Morphological study of the accommodative apparatus in the monkey eye.

For more than a century there has been debate concerning the mechanism of accommodation--whether the lens capsule or lens material itself determines the functional relationship between ciliary muscle contractility and lens deformation during refractive adaptation. This morphological study in monkey eyes investigates the composition and distribution of several connective tissue components in the accommodative apparatus relaying muscle force to lens organization. Elastin distributes on the marginal surface of the ciliary process.

Developmental anatomy in the zonular connection with lens capsule in macaque eye.

Morphological analyses of zonule conjugated with lens capsule were performed on the developmental change in eyes from the age of fetus to 7 years old of the rhesus macaques (Macaca fuscata). The zonule was filamentous network in late fetus. After birth, the zonular microfibrils originated from the nonpigmented epithelium of the ciliary process.

Ischaemia in the Zinn-Haller circle and glaucomatous optic neuropathy in macaque monkeys.

Aims: To elucidate the morphological features of optic neuropathy in an ischaemic model of glaucoma in macaque monkeys.

Methods: The regional degenerative process was investigated by experimentally occluding the paraoptic branches of the lateral short posterior ciliary artery, that is, the circle of Haller and Zinn, in 11 eyes. Morphological changes in nerve fibres in the lamina cribrosa were evaluated by histopathology, immunocytochemistry and angiography, and the findings were compared with those observed in an aged macaque with spontaneous glaucomatous optic neuropathy.

Localization of papillofoveal bundles in primates.

Axons in the fovea are precisely organized to ensure accurate vision. We investigated the morphologic characteristics and localization of nerve bundles in the optic nerve in primates. Macaque eyes were studied for conventional and immunostaining, and also marmoset eyes for carbocyanine dye tracing.

Intracapsular organization of ciliary zonules in monkey eyes.

Ciliary zonules are responsible for changing the curvature of a lens in the dioptric focus of an eye. Present established theory is based on the relaxation of zonular superficial fasciculi affixed to the capsular surface, thereby inducing the change of anterior- and posterior lens curvature causing spontaneous liquid movement of lens material. To achieve precise focusing at any distance, a more active functional organization should exist.

[Morphological study of the crystalline lens in monkeys].

Purpose: The morphology of the crystalline lens was studied by conventional staining techniques. The thickness of the capsule, the features of epithelial cells, and the distribution of inter fibrillar connective tissue were observed.

Methods: Eight eyes of young monkeys were examined.

[Near triad measurement--accommodative pupillometry with horizontal eye tracking and its qualitative analysis].

Purpose: Recording of "near triad responses" was done by static accommodative stimulation to reveal the qualitative analysis of asthenopia.

Method: Twelve healthy subjects in agegroups of 20, 30, and 40 years were examined before and after several hours of visual display terminal (VDT) work after informed consent. Three trials of forward <-> backward movement of focusing on a target were carried out.

[Near triad meter--dynamic measurement of pupillometry with horizontal eye tracker by accommodative stimulation].

Purpose: A newly developed "Near Triad Meter" is a useful tool to record the dynamics of pupils and horizontal eye movements in both eyes simultaneously with the accommodative stimuli. The responses show insufficiency or strain for accommodation. In this study the objective accommodative power (in diopters, D) is calculated by the measurement of pupillary constriction-ratio(CR) and compared in 4 age groups to find the age-related decrement of diopter values.

[Immunohistochemical study of the extracellular matrices related to accommodation in monkeys].

Purpose: The mechanism of accommodation was studied by immunohistochemical staining of extracellular matrices in monkey eyes.

Methods: Frozen sections from five pairs of post-mortem eyes donated by physiologists were used. The antigens listed in Table 1 were selected, and a 2- or 3-step staining technique was used.