Delayed Diagnosis and Treatment of Glaucoma

Digest, Spring 1997

ALLEGATION

Delayed diagnosis and mismanagement of glaucoma resulting in vision loss in one eye.

DISPOSITION

Claim settled on behalf of insured ophthalmologist.

Case Summary

In July 1990, a 47-year-old female CEO for a regional manufacturing company presented to the office of the insured with complaints of blurred vision and light sensitivity in her right eye over the course of approximately two months. A full eye exam was conducted and all findings were essentially normal. The ophthalmologist diagnosed refractive error in both eyes and successfully corrected the patient’s vision to 20/25 OD and 20/20 OS. The patient was instructed to return in two years unless she experienced a further problem.

A month later, the patient returned with complaints that her right eye had worsened, including light sensitivity and a spot of decreased vision. The Amsler grid test showed a defect in the inferior portion of the visual field of the right eye. The ophthalmologist diagnosed conjunctivitis and corneal abrasion and placed the patient on Vasocidin drops for 10 days. The patient returned after four days, again complaining of blurred vision and irritation from the antibiotic drops. The best corrected vision in her right eye was 20/30-2 and in her left eye 20/20-1. Both funduscopic exams were normal. The antibiotic was changed to Gentacidin and the patient was told to return in a week.

The insured did not hear from the patient again for eight months when she appeared with complaints of blurred vision and light sensitivity in the right eye. Visual acuity with correction was 20/30-2 in the right eye and 20/20 in the left. Tension was 30 in the right eye and 28 in the left. Funduscopic exam revealed abnormal cup to disc ratios in both eyes with the worst being 0.8 in the right eye. Visual fields were abnormal on the right and borderline on the left. A diagnosis of bilateral glaucoma was made and the patient was placed on Betagan and instructed to return in 10 days. When the patient returned in 10 days, she reported that the right eye felt better, although visual acuity was essentially the same. Pressure in the left eye had dropped from 28 to 23 but had risen from 30 to 31 in the right eye. The insured placed the patient on a combination of glaucoma medications, which effectively lowered the intraocular pressure to 19 in the right eye.

For the next several months, the patient’s intraocular pressure vacillated from the mid-20s up to 30. The insured noted that intraocular pressure was elevated at some visits because the patient had forgotten to take the glaucoma drops in the morning, resulting in an elevated pressure when the exam took place in the afternoon. The patient also reportedly failed to have her prescription for eye drops filled for a period of three months. Even though the insured continued to monitor the patient’s pressures and adjust her medication every four to six months, this roller coaster pattern of elevated pressures continued throughout most of the next two years.

In September 1993, the patient presented with decreased vision and a change in the appearance of the optic nerve. The cup to disc ratio had now increased to .89 and VA in the right eye was hand motion only. At this point, the insured referred the patient for surgical evaluation and the patient ultimately underwent a laser trabeculoplasty for advanced loss of vision in the right eye. Vision was stabilized but not recovered. The patient sued the ophthalmologist, alleging that vision loss in her right eye was due to delayed diagnosis and mismanagement of glaucoma. The case was subsequently settled before trial.

Analysis

There were two deficits in record keeping that hampered defense of this case. The first was the failure to document ocular pressures on the patient’s second and third visits. Defense experts pointed out that when the patient presented with consistent symptoms of decreasing vision and light sensitivity in the right eye, failure to check pressures would be considered by most to be below the standard. If the pressures were normal and documented, there would be no question regarding the insured’s approach to treatment; however with no pressures recorded, it was left open for the plaintiff to point out that the glaucoma might have been diagnosed earlier. Although the insured stated that his customary routine would have been to check the pressures and that this patient’s must have been normal, there is no mention of this in the chart.

The second record keeping problem was the lack of documentation of patient noncompliance. Over the two years of reported noncompliance, there were very few notations indicating these problems in the medical record. This became critical when the plaintiff attorney interpreted the medical record as showing that the pressures were “just not monitored well” and “adjustments were not timely made” in the medications. The patient testified that she was a model patient who followed all directions. It was very difficult to argue at that point that the variations in treatment patterns were due primarily to patient noncompliance.

Risk Management Principles and Commentary

In recent years, glaucoma cases have developed a significant presence in medical malpractice litigation. A 1996 study of 383 ophthalmology claims from the Medical Liability Mutual Insurance Company of New York found that 15% of the high loss cases (over $250,000) involved the management of glaucoma. The most common problems to appear in litigation were related to failure to diagnose and/or manage chronic glaucoma.¹ An earlier study in 1994 specifically analyzed 194 glaucoma claims from the Physician Insurers Association of America (PIAA) and found that four types of problems account for the majority of allegations in glaucoma claims:²

• Diagnostic error (21.7%)
• Improper performance of care (19.1%)
• Medication error (9.8%)
• Failure to monitor patient (8.2%)

Not every case involving these allegations is a case of negligence. In many instances, the injury to the patient is the result of a known complication that can be defended provided the legal facts of the case are not complicated by poor record keeping. When a plaintiff attorney searches the medical records for the cause of vision loss in a glaucoma patient, inevitably the search will analyze evidence of (1) a failure or delay in diagnosis and (2) a delayed or improper treatment pattern. Documentation or lack thereof in the medical record can make or break a case for either side.

Notes

1. Kraushar MF, Robb JH. Ophthalmic Malpractice Lawsuits with Large Monetary Awards. Archives of Ophthalmology. March 1996; 114: 333-337.
2. Craven RE. Risk Management Issues in Glaucoma Diagnosis and Treatment. Ophthalmic Risk Management Digest. Summer 1994: 3-5.

Risks and Benefits of Writing Off a Patient’s Bill

By Ryan Bucsi, OMIC Senior Litigation Analyst

ALLEGATION

Performance of unnecessary cataract surgery and failure to diagnose and treat glaucoma.

DISPOSITION

Case dismissed by plaintiff just prior to trial.

Case Summary

An OMIC insured performed uncom- plicated cataract surgeries one week apart. Following surgery, the patient had uncorrected visual acuities of 20/25+2 OD and 20/25 OS, with increased intraocular pressures of 27 and 28. The insured prescribed Ocuflox in the left eye and Lotemax in both eyes. During subsequent visits, the patient complained of a foreign body sensation, tired- ness, and irritation in both eyes; a throbbing pain and seeing a yellow ring behind the left eye; and glare and light sensitivity. Suspecting migraines, the insured advised the patient to have an MRI, which was normal.

The patient did not return to the insured’s office for three months, against the insured’s advice, but did seek treatment from another ophthalmologist, who documented 20/20 vision without correction bilaterally and diagnosed a posterior vitreous detachment in the right eye. The patient eventually re- turned to the insured complaining of dry eyes, sharp pain, light sensitivity, and headaches. The insured’s impression was a neuralgic pain problem, and he referred the patient to a corneal specialist. The corneal specialist could not find a treatable diagnosis based upon his examinations. A third ophthalmologist treated the patient with punctal plugs and diagnosed chronic open angle glaucoma.

Analysis

The patient did not allege any malpractice against the OMIC insured until a dispute arose over payment of the cataract surgeries. The patient then claimed that she had been informed by the insured’s staff that her health insurance plan would cover all costs of the surgeries; post surgery, however, she learned that only 70% of the costs would be covered. The insured and his staff disputed the patient’s claim but agreed to write off 10% of the costs, leaving the patient responsible for paying 20%. The patient refused to pay and when the insured pursued these costs through litigation, the patient filed a counter suit alleging medical malpractice. Specifically, she alleged that the OMIC insured performed unnecessary cataract surgery on the left eye and failed to diagnose and treat glaucoma.

OMIC retained an attorney on behalf of the insured and had the case reviewed by both cataract and glaucoma experts. Another expert was retained to opine on whether any of the patient’s other health conditions, fibromyalgia, irritable bowel syndrome, or skin cancer, could have caused her ocular complaints. A summary jury trial was held prior to the actual trial dur- ing which jurors heard an abbreviated version of the defendant’s and plaintiff’s arguments and then issued a mock ruling on the case. The jury ruled 6-0 in favor of the defense. When interviewed by the attorneys, the jurors were so overwhelmingly in favor of the OMIC insured that the plaintiff decided to dismiss the case just prior to the start of the actual trial.

Risk Management Principles

When there is an unanticipated outcome followed by a dispute over billing, OMIC insureds are strongly advised to contact OMIC for advice on how to proceed. OMIC staff can help the insured weigh various op- tions, such as setting up a payment plan, waiving or reducing fees, facilitating a second opinion, and offering the patient additional emotional support. In this situation, the pa- tient faced multiple illnesses and hearing that doctors could find no objective reason for her eye complaints may have been more than she could bear. Rather than address the toll that her condition was taking on her, both she and the surgeon focused on the billing issue, which led to an impasse. OMIC certainly supports a physician’s right to be paid for care provided and works vigorously to defend insureds who meet the standard of care, as we did for this ophthalmologist. Our ultimate goal, however, is to avoid litigation entirely because this is gener- ally in the best interests of all parties. Lawsuits are time consuming and stressful and take time away from one’s practice. Some insureds decide fairly readily to waive their fees when it seems a prudent strategy to avoid litigation. Some do so as a compassionate gesture to the patient or to engender or sustain good will in their community. Whatever decision the insured ultimately makes, OMIC wants it to be a well-informed one.

Reduce the Risks of Mapping the Visual Field

By Ralph Z. Levene, MD

Argus, May, 1993

Next to acuity, the visual field is the most important determinant of visual function. Mapping the field has become increasingly complex during the past decade. The variety of instruments, methods and strategies to choose from, as well as the sea of numbers, can be overwhelming. Confusion over which instrument to buy and how to set up a visual field protocol may be eased by talking to an expert.

Even before technology offered so many choices, visual fields often were the source of many malpractice suits. Faulty technique, misinterpretation of results, failure to test or to follow up on tests often were to blame. The following risk management considerations can help you avoid these and other liability problems related to visual field testing.

First, ask yourself how your office performs in technique and interpretation. Do you or your technician need a refresher course? Are fields interpreted shortly after they are done? Are all interpreted fields filed together in the correct chart? An unread or misplaced field is not a legal defense.

What is your protocol on routine screening? Some ophthalmologists perform a screening on all new patients and periodically on regular patients, following up with a definitive field if the screening is suspicious. Others prefer to perform a definitive test when there are suspicious clinical circumstances. Both strategies can be legally and ethically correct.

However, delaying or failing to follow up on suspicious or puzzling clinical circumstances is a frequent factor in malpractice suits involving visual fields. In a case from the OMIC files, a physician notes a suspicious pale optic disc and an acuity of 20/20, but misses a pituitary tumor. He schedules the patient for a return visit in one year by which time the tumor has become inoperable.

In another case, a physician notes a suspicious cupped optic disc, visual acuity of 20/20, and pressures of 16. He schedules the patient for a return visit in six months. The patient fails to keep the appointment and the physician does not follow up. When the patient finally returns two years later with frank glaucomatous disc and visual field changes, the diagnosis of low tension glaucoma has been significantly delayed.

Does the defect fit the diagnosis? An ophthalmologist takes over the care of a patient being treated with a topical beta-blocker for glaucoma. Many of the patient’s visual fields have a vertical midline defect and pressures of 10 to 12. Relying on the previous diagnosis of glaucoma, the ophthalmologist misses a brain tumor.

Do you recognize artifacts and evaluate the reliability of each field? Some patients never yield a reliable field and others do so intermittently. The newer static methods are more sensitive to detecting defects but probably are more prone to artifacts. When in doubt or in unusual circumstances, repeat the field.

Is the defect progressive? This is a critical point in patient management. Apart from artifact, variations from test to test often are underestimated with consequent errors in interpretation. Case in point: an ophthalmologist has been treating a patient with an advanced case of glaucoma and a stable field defect. On a recent visit, a visual field, performed with reasonable reliability, shows an apparent change and is incorrectly interpreted as a significant progression. The ophthalmologist suggests surgery. The patient seeks a second opinion. A repeat field shows a previous stable defect. Unnecessary surgery, with the potential for a lawsuit, is avoided. The change interpreted by the first ophthalmologist as significant was actually a normal variation from one test to another.

Another factor to consider when evaluating results is whether there has been a change in technique. Switching from tangent or Goldman instruments to newer computer assisted methods can skew results. Discuss ambiguous results with an expert or refer the patient for a second opinion. Don’t be afraid to ask for help.

Risk Management Issues in Glaucoma Diagnosis and Treatment

By E. Randy Craven, MD

Digest, Summer, 1994
Glaucoma-related claims and lawsuits arise relatively infrequently. When they do, however, they are more likely to result in indemnity payments, and those payments are likely to be substantially larger than they are for other types of ophthalmic claims.

Using data collected by the Physician Insurers Association of America (PIAA), whose member companies collectively insure more than 100,000 physicians nationwide, this article will explore the nature of glaucoma-related claims and offer guidelines to avoid or minimize the risks associated with these claims. PIAA has collected data on more than 109,000 medical claims and lawsuits in all specialties since January 1, 1985, making its database the most detailed and comprehensive source of medical malpractice loss data currently available.

By comparison, there are only seven claims arising from treatment of glaucoma patients in OMIC’s claims database. While glaucoma cases represent only 1.5% of all OMIC claims, they account for 6% of the ophthalmic claims in PIAA’s database and 7.8% of the 700 medicolegal cases in ophthalmology reviewed by Jerome W. Bettman, Sr., M.D. (Ophthalmology 1990;97:1379-84). The small percentage of OMIC glaucoma claims is probably a reflection of OMIC’s limited claims experience over a relatively short period of time. Therefore, for purposes of analyzing frequency and severity of glaucoma-related claims, the PIAA database is a more comprehensive and reliable source of statistical information.

Claims Frequency and Severity

Figure I compares claims frequency (number) and severity (indemnity payments) of all medical claims in the PIAA database as of December 31, 1993, with all ophthalmology-related claims, all cataract claims, and all glaucoma claims. As Figure I indicates, half of all glaucoma-related claims result in an indemnity payment, and these payments are almost 20% higher than the average ophthalmology indemnity payment. As the chart also shows, although cataract patients file a third of all claims against ophthalmologists, these claims usually settle without an indemnity payment or with a relatively low payment. To date, OMIC has not paid an indemnity to a claimant or plaintiff in any of its glaucoma-related claims. OMIC’s indemnity rate for all types of claims is 24%.

Analysis of Glaucoma-Related Misadventures

At OMIC’s request, PIAA analyzed 194 claims with a diagnosis of glaucoma to determine the nature of allegations (“medical misadventures” alleged) and, if present, associated issues (e.g., informed consent) which prompted or complicated these claims. OMIC also requested that surgical procedures be sorted from medical procedures to ascertain if one area held greater risk.

Figure II lists the types and percentages of “medical misadventures” (a principal departure from accepted practice) alleged in glaucoma claims. Four types of misadventures account for the majority of allegations: diagnostic error (21.7%), improper performance of care (19.1%), medication error (9.8%), and failure to supervise or monitor the case (8.2%).

The most frequent and second most expensive misadventure is a diagnostic error. The most expensive is failure to refer.

Patients and juries take serious issue to vision loss. When claims arise related to diagnostic errors or failure to refer, it may be difficult to explain to a jury how this frequent cause of blindness was not recognized or suspected by the defendant ophthalmologist. Experts will tell the jury that loss of vision from glaucoma may be prevented through early diagnosis and therapy. It is easy, therefore, for the plaintiff’s attorney to show the relation between the breach of duty (diagnostic error) and the cause of damages (blindness or vision loss).

With glaucoma, claims arising from medical treatment outnumber surgery-related claims by more than 50%, and they are more likely to result in an indemnity payment (54% vs. 44%). The average indemnity paid, however, is about the same for medical and surgical procedures, $142,000. (See Figure III.)

Associated Issues in Glaucoma Claims

A major finding in this review was that claims of abandonment by glaucoma patients result in sizeable indemnity payments. Although abandonment was alleged in only slightly more than 1% of all cases, it accounted for the largest average indemnity payment among claims with an associated issue. It is especially important not to let glaucoma patients “slip through the cracks” and out of the practice. If a “glaucoma suspect” becomes noncompliant, difficult to treat or follow, misses appointments, or does not take prescribed medications, the ophthalmologist may be exposed later to claims of abandonment. This risk may be reduced by proper documentation of the missed visits. A jury will want to know what steps were taken to deal with the patient’s noncompliance. Careful documentation in these cases can make the difference between paying nothing and paying half a million dollars.

Detection of glaucoma entails a complete eye examination, including measurement of intraocular pressures, gonioscopy, evaluation of the optic nerve, and visual field testing. Results of these examinations should be recorded in the patient’s chart each time they are performed. Glaucoma suspects should be flagged for more frequent examinations to monitor for changes and informed of the factors that put them at risk for developing glaucoma. They should be told that failure to comply with treatment can result in vision loss. If educational brochures are offered to glaucoma patients, it should be documented in the chart that they received them.

Standardize Record Keeping

The following suggestions may help standardize glaucoma record keeping and management once a patient is diagnosed. First, as previously mentioned, it is important to have a standard way of initially evaluating the patient to establish adequate baseline information. After a complete eye exam, the thought process should shift to the type and stage of the glaucoma.

Once the diagnosis is established, it is necessary to monitor the patient’s progress. This can be done with sequential evaluations of previous office records, but an abbreviated sheet with the glaucoma-pertinent information is also reasonable. In my practice we use a one-page “flow chart” to indicate the date, medications, vision, IOP, gonioscopic findings, optic nerve configuration, and static visual field statistical parameters for each visit. Ten or more visits can be recorded on a single sheet, making it easy to detect changes. (A copy of this flow chart may be obtained by contacting OMIC’s risk management department). The remainder of the examination is documented on the standard SOAP progress record.

Sort Visual Fields Separately for Each Eye

Visual fields should be sorted separately for the right and left eye in reverse chronological order. This allows for a quick comparison of the two eyes, checking for a neurologic defect as well as a progression in an individual eye. A system for documenting the optic nerve shape is necessary to initially stage the level of the glaucoma and to check for progression of the disease.

The type of equipment used for following glaucoma is an important consideration. Mostglaucoma specialists use static perimetry for their initial evaluation and for following the course of the disease. Goldmann perimetry can be helpful for advanced cases. Most ophthalmologists use an estimate of the optic nerve head anatomy based on a drawing or ratio estimate. Some ophthalmologists use photographs to help follow up on cup progression. Newer computerized nerve head analyzers may be helpful but have not yet been accepted as a modality for detecting changes in the nerve.

Establish Treatment Goals

Establishing initial and subsequent treatment goals can be difficult in glaucoma cases. Experience is invaluable in estimating a treatment intraocular pressure goal. If progression occurs, the treatment goal should be reevaluated. If surgery is an option, the patient mustclearly understand the purpose of the surgery and the outcome that can reasonably be expected. Many patients undergo surgery expecting it to improve their vision; this may not be the case with glaucoma surgery.

Physician-patient rapport requires keeping the patient apprised of the stage of the disease, its course to date, and what can be expected in the future. This type of dialogue with the patient helps reduce an ophthalmologist’s risk since a key trigger in lawsuits is the surprised patient who feels betrayed because he or she finds out more might have been done. Obviously, some cases will progress despite treatment, and this possibility needs to be reinforced with glaucoma patients and carefully documented in their chart.

they are prescribed so the patient will be able to recognize potential problems before they become serious. Patient information sheets on the side effects of specific anti-glaucoma medications are available from the American Academy of Ophthalmology and the American Medical Association.

Risk Management Suggestions

In summary, the data collected by all doctor-owned insurance carriers show that glaucoma-related claims result in an indemnity payment more than 50% of the time. By adhering to the following risk management guidelines, ophthalmologists may avoid becoming another casualty of this statistic:

• Begin with a complete diagnostic eye exam.
• Develop a system for glaucoma record keeping and management. Keys to this system include using up-to-date equipment and following a standard method for initially and subsequently evaluating glaucoma patients.
• Once a patient is diagnosed with glaucoma, establish a specific goal for treatment and use accepted parameters to follow the course of the disease.
• Keep glaucoma patients apprised of the progress of their disease. Inform them of the risks and benefits of their treatment, including drug side effects, and document that you did so.

Figure I – Claims Frequency and Severity

	Total Claims	Closed Claims	Closed with Indemnity	Average Indemnity
All Specialties	109,427	95,474	32%	$135,980
Ophthalmology Claims	3,264	2,840	30%	$116,138
Glaucoma Claims	194	169	50%	$142,088
Cataract Claims	985	881	26%	$85,708

Figure II – Glaucoma Claims by Medical Misadventure

Figure III – Surgical vs. Medical Procedures

	Total Claims	Closed Claims	Closed with Indemnity	Average Indemnity
All Glaucoma Claims	194*	169	50%	$142,088
Medical Procedures	132	122	54%	$142,076
Surgical Procedures	58	43	44%	$142,148

^* 4 cases indicated no procedure performed

Risk of Using — and Not Using — Antimetabolites in Glaucoma Surgery

By B. Thomas Hutchinson, MD, and E. Randy Craven, MD

Argus, September, 1996

Although the general medical and disease-specific risk factors for glaucoma surgery are well known and discussed as part of the informed consent process, many ophthalmologists do not commonly address the use of operative and postoperative antimetabolites. Their use can mean the difference between success and failure in glaucoma filtration surgery. The surgeon who fails to discuss with the patient the rationale behind the decision faces potential liability if the patient is unhappy with the outcome.

Even when used appropriately, these agents may cause serious postoperative complications and introduce significant risks for the future. Although no definitive criteria have been established for their use in glaucoma filtration surgery, a consensus is evolving as to when they are most valuable.

Mitomycin-C and 5-Fluorouracil, the most commonly used antimetabolites, may significantly benefit eyes expected to have an excessive fibroproliferative response. Examples include previously operated eyes, failure of previous filters in the same or other eye, coexisting uveitis or rubeosis, combined glaucoma and cataract surgery, and risk factors related to the patient’s age and race.

Since most glaucomacologists do not use these agents routinely in every case, it is equally important to tell the patient why they might not be used, for example, in eyes with no unusual risk factors for failure. The ophthalmologist might elect not to use Mitomycin-C in patients who are at added risk for antimetabolites such as the moderate to highly myopic eye, patients with hypotony after previous surgery (with or without antimetabolites), and patients with potentially complicating corneal, retinal or wound healing problems. In today’s medicolegal practice arena, it is perhaps as important to discuss use and nonuse of these modalities as it is to discuss the rationale for and against the surgery itself.

In addition to the usual complications of glaucoma surgery, it is not uncommon for the “antimetabolite bleb,” especially with Mitomycin-C, to provide overfiltration, initially associated with hypotony and often retinal edema. The use of Mytomycin-C may place the eye at additional future risk of late bleb leak and necrosis of avascular tissue as well as a higher incidence of late bleb infection and endophthalmitis. The hypotony and retinal edema now recognized as a more frequent occurrence with antimetabolites do not commonly respond to medical or surgical attempts at correction. Potential complications of using antimetabolites should be discussed with the patient, along with the risk of failure for glaucoma control without using these new modalities.

It is crucial that the patient understand not only the spectrum of glaucoma as a potentially blinding disease but also the likelihood of success with all modalities of treatment consistent with the patient’s particular disease. In making a decision about surgery, there must be ample opportunity to educate and include the patient in the decision-making process about the concept of surgery as well as adjunctive treatments that may be appropriate for a particular patient. Educating the patient about your rationale for deciding whether to use these new and often valuable antimetabolite medications will clearly identify you as the patient’s advocate and reduce the likelihood that you will become adversaries in the future.

OMIC provides model patient information sheets regarding the use of Mitomycin-C and 5-Fluorouracil during glaucoma surgery, which you can give to patients prior to surgery. Fax your request for these documents to the OMIC Risk Management Department, 415 771-1095.