Symptoms
Symptoms of regular astigmatism include: (i) defective vision; (ii) blurring of objects; (iii) depending upon the type and degree of astigmatism, objects may appear proportionately elongated; and (iv) asthenopic symptoms, which are marked especially in small amount of astigmatism, consist of a dull ache in the eyes, headache, early tiredness of eyes and
sometimes nausea and even drowsiness.
Signs
1. Different power in two meridia is revealed on retinoscopy or autorefractometry.
2. Oval or tilted optic disc may be seen on ophthalmoscopy in patients with high degree of
astigmatism.
3. Head tilt. The astigmatic patients may (very exceptionally) develop a torticollis in an attempt to bring their axes nearer to the horizontal or vertical meridians.
4. Half closure of the lid. Like myopes, the astigmatic patients may half shut the eyes to achieve the greater clarity of stenopaeic vision.
Investigations
1. Retinoscopy reveals different power in two different axis
2. Keratometry. Keratometry and computerized corneal topotograpy reveal different corneal
curvature in two different meridia in corneal astigmatism
3. Astigmatic fan test and (4) Jackson's cross cylinder test. These tests are useful in confirming the power and axis of cylindrical lenses .
Treatment
1. Optical treatment of regular astigmatism comprises the prescribing appropriate cylindrical lens, discovered after accurate refraction.
i. Spectacles with full correction of cylindrical power and appropriate axis should be used for distance and near vision.
ii. Contact lenses. Rigid contact lenses may correct upto 2-3 of regular astigmatism, while soft contact lenses can correct only little astigmatism. For higher degrees of astigmatism toric contact lenses are needed. In order to maintain the correct axis of toric lenses, ballasting or truncation is required.
2. Surgical correction of astigmatism is quite effective.
Symptoms of regular astigmatism include: (i) defective vision; (ii) blurring of objects; (iii) depending upon the type and degree of astigmatism, objects may appear proportionately elongated; and (iv) asthenopic symptoms, which are marked especially in small amount of astigmatism, consist of a dull ache in the eyes, headache, early tiredness of eyes and
sometimes nausea and even drowsiness.
Signs
1. Different power in two meridia is revealed on retinoscopy or autorefractometry.
2. Oval or tilted optic disc may be seen on ophthalmoscopy in patients with high degree of
astigmatism.
3. Head tilt. The astigmatic patients may (very exceptionally) develop a torticollis in an attempt to bring their axes nearer to the horizontal or vertical meridians.
4. Half closure of the lid. Like myopes, the astigmatic patients may half shut the eyes to achieve the greater clarity of stenopaeic vision.
Investigations
1. Retinoscopy reveals different power in two different axis
2. Keratometry. Keratometry and computerized corneal topotograpy reveal different corneal
curvature in two different meridia in corneal astigmatism
3. Astigmatic fan test and (4) Jackson's cross cylinder test. These tests are useful in confirming the power and axis of cylindrical lenses .
Treatment
1. Optical treatment of regular astigmatism comprises the prescribing appropriate cylindrical lens, discovered after accurate refraction.
i. Spectacles with full correction of cylindrical power and appropriate axis should be used for distance and near vision.
ii. Contact lenses. Rigid contact lenses may correct upto 2-3 of regular astigmatism, while soft contact lenses can correct only little astigmatism. For higher degrees of astigmatism toric contact lenses are needed. In order to maintain the correct axis of toric lenses, ballasting or truncation is required.
2. Surgical correction of astigmatism is quite effective.
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