Journal of Neuro-Ophthalmology, December 1985, Volume 5, Issue 4

One-and-a-half syndrome in a patient with metastatic breast disease.

This report reviews the clinical course of a patient with breast carcinoma presenting with the classic one-and-a-half syndrome. She had no saccades to the left and no leftward eye deviation on oculocephalic movement. Her clinical examination suggested involvement in the medial longitudinal fasciculus, paramedian pontine reticular formation, and abducens nucleus. There has only been one previous case reported of a metastasis producing this syndrome. A computed tomography scan confirmed the pontine location of the lesion.

J. Clin. Neuro-ophthamol. 5:270-272, 1985 © 1985 Raven Press, New York One-and-a-Half Syndrome in a Patient with Metastatic Breast Disease EDGARDO A. CRISOSTOMO, M.D. Abstract This report reviews the clinical course of a patient with breast carcinoma presenting with the classic one-and-a-half syndrome. She had no saccades to the left and no leftward eye deviation on oculo­cephalic movement. Her clinical examination sug­gested involvement in the medial longitudinal fas­ciculus, paramedian pontine reticular formation, and abducens nucleus. There has only been one previous case reported of a metastasis producing this syndrome. A computed tomography scan con­firmed the pontine location of the lesion. The one-and-a-half syndrome consists of an ipsilateral gaze palsy or paresis accompanied by an internuclear ophthalmoplegia on contralat­eral gaze, secondary to a unilateral lesion of the pontine tegmentum. Etiologic considerations for this syndrome include infarct,1,2 demyelin­ating disease,1,2 hemorrhage,3 neoplasm,4 an­gioma, S and aneurysm. 1 The first two causes comprise the majority of the general clinical ex­perience. I A metastasis can conceivably pro­duce the syndrome, but only one case has been reported thus far. 2 Recently we had the oppor­tunity to observe the syndrome in a patient with metastatic breast disease. A cranial computed tomography (CT) scan demonstrated the lesion. Case Report A 50-year-old, right-handed, Caucasian woman presented to us on August 10, 1983, for nausea, vomiting, and inability to void. Four­and- a-half years previously, she had undergone a radical mastectomy for adenocarcinoma of her right breast. A year prior to her admission to From the Department of Neurology, Albany Medical Center Hospital, Albany, NY U.S.A. Present address: Neurology Research Laboratory, V.A. Hospital, Duke University Med­ical Center, Durham, NC 27705, U.S.A. Write for reprints to: E. A. Crisostomo, M.D., Neurology Research Laboratory, Duke University Medical Center, Durham, NC 27705, U.S.A. 270 our hospital, she presented with evidence of bone and liver metastases. Five weeks before she came to our attention, she was admitted to a local hospital for horizontal diplopia on bilat­eral conjugate gaze, and right-.sided hemip~res­thesia. A cranial CT scan obtamed at that time, as well as a spinal fluid analysis, were reported as normal. She had no history of hypertension or diabetes mellitus. On the day of her admission to our hospital, her vital signs were normal except for a low­grade fever. The neurological examination dis­closed no higher cognitive dysfunction. Her optic discs were flat. The left corneal reflex was slightly diminished. A left "peripheral" facial palsy was present. She was dysarthric and her gag reflexes were depressed. Nociception, pro­prioception, and light touch and vibration sen­sations were all reduced on her right side except for the face, which was normal. In addition she had a right hemiparesis. The muscle stretch re­flexes were hyperactive on the right, and her toe responses were extensor. No limb ataxia was detected. Her pupils measured 3 mm and were equal and bilaterally reactive to light. The left eye had a mild exotropia, and remained fixed with any type and direction of lateral movements. A pa­ralysis of left conjugate gaze was evident. At the same time, her right eye displayed a horizontal jerk nystagmus on right gaze. No saccades could be elicited voluntarily to the left. With horizontal optokinetic strip stimulation, the right eye showed nystagmus to the right but none to the left. The left eye remained fixed. Vestibular stimulation with cold water calories failed to move the eyes past the midline to the left, but the right eye had a right-beating nys­tagmus. Oculocephalic stimulation could only bring the right eye to the ipsilateral extreme. Convergence and vertical eye movements were possible. Initial laboratory results showed elevated liver enzymes and mild thrombocytopenia (84,OOO/mm3). The rest of her hematologic, bleeding, and coagulation studies were unre­markable. A CT scan showed a hyperdense le- Journal of Clinical Neuro-ophthalmology I Figure 1. This unenhanced CT scan shows a hyperdense lesion (arrows) more to the left at the level of the caudal pons. sion in the left paramedian tegmentum at the level of the caudal pons (Fig. 1). She was given platelet transfusion and dexa­methasone (Decadron). She remained febrile, however, and progressively became tachypneic and obtunded. She died on the sixth hospital day. No autopsy study was performed. Discussion This patient's neurological examination was compatible with a lesion at the level of the pons. The lateral gaze palsy probably involved a le­sion of both abducens nucleus and paramedian pontine reticular formation (PPRF). Clinically, involvement of the left abducens nucleus was suggested by a complete left gaze palsy without preservation of ipsilateral deviation on orulo­cephalic maneuver.2•6•7 The loss of reflex vestib­ular movement signified an abducens nucleus pathology. Lastly, the ipsilateral "peripheral" facial palsy further suggested that the lesion was at the level of the abducens nucleus. 8 Al­though the functional role of the PPRF in pur­suit movements remains unclear, human patho­logic data have indicated that this formation is involved when all ipsilateral saccades are abol­ished. v The impairment of medial gaze of the left eye resulted from the lesion's interruption. of the medial longitudinal fasciculus. The mechanism of the abduction nrstagmus in the right eye is still unresolved.9-1 The historical course of this patient favored a metastasis as the lesion producing the one-and­a- half syndrome. A primary pontine hemor­rhage was unlikely because of the progressive course, absence of hypertension, and the lack of pupillary constriction or coma.3 A pathologic December 1985 Crisostomo study of the distribution of metastatic nodules in the brain parenchyma has revealed that less than 1% of the lesions involved the pons. 12 Since no autopsy was done on this patient, there was no confirmation that a single metas­tasis was involved, a rare finding indeed. 12,13 It is possible more lesions would have been found. The discreteness of the lesion required to produce the syndrome, in addition to the rel­ative infrequency of metastases to the pons, may explain its rarity in the clinical literature. The only other case known to us is that of a metastatic melanoma in a patient who, in con­trast to the present case, manifested a disso­ciated conjugate gaze palsy ipsilateral to the le­sion. 2 A case of a metastatic bronchogenic car­cinoma to the pons had an extended syndrome involving defective abduction of the opposite eye.6 Because this syndrome's constellation of signs are sufficiently localizing, its recognition at the bedside will greatly facilitate its early di­agnosis. This is especially important when ther­apeutic modalities are available or at least being considered. References 1. WaU, M., and Wray, S. H.: The one-and-a-half syndrome-a unilateral disorder of the pontine tegmentum: A study of 20 cases and review of the literature. Neurology (Cleveland) 33: 971-980, 1983. 2. Pierrot-Deseilligny, C, Chain, F., Serdaru, M., and Lhermitte, F.: The "one-and-a-half" syn­drome. Electro-oculographic analyses of five cases with deductions about the physiological mechanisms of lateral gaze. Brain 104: 665-699, 1981. 3. Caplan, L. R., and Goodwin, J. A.: Lateral teg­mental brainstem hemorrhages. Neurology (NY) 32: 252-260, 1982. 4. Enoksson, P.: Internuclear ophthalmoplegia and paralysis of horizontal gaze. Acta Ophthalmo/. (Co­penh.) 43: 697-707, 1965. 5. Sharpe, J. A., Rosenberg, M. A., Hoyt, W. F., and Daroff, R. B.: Paralytic pontine exotropia: A sign of acute unilateral pontine gaze palsy and internuclear ophthalmoplegia. Neurology (Min­neap.) 24: 1076-1081,1974. 6. Pierrot-Deseilligny, C, Goasguen, J., Chain, F., and Lapresle, J.: Pontine metastasis with disso­ciated bilateral horizontal gaze paralysis. J. Neural. Nel/rosl/rg. Psychiatry 47: 159-164, 1984. 7. Bogousslavsky, J., Miklossy, J., Regli, F., Deruaz, J. P., and Despland, P. A.: One-and-a-half syn­drome in ischaemic locked-in state: A clinico­pathologic study. J. Nellrol. Nel/rosllrg. Psychiatry 47: 927-935, 1984. 8. Oomen, K. J., Smith, M. S., and Labadie, E. L.: 271 One-and-a-Half Syndrome Pontine hemorrhages causing Fisher one-and-a­half syndrome with facial paralysis. f. Clin. Nt'lIro-ol'lIthallllol. 2: 129-132, 1982. 9. rola, j., and Robinson, D. A.: An explanation of eye movements seen in internuclear ophthal­moplegia. Arch. Nl'lIrol. 33: 447-452, 1976. 10. Bender, M. B.: Brain control of conjugate hori­zontal and vertical eye movements. A survey of the structural and functional correlates. Brain 104: 665-699, 1981. 272 11. Baloh, R. W., Yee, R. D., and Honrubia, V.: In· ternuclear ophthalmoplegia. I. Saccades and dis­sociated nystagmus. Arch. Neurol. 35: 484-489, 1978. 12. Takakura, K., Sano, K., Hojo, S., and Hirano, A.: Metastatic tumors of the central nervous system. New York: Igaku-Shoin, 1982:24-36. 13. Weiss, H. D., and Richardson, Jr., E. P.: Solitary brainstem metastases. Neurology (NY) 28: 562­566, 1978. Journal of Clinical Neuro-ophthalmology