Text-book of ophthalmology . so doing they first passbehind the caruncle, and converging more and more, at length reach thelachrymal sac. Into this they empty, either separately or after havingunited to form a short common trunk. The lachrymal sac (saccus lacrimalis) lies in the inner angle of the eyein the cleft (fossa sacci lacrimalis) which the lachrymal bone forms for itsreception. The lachrymal bone bounds the lachrymal sac (S, Fig. 284) G99 700 TEXT-BOOK OF OPHTHALMOLOGY nasally, while to the front and temporally it is inclosed by the two branchesof the ligamentum palpebrale mediale (v a
Text-book of ophthalmology . so doing they first passbehind the caruncle, and converging more and more, at length reach thelachrymal sac. Into this they empty, either separately or after havingunited to form a short common trunk. The lachrymal sac (saccus lacrimalis) lies in the inner angle of the eyein the cleft (fossa sacci lacrimalis) which the lachrymal bone forms for itsreception. The lachrymal bone bounds the lachrymal sac (S, Fig. 284) G99 700 TEXT-BOOK OF OPHTHALMOLOGY nasally, while to the front and temporally it is inclosed by the two branchesof the ligamentum palpebrale mediale (v and h, Fig. 284). This relationof the lachrymal sac to the internal palpebral ligament enables us to deter-mine the position of the former—a matter which is of importance whenoperations are concerned. If by drawing the lids outward we put them onthe stretch and so cause the palpebral ligament to project, the lachrymalsac lies behind the latter, and in such a way as to rise just above it by itscupola or fundus (Fig. 294). F. Fig. 294.—Septum Orbitale and Lachrymal Sac. Natural size. The skin and the muscular fibers of the orbicularis have been removed from the lids and the partssurrounding them, so that the septum orbitale lies exposed to view within the bony circumference ofthe orbital cavity. The septum orbitale consists of the tarsus, which is broader in the upper lid, nar-rower in the lower, and of the fascia tarso-orbitalis. The external extremities of the tarsi are attachedby the broad, but not very dense rhaphe palpebralis lateralis to the malar bone, somewhat below thesuture, N, between this bone and the zygomatic process of the frontal bone. The internal palpebralligament is narrow, but stout; its anterior limb, which is the only one visible in the drawing, runsfrom the frontal process of the superior maxilla, S, outward, and divides so as to be inserted into theinner extremities of both the upper and lower tarsal cartilages. (At the point of insertion is seenthe som
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecteye, booksubjectophth
