Apex-to-cupola distance following VATS predicts recurrence in patients with primary spontaneous pneumothorax

Our study sought to determine whether the size of the residual apical pleural space in young patients with primary spontaneous pneumothorax (PSP) following video-assisted thoracoscopic surgery is associated with the risk of recurrence. We retrospectively reviewed patients (<30 years' old) with primary spontaneous pneumothorax following thoracoscopic surgery (2002-2010) in a university-affiliated hospital. The size of residual apical pleural space was estimated by measuring the apex-to-cupola distance on a postoperative chest radiograph at 2 time windows: first between postoperative day (POD) 0 and 3, and second between POD 4 and 14. A total of 149 patients were enrolled with a median follow-up of 11.2 months (interquartile range, 0.95-29.5 months), of whom 141 (94.6%) were male with a mean age of 20 years. The postoperative recurrence rate was 11.4%. Comparing the characteristics between the patients with and without recurrent pneumothorax, the patients with recurrence were younger (18.2 + 2.4 vs 20.7 + 3.7 years, P = 0.008), with a lower rate of pleurodesis (35% vs1 69%, P = 0.037), longer apexto-cupola distance at POD 0 to 3 (22.41 ±19.56 vs 10.07 ± 10.83 mm, P<0.001) and POD 4 to 14 (11.82 + 9.75 vs 5.54 + 8.38mm, P = 0.005) than the patients without recurrence. In a multivariate logistic regression model for recurrent pneumothorax, age <18 years (P = 0.026, odds ratio [OR]: 4.694), apex-to-cupola distance at POD 0 to 3 >10mm (P = 0.027, OR: 5.319), and no pleurodesis during VATS (P = 0.022, OR: 5.042) were independent risk factors for recurrent pneumothorax. The recurrence rate was not low (11.4%) in young patients with PSP following VATS. Residual apical pleural space with apex-to-cupola distance of 10 mm or greater at POD 0 to 3, younger age, and no pleurodesis would increase postoperative recurrence of primary spontaneous pneumothorax.