Cell culture isolation can miss the laboratory diagnosis of HSV ocular infection.

AIM: We compared polymerase chain reaction (PCR) to cell culture isolation for the laboratory diagnosis of ocular herpes simplex virus (HSV) disease. METHODS: Laboratory and medical records of consecutive patients were reviewed for results of 1) HSV PCR testing, 2) HSV cell culture isolation, and 3) clinical diagnosis. PCR results were statistically compared to cell culture isolation and patients initially diagnosed for ocular HSV infection. RESULTS: Of 581 cases submitted for laboratory testing, 520 were PCR negative, cell culture negative (89.6%); 0 were PCR negative, cell culture positive (0%); 27 were PCR positive, cell culture negative (4.6%); and 34 were PCR positive, cell culture positive (5.8%). PCR tested more positive than cell culture isolation (McNemar's, P=0.0001). Of 47 HSV PCR positive cases with complete medical records, 19 were cell culture negative for HSV and 28 were cell culture positive for HSV. Fourteen of 19 cell culture negative cases (74%) (Without PCR, 5 cases of HSV would be missed) and 25 of the 28 cell culture positive cases (89%) (Laboratory testing was necessary for diagnosing 3 cases) were clinically diagnosed with HSV at the initial examination. CONCLUSION: PCR was a more definitive test for diagnosing HSV ocular infection than cell culture isolation. Cell culture isolation alone can miss an atypical presentation of HSV ocular infection.

Spectral domain optical coherence tomography for detection of foveal morphology in patients with nystagmus.

PURPOSE: To evaluate the feasibility of spectral domain optical coherence tomography (SD-OCT) macular scanning as a means of studying the afferent visual system in nystagmus patients. METHODS: Nystagmus patients who underwent SD-OCT, clinical evaluation, and eye movement recordings were recruited for this prospective, single-center, noncomparative study. Three SD-OCT macular three-dimensional cube scans per eye (200 x 200 x 1024 samplings in a 6 x 6 mm region) were obtained for qualitative retinal morphology analysis. RESULTS: Nineteen patients (6-68 years; average, 19 years) were analyzed. Of these, 17 patients had infantile nystagmus syndrome, and 2 had fusion maldevelopment nystagmus; 17 patients (89%) had associated sensory system abnormalities, including 9 (47%) with albinism. Macular images were successfully obtained in all but 1 patient (95%). Of the 8 successfully imaged oculocutaneous patients, 7 patients demonstrated "fovea plana," and all demonstrated abnormal morphology. CONCLUSION: SD-OCT reliably provides detailed structural imaging of the fovea in nystagmus patients.

Accuracy and performance of a commercially available Dosing Aid.

AIM: To evaluate the recently introduced Travatan Dosing Aid (TDA) for its accuracy in recording and dispensing eyedrops. METHODS: The number of eyedrops dispensed with each lever depression and agreement of total number of drops dispensed with that recorded by the device was evaluated in a controlled setting. RESULTS: The TDA correctly recorded a drop being dispensed 100% of the time with full TDA lever depression for <3 s. Under these conditions, agreement between numbers of drops dispensed and recorded was 99%. However, failure to fully depress the lever or prolonged lever depression for >4 s resulted in unreliable TDA recording. CONCLUSION: Eyedrops were reliably recorded by the TDA after each full lever depression. However, patients need to be instructed about optimal technique so that evaluation of compliance is not confounded by mechanical factors.

Graded partial tenotomy of vertical rectus muscles for treatment of hypertropia.

PURPOSE: To evaluate the effectiveness of graded (adjustable intraoperatively) partial vertical rectus muscle tenotomy at the insertion in correcting small degrees of hypertropia. METHODS: All patients with best-corrected visual acuity of better than 6/30 in both eyes who over a 30-month period underwent partial tenotomy of vertical rectus muscle(s) only (no concurrent oblique muscles) were included. Improvement was evaluated 6 weeks postoperatively as change in alignment in prism diopters (PD) in primary gaze and in the field of action of the affected rectus muscle(s). Binocular function was evaluated by Titmus stereoacuity and the Worth 4-light tests. RESULTS: All 24 patients who met criteria for inclusion had diplopia preoperatively versus seven patients (29%) postoperatively (P < .005, Student's paired t test). Prisms were used by six preoperatively versus two postoperatively (P < .05, Student's paired t test). The average vertical deviation in primary gaze decreased from 8 PD to 2 PD (P < .005, Student's paired t test). In the field of action of the treated rectus muscle, hypertropia decreased from an average of 8 PD to 3 PD (P < .005, Student's paired t test). For the preoperative and the postoperative assessments available, stereoacuity improved after 10 (56%) of the 18 procedures and Worth 4-light testing showed improvement or maintenance of fusion after 15 (79%) of 19 procedures. CONCLUSIONS: Graded vertical rectus partial tenotomy can effectively reduce small degrees of hypertropia and associated diplopia, improve binocular function, and reduce or eliminate the need for prism correction.