title: Mitomycin-C concentration in human ocular aqueous humor after topical administration during trabeculectomy.
abstract: The concentration of the antitumor antibiotic mitomycin (CAS 50-07-7, mitomycin C, MMC), used in ophthalmic surgery for its antiproliferative effects, was measured in the aqueous humor of 7 glaucoma patients undergoing trabeculectomy. Sponges soaked with MMC-solution (100 microliters of MMC-solution 0.2 mg/ml: 20 micrograms) were applied intraoperatively on the scleral flap for 5 min. 100 to 200 microliters of aqueous humor were drawn with a needle 10 min following the end of topical MMC-treatment. Samples were assayed for MMC using a reverse-phase HPLC-system with ultraviolet detection (C18-column, elution: phosphate buffer (0.01 mol/l, pH: 6.5): methanol, v:v = 70:30, 365 nm). Swabs were extracted in phosphate-buffer (0.1 mol/l, pH: 7.0) before HPLC-analysis. External calibration was used for MMC quantitation. Quantitation limit was 10 ng/ml. In all aqueous humor samples MMC-concentration was below 10 ng/ml. MMC in the swabs amounted to 37% of the MMC amount applied.
  
  
  CONCLUSIONS
  After intraoperative topical application, the MMC concentration in the aqueous humor of patients is very low. The substantial loss of MMC from the swabs used for the topical MMC-treatment suggests 1. rapid systemic absorption of MMC and/or 2. a loss through irrigation of the operative field following topical MMC-application.
authors.affiliation: Institut für Pharmakologie, Universität Köln, Germany.
authors.forename: A F
authors.initials: AF
authors.lastname: Rump
authors.forename: W
authors.initials: W
authors.lastname: Biederbick
authors.forename: S
authors.initials: S
authors.lastname: Botvinik-Helling
authors.forename: M
authors.initials: M
authors.lastname: Stemmler
authors.forename: J
authors.initials: J
authors.lastname: Schierholz
authors.forename: S
authors.initials: S
authors.lastname: Conrady
authors.forename: B
authors.initials: B
authors.lastname: Matthey
authors.forename: M
authors.initials: M
authors.lastname: Theisohn
authors.forename: M
authors.initials: M
authors.lastname: Diestelhorst
authors.forename: G K
authors.initials: GK
authors.lastname: Krieglstein
mesh_terms: D000287:Administration, Topical; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001082:Aqueous Humor / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005901:Glaucoma / Q000378:metabolism / Q000601:surgery; D006801:Humans; D016685:Mitomycin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D013056:Spectrophotometry, Ultraviolet; D014130:Trabeculectomy
chemical_list: D000903:Antibiotics, Antineoplastic; D016685:Mitomycin