Filtering bleb functionality: a clinical, anterior segment optical coherence tomography and in vivo confocal microscopy study.
OBJECTIVE
To provide a microscopic and macroscopic analysis by a clinical, in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) assessment of filtering blebs after glaucoma surgery.


METHODS
We retrospectively analyzed 60 eyes of 48 glaucomatous patients by slit-lamp, IVCM, and AS-OCT examinations. Patients were divided into 2 groups: successful blebs (group 1, 16 patients, 27 eyes) were defined as a one-third reduction in preoperative intraocular pressure without antiglaucoma medications and failed blebs (group 2, 32 patients, 33 eyes) as a less than one-third reduction in preoperative intraocular pressure without therapy. The examinations were performed from 1 to 96 months postoperatively.


RESULTS
Diffuse or cystic clinical patterns were indicative for good functionality whereas flat or encapsulation was indicative for poor functionality. When comparing successful with failed blebs, the IVCM analysis showed a greater number (P=0.014), density (P=0.009), and total area of epithelial microcysts (P=0.017) and a lower density of connective tissue (P=0.006). The AS-OCT analysis showed a lower degree of bleb wall reflectivity (P<0.001). A significant correlation was found between the clinical and AS-OCT parameters, particularly for the cystic (100%) and diffuse (74%) patterns.


CONCLUSIONS
All IVCM parameters did correlate well with the bleb functionality whereas, among the AS-OCT parameters, only the bleb wall reflectivity was significantly related to the filtering capability. Clinical and AS-OCT bleb classification showed a significant degree of concordance. As a consequence, simultaneous approach by clinical, microscopic, and tomographic assessment improves the clinician's ability in the postsurgery understanding and management of blebs.
Department of Medicine and Aging Science, Ophthalmic Clinic, University of Chieti-Pescara, Italy. m.ciancaglini@unich.it
Marco
M
Ciancaglini
Paolo
P
Carpineto
Luca
L
Agnifili
Mario
M
Nubile
Manuela
M
Lanzini
Vincenzo
V
Fasanella
Leonardo
L
Mastropasqua
D000368:Aged; D000869:Anterior Eye Segment / Q000473:pathology*; D001082:Aqueous Humor / Q000378:metabolism; D001768:Blister / Q000175:diagnosis*; D003228:Conjunctiva / Q000502:physiology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000601:surgery; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D012189:Retrospective Studies; D013524:Surgical Flaps / Q000502:physiology*; D041623:Tomography, Optical Coherence; D014065:Tonometry, Ocular; D014130:Trabeculectomy