How many lobes do you see?

Accessory fissures of the lung represent common variations of lung specimens. Several accessory fissures have been well described in time by the anatomists [1]. Accessory fissures can be described anatomically as clefts of various depth composed by two layers of visceral pleura. They may be complete or incomplete differentiating a part of lung which is termed as an accessory lobe. They are more frequently encountered in fetal and neonatal lung specimens compared to adult ones [1]. Accessory fissures often go unappreciated or misinterpreted on plain x-ray films and computed tomographic (CT) scans [2].A 19-year old male patient was admitted to our department suffering from recurrent spontaneous right side pneumothorax. After the insertion of the chest tube the lung reexpanded fully. Imaging of the chest revealed extended bullous disease, therefore the patient was offered the choice of surgical treatment. During the thoracotomy we discovered an interesting anatomic variation of the right lung. More specifically, the superior segment of the right lower lobe appeared separated from its native lobe through an extra fissure (Figure 1), thus giving the whole lung the image of a four lobed one. This finding was not visible in the preoperative CT (Figure 2) or plain x-ray films probably due to the patient's bullous disease. Despite the fact that thoracoscopic approach for primary spontaneous pneumothorax is considered to be the treatment of choice [3], in our case the large size of the bullae led the surgical team to avoid a VATS procedure. The patient finally underwent apical bullectomy along with partial parietal pleurectomy and chemical pleurodesis. This unique finding did not hinder the operation which was performed without any complications and the patient recovered uneventfully.Supernumerary fissures are commonly encountered as variations of the lungs. On conventional CT examinations, these fissures are demonstrated infrequently due to inappropriate slice thickness, inc