Case 25 afforded me a not altogether pleasant surprise. Martin M—, æt. 58, has matured cataract in the right eye, with perfectly satisfactory light reflex, proper projection, &c. On the left progressive cloudiness of the lens has begun. The course of operation and cure were regular in every respect, but the power of vision finally was so small that with a clear pupillary area, and otherwise normal condition, only single words of No. 3·0 were recognised with difficulty at 10 to 15 cm. with convex 20 D. For the first time the patient remembers that he noticed the defective sight in his right eye at the age of sixteen, and was for this exempt from army service. The operation performed later on the left eye procured satisfactory vision.
C. Visual acuteness of less than 1/36 12 cases.
Determination of refraction of the better eye is given in 6 cases, and showed twice emmetropia, twice slight myopia, twice hypermetropia. I only possess an exact ophthalmoscopic determination of the condition of the defective-sighted eye in one instance with H. 2·5 D.
This group is of special interest in that it represents the extreme degrees of congenital amblyopia, and, on the other hand, because it contains 5 cases of children under 10 years of age.
Case 26.—Constanze von M—, æt. 9-1/2. Defective vision on the left side had been noticed long before by the child's parents. On May 1, 1879, emmetropia was observed in right eye, V. 5/12 to 5/9. No. 0·4 is read at 15 cm. On the left, only movements of the hand are seen, fingers cannot be counted even when close to the eye; the visual field is good, that is, on moving the hand in the periphery of the visual field the child sees "something" without being able to state what it is. Reaction of the pupils as rapid and equal as usual. The ophthalmoscopic condition (even with dilated pupils) is perfectly normal. All tests for simulation were of course applied.
On account of the importance of the case, I suggested another examination a year and a half later, on the 22nd December, 1880, which showed precisely the same result as the former one—optic disc, macula lutea, &c., perfectly normal, the ophthalmoscopic determination of the refraction shows H. 2·5 D.
The child's father also possesses in the left eye a slight degree of congenital defective sight, observed for many years, with normal ophthalmoscopic condition; No. 0·5 is read with + 6·5 D. at 10 cm.
Case 27.—Tina S—, æt. 6. The defective sight of the left eye had been remarked some months previously; report on July 16th, 1878: R. full visual acuteness, L. movements of the hand are scarcely visible. The child cannot count fingers. Normal ophthalmoscopic condition. Eserine and separate use were prescribed. On September 9th, 1878, fingers were counted with the left eye at 1·5 m., single words of No. 4·0 were recognised, No. 3·5 with convex 6·5 D., but always with oscillating fixation. The improvement in the child's statements may be referred to the fact that she had meanwhile learnt to form right conclusions from the very imperfect sensual impressions of her left eye.
Case 28.—Frank J—, æt. 10. Left eye. V. 10/50 to 10/40, No. 1-1/2 Snellen is read at 4 inches. On the right, nystagmus on fixation, fingers are counted at 5-6 feet. The ophthalmoscopic condition is normal. A sister of the boy squints.
Case 29.—Ernest G—, æt. 8, has slight nebulæ on both corneæ. On the left V. 15/40. On the right, fingers are counted at 4 inches with visual axis deviating inwards.