Medical Blog

This is opacity of the lens which may be age-related or congenital,bilateral or unilateral.
In age-related catarct there is gradual development of lens opacity that usually develops during older age as the result of exposure to a variety of predisposing factors including:uv light,x-rays,cigarette smoke,diabetes mellitus,ocular trauma, uveitis, systemic drug therapy,e.g. Corticosteriods,chlorpromazine.
Congenital catarct may be due to genetic abnormality,e.g.downs syndrome,or maternal infection in early pregnancy,e.g.rubella.early treatment is required to prevent permanent blindness.
The extent of visual impairment depends on the location and extent of the opacicty.

This is the inability of the eyes to move together so that the same image falls on the corresponding parts of the retina in both eyes.the result is that two images are sent to the brain,one from each eye,instead of one intergrated image.it is caused by extraoculart muscles weakness or defective nerve supply to the muscle, i.e. defective cranial nerves 3,4 or 5.in most cases the images falling on the squiting eye is suppressed by the brain, otherwise there is double vision(diplopia).

1) EXTERNAL OTITIS:infection by staphylococcus aureus is the usual cause of localised inflammation (boils) in the external auditory meatus.when more generalised ,the inflammation may be caused by bacteria or fungi or by an allergic reaction to,e.g.,daddruff,saops,hairs sprays hair dyes.2) OTOSCLEROSIS:this is a common cause of progressive conductive hearing loss in loss in young adults that may affects one ear but is more commonly bilateral.it is usually hereditary,more common in females than in males and often worsens during pregancy.abnormal bone develops around the footplate of the stapes fusing it to the oval window,reducing the ability to transmit sound waves across the tympanic cavity.3) PRESBYCUSIS:this form of hearing impairment commonly accompainies the ageing process.degenrative changes in the sensory cells of the spinal organ (of corti) results in sensorineural (perceptive)deafness.perception of high-frequency sound is impaired first and later low frequency sound may also be affected.the individual develops difficulty in discrimmination,e.g.following a concervation,especially in the presence of background noise.4) LABYRINTHIS:this may be caused by development of a fistula from a cholesteatoma or rarely by spread of infection from the middle ear.in some cases the spiral organ is destroyed ,causing sudden total nerve deafness in the affected ear.5) MOTION SICKNESS:repetitive motion causes excessive stimulation of the semilunar canals and vestibular apparatus and results in nausea and vomiting in some people.6) DEAFNESS:hearing impairment can be classified in two main categories CONDUCTIVE and SENSORINEURAL.hearing impairment can also be mixed when there is a combination of conductive and sensorineural deafness in one ear. a) Conductive deafness:this is due to impaired transmmision of sound waves from the outside to oval window ,i.e.an abnormality of the outer or middle ear b) Sensorineural(perceptive)deafness:this is the result of diseases of the cochlea,the cochlear branch of the vestibular nerve or hearing area of the brain .the indiviual usually perceives noise but cannot discriminate between sounds,i.e.hears but cannot understand.    risk factors for congenital deafness  include:1) family history of hereditary deafness2) viruses,e.g.maternal rubella during the first 3months of pregancy 3) acute hypoxia at birth