Topography Guided PRK in a Penetrating keratoplasty

Authors

Amélia Martins's picture
Author title: 
MD
Author name: 
Amélia Martins
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Author title: 
MD
Author name: 
Andreia Rosa
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Author title: 
MD
Author name: 
Esmeralda Costa
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Author title: 
MD
Author name: 
Cristina Tavares
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Author title: 
MD, PhD
Author name: 
Maria João Quadrado
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Author title: 
MD, PhD
Author name: 
Joaquim Neto Murta
Author affiliation: 
Centro Hospitalar e Universitário de Coimbra
Pathology: 
History of Present Illness (HPI): 

Man aged 38, diagnosed with bilateral keratoconus (KC) 21 years ago.
In 1996 he was submitted to a penetrating keratoplasty (PK) in the left eye (LE), due to a corneal central leukoma and best corrected visual acuity (BCVA) of less than 1/10 (Snellen), without complications. One year after LE PK, he had a clear graft, without neovascularization, uncorrected visual acuity (UCVA) of 5/10 and BCVA of 8/10 with -1.00 (+1.50 x 130º). BCVA improved to 10/10 with +1.00 (-3.25 x 40º) in the second year post-op.
In 2000, he had an uneventful PK in the right eye (RE) due to a corneal central leukoma. Two years later, the graft was clear and BCVA was 10/10 with (+2.50 x 120º).
In 2015, 19 years after LE PK and 15 years after RE PK, he was observed in the cornea consultation, where he had RE VA of 10/10 with +2.00 (-5.00 x 15º) and LE VA of 12/10 with -0.75 (-2.00 x 25º); both grafts were transparent and the remainder ophthalmic examination was otherwise unremarkable.

Past Medical History and Review of Systems (If relevant): 

There is a history of asthmatic bronchitis, treated with Salbutamol SOS.

Ophthalmologic examination: 

External examination and ocular motility were normal.
At the last visit, 15 years after PK in the RE, visual acuities were 10/10 with +2,00 (-5,00 x 15º)in the RE and 12/10 with -0,75 (-2,00 x 25º) in the LE.
Biomicroscopy showed clear grafts without neovascularization, deep anterior chambers, reactive pupils and transparent lens in both eyes.
Fundoscopy revealed C/D 0,5-0,6 in both eyes.
Intraocular pressure was 14 mmHg bilaterally.

Ancilliary tests: 

Corneal topography (Orbscan) revealed accentuated corneal astigmatism in the RE.

Corneal Topography of the RE before surgery
Diagnosis: 

High ammetropia after PK.

Treatment: 

The patient underwent topography guided photorefractive keratectomy (PRK) with mitomycin C 30 seconds in the RE. Post-operative medication included broad-spectrum topical antibiotic, fluorometholone 4id (tapered over 1 month) and lubrication.

Surgical plan (topography-guided ablation)
Evolution: 

There was a significant improvement of the refractive error after topography guided PRK, from a preoperative refractive error of +2.00 (-5.00 x 15º), to +0.75 (-1.50 x 20º) at 3 months post-op.

Corneal topography at 3 months post-op