Anterior Chamber and Pupil

A N T E R I O R C H A M B E R AND P U P I L . MARCUS FEINGOLD, M. D., F. A. C. S. NEW

ORLEANS.

This section reviews the literature of 1917 regarding the anterior chamber and its contents, and the pupil and pupillary movements. Closely related material may be found1 in the sections dealing with the uveal tract, the visual tracts and centers, tumors, and injuries of the eye. DEVELOPMENT

OF ANTERIOR

CHAM-

BER.—This has been studied by Speciale-Cirincione in a large number of human embryos. It is closely connected with the development of the cornea, ciliary muscle, iris angle, and pupillary membrane, none of which exist before the beginning of the second month of embryonic life. At that time, between the crystallin vesicle and the ectoderm, appears a layer of large cubic elements, the beginning of the posterior layer of the cornea. A little later a ring of thickening appears in front of this layer, the beginning of the true corneal tissue. A little later a mass triangular in section forms back of this layer on the anterolateral surface of the crystallin, and becomes vascular. At the tenth week the pigmented external layer of the optic vesicle becomes thickened at its margin, and undergoes rapid growth, advancing in front of the crystallin. Between it and the endothelial cushion in front, appears tissue that develops into the ciliary body. During the third month it becomes possible to distinguish a lamina similar to that of the corneal endothclium, which becomes the endothelial layer of the iris, and these two endothelial layers become separate.d, leaving the beginning of the anterior chamber. Shortly after the formation of this primitive fissure, spaces appear in front of the endothelial cushion which ultimately become the canal of Schlemm. At the end of the fourth month the cornea and ciliary body are well distinguished, the crystallin has assumed its proper form and the canal of Schlemm is present. But the iris and anterior chamber remain very rudimentary. From the fourth to the seventh month the anterior chamber gradually in-

creases its size corresponding with the increase in the surface of the iris. At the end of the seventh month the pupillary membrane still adheres to the cornea, but this adhesion is becoming weakened and its easy separation accounts for the view that the anterior chamber is already complete. By the eighth month the pupillary membrane has become less vascular, and sometimes is completely atrophied. After this, altho the anterior chamber is complete, it remains very shallow, becoming deeper after birth. AQUEOUS HUMOR. — Secretion. Analyzing in detail the experiments made to determine the secretion of the aqueous humor and passing criticism on all theories advanced as to its origin and the ways of its leaving the interior of the eye, Magitot (4) arrives at the conclusion that the experiments so far conducted do not sufficiently reproduce normal conditions and that the conclusions consequently do not apply to the normal aqueous humor. The renewal of the aqueous is very slow and there is no true current of the aqueous. During the third and fifth month of embryonic life the first aqueous is secreted by special neuroglial cells of true holocrin nature which accompany the hyaloid vessels. The fluid thus formed fills the meshes of the vitreous body, the anterior and posterior chambers. The fibrillary network of the vitreous is- nothing but retinal neuroglia. After the cells have disappeared the aqueous in later life is only very slowly absorbed and the deficiency is replaced by products of the retinal neuroglial cells, the cells of the ora serrata and the clear cells of the ciliary body. The eyeball has independent lymph channels for the anterior and posterior portions in the form of perivascular sheaths. Lymph and aqueous hu-

DIGEST OP T H E L I T E R A T U R E

ss

mor ate two different fluids. They do able clinically. Goldberg considered the not come in direct contact and they do iris had been too deeply invaded by the not mix. When the anterior chamber is growth to make radical removal posemptied by puncture the fluid filling the sible. chamber consists of serum transudate REMAINS OF PUPILLARY MEMBRANE. from the capillaries with an admixture —Jackson's two cases of slight remains of normal aqueous humor which is of pupillary membrane are extremely squeezed out of the meshes of the vitre- interesting because they illustrate how ous body. Gradually the serum is elimi- easily these conditions can be overnated and the neuroglial cells dialyze looked even by careful examiners and slowly new normal aqueous. even during repeated examinations. In By means of special forceps, Seidel the one case a brown mass was found near the upper edge of the pupil, apparclamped the iris to the lens, thereby closing the communication between the ently connected with the sphincter reposterior and anterior chambers. A gion and lying in front of it, together watch glass placed over the eye pre- with a fine line on the anterior capsule. vented the iris from getting dry; after In the other patient a fine thread conseveral minutes' observation no mois- necting two points of the anterior surture could be seen on the iris. Over face of the iris was only visible with the iris a small glass bell was placed dilated pupil, but was lying entirely in for several minutes; no moisture could front of the iris and difficult to see as be seen. A small ear speculum with a long as the pupil was contracted. Rid12.0 D. lens was placed on the iris; ley reports a case in which a mass of after several minutes a reflex appeared pigment was present in the anterior »n the middle of the iris and on the iris chamber. margin, which reflex disappeared after CENTERS OF P U P I L MOVEMENTS.— careful sponging. From this can be Dunn proposes a new theory of the concluded that only very scant secre- paths for the pupillary reflexes. The tion of the iris exists which can be es- direct light reflex or "the primary light timated to be about 17 milligrams or reflex" is, according to him, a reflex beabout one-fourth of a drop per minute. longing to the automatic system, a The secretion of the ciliary body, on vegetative reflex. Its path is: Retina, the other hand, can be estimated to be nerve cells to the pigment layer and about three-fourths drop per minute. along this to the ciliary region, where I hese measurements were made with impressions are made upon the sensthe ocular tension -equal to zero and ory nerve terminals therein, which imconsequently under conditions favor- pressions are conveyed to the ciliary "ig increased secretion. The normal ganglion, where they arouse efferent imsecretion, therefore, is very infinitesi- pressions along its motor fibers to the mal. These experiments do not per- sphincter pupillae. The consensual light mit the statement that the normal ocu- reflex is the result of nature's effort to lar tension is sufficient to prevent fil- obtain for any object directly looked at tering from the iris vessels. a like illumination in both eyes. Its CYST IN ANTERIOR CHAM HICK. - T h e path is: Retina, optic nerve, chiasm cyst in the anterior chamber in Gold- and tracts; from here a part goes to the berg's case developed after a perfor- center in the geniculate and quadriating wound of the eye, was of the geminal regions and then the fibers pearl tumor type and consisted of epi- pass to the third nerve nuclei. Anthelium and connective tissue which other part of the visual fibers goes to had been carried into the anterior the sympathetic subthalamic ganglion, chamber through the wound at the for the purpose of stimulating the actime of the accident. Two operations tion of the sympathetic on the dilator were performed, each time parts of the. iridis. It is possible, lie says, that the jris were removed with the tumor. cones represent the terminal mechan1 ho vision was good and extension ism for the reception ()f the impulses to »uo the deeper structures not notice- the geniculate and quadrigeminal nu-

ANTERIOR CHAMBER AND P U P I L

56

clei, and the rods of the impulses to the subthalmic ganglion. MYDRIASIS FROM NASAL OBSTRUCTION.

—-Lopez's patient, a teacher, suffering with hypertrophy of the inferior turbinates, worse on the left side, showed during the attacks a certain parallelism between nasal obstruction, and diminution and discomfort of vision which compelled him to take off his glasses and to clean especially the one corresponding to the left eye. Improvement of vision followed with a reduction of the respiratory trouble. During the attacks the right pupil was normal, the left one was wide and did not respond to light or accommodation. No other nervous symptoms were present. A few minutes after the application of cocain and protargol to the nares the mydriasis disappeared and both pupils reacted again normally. These symptoms were, according to Lopez, due to a spasm of the dilator pupillae as a result of an irritation of the sympathetic system started in its ramifications in the nose. MIOSIS—PARALYSIS

OF

CERVICAL

SYMPATHETIC.—Continuing their investigations of sympathetic nerve paralysis (Y. B., Vol.-12, 1915, p. 349), Metzner and Wofflin arrive at the following conclusions: Following the extirpation of the superior cervical ganglion in the rabbit, the difference in the size of the pupils is permanent, while the vascular symptoms in the ear are only transitory. Mild stretching of the cervical sympathetic in the rabbit produced oculo-pupillary symptoms, which will disappear entirely at times. Depigmentation of the iris did not occur in any of the experiments in which the superior cervical ganglion had been extirpated or the nerve severed below. Miosis was a regular occurrence after middle ear evisceration. The vascular symptoms following destruction of the middle ear disappear after a while and the oculo-pupillary symptoms remain. The experiments on the rabbit give results similar to those gained by clinical observations on the human being; that the vascular changes will disappear while the oculo-pupillary symptoms remain unchanged. This is explained on

the assumption that the muscular apparatus of the blood vessels forms an independent and regulating tonus producing apparatus. The muscle fibers of the iris do not regain their tonus and they cannot be classed with the muscle fibers of the blood vessels oi> account of their different embryonic origin. PHYSIOLOGIC INEQUALITY OF PUPILS.

—While both pupils are of the same size when the eyes are looking forward, Tournay finds that if the eyes look to one side, the pupil of that side becomes larger after a short while, while the other pupil contracts. ARGYLL ROBERTSON PUPIL.—On

the

basis of his theory of the pupillary reflexes Dunn (see above), gives the following explanation for the Argyll-Robertson pupil: The specific toxins of lues have a selective action on the ciliary ganglion and if the lesion is here confined to the sensory elements, we have the abolition of the primary reflex of the ciliary ganglion which gives us the Argyll-Robertson pupils. After destruction of the sensory-motor and sensory-sympathetic connections in the ciliary ganglia motor impulses from the third nerve nuclei can still reach the sphincter of the pupil with the result that the Argyll Robertson pupil is a contracted one. While the sympathetic connections with the ciliary ganglia are destroyed, impulses from the sympathetic subthalamic centers can still reach the sphincter muscles via the long ciliary nerves and this explains why the pupils are kept equal during accommodation. If the toxins affect one ganglion more than the other, or sooner than the other, inequality of the pupils is the result. HEMIANOPIC P U P I L REACTIONS.—Ap-

plying his theory of the paths of the pupillary reflexes to the hemianopic pupillary reaction Dunn says: "If the lesion is in the optic tract anterior to the point where the fibers to the corpora quadrigemina and subthalamic ganglia are given off, the consensual light reflex is abolished for no retinal born impulses can reach the quadrigeminal region." The primary light reflex is abolished as soon as "degeneration of the retinal cells takes place. The pri-

DIGEST O F T H E L I T E R A T U R E

sr

catatonic stupor. Weslpha! found the pupil horizontally oval and with diminished light reaction ; he called it catatonic stiffness of the pupil. This change of the pupil has also been found in catatonic excitement by Albrand. Pressure on ovarian points produces dilatation of the pupil with absence of light reaction, according to E. Meyer. Reichmann in her own examinations found 61 cases with unusually large and 31 with very small pupils; in 47 cases the pupils were not round; they were unequal in 30 cases and eccentric in 17 cases; hippus was present in 8. In the normal individuals she found 20 very large and 14 very small pupils; 15 times the pupils were not P U P I L I N DiiJViENTiA P K K C O X . -In a study of the disorders of the pupil in round and 19 times unequal. In 11 dementia precox Reichmann enumer- cases the pupils were eccentric. In membranous occlusion after an inates the observations of others. The psycho-reflex (dilatation of pupil with fection, following cataract operation, mental effort, effects, etc.), and the re- Ziegler succeeded by the use of phylaflex enlargement after sensory stimuli cogen injections to produce complete were often found absent by liumke in absorption of the exudate. mary light reflex cannot then he aroused by the impact of light on the blind halves of the retina. Because, owing to the degeneration of the retinal fibers to those areas, there is mi activity in the pigment cells in response to light rays." If the lesion be posterior to the point where the fibers to the third nerve and the subthalamic ganglion are given off, primary and consensual reflexes are present from the blind area because "degeneration of the optic fibers anterior to the corpora quadrigemina and the subthalamic ganglion do not take place and the retinal cells remain responsive to light impulses."

T H E UVEAL TRACT. ClIAUI.ES ZlMMEKMANN, M . I ) . , F . A . C. S . MILWAUKEE,

WISCONSIN.

This section reviews the literature of diseases of the uveal tract for the year 1917. Sympathetic uveitis will be considered in the section devoted to Sympathetic Disease; and many important papers hearing upon the etiology of uveal inflamations will be noticed in the section upon Genera! Diseases, which will appear later in the year. A N O M A L I E S - H E T E K O C I I K O M I A IklDIS.--

Ellett reported 6 cases of heterochromia iridis, 2 of these with uveitis, 2 with cataract, and 2 with cataract and glaucoma. These pathologic changes occurred, as always, in the lighter colored eye. The difference in color may be due to the fact that no pigmentation takes place in one eye; or that it has been present, but is subsequently lost through some pathologic process. Ellett thus summarizes these changes: 1. Evidence of a chronic low grade cyclitis.—Rarely is there any ciliary injection or manifest changes in the iris or choroid, or subjective symptoms, such as would attend these changes. What we do find are vitreous opacities

and deposits on the posterior surface of the cornea. In Ellett's experience, the vitreous opacities are much the more frequent. 2. Development of cataract.—The peculiarities of this cataract are, in the first place, the youth of the patient, since it generally appears before the age at which we would expect to see cataract. It would be well to examine carefully the cases of juvenile cataract, not of the zonular type, and cataract occurring in persons under fifty, and limited to one eye, for evidences of heterochromic cyclitis. Another peculiarity of this cataract is that the other eye is, and remains, free from a similar disorder. The cataract pursues an ir-