title: CHESS classification of bladder-outflow obstruction. A consequence in the discussion of current concepts.
abstract: The present discussion on the natural history, growth rate pathophysiology, morbidity, and possible treatment of benign prostatic hyperplasia (BPH) reinforces the need to objectify mechanical BPH-induced obstruction with pressure-flow study. Different methods for the quantification of BPH-induced obstruction exist and the grade of simplification depends on their working mechanism. To review the limitations of the current concepts, 118 BPH patients were selected for computerized pressure-flow data analysis according to quadratic passive urethral resistance relation (PURR) function. The CHESS classification differs from all other concepts due to its two-dimensional character and was developed as a result of the following way of thinking: (1) the whole individual pressure-flow plot is the most accurate basis for further analysis; (2) PURR as the true low-pressure flank of the individual plot is the most favorable definition for mechanical obstruction; (3) PURR quantification requires at least two parameters, footpoint and curvature/slope, with regard to the documented missing significant correlation of both; and (4) a two-parameter-based classification is two-dimensional (CHESS classification).
authors.affiliation: Department of Urology, Hannover Medical School, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Höfner
authors.forename: A E
authors.initials: AE
authors.lastname: Kramer
authors.forename: H K
authors.initials: HK
authors.lastname: Tan
authors.forename: H
authors.initials: H
authors.lastname: Krah
authors.forename: U
authors.initials: U
authors.lastname: Jonas
mesh_terms: D000368:Aged; D006801:Humans; D008297:Male; D011470:Prostatic Hyperplasia / Q000150:complications / Q000503:physiopathology / Q000628:therapy; D001748:Urinary Bladder Neck Obstruction / Q000145:classification* / Q000209:etiology; D014563:Urodynamics / Q000502:physiology