Humphrey Matrix perimetry in optic nerve and chiasmal disorders: comparison with Humphrey SITA standard 24-2.

PURPOSE: To compare the Humphrey Matrix 24-2 perimetry (Matrix; Carl Zeiss Meditec, Inc., Dublin, CA) with the standard automated perimetry Humphrey Visual Field Analyzer using SITA (Swedish Interactive Threshold Algorithm) program 24-2 (SAP; Carl Zeiss Meditec, Inc.) in neuro-ophthalmic disorders affecting the optic nerve and chiasm. METHODS: Matrix and SAP were performed on 93 patients with neuro-ophthalmic disorders affecting the optic nerve and optic chiasm. Three readers compared the total and pattern deviation probability plots and judged the similarity and the extent of the visual field defects. The sensitivity and specificity of both perimeters were calculated. RESULTS: Concordance was good in 61%, fair in 30%, and poor in 9% of the total deviation plots. For the pattern deviation, concordance was good in 52%, fair in 34%, and poor in 14%. The extent of field loss was equal in 50%, 23% more extensive with Matrix, and 27% more extensive with SAP for total deviation plots. For the pattern deviation, the extent was equal in 47%, 20% more extensive with Matrix and 33% more extensive with SAP. The sensitivity for detecting defects was 84% (SAP) and 77% (Matrix) for total deviation and 80% (SAP) and 79% (Matrix) for pattern deviation (no significant difference, P > 0.05). The specificity was 84% (SAP) and 86% (Matrix) for total deviation and 68% (SAP) and 74% (Matrix) for pattern deviation (no significant difference, P > 0.05). CONCLUSIONS: The new Humphrey Matrix 24-2 testing strategy provides a visual field testing method for optic nerve and chiasmal disorders that has fair to good concordance with the Humphrey SITA Standard 24-2 program. Both tests have similar sensitivity and specificity.

Sensitivity and specificity of the Humphrey Matrix to detect homonymous hemianopias.

PURPOSE: To compare the sensitivity and specificity of the Humphrey Matrix frequency-doubling perimeter (Carl Zeiss Meditec, Inc., Dublin, CA) to that of standard automated perimetry (SAP) in detecting homonymous hemianopic visual field defects. METHODS: Thirty-three patients with homonymous hemianopias and 50 normal subjects were tested with SAP with the Humphrey Visual Field Analyzer (SITA standard program 24-2) and Humphrey Matrix frequency-doubling perimetry, program 24-2 (Matrix) on the same day. Patients with hemianopias had lesions of the retrochiasmal visual system that were documented by magnetic resonance imaging or by computed tomography. To be classified as a hemianopic visual field defect, the abnormal test location had to be homonymous, respect the vertical meridian, and have no additional scattered abnormal points that obscured the hemianopic pattern. The sensitivity and specificity of SAP and Matrix in detecting hemianopic defects were calculated. The chi(2) test was used to test for differences between groups. RESULTS: The sensitivity for hemianopic defects by total deviation probability plots was 75% for SAP and 59% for Matrix (not statistically significant, P = 0.29). The sensitivity of hemianopic defects by pattern deviation probability plots was 88% for SAP and 69% for Matrix (not statistically significant, P = 0.13). The specificity of total deviation probability plots was 84% for SAP and 86% for Matrix. The specificity of the pattern deviation probability plots was 68% for SAP and 74% for Matrix. CONCLUSIONS: Although there was no statistically significant difference between the Matrix and SAP in the detection of hemianopias, the sensitivity of SAP was higher, probably because of the obscuration of defects by scattered abnormal test locations with the Matrix.

Infectious scleritis after pars plana vitrectomy because of methicillin-resistant Staphylococcus aureus resistant to fourth-generation fluoroquinolones.

PURPOSE: To describe a case of infectious scleritis caused by methicillin-resistant Staphylococcus aureus (MRSA) after pars plana vitrectomy despite treatment with topical fourth-generation fluoroquinolones. METHODS: Single interventional case report. RESULTS: A 72-year-old man presented with scleral thinning and subconjunctival abscess 1 month after pars plana vitrectomy. Microbiological studies including cultures and antibiotic sensitivity were performed. Culture of the scleral abscess showed growth of MRSA resistant to fourth-generation fluoroquinolones and sensitive to vancomycin and erythromycin. Treatment with a combination of topical vancomycin and systemic erythromycin for 6 weeks resolved the infectious scleritis. CONCLUSIONS: MRSA can be a cause of infectious scleritis after ocular surgery without a clear source despite surgical prophylaxis with topical fourth-generation fluoroquinolones.