XXVIII. ANATOMIC RELATIO~S OF THE CAVERNOUS SINUS TO OTHER STR1JCTlJRES, WITH CO~­ SIDERATION OF VARIOUS PATHOLOGIC PROCESSES BY WHICH IT ::\1 AY BE­ COME INVOLVED.* By HENRY GLOVER LANGWORTHY, l\J. D.. DUBUQUE, IowA. The object of this paper is to present as c1e'J.r a picture as possible of the anatomic relations of the cavernous sinus to adjacent structures, and to' index in one article, as far as pos­ sible, the scattered data of pathologic affections available in the literature of the past fifteen years, together with the im­ portant addition of unpublished information obtained from question-letters sent to prominent general surgeons through­ out the country. The idea of instituting a search of this kind grew out of the fact that in reading a paper on "Cavernous Sinus Thrombosis and the Future," before the Chicago Oph­ thalmological Society, November, 1914, the discussion s<!emed to indicate: First, that while most. of us were pretty well informed so far as one or two diseases of the sinus was con­ cerned, our information stopped quite abruptlly at that point; second, that deductions from individual experience was ex­ tremely limited; and, third, that possibly statistics with refer­ ence, at least to mortality in septic thrombosis of the sinus, might not be accurate. Because of the speculation and the rather chaotic condition of literature, the writer determined to investigate the subject more fully, and to present such mat­ ter as could be gathered, even though the result& obtain~d mig-ht not prove in the end worth the labor involved. With this preliminary statement, therefore, such material as has been gathered is herein presented. -Read before the Chicago Laryngologlcal and Otological Society. December 21, 1915. Downloaded from aor.sagepub.com at Bobst Library, New York University on May 8, 2015 Rl':I,ATIONS OF CAVERNOUS SINUS TO OTHER STRUCTURES. 555 ANATOMY. The cavernous sinuses, two in number, one on each side of the sella turcica,* are a part of the general venous system at the base of the skull. Like the other large venous channels, they are situated between two layers of the dura (splitting of the dura), are lined by endothelium continuous with that which lines the veins generally, and serve to drain the blood anteriorly from about the orbits, and anterosuperiorly from the brain itself. These sinuses carry the bulk of this venous flow backwards through the petrosals to the internal jugular veins, the great outlet for the cerebral circulation. Their anatomic importance depends upon their location in the middle cranial fossa, just lateral to the body of the sphenoid bone, extending from the sphenoidal fissure in front to the apex of the petrous portion of the temporal bone behind, containing venous blood, and being traversed by certain other (transient) structures and being connected internally with each other by communi­ cating small intercavernous sinuses which at the same time surround the hypophysis cerebri. The cavernous sinuses are so named because they present the picture of a reticulated structuret traversed by numerous interlacing filaments which divide the sinus cavity into irreg­ ular compartments. The sinuses are larger behind than in front and measure from two to two and one-fourth centimeters in length, and have a diameter of about one centimeter. A cross section shows these sinuses to be of such shapes as :juadrilateral, shallow S outline, or distinctly tooth shaped. As l expressed by Piersol : "Its external diameter does not repre- ·Sella turcica (Turkish saddle)-the depression within the three clinoid processes of the sphenoid bone lodging the pituitary body. t As a clear mental picture of the sinus Is important for proper clinical application in disease, It is worth repeating with Halstead that anyone "who has dissected the cavernous sinus w1ll realize that It Is not a single cavity, but it is a ainus made up of a number of cavities-from one to fourteen separate cavities, con­ nected by a very small opening, so that you may open and scrape out one of these cavities and st1ll leave others that are infected and continue to spread infection." J. C. Beck has also emphasized the fact that In attempted drainage of the sinus we must take this partition idea into consideration, for in instituting any drain­ age which might be successful the sinus must be drained as thor­ oughly as any other thrombotic vessel and that It would be ex­ tremely doubtful whether a small slit or puncture in one of these partitions would really accomplish much good. Downloaded from aor.sagepub.com at Bobst Library, New York University on May 8, 2015 556 HltNRY GLOVER LANGWORTHY. sent the actual capacity of the lumen, since this is greatly reduced in size: (a) by being traversed by numerous trabeculae from which fringe-like prolongations hang freely in the blood current, a section of the sinus having very much the appear­ ance of a section of the corpus cavernosum of the penis, whence the name bestowed upon it by Winslow; and (b) by the fact that the internal carotid artery and abducens nerve tra­ verse it, while other cranial nerves are imbedded in its outer wall." Anteriorly each cavernous sinus receives as tributaries the ophthalmic vein (through the sphenoidal fissure), spheno­ parietal sinus, lodged in the dura on the under surface of the lesser wing of the sphenoid, and a smaller cerebral vein (vena cerebri media and sometimes vena cerebri inferior). An­ teriorly the sinus is in direct communication with the angular vein at the inner angle of the orbit through the superior oph­ thalmic vein. Posteriorly the cavernous sinuses tenninate by opening into the superior and inferior petrosal sinuses at the junction of the petrous and sphenoid bones (foramen petrosphenoidale). The cavernous sinus communicates with the lateral sinus by lJ1eans of the superior petrosal sinus; with the internal jugu- . Jar vein through the inferior petrosal sinus, and through a plexus of veins on the internal carotid artery (Gray'); and with the pterygoid plexus through the foramen ovale. Internally the two sinuses communicate with each other by means of the intercavernous sinuses (anterior and posterior intercavernous sinuses, with at times a third or inferior inter­ cavernous sinus). The. internal surface has anywhere from three to seven openings by which it communicates with its fellow on the opposite side and also with the hypophysis cere­ brio On the inner wall within each sinus is found the internal carotid artery, accompanied by filaments of the carotid plexus and the abducens nerve. The communication also between the two anterior ends of the inferior petrosal sinuses at the pos­ terior extremity of the cavernous by the plexus basillaris (or so called transverse sinus) is another anastomotic connection which tends to equalize and distribute blood pressure for the larger cavernous. The external or outer wall of the sinus is occupied by the oculomotor, trochlear, ophthalmic and superior maxillary Downloaded from aor.sagepub.com at Bobst Library, New York University on May 8, 2015 RELATIONS OF CAVERNOUS SINUS TO OTHER STRUCTURES. 557 divisions of the trigeminal nerve. All such structures, how­ ever, are separated from the blood flowing through the sinus by the endothelial lining membrane continuous with the inner coat of the veins previously mentioned. Summing up it may be said that the transitional structures of the cavernous sinus number seven in all-i. e., internal car­ otid artery, carotid plexus, abducens, oculomotor, trochlear, ophthalmic, and superior maxillary nerves. The upper three-fourths of the external surface of the sinus is in relation to the internal part of the temporosphenoidallobe, while the lower one-fourth is in relation to the inferior maxil­ lary nerve (mandibular branch). The superior border of the cavernous sinus is in relation in the posterior four-fifths with the dura covering the cavern­ ous portion of the oculomotor nerve, and in the anterior one­ fifth with the lacrimal nerve. The inferior border is said to be "formed posteriorly by endothelial lining membrane being reflected on the intracranial portion of the nervus maxillaris." S (Hoeve. ) Relation of Structures in the Cavernous Sinus.-As out­ lined by Hoeve,s in the posterior four-fifths of the sinus, from above downward, the oculomotor, trochlear and ophthalmic nerves rest against the internal surface of the outer wall. The carotid artery, surrounded by the carotid plexus and the nervus abducens, rests against the internal wall, and the plexus cav­ ernosus lies internal to the carotid artery. In the anterior one-fifth of the sinus the oculomotor nerve and the ophthalmic (first division of the fifth) divide into their branches within the sinus at the junction of the posterior four­ fifths with the anterior one-fifth, and this breaking up into .branches is the cause of the difference in relations in the sinus and the fissura orbitalis superior.* -Dissection (trom Manual of Dissection and Practical Anatomy of the Head and Neck, Hubertus J. H. Hoeve, edition 1910, pages 347-3~9) : (1) Incise dura carefully along the superior border of sinus cavernosus, but do not cut the llgamentum petrosphenoldale at the posterior extremity of the sinus, which bridges over the Interval between the apex of the petrosK and the base of the processus cl1noldeus posterior, and which II covered only by dura In that reglon. (2) Redect the llap of dura outward and downward and expose the Interior of the sinus, and by breaking down carefully some of Downloaded from aor.sagepub.com at Bobst Library, New York University on May 8, 2015 558 HENRY GI.OVER LANGWORTHY. Variations of the Cavernous Sinus.-According to Quain (as quoted by :\losher): "The cavernous sinus is represented in a child by a venous plexus in the dura mater, which by en­ largement and fusion of its channels is converted into the char­ acteristic sinus of the adult.