Do not wear contact lenses for


days beforehand

What is it?

The pachymetry is an ophthalmological test that measures the thickness of the cornea, the clear membrane located at the front of the eye.

The cornea generally measures around 500 or 600 microns in the central area, and between 600 and 800 in the peripheral area. It is important to know the thickness of the cornea before certain types of surgery are performed. It is also a factor to be considered in the diagnosis and monitoring of certain corneal diseases or in cases of glaucoma.

How is it performed?

The test is performed using ultrasounds directed at the central part of the cornea, using a probe called a pachymeter (ultrasound pachymetry).

It is also possible to measure corneal thickness using an optical coherence tomography or OCT, which uses a laser for measuring and requires no contact with the surface of the cornea.

4 keys to the pachymetry

  1. It is a simple test but requires contact with the surface of the eye, which is why anaesthetic eye drops are applied to avoid discomfort.
  2. It can be performed with the pupil dilated or not dilated.
  3. Contact lenses should not be worn for more than 7 days beforehand.
  4. Duration of this test: 5 minutes.

What diseases can be diagnosed?

  • Monitoring of patients with glaucoma, as corneal thickness changes the measurement of intraocular pressure, which must be adjusted.
  • To prepare for refractive surgery and its post-operative monitoring (operations to correct refractive defects with laser techniques).
  • To track the evolution of corneal diseases (corneal oedema, dystrophies, keratoconus, etc.).
  • To prepare for and track corneal surgeries (corneal transplantation).

Associated treatments

IMO Institute of Ocular Microsurgery

Josep María Lladó, 3
08035 Barcelona
Phone: (+34) 934 000 700
E-mail: international@imo.es
See map on Google Maps

By car

GPS navigator coordinates:
41º 24’ 38” N – 02º 07’ 29” E

Exit 7 of the Ronda de Dalt (mountain side). The clinic has a car park with more than 200 parking spaces.

By bus

Autobus H2: Rotonda de Bellesguard, parada 1540

Autobus 196: Josep Maria Lladó-Bellesguard, parada 3191

Autobuses H2, 123, 196: Ronda de Dalt – Bellesguard, parada 0071

IMO Madrid

C/ Valle de Pinares Llanos, 3
28035 Madrid
Phone: (+34) 910 783 783
See map in Google Maps

Public transport

Metro Lacoma (líne 7)

  • Lines 49 & 64, stop “Senda del Infante”
  • Line N21, stop “Metro Lacoma”


Patient care:
Monday to Friday, 8 a.m. to 8 p.m.

IMO Andorra

Av. de les Nacions Unides, 17
AD700 Escaldes-Engordany, Andorra
Phone: (+376) 688 55 44
See map in Google Maps

IMO Manresa

C/ Carrasco i Formiguera, 33 (Baixos)
08242 – Manresa
Tel: (+34) 938 749 160
See map in Google Maps

Public transport

FGC. Line R5 & R50 direction Manresa. Station/Stop: Baixador de Manresa


Monday to Friday, 08:30 A.M – 13:30 PM / 15:00 PM – 20:00 PM

Make an appointment

We call you

Please provide us with the following details so that we can call you and help you in any way we can..