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Show MRI IN OPHTHALMOPLEGIA 47 eral ophthalmoplegia which is a frequent clinical presentation in such cases. However, bilateral involvement associated with metastatic disease is a rare phenomenon. The common causes of acute bilateral ophthalmoplegia include myasthenia gravis, dysthyroid ophthalmopathy, pituitary apoplexy, vertebrobasilar insufficiency, botulinism, Fisher syndrome, and diabetic neuropathy ( 1). We have come across only two reports of metastasis causing acute bilateral ophthalmoplegia. A 59- year- old man with total bilateral ophthalmoplegia was found to have metastatic lung carcinoma to cavernous sinuses on autopsy ( 3). Another patient d e v e l o p e d acute bilateral o p h t h a l m o p l e g i a 2 weeks after right hemicolectomy for adenocarcinoma of colon. Final diagnosis on endoscopic sphenoidal biopsy revealed poorly differentiated adenocarcinoma ( 1). In our case also the patient was already suffering from adenocarcinoma of the prostate. One year later, he developed acute onset ocular motor nerve palsies bilaterally. MRI helped in prompt localization of the lesion and institution of radiotherapy giving palliation to the patient. Multiplanar MRI is more sensitive than computed tomography ( CT) for visualizing small lesions in this region, is better able to distinguish vascular from neoplastic lesions and has the potential to delineate intradural extension of the lesion. The relationship of the tumor to carotid artery and other major blood vessels can be best delineated by MRI ( 4). Relaxation characteristics and most morphologic features are nonspecific. Tumor invasion of basisphenoid and basiocciput with replacement of fatty bone marrow by neoplastic tissue causes a lowering of signal intensity on Tl-weighted images. The usual signal on T2- weighted images is hyperintense. However, a low- signal intensity on T2- weighted images, as in our case, is occasionally encountered in markedly sclerotic metastasis ( 5). The other condition which can cause a hypoin-tense signal on T2- weighted images is fungal infection. However, extensive bone involvement, as seen in our case, is unusual in fungal lesions ( 6). Our case highlights an unusual clinical and radiological presentation of extra- axial intracranial prostatic metastasis. The prompt recognition of this rare occurrence by maintaining a high index of suspicion can enable the patient to receive treatment that may improve quality of his life. REFERENCES 1. Supler ML, Friedman WA. Acute bilateral ophthalmoplegia secondary to cavernous sinus metastasis: a case report. Neurosurgery 1992; 31: 783- 6. 2. Atlas SW. Adult supratentorial tumors. Sem'm Roentgenol 1990; 25: 130- 54. 3. Mills RP, Insalaco SJ, Joseph A. Bilateral cavernous sinus metastasis and ophthalmoplegia. / Neurosurg 1981; 55: 463- 6. 4. Hirsch W Jr, Hryshko FG, Sekhar LN, Brunberg J. Comparison of MR imaging, CT and angiography in the evaluation of the enlarged cavernous sinus. AJR 1988; 151: 1015- 23. 5. Atlas SW Jr. Magnetic resonance imaging of the brain and spine. New York: Raven Press; 1991: 945. 6. Breen DJ, Clifton AG, Wilkins P, et al. Invasive aspergillo-ma of the skull base. Neuroradiology 1993; 35: 216- 17. EDITORIAL COMMENT The paper by Dr. Agarwal and colleagues presents a very interesting and unusual presentation in a 57- year-old man with known prostate cancer for 1 year, who suddenly developed a bilateral total ophthalmoplegia. A magnetic resonance scan revealed a large mass lesion involving the clivus and both cavernous sinuses. The patient was treated with 4,000 cGy of radiotherapy over the next 4 weeks. Toward the end of that therapy, some improvement of ocular motility occurred in the right eye, but with no response on the left. It was stated that the patient had been treated with bilateral orchiectomy 1 year prior to onset of his ocular problem. However, the paper does not state whether or not the patient was treated with TACE ( chlorotrianisine) at the time of onset of his ophthalmoplegia. We have seen such dramatic responses to orbital metastases of prostate carcinoma to TACE that it was thought reasonable to add this brief editorial comment to this paper. If the patient is still alive and having problems, I would suggest that the authors administer TACE 25 mg per day by mouth for a short period and see how he responds. This therapy is also recommended to the reader who might be encountering a patient with metastatic prostate carcinoma, particularly involving the orbit and/ or cranium. J. Lawton Smith, M. D. / Neuro- Ophthalmol, Vol. 15, No. 1, 1995 |