210 Cited by Robin, loc. cit., p. 74.
PTOSIS.—Paralysis of the branch of the third pair which supplies the levator palpebræ, when it exists without any lesion of the other branches or where it is coincident with hemiplegia of the opposite side, is frequently held to indicate a cerebral lesion, which may be either cortical or have its seat in the nucleus of the nerve. According to Grasset,211 when the lesion is cortical it is situated in the parietal lobe in advance of the angular gyrus. The localization is by no means well made out. Coignt212 has shown that it is not always crossed, for in 5 out of 20 cases mentioned by him it existed on the same side as the paralysis. Steffen213 gives a case of double ptosis with sluggish pupils where there was complete control over the muscles moving the globe, the autopsy showing a tubercle in the tubercular quadrigemina which had entirely effaced their normal structure.
211 Robin, p. 104.
212 Thèse de Paris.
213 Berliner klin. Wochenschrift, No. 20, 1884.
OPHTHALMOPLEGIA INTERNA.—In those cases where affection of the orbital ophthalmic ganglia can be excluded, paralysis of the pupillary and ciliary branches of the third pair is, according to Jonathan Hutchinson, due to an affection of the twig which runs through the lenticular nucleus in the striated body. It is frequently associated with paralysis of the internal rectus, and may be accompanied by paralysis of the ciliary muscle. After diphtheritis there is often paralysis of the ciliary muscle, with prompt reaction of the iris. The writer is not aware of any recorded instance of apoplexy or other sudden onset of disease which would enable us to localize exactly the centre for pupillary contraction. According to Hughlings-Jackson, we may have in apoplexy the most varied states of the pupil (normal, dilated, or contracted) independent of the seat of lesion: he further states that upon calling loudly to the patient there will sometimes be a transient pupillary dilatation. When we look at the state of the pupils as part of general symptomatology, we find a most perplexing confusion and contradiction: in fact, notwithstanding the quantity of material both in ancient and modern literature, we are far from having any satisfactory account of the subject. This is partly due to our imperfect knowledge of the anatomy of the brain and to the great difficulty of estimating exactly pupillary changes, and partly carelessness and want of a proper system of observation. The data have for the most part been hastily compiled, without a minute statement of concomitant symptoms or the stage of the disease in which they are developed. Usually, they have been made without any proper means for illuminating the pupil or apparatus for correctly magnifying and observing its motions. In most cases the want of knowledge of the more common sources of error, such as a difference in the size of the pupils owing to difference in the refraction of the eyes, posterior synechiæ, or other intraocular changes, has invalidated the results.
ASSOCIATED MOVEMENTS OF THE HEAD AND EYES.—In many central lesions, associated movements of the head and eyes are present, and, although the exact channels through which they are propagated are for the most part unknown, yet certain groups of these clinical symptoms are of so frequent occurrence as to be recognized and admitted by almost all observers. Vulpian and Prévost were the first to enter into a minute study of these movements. Vulpian in his lessons on the physiology of the nervous system (1866) states that "in cases of unilateral cerebral lesion, whether it be situated in the cerebral hemispheres, the striated bodies, the thalami optici, the cerebellum, or in the different parts of the isthmus cerebri, whether the lesion be softening or hemorrhage, there is often, immediately after the attack, a deviation of the eyes at the time of development of the hemiplegia. The deviation is in general transient, and may last either a few minutes or hours or several days. The eyes are usually turned in a direction opposed to that of the hemiplegia; thus, if the right side is paralyzed, both eyes are turned toward the left. On regaining consciousness the patient, if he tries to turn his eyes to the right, may either be entirely unable to move them, or, what is more usual, may succeed in bringing them to the middle of the palpebral aperture without being able to turn them farther in that direction. Does this phenomenon depend on a paralysis of the muscles which cause conjugate motion of the eyes, or on a spasmodic contraction of their opponents, over which they are unable to triumph?" He further states: "I incline strongly to the latter view, as it is in accordance with what we observe in animals. The analogy of the phenomena goes still farther: often the head of the patient has made a more or less marked movement of rotation on the neck—a movement as the result of which the face is turned toward the non-paralyzed shoulder, and in the cases where we cannot observe a deviation by turning back the head into its normal position, an action which can often be only brought about by considerable effort."
Prévost214 has since formulated the following laws for cases of hemiplegia: "I. When the hemiplegic looks toward his lesion and away from his paralyzed side, the lesion is hemispherical. II. If he looks toward his paralyzed side, the latter is situated in the mesencephalon." This statement coincides with the facts reported by Hughlings-Jackson, Charcot, and many other observers. Nothnagel215 admits that this is the rule, but quotes as an exception to it a case of his own where, with right hemiplegia and head turned to the right, the eyes were turned to the left, the autopsy showing an extensive patch of softening in the left hemisphere which involved the frontal convolutions, the central convolution, and the adjacent white substance. In addition, he cites Bernhardt as giving other exceptional cases which, in his own judgment, "considerably diminishes the diagnostic value of the phenomenon." Landouzy and Coignt216 have attempted to define still more clearly the diagnostic value of the associated movements of the head and eyes, and, while they admit the correctness of these laws of hemiplegic paralysis, they add that in convulsive cases in which there are symptoms of irritative lesions the above rules are reversed. To explain such cases they lay down the following rules: first, that if the patient looks toward his convulsed side the lesion is situated in the hemisphere of the opposite side; and second, if he looks away from his convulsed side (or toward the lesion) there is an irritant lesion of the mesencephalon.
214 Thèse de Paris.
215 Topische Diagnostik der Gehirnkrankheiten, p. 580, 1879.