title: Stenting at the flow-limiting segment in tracheobronchial stenosis due to lung cancer.
abstract: Airway stenting at the wave-speed flow-limiting segment (the choke point) is assessed. We determined prospectively the precise location of the choke point using the flow-volume curve, endobronchial ultrasonography, ultrathin bronchoscopy, and three-dimensional computed tomography scan before and after stenting in 64 patients with extrincic compression due to lung cancer. We noted distinct flow-volume curve patterns specific to the type of stenosis. The tracheal stenosis group indicated fixed narrowing patterns with an expiratory plateau, bronchial stenosis group dynamic collapse patterns with an expiratory flow deterioration (choking), carinal stenosis group combined fixed and dynamic patterns, and extensive stenosis group complex patterns containing elements of all the former. After stenting, almost full-function patterns with significant improvement in PEF were observed in all groups (p < 0.01, p < 0.05, p < 0.001, p < 0.01, respectively). In patients with extensive stenosis, implantation of additional stents was required when the choke points were observed to have migrated to the areas of malacia with cartilage destruction by the tumor. Secondary stenting at migrated choke points resulted in a significant improvement in PEF over the initial stenting (p < 0.01). Stenting at the choke point improved expiratory flow limitation by increasing the cross-sectional area, supporting the weakened airway wall and relieving dyspnea.
authors.affiliation: Department of Pulmonary Medicine, Hiroshima City Hospital, 7-33 Naka-Ku, Moto-machi, Hiroshima, Japan 730-8518. miyazawt@carrot.ocn.ne.jp
authors.forename: Teruomi
authors.initials: T
authors.lastname: Miyazawa
authors.forename: Yuka
authors.initials: Y
authors.lastname: Miyazu
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Iwamoto
authors.forename: Atsuko
authors.initials: A
authors.lastname: Ishida
authors.forename: Koji
authors.initials: K
authors.lastname: Kanoh
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Sumiyoshi
authors.forename: Masao
authors.initials: M
authors.lastname: Doi
authors.forename: Noriaki
authors.initials: N
authors.lastname: Kurimoto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000402:Airway Obstruction / Q000175:diagnosis* / Q000401:mortality / Q000628:therapy*; D001982:Bronchial Diseases / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D001999:Bronchoscopy / Q000379:methods*; D002423:Cause of Death; D015331:Cohort Studies; D003251:Constriction, Pathologic; D019160:Endosonography / Q000379:methods; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D013147:Spirometry; D015607:Stents; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D014135:Tracheal Stenosis / Q000175:diagnosis / Q000401:mortality / Q000628:therapy; D016896:Treatment Outcome