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Show Journal of Neuro- Ophthalmology 18( 1): 47- 48, 1998. © 1998 Lippincoll- Ravcn Publishers, Philadelphia Terminating Attacks of Ocular Neuromyotonia Avinoam B. Safran, M. D., and Michel Magistris, M. D. We examined a 30- year- old woman who, for 6 months, had suffered from ocular neuromyotonia, which consisted of episodic ocular depression. Apart from the ocular complaint, her medical history and the clinical findings were unremarkable. The patient discovered that she could terminate each episode of tonic ocular depression instantly by forcefully directing her gaze upward. Stretching the affected muscle might also prove to be an effective way of ending attacks of neuromyotonia in other patients suffering from this condition. Key Word: Ocular neuromyotonia- strabismus. Ocular neuromyotonia has been defined as a paroxysmal monocular deviation resulting from spasm of eye muscles ( 1,2). We report here our observation of a patient suffering from ocular neuromyotonia who found a way of instantly terminating each episode of tonic ocular deviation. CASE REPORT This 30- year- old woman complained of intermittent diplopia that had begun insidiously 6 months previously. The episodes lasted for about 30 s to 3 min. Diplopia was mainly vertical. Apart from the these complaints, the patient's medical history was unremarkable. On examination, the her visual acuity and visual fields were normal, as were findings on biomicroscopy of the globes and fundi. Her pupils were equal in light and darkness, and reacted well to photic and accommodative stimulation. Her left upper eyelid showed slight ptosis, but no oculomotor synkinesis on gazing down and/ or to the right. During the examination, at intervals of 2- 5 min, her left eye showed a slowly progressive depression that increased over ~ Vz min. Her pupils were unaffected. During these episodes, she reported a pulling sensation in her left orbit. Tonic deviation of the eye was induced by excentric gaze in any direction, including upward. We Manuscript accepted 8/ 27/ 97. From the Neuro- Ophthalmology Unit, Ophthalmology Clinic ( A. B. S.); and Electroneuromyography Unit, Neurology Clinic ( M. M.), Department of Clinical Neurosciences, Geneva University Hospital, Geneva, Switzerland. Address correspondence and reprint requests to Dr. A. B. Safran, Neuro- Ophthalmology Unit, Ophthalmology Clinic, Geneva University Hospitals, CH- 1211 Geneva 14, Switzerland. observed that she could end the tonic depression of her left eye by forcefully gazing upward for a few seconds. After sustained convergence, relaxation of adduction in the left eye was markedly slowed, a condition that was associated with a slight pulling sensation in the left orbit. Between attacks, motility was normal. Rapid horizontal or vertical saccades, or moderate convergence, did not elicit unusual ocular motor phenomena. The results of neurological assessment, electro-neuromyographic evaluation, routine blood tests, and cerebral and orbital magnetic resonance imaging were all normal. Carbamazepine therapy was started at a dose of 200 mg daily progressively increasing to 200 mg three times a day. No improvement was noted, however, and the treatment was stopped after 2 months. The disorder progressively disappeared within a month, but it recurred 1 year later. DISCUSSION Our patient showed characteristic signs of ocular neuromyotonia involving muscles innervated by the left third cranial nerve. The condition consisted of episodic apparently tonic contraction of the left inferior rectus muscle, and delayed relaxation of the left rectus internus muscle, following sustained convergence. A third muscle innervated by the left third cranial nerve- the levator palpebrae muscle- showed moderate limitation, a phenomenon already described with this disorder ( 2). By 1997, a total of 25 patients with ocular neuromyotonia had been reported in the literature ( 3): 13 had a history of a tumor at the base of the skull and most had undergone radiation therapy ( 4). In other observations, the ocular condition was associated with Graves' ophthalmopathy ( 3) or with carotid artery aneurysm ( 5). Our patient belonged to the uncommon category of patients suffering from ocular neuromyotonia who do not have a known medical history of such disorders ( 4). It is of interest that our patient could terminate attacks of sustained tonic contraction of the inferior rectus muscle by forcefully directing her gaze upward, thereby attempting to elongate the affected muscle. Both in normal subjects and in patients with lesions in peripheral motor nerves, muscular cramps are characteristically enhanced by muscle shortening and released by muscle 47 48 A. B. SAFRAN AND M. MAGISTRIS elongation ( 6- 8). This phenomenon may be similar to that observed in our patient when she attempted to end episodes of sustained contraction. It is uncertain whether all such patients can terminate attacks of neuromyotonia by using this technique. The procedure may, however, prove useful in a number of patients affected by the condition. REFERENCES 1. Lessell S, Lessell 1M, Rizzo JF. Ocular neuromyotonia after radiation therapy. Am J Ophthalmol 1986; 102: 766- 70. 2. Shults WT, Hoyt WF, Behrens M, MacLean J, Saul RF, Corbett JJ. Ocular neuromyotonia: a clinical description of six patients. Arch Ophthalmol 1986; 104: 1028- 34. 3. Chung SM, Lee GL, Holds JB, Roper- Hall G, Cruz OA. Ocular neuromyotonia in Graves' dysthyroid orbitopathy. Arch Ophthalmol 1997; 115: 365- 70. 4. Frohman EM, Zee DS. Ocular neuromyotonia: clinical features, physiological mechanisms, and response to therapy. Ann Neurol 1995; 37: 620- 6. 5. Ezra E, Spalton D, Sanders MD, Graham EM, Plant GT. Ocular neuromyotonia. Br J Ophthalmol 1996; 80: 350- 5. 6. Norris FH, Gasteiger EL, Chatfield PO. An electromyographic study of induced and spontaneous muscle cramps. Electroencepha-logr Clin Neurophysiol 1957; 9: 139- 47. 7. Roth G, Magistris RR, Le Fort D, Desjacques P, Delia Santa D. Plexopathie brachiale post- radique, blocs de conduction persistants, decharges myokymiques et crampes. Rev Neurol ( Paris) 1988; 144: 173- 80. 8. Bertolasi L, De Grandis D, Bongiovanni LG, Zanette GP, Gas-perini M. The influence of muscular lengthening on cramps. Ann Neurol 1993; 33: 176- 80. J Neum- Ophthalnwl, Vol. 18, No. 1, 1998 Journal of Neuro- Ophthalmology 18( 1): 49- 52, 1998. © 1998 Lippincolt- Raven Publishers, Philadelphia Papilledema in a Man with an " Occult" Dural Arteriovenous Malformation Timothy J. Martin, M. D., D. Antonio Bell, M. D., John A. Wilson, M. D. CASE REPORT A 51- year- old man was evaluated in November 1994 for transient visual obscurations for 2 months. In addition, he reported hearing his " heartbeat" in both ears. He denied headache, vitamin use, recent trauma, or recent weight gain or loss. Visual acuity was 20/ 15 in each eye, with no relative afferent pupillary defect, normal motility, and normal slit- lamp examination results. Automated perimetry showed mild enlargement of the blind af> ( Si • ' & * " a * " - ( * M £ H ) h- jjjggj- j " < 5> * t! i) t!) ^ fclTr MO * 87 ( JB P < 2X CPSO' 000 < fB left eye FW* tonLocn>: 0/ 17 F t fM POSEim.; 0 / 5 F « S* tea Enors. o/ e TniOurMwv 08.53 I ' M ) 31 dO B right eye ( II) ( W> ' • & " " • & » " a » » » » - A-** £- a • " » * ft » > ti^- fe^ 4^> » „ 1F W> 2 1 5 ( 6 P30 3 8 * dB P< 5X S- 193 tfB 0> SP: 3, ia 00 P< ZX Fk4tOoLot » *. i / 1B rusePOSCrtMtrl/ tl Tot CwMttv 0909 » • » & * hg-& " f » left eye FIG. 1. Humphrey automated 30- 2 perimetry. $ - » =, e I a K x c P » . « . I 9 03 " < 5X right eye Manuscript received April 25, 1997; accepted July 25, 1997. From the Departments of Ophthalmology ( T. J. M.), Radiology ( D. A. B.), and Neurosurgery ( J. A. W.), Bowman Gray School of MedicineAVake Forest University, Winston- Salem, North Carolina, U. S. A. Address correspondence and reprint requests to Dr. Timothy J. Martin, Wake Forest University Eye Center, Medical Center Boulevard, Winston- Salem, NC 27157- 1033, U. S. A. Presented as a poster at the North American Neuro- Ophthalmology Society meeting in Keystone, Colorado, February 10, 1997. 49 50 T. J. MARTIN ET AL. spots and scattered threshold loss in the inferior nasal quadrants ( Fig. 1A). Bilateral diffuse optic disk edema was present ( Fig. 2A). Enhanced magnetic resonance imaging ( MRI) of the brain was read as normal. A lumbar puncture showed an opening pressure of 300 mm of water with normal cerebrospinal fluid ( CSF). Acetazol-amide ( 500 mg twice a day) was started. By March 1995 the patient noted increased intensity of the pulsatile tinnitus. The examination was unchanged except that a cranial bruit could now be auscultated over the left retroauricular area. Cerebral angiography confirmed the presence of a suspected dural arteriovenous malformation ( DAVM) in the region of the left transverse sinus ( Fig. 3). In retrospect, evidence of the DAVM could be identified on the original MRI ( Fig. 4). Transarterial particulate embolization was performed and resulted in rapid abatement of the patient's symptoms. Acetazolamide was discontinued. In May the patient's pulsatile tinnitus returned, although it was less prominent. The visual fields suggested improvement ( Fig. IB), but the papilledema was only minimally improved ( Fig. 2B). Opening pressure on lumber puncture was 410 mm of water. Angiography was repeated in July, showing recanali-zation of the DAVM and occlusion of the left sigmoid sinus at the skull base ( Fig. 5). Venous pressures in the superior sagittal sinus ( SSS) and left transverse sinus were markedly elevated ( 33 mmHg in the left transverse sinus; 26 mmHg in the SSS). Transarterial embolization of the DAVM with acrylic glue was performed with incomplete closure and only temporary relief of symptoms. The pulsatile tinnitus recurred in November, and an- /" right \ November. V 7 left , Pf f% • • • > * l e r t^ FIG. 2. Optic disk appearance. ./ Neum- Ophlhalmol, Vol. 18, No. 1, 1998 OCCULT DURAL ARTERIOVENOUS MALFORMATION 51 r J FIG. 3. Angiography ( lateral projection of common carotid artery injection) shows the DAVM ( arrows), fed by numerous branches of the external carotid artery, and meningeal branches of the internal carotid artery. giography identified persistent feeding arteries. A trans-venous approach allowed successful closure of the left transverse and sigmoid sinuses with multiple fibered platinum coils ( Fig. 6). Within 2 months there was clear FIG. 4. Axial MRI. The MRI was initially interpreted as normal. In retrospect, the irregular contour and flow voids in the left transverse sinus reflect the presence of the DAVM ( arrows). * W^ T J . k ^ i Ik / V6i FIG. 5. Angiography ( left internal jugular injection) shows inability to inject contrast beyond the skull base ( arrow), demonstrating sigmoid sinus occlusion. improvement in the patient's optic disk edema ( Fig. 1C), and the patient has remained asymptomatic for over a year. DISCUSSION The syndrome of idiopathic intracranial hypertension in obese women is a well- described primary entity. However, in men with papilledema, a diligent search for an identifiable cause must be pursued. MRI alone may not be sensitive enough to visualize DAVMs ( 1). It is unknown whether magnetic resonance angiography and venography ( MRA and MRV) would have been diagnostic in this case, because auscultation of an intracranial bruit r FIG. 6. Angiography ( lateral projection of common carotid artery injection) shows coils in the sigmoid and transverse sinuses ( arrows) and successful closure of the DAVM. J Neuro- Ophlhalmol, Vol. IS, No. I, 1998 52 T. J. MARTIN ETAL. led directly to cerebral angiography. The possibility of a dural sinus abnormality suggests that it is reasonable to include MRA and MRV sequences with the initial MRI evaluation of men with papilledema ( and women with atypical presentations). However, angiography remains the standard and must be pursued when clinically indicated, even with normal noninvasive imaging ( 1- 3). Acknowledgment: Photographs and images were prepared by Richard E. Hackel, M. A., C. R. A. REFERENCES 1. Bianchi- Marzoli S, Righi C, Brancato R, et al. Pseudotumor cerebri in men: the need for cerebral angiography. In the proceedings of the North American Neuro- ophthalmology Society Durango, Colorado, 1994. 2. Halbach VV, Higashida RT, Hieshima GB, et al. Dural fistulas involving the transverse and sigmoid sinuses: results of treatment in 28 patients. Radiology 1987; 163: 443- 7. 3. Kupersmith, MJ. Neuro- ophthalmic manifestations of intracranial dural venous disorders. In: Kupersmith MJ, ed. Neuro- vascular Neuro- ophthalmology. Berlin: Springer- Verlag, 1993. J Neiiro- Ophthalinol, Vol. IS, No. 1, 1998 |