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The purpose of this communication is to report a short study of the prevalence of muscle imbalance in cases of myopia and its influence as a causative factor in the onset and progressiveness of this condition. In an article published in 1895, I1laid stress on the fact that among the 245 cases of myopia there recorded not one could be described as simple myopia. At least one of three presumably congenital conditions—astigmatism, anisometropia and muscle imbalance—was demonstrable in each. In many cases all three were present. Experience since then has failed to demonstrate any case of myopia in which all these conditions could be positively excluded, and doubt therefore arose as to whether there is such a thing as simple myopia. If there is, it must be exceedingly rare. This refers, of course, only to axial myopia. In cases of myopia there are, therefore, two groups

Two of the most eminent authorities on muscle imbalance of the last half-century, Alexander Duane and Ernest E. Maddox, have enunciated the essential conditions of a satisfactory test for the muscle balance. Duane was the most strenuous advocate of the objective cover test with its subjective complement, the parallax test. Maddox, in referring to this cover test in an introductory address on heterophoria before the Ophthalmological Society of the United Kingdom, 1929, said that the most important thing was to keep the eye "covered long enough for the deviation to develop. " The prolonged occlusion test is a combination of these two conditions. It puts into practice the principles which these two authorities have preached. It seems doubtful, however, whether either of them put the combined principles into practice and carried out an actual prolonged test. Indeed, it is doubtful whether Maddox realized the full significance of his

No comprehensive and single hypothesis has been put forward to account for the phenomena grouped under the term heterophoria. Certain conditions underlying it have been mentioned, such as overdevelopment, faulty insertion or length of the muscle. The so-called declinations described by Stevens have also been considered responsible for some of these phenomena. Aniseikonia, too, has been mentioned as a possible cause, as has paresis or partial paralysis. The chief character of these anomalies is their variability. These conditions may be said to be underlying anatomic states rather than causes. It is necessary to take a step farther back and ask what is the cause of these underlying states. It seems lacking in reason to attribute a variety of possibly causative conditions to phenomena which are fairly uniform in their manifestation, if one excludes the cases in which the etiologic factor is definitely paralysis or trauma. When the subject

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Meningococcemia, unaccompanied by meningitis, or with meningitis occurring as a late complication, continues to be reported with great rarity in the United States. In 1924 Dock1 was able to find reports of nine cases in the American literature, and since that time only four more have been published. In contrast, the foreign literature contains reports of approximately 110 cases. Dock believed that this discrepancy was due not so much to the greater frequency of the condition abroad as to the lack of knowledge of the disease in this country. There is no way of settling this question, but it is certain that those cases which have been reported here do not exemplify the typical picture as it is known in Europe. In many instances the signs and symptoms are sufficiently characteristic to warrant a presumptive diagnosis before bacteriologic confirmation. The present case was so diagnosed by a visiting physician.

To the Editor.—In Pascal's clinical note on myopia and exophoria in the October issue of theArchives(p. 624) stress was laid chiefly on the occurrence of exophoria, and no reference was made to the presence of other forms of muscle imbalance. My recent paper (Muscle Imbalance in Myopia,Arch. Ophth. 13: 584 [April] 1935), to which Pascal made kindly reference, shows, however, that other forms of imbalance besides exophoria are apt to be present, notably, hyperphoria. In the cases on which this paper was based hyperphoria was present in the same number of instances as exophoria. As a matter of fact, pure exophoria was present in only 12 per cent of the cases in which the occlusion test was performed. The commonest form of muscle imbalance found was a combination of vertical and lateral deviation (usually exophoria), this occurring in forty of fifty cases, or in 80 per cent.