Studies of the Angle Kappa and the Angle Alpha
- Conditions
- No Eye Disorder
- Interventions
- Other: Eye examination
- Registration Number
- NCT04886219
- Lead Sponsor
- Assistance Publique - Hôpitaux de Paris
- Brief Summary
Anatomical ophthalmological connections and their dynamics are still debated in the scientific community. However, their considering is essential in many surgeries (strabismus, cataract, refractive...) or in clinical practice.
The correlation between these biometric values would make it possible to refine the knowledge related to these landmarks and thus offer better ophthalmological management by integrating these variables into the clinical examination.
The aim of the study is to analyze the correlation between the angle alpha and the angle kappa in a healthy individual without ophthalmologic disorder.
- Detailed Description
The angle kappa corresponds to the angle formed between the visual axis (line between the point of fixation and the fovea: area of the retina allowing precise vision) and the pupillary axis (line passing through the center of the pupil and perpendicular to the cornea). The angle alpha corresponds to the angle formed between the visual axis and the optical axis (line passing through the nodal point of the eye and corneal center).
In theory, the angle kappa and angle alpha are equal; but physiological corectopy in the nasal position induces a variation between these two angles; the angle kappa being generally less than the angle alpha without a correlation being established. Also, pupillary constriction causes a variation in the position of the center of the pupil. The angle kappa therefore exhibits a variation depending on the expansion.
Anatomical ophthalmological connections and their dynamics are still debated in the scientific community. However, their considering is essential in many surgeries (strabismus, cataract, refractive ...) or in clinical practice.
The correlation between these biometric values would make it possible to refine the knowledge related to these landmarks and thus offer better ophthalmological management by integrating these variables into the clinical examination.
The aim of the study is to analyze the correlation between the angle alpha and the angle kappa in a healthy individual without an eye disorder.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 70
- Informed major subject not opposing to their participation in the study
- Subject with strabismus or organic ophthalmologic pathology
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Arm && Interventions
Group Intervention Description Healthy individual Eye examination Healthy individual
- Primary Outcome Measures
Name Time Method Value of the angle Alpha Day 0 Semi-automatic digital method of measurement by eye photography
Value of the angle Kappa Day 0 Semi-automatic digital method of measurement by eye photography
- Secondary Outcome Measures
Name Time Method Correlation between the value of the angle Alpha and the Optic disc / fovea distance Day 0 Angle Alpha value using the semi-automatic method of measurement by eye photography and the distance between the optic disc and the fovea
Variation of the Kappa angle depending on the pupillary diameter Day 0 Variation in the same individual. Value of the Kappa angle using the semi-automatic method of measurement by ocular photography in photopic and scotopic conditions \& measurement of the pupillary diameter using the photographs obtained
Correlation between the angle Kappa and the axial length Day 0 Value of the angle Kappa and Alpha using the semi-automatic method of measurement by eye photography and Value of the axial length measured by biometry IolMaster 500 (Carl Zeiss)
Trial Locations
- Locations (1)
Hôpital Necker-Enfants Malades
🇫🇷Paris, France