Symposium: Tumors of the Lids and Orbit f f f

ORBITAL TUMOR EVALUATION

ALLEN M. PuTTERMAN, MD CHICAGO, ILLINOIS

The key tests in the evaluation of orbital pathology-orbital roentgeno­grams, cr scans, and ultrasonography­are defined.

THE evaluation of orbital pathol­ogy has greatly changed since the introduction of the computerized axial tomography (CAT) scan. Or­bital scans, thermography, and or­bitography have essentially been deleted, and the need for orbital venography and arteriography has been greatly decreased. The key tests are now orbital roentgeno­grams, CAT scans, and ultrasonog­raphy; however, their overlapping roles need definition.

The CAT scan demonstrates the same orbital bones as conventional and tomographic orbital roentgeno­grams, but the pathology of the bony portion of the orbit is better defined with the roentgenograms (Fig 1 and 2). B-scan ultrasonog­raphy, as well as the CAT scan, depicts the size and location of orbital masses, but the mass is usually better visualized with a CAT scan (Fig 3 and 4). This raises

Submitted for publication Oct 25, 1978.

From the University of Illinois Eye and Ear In­firmary and Michael Reese Hospital and Medical Center, Chicago.

Presented in combination with the American So­ciety of Ophthalmic Plastic and Reconstructive Surgery at the 1978 Annual Meeting of the Ameri­can Academy of Ophthalmology, Kansas City, Mo, Oct 22-26.

Reprint requests to 111 N Wabash Ave, Chicago, IL 60612.

Fig 1.-Computerized axial tomogram of patient with downward displacement of left eye secondary to fracture of orbital roof.

doubts as to the need for B-scan ultrasonography in the evaluation of orbital tumors. A-scan ultra­sonography can indicate the prob­able diagnosis with more accuracy than CAT scans but not with the almost 100% diagnostic potential of the microscopic tissue study of bi­opsy specimens (Fig 5 and 6).1 It is therefore questionable whether A­scan ultrasonography is necessary when the tumor is easily accessible to biopsy.

In the author's experience, the CAT scan usually does not demon­strate a tumor in patients with

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872 ALLEN M. PUTTERMAN OPHTH AAO

Fig 2.-Tomographic roentgenogram of left orbit of patient in Fig 1. Fracture fragments are better visualized on roentgenograms compared with com­puterized axial tomography.

Fig 3.-Posterior orbital mass easily visualized on computerized axial tomography, which turned out to be orbital hemangioma on surgical exploration.

Fig 4.-B-scan ultrasonography ofpatiept in Fig 3, which failed to demonstrate orbital tumor.

Fig 5.-A-scan ultrasonography demonstrating probable diagnosis of optic nerve meningioma.

palpable orbital tumors who do not have displacement of the eye (Fig 7 and 8). However, in patients that have displacement of the eye, the CAT scan invariably demonstrates the presence of a tumor (Fig 9 and 10).

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Fig 6.-Biopsy specimen of patient in Fig 5, in which microscopic tissue evaluation demonstrated definite diagnosis of optic nerve meningioma (he­matoxylin-eosin, x50).

Fig 7.-Patient with left anterosuperior nasal pal­pable orbital tumor with no ocular displacement.

Fig 8.-Normal computerized axial tomography scan of patient in Fig 7. Diagnosis was benign lymphoid hyperplasia on evaluation of biopsy spe­cimen.

Fig 9.-Patient with anterosuperior palpable or­bital tumor with downward and outward displace­ment of right eye.

Fig 10.-Computerized axial tomography scan with visualized right orbital tumor. Diagnosis of neurofibromatosis was made on evaluation of biopsy tissue.

The observations noted in the preceding paragraphs have led to the following conclusions and rec­ommendations: (1) If the tumor is anterior and palpable and the eye is not displaced, conventional and tomographic orbital roentgenograms are ordered and a biopsy is per­formed. (2) If the tumor is anterior and palpable and the eye is dis­placed, conventional and tomo­graphic orbital roentgenograms plus CAT scans are evaluated and then a biopsy of the tumor is made. (3) If the tumor is posterior and not palpable and the eye is displaced in patients with normal thyroid

874 ALLEN M. PUTTERMAN OPHTH AAO

evaluation, conventional, tomo­graphic, and optic canal x-ray films as well as CAT scan and A-scan ultrasonography are obtained. Then, if an inflammatory tumor is diag­nosed, a trial regimen of systemic corticosteroids is indica ted. If a malignant tumor is diagnosed, a systemic workup is done to look for a primary or metastatic tumor. Or­bital surgery or observation then follows, depending on the clinical and diagnostic results.

DISCUSSION

Invention of new diagnostic tools in the evaluation of orbital pa­thology has greatly enhanced the treatment of orbital tumors but has also caused confusion in orbital evaluation. The role of the CAT scan continually changes with new generations of machines and with increased experience in evaluating data from these scans. Moreover, the person who evaluates the CAT scans and chooses the sections to study greatly influences the diag­nostic potential of this modality.

The need to preserve the clinical judgment of the physician must not be lost in the mechanical study of the patient with a suspected or­bital tumor. The diagnosis arrived at after a thorough history is taken and an ocular examination is made can still lead to the most accurate steps in evaluating and treating the patient. For example, the pa­tient with unilateral proptosis, with­out visual loss and without a pal­pable tumor, who also has lid re­traction and diplopia secondary to inferior rectus restriction most likely ha!:f thyroid ophthalmopathy. The workup of such a patient should start with a 24-hour radioactive iodine uptake test before and after

sodium liothyronine (Cytomel) ad­ministration and not with x-ray films, CAT scans, and ultrasonog­raphy.

A recent article (Chicago Sun­Times, July 23, 1978) further em­phasizes the importance of the clinical judgment of the physician. Following is an excerpt from the article:

Last year American doctors performed five billion laboratory tests at a cost of $11 billion, or 25 tests for every man, woman, and child in the country at an average cost of $55 per person. Is it necessary and can we afford it? Is our heavy reliance on medical machines reducing the clinical skills of to­day's physicians? Is our uncritical accep­tance and promotion of these devices lead­ing the public, patients, and physicians to expect too much from medicine and thereby to demand too little of themselves?

Until CAT scan results can be thoroughly investigated, A-scan ul­trasonography, conventional tomo­graphic and optic canal roentgeno­grams, and CAT scans are recom­mended for the majority of patients with unilateral exophthalmos who have normal thyroid test results. Orbital venography and arteriog­raphy can be added if certain vas­cular abnormalities are suspected.

SUMMARY

The evaluation of orbital pa­thology has greatly changed since the introduction of computerized axial tomography (CAT) scans. Un­til CAT scan results can be more thoroughly investigated, A-scan ul­trasonography, conventional tomo­graphic and optic canal roentgeno­grams, and CAT scans in combina­tion are the key tests in evaluating patients with unilateral exophthal­mos who have normal thyroid test results.

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The need to preserve the clinical judgment of the physician must not be lost in the mechanized study of a patient with a suspected orbital tumor. The diagnosis arrived at by a thorough history and physical examination can still lead to the

most accurate steps in evaluating and treating the patient.

REFERENCE 1. Hodes BL, Weinberg P: A combined

approach for the diagnosis of orbital dis­ease: Computed tomography and standard­ized A-scan echography. Arch Ophthalmol 95:781-788, 1977.