis. In these conditions and in cases of corneal dysgenesis, the measurement of intraocular pressure plus a dilated fundus examination focused on the disc are necessary to fulfill the physician’s duty to the patient.7

Options in Glaucoma Management

Because of individual differences arising from the patient’s current health status and past medical history, an element of uncertainty exists in any patient’s response to a particular treatment. In the management of glaucoma it sometimes becomes necessary to alter the initial treatment plan if it fails to be effective in protecting the patient’s vision. The changes may include additional or different topical medications, laser trabeculoplasty, or surgical drainage procedures such as trabeculectomy or a tube drainage device.8,9

Consider the following situation. A patient had primary open angle glaucoma with intraocular pressures that were becoming increasingly difficult to control using topical medication alone. Laser trabeculoplasty had not provided sufficient pressure reduction. The surgeon originally planned a trabeculectomy and discussed this in detail with the patient, obtaining proper consent for the procedure. Trabeculectomy is creation of an opening into the globe under a flap of sclera with the flap covered by the bulbar conjunctiva and Tenon’s capsule, thereby providing a relatively controlled exit for the aqueous in the anterior of the eye. During the surgery the surgeon realized the condition of the conjunctiva would not allow for a successful trabeculectomy and decided instead to place a tube drainage device. He informed the patient, under local anesthesia, of his decision during the surgery itself, although the patient later stated he had no recollection of the conversation because of the medicine he had been given. Because the patient afterward complained of discomfort allegedly due to the presence of the drainage device attached to his eye, he sued on the grounds of lack of consent for the change of procedure. In the preoperative discussion the surgeon had raised the possibility of placement of a tube drainage device. Both the patient and the surgeon were aware of the need to control intraocular pressure to preserve vision. Despite this patient’s claim of pain and discomfort from the device, in this instance the surgeon’s experience in identifying conditions that could lead to an unsuccessful outcome was an important component of the surgery itself and was his successful legal defense. Preoperative consultation must include a brief description of possible contingencies to avoid later liability and must include the surgeon’s freedom to select what appears to be the best course during the surgery.