«OCULAR SIGNS OF MENINGIOMA* BY Frank W. Newell, M.D., AND (BY INVITATION) Thomas C. Beaman, M.D. A meningioma is a connective tissue neoplasm which ...»
OCULAR SIGNS OF MENINGIOMA*
BY Frank W. Newell, M.D., AND (BY
INVITATION) Thomas C. Beaman, M.D.
A meningioma is a connective tissue neoplasm which may involve the
meninges any place in the central nervous system. It is the second most
common brain tumor, only the glioma occurring more frequently.
Hoessly and Olivecrona (i) report that of 5,250 verified brain tumors
1,004 were meningiomas. The tumor is of particular interest to ophthal- mologists because of the frequency with which ocular symptoms first cause the patient to seek medical attention. Those meningiomas which occur at the base of the brain, particularly in the region of the sphe- noidal ridge and the tuberculum sellae, initially present eye signs which, if recognized promptly and treated appropriately, may well permit survival of the patient, since the tumor is usually histologically benign.
Meningiomas are also known as dural endotheliomas, meningeal fibroblastomas, meningeal fibroendotheliomas, and similar terms sug- gesting fibroblastic or mesothelial origin. The tumor occurs in two forms: (i) a global type which grows into and compresses nervous tissue, and (2) a carpet-like or en-plaque type which spreads across the tissue.
The tumors usually do not invade nervous tissue but only compress it, so that if they are removed early in their course there may be a resump- tion of normal neural function. They have an unusual property of spreading through bone and causing a marked hyperostosis, a process which is frequent with involvement of the outer one third of the sphenoidal ridge in the en-plaque type. In addition, the tumor tends to insinuate itself into the crevices, cracks, and foramina of the brainl and cranial cavity and to become very widespread.
Numerous pathologic classifications have been proposed for the tumor. Cushing and Eisenhardt (2), whose authoritative monograph is monumental in this field, trace it back to a primitive meningiocyte from that part of the ectoderm giving rise to cell masses on the neural groove and neural crest.
Thus, these tumors are particularly prone to occur near the large From the Department of Surgery (Ophthalmology), the University of Chicago.
* 298 Frank W. Newell and Thomas C. Beatnan venous lacunae of the skull about which arachnoid villi are clustered.
Arachnoid villi form the pacchionian bodies which perform functions similar to those of the retictuloendothelial apparatus in other parts of the body. T'hey have an active fibrocytic role in keeping the cerebro- spinal pathway cleared of debris and an imiiportant role in the forma- tion of new membranes associated with the reparative intracranial processes.
Globus (3) believes that cytologic studies of the meninges are unlikely to reveal the origin of the tumor, and he has directed attention to the phylogenetic and ontogenetic processes which take place in develop- ment of the meninges. He traced its origin to the mesenchyme which gives rise to the bone forming periosteum, the collagen-producing anlage of the dura, the anlage of the epithelial (endothelial or mesothelial) covering of the arachnoid, and the primordium of the pia.
Thus these tumors may present a variety of cell types, and it is not uncommon to find several cytologic types in different portions of the same tumor. Bailey and Bucy (4), in 1931, classified the tumor into mesenchymatous, angioblastic, meningioendotheliomatous, psammomatous, osteoblastic, fibroblastic, melanoblastic and lipomatous types.
Cushing and Eisenhardt presented nine types with variants within each group. Since then it has been recognized that the histologic origin plays a minimal role in prognosis.
Records of patients with histologically verified meningiomas seen at the University of Chicago Clinics are the basis of this report. Excluded from consideration were meningiomas involving the spinal cord and those tumors in which the diagnosis was not based on examination of the tissue. A total of 143 intracranial meningiomas are considered. The age distribution is shown in Table i. In this series the tumor caused TABLE 1. A(;E DISTRIBUTTION OF 143 CASES OF MENINGIOMA
Meningiomas of the tuberculum sellae arise from the meninigeal covering of the anterior and posterior clinoid processes and the floor of the sella. Their classic presenting signs are bitemporal constriction of the visual fields and unilateral optic atrophy occurring in the absence of demonstrable roentgenographic disease. Because of the intimate association of the optic chiasm with the area, tumors here may cause signs very early in their course. However, the region is crowded with important structures and with moderate increase in size, carotid arteries and cranial nerves are implicated so that remnoval constitutes a formilable and occasionally insurmountable surgical task.
There have been several recenit reviews of the ocular symptomology of meningiomnas of the tuberculum sellae, notably those of Grant and Hedges (7; reporting 30 cases) and Uihlein and WTeyand (8; reporting FrankJV.. Newiell and Tlhomiias C. Beainan1i.
'300 53 cases). Females were involved predomiinately, andl almost invariably loss of vision with an accompanying field defect was the outstanding symptom. The field defect was occasionially scotomatous, but usually peripheral, and was associated with an optic atrophy which was usually monocular but sometimes involved both eyes.
Although roentgenographic studies imiay indicate 11o abnormiality in the majority of instances, erosion of the clinoids, enlargement of the sella turcica, or a calcified tumor may be (lemonstrated. It must be emphasized that roentgenographic studies demonstrating a normnal skull when combined with optic atrophy by no means exclude the possibility of meningioma as a cause of the symptoms.
Fourteen patients were seen with meninigiom-la involving the tuberculum sellae. Of this number 5 were male and 9 wxvere female. The patients ranged in age from twenty-nin-e to fifty-eiglht years, witlh a median age of forty-two years. Their outstanding syni)tom was loss of vision involving one or both eyes, arising from priimary optic atrophy. Twelve of the 14 patients were seen initially by an ophthalmologist because of ocular symptoms.
Analysis of the field defect at the time the patient was first seen was complicated by the frequency with whiclh one eye was entirely blind before the patient sought care. A homnonymiious hemianiolpsia occurred in 3 patients and a bitemporal hemianopsia in 6 patienits. In 5 patients vision was so poor in one or both eyes that it could not be (leterminetl if the fieldl defect in the better eye rel)resentedl a heteronymous or homonymouLs type of involvement. In only one patient was the scotomatouis type of field defect found as (lescribed by Sclblezinger et al. (9).
This subsequently broke through to the periphery to be part of a superior temporal quadrantanopsia.
The extent to which visual defect had progressed in this group of patients when they were first seen is surprising. Eleven of the 14 patients had vision in one or the other eye of less than couinting fingers at 2 feet. One patient was blind in both eyes, and others had vision reduced to finger counting in each eye. Patients had notedl failing vision over a period of time ranging from six months to fouir years.
The optic atrophy seen in these patients, particularly when monocular, mtust be distinguishedl from that arising from vascular disease, glaucoma, an(d tabes. The patients were of an age grouip where their ocular symptoms might be attributed to glaucoma or a vascular accident involving the blood supply of the optic nerve or retina. The normnal size of the blood vessels in the optic atrophy associated with meningioma serves to distinguish it from atroplhy duie to vasctular occlusion.
301 Ocuilar Signs of Meningioma The intraocular pressure is normal and the progress of the field dlefect is imore rapid than that seen in glaucoma. Glaucoma provocative tests are, of course, negative in nmeningiomna. There are no other signs suggesting central nervous system syphilis or other inflammatory causes of optic atrophy. Two patients, both with advanced visual field defects, souight me(lical attention because of retrobulbar pain, although eacl had been aware of the visual disturbance prior to the onset of this pain.
Two other patients sought care because of (livergence of a blind eye, although the decreased vision had not apparently alarmedl them.
Two patients had amenorrhea of one year and two years' duration respectively, attributed to involvement of the pituitary gland. Other than this, the neurologic examination didl not contribtute to the diagnosis other than in regard to the ocular signs.
Roentgenograms were diagnostic or suggestive of the disease in 7 of the 14 patients. Findings included erosion or hyperostosis of the sella turcica, calcification in the tumor itself, (lisplacement of the pineal gland, and (lecalcification of the posterior clinoids. In 5 patients roentgenograms of the skull and optic foramen revealed no abnormality, but the tumor was diagnosed by means of contrast radiography.
In 2 patients in whom roentgenograms of the skull and optic foramen indicated no abnormnality, and angiography an(l pneumoencephalography were normal, a (lefinite (liagnosis was establishe(d only by craniotomy. The high index of suspicion necessary for early treatment of these patients is indicated in the following two case reports.
CASE REI'ORTS twenty-nine-year-ol(d Negro female was first seen December 1o, 1954, CASE i. A complaining of a decrease in vision in the left eye whiclh had first been noted ten months earlier. Examination indicated vision O.D. 20/30, corrected to 20/20; O.S. counting fingers at three feet, unimproved with correction. A marked left optic atrophy was present, an(l there was questionalble pallor of the right optic disc. Visual field examination in(licated a nasal island of vision remaining on the left side. The right visual field was normal. Roentgenograms of the skull and optic foramina and left carotidl angiography revealed no abnormnality. Neurologic examination was normal and, except for the optic atrophy, no other disease could be found. On December 24, 1954, a left frontal craniotomy was performed by Dr. Joseph P. Evans. A meningioma of the tuberculum sellae was found which encompassed both optic nerves. The tumor was resected with a minimal postoperative reaction and the patient was discharged two weeks later. When last examined in March, 1955, vision in the left eye was counting fingers at three feet. The right eye was normal. Histologic examination indicated a meningioendotheliomatous meningioma.
CASE 2. A fifty-seven-year-old white male farmer was first seen June 8, 1954, comp)laining of blurred vision for the previous six years.
Vision was O.D.
Frank W. Newell anrd Thomas C. Beamnan 302 finger countinig at one foot; O.S. 10/200, corrected to 20/30. Examination indicated temporal pallor of each disk, the right more marked than the left.
Visual field examination demonstrated an irregular contraction of the visual field of the right eye ancl a central scotoma of the left eye. Roentgenograms of the skull demonstrated no abnormality. A carotid angiogram and pneumoencephalogram indicated no intracranial disease. On August io, 1954, Dr.
Ralphl B. Cloward did a right frontal osteoplastic craniotomy and removed a meningioma the size of a tomato from the tuberculum sellae. A small berrylike aneurysm on the superior surface of the left carotid artery was an interesting additional patlhologic finding. When seen six months after operation, vision was corrected to O.D. 20/40, O.S. 20/20. The visual field was full in each eye.
The importance of comprehensive study of a patient presenting signs of optic atrophy even in the presence of normal roentgenograms cannot be overstated. When the visual loss is progressive, diagnosis may require craniotomy even when other neurologic signs are absent and intracranial disease cannot be demonstrated with roentgenograms or contrast studies.
MENINGIOM\AS OF THE SPHENOIDAL RII)GEKearns and Wagener (io) have recently reviewed the octular signs in io6 patients with meningioma of the sphenoidal ridge, of whom 73 presented a disturbance of the eyes as the only or one of the chief complaints. The sphenoidal ridge demarcates the frontal from the middle fossa of the skull and extends laterally from the anterior clinoid process to the pterional region of the cranial vault. It is composed of portions of both the greater and lesser wings of the sphenoid bone and is in intimate association with the orbit, the optic foramen, and the superior orbital fissure.
At the time of operation it may be difficult for the neurosurgeon to distinguish between tumors originating at the inner one third of the sphenoidal ridge and those arising from the tuberculum sellae or even the olfactory groove. Careful anamnesis and analysis of the ocular symptoms occurring early in the couirse of the tumor frequently will indicate the probable area of origin.
Cushing and Eisenhardt (2) found meningiomas of the deep clinoidal one third of the sphenoidal ridge to be characterized by unilateral failure of vision and primary optic atrophy. In 8 of 13 cases the eye was blind on admission; in 9 patients, proptosis was present. In 6 patients contralateral papilledema was present and in only 3 was the contralateral eye normal in all respects. Octulomotor palsies were present in the majority of their patients.
Tumors of the middle sphenoidal ridge may reach a large size withOciulai Nigns ol MVleningiona 303