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Show 280 LETTERS TO THE EDITOR Fluorescein angiogram showed bilateral disk leakage suggestive of disk edema, without autofluorescence. In addition, the presence of drusen was ruled out by normal orbital echography. Cerebral angiography ruled out cerebral venous thrombosis and dural fistula. She was discharged on acetazolamide ( 750 mg/ day). Three weeks later, bilateral tinnitus and transient visual loss recurred, whereas the post- lumbar puncture headache resolved. Lumbar puncture was then repeated and showed an opening pressure of 155 mm H20 and normal CSF. Again, although tinnitus and transient visual obscurations resolved within a few hours, the patient complained of severe postural headache that were treated with a blood patch after 2 days. Tinnitus recurred after the blood patch. After 2 years of follow- up, the patient is still treated with acetazolamide and is still complaining of tinnitus, intermittent transient visual obscurations, and moderate headache. Her visual acuity is still normal, and the fundus shows less severe, but persistent, bilateral disk edema. Repeated Goldmann and Humphrey 30- 2 visual fields are stable. We initially planned to perform an optic nerve sheath fenestration in the left eye, but this procedure was not performed because her visual function remained stable. The findings of a bilateral disk edema associated with transient visual obscurations, tinnitus, and headache with normal neurologic examination, neuroimaging, and CSF is suggestive of PTC. However, as in the case reported by Green et al. ( 1), our patient has a " normal intracranial pressure." We did not perform 48- h continuous subarachnoid ICP monitoring, but the opening pressure was ' ' normal'' on two separate measurements and our patient experienced low- pressure headache after the three lumbar punctures, suggesting that the CSF pressure was previously not elevated. As in the case reported by Green et al. ( 1), the presence of nonvisual symptoms that resolved with lumbar punctures ( i. e., tinnitus and fullness of the head) suggests that our patient represents a variation of PTC that has been called " normal pressure PTC" by Jonhnston et al. ( 2). Valerie Biousse, M. D. Marie Germaine Bousser, M. D. Department of Neurology Hopital Saint- Antoine Monique Schaison, M. D. Hopital Pitie- Salpetriere Paris, France REFERENCES 1. Green JP, Newman NJ, Stowe ZN, Nemeroff CB. " Normal pressure" pseudotumor cerebri. J Neuroophthalmol 1996; 16: 196- 8. 2. Johnston I, Hawke S, Halmagyi M, Teo C. The pseudotumor syndrome: disorders of cerebrospinal fluid circulation causing intracranial hypertension without ventriculomegaly. Arch Neurol 1991; 48: 740- 7. Normal Pressure Pseudotumor Cerebri To the Editor: Biousse and colleagues describe a woman with clinical symptoms and signs consistent with a diagnosis of pseudotumor cerebri ( PTC) without intracranial pressure elevation as defined by standard norms and as measured on two lumbar punctures. This case would constitute the third such reported patient with ' ' normal pressure PTC' ( 1,2). These three patients all had improvement of visual function and relief of other symptoms of classic PTC when intracranial pressure ( ICP)- lowering procedures were performed. As we were careful to note in our original case report ( 2), single measurements of ICP can miss pressure " peaks." Although continuous 48- h subarachnoid ICP monitoring may seem aggressive, it may still be appropriate in the evaluation of these very atypical presentations of PTC, especially if invasive intervention is contemplated. The monitoring may allow for complete fulfillment of the Dandy criteria and provide diagnostic as well as medicolegal support. If no elevated pressures are noted, the monitoring could be continued after surgical intervention, as in our case, to gauge the postoperative effect on ICP. We caution physicians to not make the diagnosis of " normal pressure PTC" too freely. It would be unfortunate if a patient with anomalous disks and headaches received an optic nerve sheath fenestration. We believe that if a patient presents with a clinical picture indicative of PTC, without evidence of ICP elevation on two separate lumbar punctures, more aggressive evaluation is needed. Serial visual fields, frequent fundoscopy with optic nerve photographs, and subjective evaluation of headaches as related to lumbar punctures should all be included in the diagnostic evaluation. Fluorescein angiography and optic nerve ultrasound should also be considered. Eventually, as more physicians become aware of this atypical presentation of PTC, new diagnostic criteria may be added to the Dandy criteria. We are grateful to Biousse et al. for sharing another case of this interesting and diagnostically challenging presentation of PTC. Jeffrey Paul Green, M. D. Nancy J. Newman, M. D. Emory University School of Medicine Atlanta, Georgia, U. S. A. REFERENCES 1. Johnston I, Hawke S, Halmagyi GM, Teo C. The pseudotumor syndrome: disorders of cerebrospinal fluid circulation causing intracranial hypertension without ventriculomegaly. Arch Neurol 1991; 48: 740- 7. 2. Green JP, Newman NJ, Stowe ZN, Nemeroff CB. " Normal pressure" pseudotumor cerebri. J Neuroophthalmol 1996; 16: 196- 8. J Neuro- Ophthalmol, Vol. 17, No. 4, 1997 LETTERS TO THE EDITOR 281 A Letter from the Editor A member of our Board appropriately and succinctly wrote the following side- bar to a review of a submitted manuscript. I believe it should stand us all well if we take the advice to heart: " The case reports and discussion are replete with ophthalmic abbreviations. Personally, I think this practice should stop in our Journal. We intend that articles published in the Journal should stand on their own as legitimate neurologic publications fit for publication in mainline neurologic journals. If we allow ophthalmologic abbreviations in the text of our publications, we limit our readership." The editorial board and I would advise our authors to rewrite their manuscript in plain English that will be understandable to nonophthalmologic physicians. Ronald M. Burde, M. D. Editor- in- chief J Neuro- Ophthalmol, Vol. 17, No. 4, 1997 |