Fig. 12. UBM features in glaucomatous eyes after treatment or filtering surgery. A. Incomplete peripheral iridectomy created by laser. B. Full-thickness peripheral iridectomy created by laser. C. Postoperative features of trabeculectomy including peripheral iridectomy, inner scleral defect, thin residual scleral flap, and overlying conjunctival filtering bleb. D. Tube shunt projecting radially into anterior chamber; note that the tube “shadows” deeper structures.