In advanced emphysema, the lungs become progressively enlarged. Researchers have long tried to find ways to reduce lung volume and improve airflow without risky surgery. Now, three promising techniques are in or near clinical testing at Temple University and other medical centers. "They all have pluses and minuses," said Temple pulmonologist Gerard J. Criner, a leading emphysema researcher. "I foresee a day where a patient would have several of these techniques, based on their anatomy."