Inadvertent Blebs Research Articles

Complications of inadvertent filtering blebs after cataract extraction

We report 2 cases of inadvertent filtering blebs that developed vision-threatening complications many years after uneventful cataract extraction with scleral incisions. These inadvertent blebs can create complications similar to the intentionally produced blebs from trabeculectomy surgery; thus, follow-up and management should be handled in a similar manner. No author has a financial or proprietary interest in any material or method mentioned.

Histopathologic Features of Conjunctival Filtering Blebs

To characterize and compare the histological features of conjunctiva obtained during the repair of trabeculectomy and inadvertent blebs and to assess the effects of antifibrotic agents. We used routine paraffin processing and light microscopy to examine conjunctival specimens from 28 eyes undergoing late bleb revision: 19 leaking trabeculectomy blebs, 5 nonleaking trabeculectomy blebs, and 4 inadvertent blebs. Quantitative analysis of histological characteristics included conjunctival epithelial thickness, stromal vascularity, squamous metaplasia, stromal inflammatory cell infiltrate, and goblet cell density. The type of surgery, presence of leaks, prior topical medication, and antifibrotic use were correlated with histological findings. Trabeculectomy blebs (leaking and nonleaking) showed decreases in overall epithelial thickness (P<.02), goblet cell density (P<.001), and vascularity (P<.001) compared with inadvertent bleb controls. Conjunctiva exposed to antifibrotics had fewer layers of epithelial cells than those with no prior exposure (P<.05). Histological analysis of thin blebs excised following trabeculectomy demonstrated decreases in epithelial thickness and goblet cell density compared with inadvertent blebs. Both leaking and nonleaking trabeculectomy blebs exhibited decreases in localized stromal vascularity and increases in surrounding stromal vascularity compared with normal conjunctiva.

New patterns of infecting organisms in late bleb-related endophthalmitis: a ten year review.

To report the risk factors, causative organisms and visual outcomes in patients with late-onset bleb-related endophthalmitis. Medical records of all patients with the clinical diagnosis of late-onset bleb-related endophthalmitis undergoing vitreous aspirates for culture at our institution from January 1987 to July 1996 were reviewed. Late-onset bleb-related endophthalmitis was defined as conjunctival injection, bleb purulence and intraocular inflammation developing at least 1 month following filtering surgery. Forty-nine cases of bleb-related endophthalmitis developed in 42 patients (23 men, 19 women). Mean patient age was 62.1 +/- 19.3 years (range 5-94 years). Thirty-nine patients underwent prior filtering surgery (superior trabeculectomy, 24 eyes; inferior trabeculectomy, 10 eyes; combined superior trabeculectomy/cataract extraction, 4 eyes; posterior lip sclerectomy, 1 eye) and 3 had inadvertent blebs following cataract extraction. Endophthalmitis developed an average of 25.4 +/- 23.5 months (range 1-96 months) post-operatively. Antifibrosis agents were used in 25 of 39 eyes undergoing filtering surgery (mitomycin C, 13 eyes; 5-fluorouracil, 12 eyes). Bleb leaks were documented in a total of 32 of 49 (65%) cases either before or at the time of endophthalmitis diagnosis. Vitreous cultures were positive in 42 of 49 (86%) cases. The most frequently cultured organisms were Staphylococcus aureus (13), Staphylococcus epidermidis (12), Streptococcus species (8) and Haemophilus influenzae (2). A final visual acuity of 20/400 or better was achieved in 32 of 49 (65%) cases. Staphylococcal species were the most frequently cultured organisms in this series and may be associated with better visual outcomes. Although a causal relationship cannot be established, these results suggest a strong association between bleb leaks and endophthalmitis.

An Unusual Complication of a Postcataract Filtering Bleb

Inadvertent blebs are sometimes encountered after cataract surgery using sutured limbal incisions. A number of surgical techniques have been described in the planned management of such blebs. Occasionally, an intraoperative bleb rupture may occur. The authors describe a rotational scleral autograft technique that can help in the management of this complication.

Late Onset Endophthalmitis Associated With Filtering Blebs

A consecutive series of 71 cases of late onset endophthalmitis (defined as onset of symptoms at least 2 weeks after surgery) were reviewed to determine the association of this entity with glaucoma surgery filtering blebs and to identify any predisposing factors. Sixteen cases were associated with filtering blebs and two with inadvertent blebs following cataract surgery. Onset of endophthalmitis ranged from 24 days to 20 years after surgery (mean, 6.9 years). Possible contributing factors included trauma, vitreous wicks, and bleb leak. Twelve cases were culture-positive, with 5 cases of Staphylococcus epidermidis; 2, Staphylococcus aureus; 4, Streptococcus; and 1, Pseudomonas. There were no cases of Hemophilus. The more virulent organisms were generally associated with a poor visual outcome. The organisms recovered in this series were similar to those found in postoperative endophthalmitis not associated with filtering blebs.