Patent ID: 8496006

Claim:
A method for reducing the residual volume of a hyperinflated lung compartment, said method comprising: sealing a distal end of a catheter in an airway feeding the lung compartment by using an occluding member that is adapted to be expanded in an airway which feeds the hyperinflated lung compartment such that access to the compartment is provided only through a passage of the catheter when the occluding member is expanded; allowing air to be expelled from the lung compartment through the passage in the catheter while the patient is exhaling; blocking air from entering the lung compartment through the catheter passage while the patient is inhaling by using a one-way flow element adapted to be disposed within or in-line with the passage of the catheter so that flow in a distal-to-proximal direction is allowed and flow in a proximal-to-distal direction is inhibited or prevented; and determining whether collateral ventilation is present in the lung compartment, wherein determining whether collateral ventilation is present comprises detecting, using a flow-measuring device, air flow or accumulation from the isolated lung compartment over time; calculating, using a computer, a value of collateral resistance; and diagnosing collateral ventilation between the target lung compartment and at least one adjacent lung compartment based on the value of collateral resistance calculated by the computer.