Structural characteristics of septal cartilage and mucoperichondrium F AKSOY 1 , Y S YILDIRIM 2 , H DEMIRHAN 3 , O ÖZTURAN 1 , S SOLAKOGLU 4 Departments of Otorhinolaryngology and Head and Neck Surgery, 1 Medical Faculty, Bezmialem Vakif University, Istanbul, 2 Elbistan State Hospital, Kahramanmaras ¸, and 3 Haseki Research and Training Hospital, Istanbul, and 4 Department of Histology and Embryology, Faculty of Medicine, Istanbul University, Turkey Abstract Aim: During nasal septum surgery, elevation of mucoperichondrium from the anterior nasal septum may be more difficult than from the medial and posterior septum. This study aimed to evaluate any histological structural differences between the anterior and posterior nasal septum cartilage, mucoperichondrium and intervening tissue. Material and method: Unilateral mucoperichondrial flap elevation without infiltration was performed, after nasal tip and dorsum decortication, in four patients undergoing open septorhinoplasty. Full-thickness samples, including cartilage and mucoperichondrium, were removed from the anterior and posterior nasal septum and examined under light and electron microscopy. Results: Light microscopy showed no difference between anterior and posterior septum specimens regarding perichondrial thickness and subperichondrial cell density. Demarcation between cartilage and perichondrium and between perichondrium and lamina propria was more regular in the posterior versus the anterior septum. Electron microscopy showed no difference in chondroblast activity at the two sites. Conclusion: The observed tissue demarcation irregularities may explain the greater reported difficulty in elevating anterior versus posterior nasal septum mucoperichondrium. Immunohistochemical examination would further elucidate these interstructural connections. Key words: Nasal Septum; Histology; Septoplasty, Human Introduction Septal surgery is one of the most common surgical pro- cedures in otorhinolaryngological practice. It is per- formed either using an endonasal or an open technique. Both surgical approaches aim to remove and reconstruct the deviated parts, after mucoperichon- drial flap elevation. The nasal septum mucoperichondrium consists of four layers, as follows. The mucosal layer is outermost, and mostly consists of many stratified cells with or without cilia, goblet cells, and basal cells. The basal layer (also known as the submucosa-subepithelial con- nective tissue) consists of thick collagen fibres, and separates the epithelial layer from the lamina propria. The lamina propria (also known as the subepithelial connective tissue) consists of tubuloalveolar glands, capillary vessels and a venous plexus. The deepest layer is the perichondrium, which is composed of several layers of connective tissue fibres running paral- lel to the cartilage. 1 During septal surgery, the most appropriate approach is to perform mucoperichondrial flap elevation by dis- secting along the plane between the perichondrium (the innermost mucoperichondrial layer) and the cartilage. Dissection in this avascular area not only provides the surgeon with a bloodless surgical field with good visi- bility, but also reduces the risk of damage to the naso- palatine and incisive nerves and to specific structures such as the vomeronasal organ and submucosal organs. 2 Particular difficulty is often experienced when ele- vating mucoperichondrial flaps from the anterior nasal septum, compared with the posterior nasal septum. To our knowledge, no previous reports have investigated the reasons for this difficulty. The present study aimed to examine the histological structural characteristics of the nasal septum cartilage, mucoperichondrium and intervening layer, in both the anterior and posterior nasal septum, and to evaluate any differences, using light and electron microscopy. Presented at the Annual Conference in the 33rd Year of The European Academy of Facial Plastic Surgery, 1–5 September 2010, Antalya, Turkey Accepted for publication 3 May 2011 First published online 5 September 2011 The Journal of Laryngology & Otology (2012), 126, 38–42. MAIN ARTICLE © JLO (1984) Limited, 2011 doi:10.1017/S0022215111002404