Sir,

Descemet’s membrane detachment (DMD) is an uncommon condition with a wide range of possible aetiologies. Probably the commonest cause is a localised detachment occurring at cataract extraction surgery. More extensive detachments give rise to a ‘double anterior chamber’ after perforation of Descemet’s membrane in deep lamellar keratoplasty.1 Large DMD after cataract extraction is rare. Non-surgical factors that could predispose to DMD are traumatic, congenital glaucoma and corneal ectasias, among others.

DMD detachment can be classified as:

Planar: <1 mm separation from the stroma

  • Peripheral detachment only

  • Combined peripheral and central detachment

Non-planar: >1 mm separation from the stroma

  • Peripheral detachment only

  • Combined peripheral and central detachment.2

Case report

An 80-year-old woman was referred by her General Practitioner with a gradual deterioration of vision in her right eye. She had no past ocular history. She had a medical history of chronic renal failure, hypertension and left ventricular failure. On examination the visual acuity was hand movements unaided in the right and 6/12 in the left. There was a dense nuclear cataract in the right eye and mild nuclear cataract in the left eye. There were no other ocular abnormalities. She was listed for right cataract surgery as a day case.

She underwent uncomplicated right phacoemulsification cataract extraction with intraocular lens implant under local anaesthesia. She had clear corneal incision at the 11 o’clock position using a 2.5 mm disposable keratome and a superonasal paracentesis. Divide and conquer phaco-emulsification was performed using a Millennium Storz machine (STORZ Ophthalmics Inc, St Louis, MO, USA). The phaco-emulsification power and time were 13% and 2 min and 24 s respectively. The viscoelastic (Provisc) used throughout the procedure was completely removed at the end of the procedure. Balanced salt solution (BSS Alcon) was used as the infusion fluid. Corneal incision was sealed with two 10/0 vicryl sutures. Finally the patient had a subconjunctival injection of Cefuroxime 125 mg and Betnesol 2 mg and the eye was covered with a plastic shield.

The patient was reviewed 4 days following surgery. She was asymptomatic. Her right visual acuity was 6/36 unaided, improving to 6/18 with pinhole. There were Descemet’s membrane folds, mild inflammatory reaction in the anterior chamber and the intraocular pressures were 12 mmHg in the right eye and 18 mmHg in the left. She was given guttae Dexamethasone 0.1% to be used four times a day, until the next visit.

She was closely monitored and 7 weeks after surgery, her vision in the right eye had deteriorated to 6/60 unaided, 6/36 with pinhole. The patient was complaining of right epiphora, but the eye was comfortable otherwise. The right corneal sutures had dissolved completely and there were no signs of ocular inflammation. Right intraocular pressure was 16 mmHg. The posterior cornea was noted to have a combined non-planar DMD involving approximately two thirds of the cornea, extending from 5 o’clock around to 12 o’clock (Figure 1).

Figure 1
figure 1

Seven weeks after surgery, a slit lamp view of the right eye shows a localised corneal epithelial oedema and the detachment of the Descemet’s membrane.

Full size image

Following discussion she was scheduled for right anterior chamber tamponade with air under local anaesthesia. The procedure was uneventful. Three paracenteses to drain the sub-descemet fluid were performed. The anterior chamber was filled with filtered air in its entire volume and Provisc was used to cover the internal aspect of the corneal incision. The patient was asked to keep a postoperative face-up position for one week and took Acetazolamide sustained release 250 mg stat dose that evening. The following day, her right eye was comfortable, the corneal epithelial oedema had cleared and the Descemet’s membrane appeared to be reattached completely. There was a small wrinkle of the Descemet’s membrane running from the phacoemulsification corneal wound inferiorly (Figure 2).

Figure 2
figure 2

One day after surgery, slit lamp view shows a clear cornea. The edge of the Descemet’s membrane is still visible running inferiorly.

Full size image

One week after the anterior chamber reformation her right visual acuity was 6/24 unaided improving to 6/9 with −3.00/+1.25 × 55°. The Descemet’s membrane remained attached and the cornea was clear, her intraocular pressures were 10 mmHg in the right eye and 12 mmHg in the left eye.

Comment

DMD is not an uncommon complication after cataract surgery.3 Vastine et al suggest surgical intervention for large planar and scrolled detachments.4 Walland et al also recommend repair of large DMD should it be recognised intraoperatively, and that an expanding gas should be used.5

In this case the patient underwent routine, small incision phaco-emulsification cataract surgery with foldable lens implant and developed persistent corneal oedema. The DMD was not noted until the seventh week postoperative visit and appeared to have been progressive. The signs of DMD were very subtle and the examination was made more difficult by the extensive corneal oedema giving poor details of the anterior chamber. This patient responded well and promptly to anterior chamber reformation with air, with an almost immediate reattachment of the Descemet’s membrane. We used air to fill the anterior chamber after a three port paracentesis to drain the sub-Descemet’s membrane fluid. Once the Descemet’s membrane was attached to the corneal stroma the incision was covered internally with Provisc.

In summary, DMD can be a cause of corneal oedema and should be considered as a differential diagnosis in cases of corneal oedema following cataract surgery, especially if the procedure has been uneventful. One will need to examine carefully, as the signs of DMD can be subtle especially if masked by extensive corneal oedema. DMD can be reattached successfully using only air tamponade with good visual outcome.