OCR Text |
Show Ll'lll'rs to tht' Editor Reply to Fourth Nerve Palsy Opposite a Black Eye To the Editor: I ,lpprt'ci,lte tlwse comments on the often diffinlft eMly di,l~n()sis llf postlr,lUm,ltic verticdl dip/api, l. r,lthoillgic,ll verific,ltion of trochleM nerve d,lm,lge is virtu,llly never obtdined, dnd the didgnosis of ,1 fourth nerve pJlsy necessdrily is bdsed upon the best dinic.ll fit. The bl,lrk eye is the mJjor distr.lction in these C,lses. Once dttention is directed to the other eye, ch,Hdcterization is reldtively str.lightforwdrd: posttrJumdtic incomitdnt hypertropid, with principdl limitJtion in the field of action of the superior oblique muscle, worsening with ipsilaterdl head tilt. Whether one argues from pdrsimony, primdry muscle limitation, d two- or three-step hedd-tilt procedure, or the rule of Aunt Minnie,' the didgnosis is thdt of a left trochlear nerve palsy in each case. • Anr;ent prinriple of CE'stJlt diJgn(lsis in which it is JrguE'd th,'t Sl)J1WOnE' With In JppE'JrJncE' identlrJI to Aunt Minnie. pwbJbly IS Aunt MinniE'. A minor spread of concomitance along either or both drms of the "L" is not an impediment to the didgnosis. Spread of concomitance undoubtedly begins upon onset of ocular m::>tor dysfunction and proceeds at highly varying rates. Major concomitdnt spread has been observed within 3 weeks of trochlear nerve injUry, I. ~ and concomitance may be present dt the onset of diplopia from dbducens pdlsies." The dlterndtive suggestions are interesting and provocative but not very likely. These patients are dedd ringers for my Aunt Minnie. James R. Keane, MD. Los Angeles, California References I. Knapp, P.: Diagnosis and surgical treatment of hypertropia. Am. Orthop. I 21: 29-37, 1971. 2. Moore,S., and Stockbridge, L.: Diagnostic observation on acquired unilateral and bilateral superior oblique palsies. Proc. Second Int. Orthop. Congo Excerpta. 266-269, 1972. 3. Kirkham, T.H., Bird, A. c., and Sanders, M.D.: Divergence paralysis with raised intracranial pressure: An electrooculographic study. Br. I OphthaImol. 50: 77b- 782, 1972. Journal of Clinical Neuro-ophthalmo)ogy |