Keratoconus Detection by Ultrasound
Condition: Keratoconus
MeSH terms: Keratoconus
Study type: Observational

Summary: 
      Keratoconus (KC) is a corneal disease which will in many cases ultimately require corneal
      transplantation to maintain vision. Early detection, which is not possible with current
      technology, would allow early treatment and prevent severe damage to KC corneas inadvertently
      operated upon for correction of vision. The investigators' aim is to combine measurements of
      different properties of the cornea to develop means for early detection of KC.
    

Detailed description: 
      Keratoconus is the most common degenerative disease affecting the cornea. As keratoconus
      develops, the cornea thins and bulges. Eventually, a corneal transplant may be needed to
      maintain vision. In its earliest stages, the disease is particularly difficult to detect.
      This is of great importance to the corneal refractive surgeon because surgical treatment of a
      keratoconic cornea will weaken it and greatly accelerate the occurrence of symptoms. Early
      detection of keratoconus will benefit patients because of the recent development of methods
      for strengthening the corneal stroma and preventing disease progression.

      The investigators have developed a technique based on the use of high resolution ultrasound
      for imaging the cornea and measuring the thickness of its component layers, including the
      epithelium and the stroma. In early keratoconus, as the anterior stromal surface begins to
      bulge forward, the epithelium will thin above the apex of the bulge and thicken around it, to
      maintain a smooth anterior surface. The investigators have also developed methods for
      characterizing the elastic properties of the cornea by inducing and measuring surface
      displacements in response to a pulse of acoustic radiation force.

      The investigators' goal is to reduce the percentage of screened cases deemed
      keratoconus-suspect by at least a factor of two by allowing an unambiguous diagnosis of early
      keratoconus. This would provide two major benefits; (1) to be able to predict eyes with
      higher risk of developing ectasia after corneal refractive surgery, and (2) early diagnosis
      would allow earlier treatment of the condition with collagen crosslinking, preserving the
      cornea from disease progression.
    

Intervention name(s): Artemis Ultrasound Exam; Optical Coherence Tomography (OCT) Exam
Intervention type(s): Procedure; Procedure
Intervention description(s): Ultrasound exam of both eyes using an Artemis-2 device. Exam will be performed once. Exam duration is 20 minutes per eye.; OCT exam of both eyes. Exam will be performed once, duration is 10. I utes per eye.
Other intervention name(s): Ultrasound biomicroscope (UBM); High frequency ultrasound; OCT
Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        Patients presenting to CUMC associated physicians and the London Vision Clinic.
      
Keywords: keratoconus; keratoconus-suspect; ultrasound exam; acoustic radiation force ultrasound exam