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the slit lamp, with the chin on the chin rest and forehead at or at least close to the crossbar, there may be a great deal of moving, struggling, squirming, and breathholding. Because of the resultant Valsalva effect, the ocular pressure read ing may be artificially high when indeed the patient's true ocular pressure is well within the normal range. CASE REPORT A 68-year-old obese woman was seen for ophthmologic examination and ocular pressure was found by Goldmann applanation tonometer to be 27 mm Hg in both eyes. Disks were physiologic with Grade 1 cupping. Forty minutes after instillation of timolol 0.25% the pressure read 22 mm Hg in both eyes and medication was started. One month later the pressure measured 25 mm Hg in both eyes by applanation and the dosage was increased to 0.50% every 12 hours. Central fields were full with normal blind spots. Three months later the pressure was again 25 mm Hg in both eyes. On a hunch, after noticing the patient's tre mendous struggle to get close to and stay at the slit lamp, including holding and pulling on the platform of the stand, I borrowed a Schi^tz tonometer from a colleague. The patient's pressure measured 18.9 mm Hg in both eyes with a 5.5-g weight and 18.5 mm Hg in both eyes with a 7.5-g weight. Pilocarpine was instilled and one hour later the pressure measured 17.3 and 17 mm Hg, respectively, with the Schi0tz tonometer.
I suggest that tonometry other that slitlamp tonometry be tried on these rotund obese patients if there is a question of increased ocular pressure. NAPHTALI GUTSTEIN,
Alternative Tarsorraphy in Peripheral Facial Nerve Paralysis Editor: Lagophthalmos secondary to facial nerve paralysis may be associated with keratitis, conjunctivitis, or both. A partial tarsorraphy is sometimes required to re duce the width of the palpebral fissure. In three patients with peripheral facial nerve paralysis I avoided tarsorraphy by gently pinching a thin fold of the skin
p£2 ;~3ir Figure (Scoppetta). A patient with bilateral facial paralysis caused by acute postinfective polyneuritis (A) and Bell's phenomenon (B) applies two clamps (C) and is able to close his eyes (D).
close to the external palpebral commis sure by using a small clamp. The results seemed to be satisfactory. The patient uses the clamp at intervals as the paralysis improves until the device is no longer required. The procedure is particularly useful in patients who are acutely ill. CIRIACO SCOPPETTA,
Vitrectomy for Diabetic Traction Retinal Detachment Editor: I don't know whether to be dismayed or tremendously impressed by the absence of corneal complications reported in the article, "Vitrectomy for diabetic traction retinal detachment" (Am. J. Ophthalmol. 88:246, 1979), by T. A. Aaberg. The inci dence of corneal complications in diabet-
AMERICAN JOURNAL OF OPHTHALMOLOGY
ics undergoing vitrectomy was first dis cussed in detail by Brightbill, Myers, and Bresnick in 1978. 1 They noted that "corneal complications after . . . vitrectomy are virtually confined to diabetic cases." This observation was later confirmed by Perry and associates, 2 who showed that of those diabetics undergoing vitrectomy, 54% were destined to show corneal com plications. It is certainly understandable that for a retinal surgeon, the cornea is frequently a mere nuisance. Nevertheless, it would be most interesting to know if corneal prob lems did develop in this series of 75 cases, and were omitted from this discussion, or if Dr. Aaberg is doing something that the rest of us should know about. D A V I D W. L A M B E R T S ,
REFERENCES 1. Brightbill, F. S., Myers, F. L., and Bresnick, G. H.: Postvitrectomy keratopathy. Am. J. Ophthalmol. 85:651, 1978. 2. Perry, H. D., Foulks, G. N., Tlioft, R. A., and Tolentino, F. I.: Corneal complications after closed vitrectomy through the pars plana. Arch. Ophthalmol. 96:1401, 1978.
Reply Editor: The problem of corneal abnormalities after vitrectomy surgery has been a major problem in the past. The concern for the corneal consequences of vitrectomy sur gery has been evaluated by me and by scientists at the Medical College of Wis consin, in several previous publications. Therefore, none of us have considered the cornea to be merely "a nuisance," and we have not treated it in a cavalier fashion. The patients comprising the series men tioned in my article were examined metic ulously concerning the corneal status preand postoperatively. During the first half
of the study, all patients had preoperative pachometry and postoperative pachometry. The results of this study have been reported. 1 The results of that evaluation, as well as the results of evaluation in the continuing series, indicate that advances in vitrec tomy, irrigating solutions, and knowledge of the toxicity of topical medications have greatly reduced the corneal problems. No patients in the present series had longterm corneal problems. The improved ir rigating solutions, as developed at the Medical College of Wisconsin by Edelhauser and co-workers, 2 3 have reduced the necessity for scraping corneal epithe lium and thus reduced the incidence of postoperative epithelial sloughing. Main taining phakic eyes has also reduced the incidence of corneal abnormalities. Addi tionally, the ocular problems have been reduced by not using more than a 5% solution of topical phenylephrine, thus reducing the toxicity to both epithelium and endothelium, as demonstrated by Edelhauser and associates. 4 Thus, I do not have any secrets for reducing corneal problems inasmuch as all of the data have been previously pub lished. The combination of these advanc es plus reduced intraocular irrigation, re sulting from improvements in surgical technique and decreased instrument size, have fortunately made the previous reports of severe corneal problems out dated. T H O M A S M. A A B E R G ,
REFERENCES 1. Aaberg, T. M., Edelhauser, H., Hogue, D., and Riddle, P.: Vitrectomy solutions. Their effect on corneal thickness. Presented at the Association for Research in Vision and Ophthalmology Annual Meeting, April 29, 1976. 2. Edelhauser, H. F., Van Horn, D. L., and Hyndiuk, R. A.: Intraocular irrigating solutions. Their effect on corneal endothelium. Arch. Ophthalmol. 93:648, 1975.