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بسم الله الرحمن الرحيم. ﴿و ما أوتيتم من العلم إلا قليلا﴾. صدق الله العظيم الاسراء اية 58. Physiology of Special Senses. By Dr. Abdel Aziz M. Hussein Lecturer of Medical Physiology Member of American Society of Physiology. Intraocular Fluids. Intraocular Fluids. Aqueous humour.
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بسم الله الرحمن الرحيم ﴿و ما أوتيتم من العلم إلا قليلا﴾ صدق الله العظيم الاسراء اية 58
Physiology of Special Senses By Dr. Abdel Aziz M. Hussein Lecturer of Medical Physiology Member of American Society of Physiology Physiology of Special senses, Abdelaziz Hussein
Intraocular Fluids Aqueous humour Vitreous humour
The Aqueous Humour Transparent colourless alkaline fluid that fills the anterior and posterior chambers of the eye
The Aqueous Humour Mechanism of formation • Formed continuously by the Ciliary epithelium by facilitated diffusion and active transport mechanisms • Na by active transport • Cl and HCO3 and H2O follow Na passively • Rate • At a rate 1-2 µL/min
The Aqueous Humour Composition
The Aqueous Humour Circulation and drainage of aqueous humour
The Aqueous Humour Functions
Vitreous Body Hyaloid canal Retrolental space Capsule
Vitreous Body Functions
The Middle Layer or Uveal Tract
Uveal Tract Choroid Iris Ciliary ms
The Iris Iris
The iris Muscles of the iris Radial or Dilator Pupillae ms Circular or Constrictor Pupillae ms
Functions of the Iris The pigments of iris absorb all light rays which enter into the eye except though which pass through the pupil.
Functions of the Iris 2. It prevents light from falling on the peripheral parts of the lens. Thus it preventsspherical and chromatic aberration
Functions of the Iris 3. It regulates the amount of light which enters into the eye by regulating the size of the pupil. 4. Pupillary constriction increases the depth of focus i.e. the distance of the object can be changed but its image is still focused on the retina without change in accommodation.
Functions of the Ciliary Body 1. The ciliary muscle is essential for accommodation • 2. The ciliary processes secrete the aqueous humour into the posterior chamber & give attachment to the suspensory ligament of the lens.
Functions of the Choroid 1. It is a vascular layer which provides blood supply to the eye • 2. The pressure inside its vessels maintains the intraocular pressure • 3. It contains melanin pigments which absorb light & prevent its reflection inside the eye which cause blurring of vision