Anterior chemodenervation of levator palpebrae superioris with botulinum toxin type-A (Botox®) to induce temporary ptosis for corneal protection

AIM

To evaluate the effectiveness of anterior chemodenervation of levator palpebrae superioris with Botulinum toxin type A (Botox) to induce temporary ptosis for corneal protection, and assess the incidence of superior rectus underaction.

METHODS

Prospective interventional case series. Patients with ocular surface pathology requiring temporary tarsorrhaphy underwent transcutaneous anterior chemodenervation of levator palpebrae superioris with Botox. The onset and duration of ptosis, corneal healing, and superior rectus underaction was evaluated.

RESULTS

Ten eyes of 10 patients underwent transcutaneous anterior chemodenervation of levator muscle. Five patients had Bells palsy with exposure keratopathy, four patients had persistent epithelial defect, and one had neurotrophic ulcer. The median age at presentation was 30 years. Median dose of Botulinum toxin injection was 12.5 U (range 10-15 U). The mean palpebral fissure height of 9 mm (SD+/-2.1 mm) before injection, reduced to 2.8 mm (SD+/-1.9 mm) at 1-week post-injection. More than 50% reduction in palpebral fissure height was seen in nine out of 10 eyes (90%, 95% CI 71.4-100%) at 1 week, seven of nine eyes (77.8%, 95% CI 50.6-100%) at 2 weeks, and two of nine eyes (22.2%, 95% CI 0-49.4%) at 4 weeks, and returned to pretreatment level after mean duration of 9.2 weeks (range 5-16 weeks). Superior rectus underaction was not noted in any of the patient (95% CI 0-30%). Corneal pathology improved in all cases.

CONCLUSION

Anterior chemodenervation of levator palpebrae superioris with Botulinum toxin type A (Botox) induces significant temporary ptosis and aids in corneal healing. Anterior placement of the toxin injection may avoid superior rectus underaction.

Outcome of pterygium surgery: analysis over 14 years

AIM

To report the outcome of pterygium surgery performed at a tertiary eye care centre in South India.

METHODS

Retrospective analysis of medical records of 920 patients (989 eyes) with primary and recurrent pterygia operated between January 1988 and December 2001. The demographic variables, surgical technique (bare sclera, primary closure, amniotic membrane transplantation (AMT), conjunctival autograft (CAG), conjunctival-limbal autograft (CLAG), or surgical adjuvants), recurrences and postoperative complications were analysed.

RESULTS

A total of 496 (53.9%) were male and 69 (7.5%) had bilateral pterygia. Bare sclera technique was performed in 267 (27.0%) eyes, primary conjunctival closure in 32 (3.2%), AMG in 123 (12.4%), CAG in 429 (43.4%), and CLAG in 70 (7.1%). Adjuvant mitomycin C was used in 44 (4.4%) cases. The mean duration of follow-up was 8.9+/-17.0 and 5.9+/-8.8 months for unilateral primary and recurrent pterygia, respectively. The overall recurrence rate was 178 (18.0%). Following primary and recurrent unilateral pterygium excision respectively, recurrences were noted in 46 (19.4%) and 1 (33.3%) eyes after bare sclera technique, five (16.7%) and 0 after primary closure, 28 (26.7%) and 0 with AMG, 42 (12.2%) and five (31.3%) with CAG, and nine (17.3%) and two (40%) with CLAG. Recurrences were significantly more in males with primary (23.3 vs 10.7%, P<0.0001) and recurrent (26.7 vs 0%, P=0.034) pterygia, and in those below 40 years (25.2 vs 14.8%, P=0.003).

CONCLUSION

CAG appears to be an effective modality for primary and recurrent pterygia. Males and patients below 40 years face greater risk of recurrence. Bare sclera technique has an unacceptably high recurrence. Prospective studies comparing CAG, CLAG, and AMG for primary and recurrent pterygia are needed.

Regulation of apoptosis by vasoactive peptides

Although originally discovered because of their ability to affect hemodynamics, vasoactive peptides have been found to function in a variety of capacities including neurotransmission, endocrine functions, and the regulation of cell proliferation. A growing body of evidence describes the ability of vasoactive peptides to regulate cell death by apoptosis in either a positive or negative fashion depending on the peptide and the type of target cell. The available evidence to date is strongest for the peptides endothelin, angiotensin II, vasoactive intestinal peptide, atrial natriuretic peptide, and adrenomedullin. Each of these peptides is discussed, with specific regard to apoptosis, in terms of regulatory activity, target cell specificity, and potential role in pulmonary physiology.

Norepinephrine induces alveolar epithelial apoptosis mediated by alpha-, beta-, and angiotensin receptor activation

Norepinephrine (NE) induces apoptosis in cardiac myocytes, and autocrine production of angiotensin (ANG) II is required for apoptosis of alveolar epithelial cells (AECs) (Wang R, Zagariya A, Ang E, Ibarra-Sunga O, and Uhal BD. Am J Physiol Lung Cell Mol Physiol 277: L1245--L1250, 1999; Wang R, Alam G, Zagariya A, Gidea C, Pinillos H, Lalude O, Choudhary G, and Uhal BD. J Cell Physiol 185: 253--259, 2000). On this basis, we hypothesized that NE might induce apoptosis of AECs in a manner inhibitable by ANG system antagonists. Purified NE induced apoptosis in the human A549 AEC-derived cell line or in primary cultures of rat AECs, with EC(50) values of 200 and 20 nM, respectively. Neither the alpha-agonist phenylephrine nor the beta-agonist isoproterenol could mimic NE when tested alone but when applied together could induce apoptosis with potency equal to NE. Apoptosis and net cell loss (47--59% in 40 h) in response to NE was completely abrogated by the ANG-converting enzyme inhibitor lisinopril or the ANG II receptor antagonist saralasin, each at concentrations capable of blocking Fas- or tumor necrosis factor-alpha-induced apoptosis. These data suggest that NE induces apoptosis of human and rat AECs through a mechanism involving the combination of alpha- and beta-adrenoceptor activation followed by autocrine generation of ANG II.

Fluoroquinolone and fortified antibiotics for treating bacterial corneal ulcers

AIM

To compare the clinical efficacy of commercially available fluoroquinolone drops with the use of combined fortified antibiotics (tobramycin 1.3%-cefazolin 5%) in treatment of bacterial corneal ulcer.

METHODS

The medical records of 140 patients with a diagnosis of bacterial corneal ulcer who were admitted to the Royal Victorian Eye and Ear Hospital, Melbourne, Australia between January 1993 and December 1997 were reviewed retrospectively. Final outcome and results of 138 ulcer episodes were compared between those treated initially with fluoroquinolone and those who received fortified antibiotics. Two patients had been treated with chloramphenicol.

RESULTS

No significant treatment difference was found between fluoroquinolone and fortified therapy in terms of final visual outcome. However, serious complications such as corneal perforation, evisceration, or enucleation of the affected eye were more common with fluoroquinolone therapy (16.7%) compared with the fortified therapy (2.4%, p= 0.02). The duration of intensive therapy was less with fluoroquinolone especially in those over 60 years of age (4 days v 6 days, p=0.01). Hospital stay was also less in the fluoroquinolone group compared with the fortified group for all patients and was significantly less with fluoroquinolone treatment (7 days v 10 days, p=0.02) in patients in the age group over 60 years old.

CONCLUSIONS

Monotherapy with fluoroquinolone eye drops for the treatment of bacterial corneal ulcers led to shorter duration of intensive therapy and shorter hospital stay compared with combined fortified therapy (tobramycin-cefazolin). This finding may have resulted from quicker clinical response of healing as a result of less toxicity found in the patients treated with fluoroquinolone. However, as some serious complications were encountered more commonly in the fluoroquinolone group, caution should be exercised in using fluoroquinolones in large, deep ulcers in the elderly.