Importance of Keros Classification in Surgery
DOI:
https://doi.org/10.17140/OTLOJ-3-143Keywords:
Keros classification, Ethmoid roof, Paranasal Sinus, Cribriform plateAbstract
Objective: The relationship between the cribriform plate and the uncinate process may be elaborated with the help of the Keros classification. The observations were analysed using high-resolution computed tomography (HRCT). Additionally, the relationship between the superior attachment of the uncinate process, the existence of concha bullosa, and the different types of ethmoid roofs were examined.
Methods: Five-hundred and sixteen subjects complaining of sinonasal disorders between 2015 and 2016 were enrolled retrospectively at the Okmeydani Training and Research Hospital, Department of Otolaryngology. HRCT scans of 1-mm sections were obtained. Keros classification was used for the measurement of the depth of the olfactory fossa as follows: Keros I: 1-3 mm, Keros II: 3-7 mm, and Keros III: 7-16 mm.
Results: Fifty-one point nine percentage of cases were of Keros type II, 27.7% of type III, and 20.3% of type I. In 82.4% of the reported cases, the uncinate process was attached to the lamina papyraceae, in 11% of the cases it was attached to the middle nasal turbinate, and in 6.4% cases to the skull base. A concha bullosa was observed in the right nasal cavity in 13.8% of the cases, in the left nasal cavity in 11% of the cases, and bilaterally in 16.3% of the cases. Variances observed in the Keros types were not statistically significant with respect to sex (p>0.05). Concha bullosa was significantly more frequently seen in females (53.1%) relative to males (p=0.001). Conclusion: Endoscopic sinus surgery (ESS) is the primary mode of treatment for chronic sinus diseases. In this procedure, a proper assessment of the vital structures is very important to avoid further complications. In the present study, it has been suggested that determining the depth of the ethmoid roof is necessary to avoid injuring the bony lamella, which can lead to cerebrospinal fluid rhinorrhea.
References
Zacharek MA, Han JK, Allen R, et al. Sagital and coronal dimensions of the ethmoid roof: A radioanatomic study. Am J Rhinol. 2005; 19: 348-352.
Luong A, Marple BF. Sinus surgery: Indications and tech-niques. Clin Rev Allergy Immunol. 2006; 30: 217-222.
Ohnishi T, Tachibana T, Kaneko Y, Esaki S. High-risk areas in endoscopic sinus surgery and prevention of complications. Laryngoscope. 1993; 103: 1181-1185. doi: 10.1288/00005537- 199310000-00020
Leunig A, Betz CS, Sommer B, Sommer F. Anatomic varia-tions of the sinuses; multiplanar CT-analysis in 641 patients. Laryngorhinootologie. 2008; 87: 482-489. doi: 10.1055/s-2007- 995572
Keros P. On the practical value of differences in the level of the lamina cribrosa of the ethmoid. Z Laryngol Rhinol Otol. 1962; 41: 809-813.
Zeinreich SJ. Paranasal sinus imaging. Otolaryngol Head Neck Surg. 1990; 103: 868-869. doi: 10.1177/01945998901030S505
Messerklinger W. On the drainage of the frontal sinus of man. Acta Otolaryngol. 1967; 63: 176-181. doi: 10.3109/00016 486709128748
Stammberger H. Endoscopic endonasal surgery-concepts in treatment of recurring rhinosinusitis. Part 1. Anatomik and pathophysiologic considerations. Otolaryngol Head Neck Surg. 1986; 94(2): 143-147. doi: 10.1177/019459988609400202
McMains KC. Safety in endoscopic sinus surgery. Curr Opin Otolaryngol Head Neck Surg. 2008; 16: 247-251. doi: 10.1097/ MOO.0b013e3282fdccad
Ulualp SO. Complications of endoscopic sinus surgery: Appropriate management of complications. Curr Opin Oto-laryngol Head Neck Surg. 2008; 16: 252-259. doi: 10.1097/ MOO.0b013e3282fdc3b2
Erdogan S, Keskin G, Topdag M, Ozturk M, Sari F, Mutlu F. Ethmoid roof radiology; analysis of lateral lamel-la of cribriform plate. Otolaryngol Pol. 2015; 69: 53-57. doi: 10.5604/00306657.1184543
Stammberger H, Posawetz W. Functional endoscopic sinus surgery. Concept, indications and results of Messerklinger tech-nique. Eur Arch Otorhinolaryngol. 19990: 247(2): 63-76.
Sheng YC, Chih JY, Chiao HL, et al. The association of su-perior attachment of uncinate process with pneumatization of middle turbinate: A computed tomographic analysis. Eur Arch Otorhinolaryngol. 2017; 274: 1905-1910. doi: 10.1007/s00405- 016-4441-3
Bolger WE, Butzin CA, Parsons DS. Paranasal sinus bony anatomic variations and mucosal abnormalities: CT analysis for endoscopic sinus surgery. Laryngoscope. 1991; 101: 56-64. doi: 10.1288/00005537-199101000-00010
Perez-Piñas I, Sabaté J, Carmona A, Catalina-Herrera CJ, Jiménez-Castellanos J. Anatomical variations in the human pa-ranasal sinus region studied by CT. J Anat. 2000; 197: 221-227. doi: 10.1046/j.1469-7580.2000.19720221.x
Unlu HH, Akyar S, Caylan R, Nalça Y. Concha bullosa. J Otolaryngol. 1994; 23: 23-27.
Maru YK, Gupta Y. Concha bullosa: Frequency and appear-ances on sinonasal CT. Indian. J Otolaryngol Head Neck Surg. 1999; 52: 40-44. doi: 10.1007/BF02996431
Guldner C, Zimmermann AP, Diogo J, Werner JA, Tey-moortash A. Age-dependent differences of the anterior skull base. Int J Pediatr Otorhinolaryngol. 2012; 76(6): 822-828. doi: 10.1016/j.ijporl.2012.02.050
Elwany S, Medanni A, Eid M, Aly A, El-Daly A, Ammar SR. Radiological observations on the olfactory fossa and ethmoid roof. J Laryngol Otol. 2010; 124: 1251-1256. doi: 10.1017/ S0022215110001313
Ercan I, Cakir BO, Sayin I, Başak M, Turgut S. Relationship between the superior attachment type of uncinate process and presence of agger nasi cell: A computer-assisted anatomic study. Otolaryngol Head Neck Surg. 2006; 134: 1010-1014. doi: 10.1016/j.otohns.2006.01.021
Srivastava M, Tyag M. Role of Anatomic variations of uncinate process in frontal sinusitis. Indian J Otolaryngol Head Neck Surg. 2016; 68(4): 441-444. doi: 10.1007/s12070-015- 0932-6
Tuli IP, Sengupta S, Munjal S, Kesari SP, Chakraborty S. Anatomical variations of uncinate process observed in chronic sinusitis. Indian J Otolaryngol Head Neck Surg. 2013; 65(2): 157-161. doi: 10.1007/s12070-012-0612-8
Downloads
Published
How to Cite
Issue
Section
License
This work is licensed under a Creative Commons Attribution 4.0 International License.
All content published in Otolaryngology (OOJ) is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0). This license allows anyone to copy, distribute, transmit, and adapt the work — including for commercial purposes — provided appropriate credit is given to the original author(s) and source.
