Development of a laser doppler interferometer to investigate postnatal eye growth regulation / Gregor F. Schmid.

Format:

Book

Manuscript

Microformat

Thesis/Dissertation

Author/Creator:

Schmid, Gregor F.

Contributor:

Riva, Charles E., advisor.

University of Pennsylvania.

Language:

English

Subjects (All):

Penn dissertations--Bioengineering.

Bioengineering--Penn dissertations.

Local Subjects:

Penn dissertations--Bioengineering.

Bioengineering--Penn dissertations.

Physical Description:

xiii, 118 pages : illustrations ; 29 cm

Production:

1996.

Summary:

The precise and noninvasive measurement of intraocular distances in vivo is essential to investigate postnatal eye growth regulation, ocular shape and the development of myopia, one of the most prevalent vision problems facing the general population. For these purposes, an improved version of a previously described laser Doppler interferometer was developed for the measurement not only of axial eye length but also of the relative thicknesses of tissue layers of the ocular fundus comprising the retina, choroid and sclera with a precision of better than $\pm$20 $\mu$m. Advantages over ultrasound such as increased precision, superior eye alignment capability, lack of direct eye contact and the capability to obtain fundus contours by measuring off-axis are discussed. The anatomical loci responsible for the individual LDI peaks are identified in chicks. The high precision of LDI permits monitoring of previously undetectable phenomena such as daily and intraday changes in the thickness of the choroid and in axial eye length. These changes are characterized under various experimental conditions including normal visual experience, noninvasive optical image degradation by a translucent goggle to perturb the growth regulatory system, and selective denervation such as ocular parasympathectomy and sympathectomy. The responses to optical and surgical interventions is analyzed to elucidate the nature of the system(s) that regulate postnatal ocular development. It is demonstrated that the diurnal axial length rhythm is influenced by visual experience and may be related to eye growth control. Preliminary studies in humans are presented.

Notes:

Supervisor: Charles E. Riva.

Thesis (Ph.D. in Bioengineering) -- University of Pennsylvania, 1996.

Includes bibliographical references.

Local Notes:

University Microfilms order no.: 97-12997.

OCLC:

187469433