A Clinical Risk Case Study – Failure to Diagnose and Treat Acute Angle Closure Attack leading on to develop Acute Glaucoma

Article co-written by TMLEP Clinical Risk and Patient Safety Publishing Group and Mr Datta MBBS MS (Ophthal) FRCSEd FRCOphth, Consultant Ophthalmologist and Ophthalmic Surgeon.

The Scene

A 65-year-old woman brought a claim against her Consultant Ophthalmologist for a failure to diagnose and treat acute angle closure attack appropriately, which resulted in progression of the condition to glaucoma that consequently lead to loss of vision in the left eye.

The patient was referred to an Ophthalmologist by her GP due to bad headaches and intermittent loss of sight in her left eye. The patient attended the eye clinic where upon review, history of multiple subacute angle closure attacks were not recognised.

In clinical assessment, the Ophthalmologist did not carry out appropriate examinations on the patient such as; not doing a gonioscopy, through a slit lamp examination of the anterior (front) compartment of the eye, which resulted in missing an obvious shallow anterior chamber (front). The Ophthalmologist then made the decision to dilate the pupils and sent the patient home, suggesting she should be seen by a neurologist to exclude other causes.

Later the same evening the patient attended A & E after experiencing pain, nausea, vomiting and reduced vision in the left eye. A CT scan of her head showed no abnormality and was later transferred to a stroke ward considering a stroke or migraine was the most probable diagnosis. The patient’s eye wasn’t examined despite complaining of eye pain and headache. Despite a recognition of unresponsive pupils in both eyes and along with persistent symptoms, the patient wasn’t seen by an Ophthalmologist for a further 3 days, when she was diagnosed with acute glaucoma.

The prolonged nature of the attack resulted in the condition converting from a reversible to irreversible blindness and the patient sustained a reduction of more than 50% of her vision and is registered partially sighted.

Our Independent Clinical Findings

TMLEP’s independent review identified a number of failures in the standard of care provided, notably the clinician:

  • Failed to take or record appropriate history - hence missed noting down intermittent visual loss, suggestive of subacute angle closure attacks.

  • Failed to do a complete ocular examination - did not do gonioscopy - which helps to identify eyes that are at risk of developing acute angle closure attacks.

  • The above two errors resulted in the inability to identify that the Claimant was at risk of developing acute angle closure attack.

  • The Claimant was subsequently dilated in the eye clinic and sent home. The dilating drops used in eye clinic precipitated an acute angle closure attack (sudden raised eye pressure) in both the eyes later in the day, which necessitated hospital admission.

  • Hence, the Claimant's problem was caused by the examining ophthalmologists' failure to properly examine the patient and assess the risk factors and putting in dilating drops without due care.

Once the patient was subsequently admitted to Accident and Emergency, our independent review found further substandard care.

On assessment, it was clearly noted that both pupils were unresponsive. This observation, along with the fact that both eyes were red and the Claimant was unable to open her eyes with associated symptoms of decreased vision, headache, nausea, and vomiting, should have triggered an urgent ophthalmology review. Unfortunately, this did not happen and therefore there was a failure to consider an ophthalmology diagnosis in this case.

The Claimant's current symptoms takes precedence over whether the patient had prior ophthalmology review or not in deciding a second ophthalmology opinion.

How to prevent recurrence and improve patient safety

When a patient with worrying presenting symptoms presents to the eye casualty, the following should have happened:

  1. An appropriate history should have been undertaken; had this been done, this would have identified that the Claimant's symptoms are suggestive of subacute angle closure attacks, due to a history of intermittent blurred vision.
  2. A thorough ocular examination, including gonioscopy, would have identified that the Claimant had a shallow anterior compartment of the eyes and was at risk of developing acute angle closure attack.
  3. This, in turn, would have triggered arranging a preventive Laser peripheral iridotomy (LPI) - making a hole in the coloured part of the eye - to prevent the development of acute angle closure attack.
  4. Keeping in mind the above findings, the Claimant's pupil would not have been dilated prior to LPI.
  5. Following a successful LPI, the Claimant's chance of developing acute angle closure attack would have been remote and prevented a visual loss.

To Conclude

Our independent review finds that there are two counts of substandard care:

  1. The inability of the ophthalmologist to identify that the Claimant was at high risk of developing acute angle closure attack. This resulted in unwittingly dilating both of the Claimant's eyes and precipitating an acute angle closure attack - this was completely avoidable.

  1. Failure of the Accident and Emergency medical team to identify an acute angle closure attack, thus prolonging the duration of this condition which resulted in irreversible damage to the optic nerve (resulting in glaucoma), which is the reason for that patient’s visual loss and being registered partially sighted.

Important Notice: This article is intended to raise awareness to clinical risk issues in an effort to reduce incidence recurrence and improve patient safety. This is not intended to be relied upon as advice. Facts have been altered to ensure this case is non-identifiable, albeit clinical learning points remain applicable. To request an independent clinical review, please contact admin@tmlep.com or call +44 (0)203 355 9796.

TMLEP Clinical Risk and Patient Safety Publishing Group and Mr Datta MBBS MS (Ophthal) FRCSEd FRCOphth, Consultant Ophthalmologist and Ophthalmic Surgeon. (2017). A Clinical Risk Case Study – Failure to Diagnose and Treat Acute Angle Closure Attack leading on to develop Acute Glaucoma. TMLEP Clinical Risk Case Studies. 1 (2), 1.