Axial length in keratoconus.

Axial length is a major determinant of ocular refractive power that has not been well established for keratoconus eyes. The purpose of this study was to establish the mean and range of axial length among both keratoconus eyes with no previous surgery and postkeratoplasty keratoconus eyes, and to determine if there is a significant reduction of axial length following variations in surgical techniques in penetrating keratoplasty. The axial length of 157 keratoconus eyes with no previous surgery was measured using applanation ultrasonography. The mean axial length measurement was 24.39 (+/- 1.13 mm), with a range of 21.82-28.69 mm. The axial length of 66 postkeratoplasty keratoconus eyes was similarly measured. The mean axial length measurement was 24.10 (+/- 1.22 mm), with a range of 21.83-26.87 mm. These values are not significantly different from the axial length mean and range found among emmetropic eyes. A significant shortening of the axial length (F = 5.2, p = 0.04) was obtained in the postoperative penetrating keratoplasty eye if the donor trephine was 0.3 mm smaller in diameter than the recipient trephine. The axial length of individual keratoconus eyes is a major factor in determining postoperative refractive error. It therefore becomes important when considering variations in surgical procedures to reduce postoperative myopia.

Nontuberculous mycobacterial keratitis. Report of two cases and review of the literature.

We report two cases of nontuberculous mycobacterial keratitis. To our knowledge, case 1 is the first documented case of Mycobacterium chelonei sclerokeratitis and case 2 is the first report of Mycobacterium flavescens keratitis. A total of 40 cases of nontuberculous mycobacterial keratitis involving at least five different species have been reported previously in the literature. Almost all of these opportunistic infections have occurred following either accidental or surgical ocular trauma, usually associated with the use of local corticosteroids. Encountered infrequently, these organisms can be incorrectly identified as other bacteria, including diphtheroids and Nocardia species. Histopathologic examination and special stains of infected tissues may be helpful in establishing the correct diagnosis. Cultures and sensitivity testing are mandatory in determining appropriate treatment.

Limb leads of the electrocardiogram: sequencing revisited.

The six limb leads are normally presented in a format the logic of which is traditional rather than anatomical and does not allow visual interpolation such as is customary with the six chest leads. The sequence: a VL, I, -aVR, II, aVF, III was suggested years ago, and is used in some European countries, particularly Sweden. It provides a better impression of the extent of the changes of inferior infarction and makes the rather neglected lead aVR much more useful, though reversed in polarity. It also provides a more direct indication of the electrical axis, and simplifies comparisons with the frontal plane vectorcardiogram. Because modern digital electrocardiographs can provide the sequenced format, this seems a good time to review the advantages of adopting it.

Coxsackie B5 heart disease. Demonstration of inferolateral wall myocardial necrosis.

A case of Coxsackie B5 viral myopericarditis is presented in which the diagnosis of inferolateral wall myocardial necrosis was made on the basis of specific cardiac enzyme changes and radionuclide myocardial imaging. This localized damage may have resulted from coronary arteritis with resulting infarction or necrosis secondary to preferential viral involvement of the inferolateral wall of the myocardium. Hepatitis and cerebral embolism complicated the case, with the latter suggesting endocardial disease.