V Ashok Murthy, Santosh Bollineni
Department of ENT, PES Institute of Medical Science and Research, Kuppam, 517 425 India.
Indian J Otolaryngol Head Neck Surg. 2017 Dec;69(4):514-522. doi: 10.1007/s12070-017-1229-8. Epub 2017 Nov 7.
The endoscope has revolutionized the diagnosis and treatment of diseases of the nose and paranasal sinuses. Endoscopic sinus surgery (ESS), like all minimally invasive surgery, is designed to combine an excellent outcome with minimal patient discomfort. Successful outcome with minimal complications can only be achieved with good knowledge of the endoscopic anatomy, appropriate training in the procedure and the understanding of the anatomical variations. The intraoperative complications of ESS are bleeding and injury to surrounding structures commonly the orbital structures and fovea ethmoidalis. This is a hospital based prospective observational study with an objective to define the distribution of Keros classification of the depth of olfactory fossa and its asymmetrical distribution rates based on Keros type. Prospective study in a tertiary rural based hospital. 100 patients above the age of 10 years from October 2013 to March 2015 for a period of one year six months undergoing endoscopic sinus surgery in the Department of ENT, P.E.S. Institute of Medical Sciences and Research, Kuppam were chosen randomly. The data was collected from these patients who will met the inclusion criteria of the study and before undergoing endoscopic sinus surgery by subjecting them to CT scan of paranasal sinuses. It is observed that a total of 100 patients had been studied in which the mean age of the population is 36.65 + 13.36 years. Youngest patient was 12 years old and eldest patient was 70 years old. Among the patients 50(50%) were males and remaining 50(50%) were females with a female to male ratio is 1:1. In the present study, the depth of olfactory fossa ranged from 2.1 to 8.3 mm inclusive of both sides in 200 CT images with a mean height of 5.21 mm. Of the 200 sides measured, the distribution of Keros classification is as the following-Keros type I 39(19.5%), Keros type II 143(71.5%) and Keros type III 18(9%) sides. Based on these observations, type II is the most common Keros type prevalent followed by type 1 Keros type and the least prevalent is the type III Keros type in the studied population. In the present study, on considering sides separately, the right side olfactory fossa depth ranged from 2.1 to 8.3 mm with a mean height of 5.43 mm and the left side olfactory fossa depth ranged from 2.1 to 8.1 mm with a mean height of 4.98 mm. On the right side, of 100 sides measured, the distribution of Keros classification is as the following-Keros type I 19(19%), Keros type II 68(68%) and Keros type III 13(13%) sides. On the left side, of 100 sides measured, the distribution of Keros classification is as the following-Keros type I 25(25%), Keros type II 70(70%) and Keros type III 5(5%) sides. Based on these observations, type II is the most common Keros type prevalent followed by type 1 Keros type and the least prevalent is the type III Keros type in the studied population on both sides. In the present study, out of 100 patients 23 patients were having asymmetric olfactory fossa between right and left sides based on Keros type, where as remaining 77% had symmetric Keros type on right and left sides. Out of 23 patients, 16 patients were having lower or deep olfactory fossa on right side, where as remaining 7 patients were having lower or deep olfactory fossa on left side. Based on these observations, a lower or deep ethmoid roof occurred more frequently on the right side than on the left side. Wilcoxon matched pair signed rank test is applied to see the significant difference between depth of right and left olfactory fossae. Since value is < 0.001 the depth of olfactory fossa is significantly different from each other. The present study presents a precise, quantitative analysis of the olfactory fossa and ethmoid roof position as well as individual asymmetry. This information may be useful during pre-operative evaluation of CT images, as well as intraoperatively. The surgeon's understanding of the anatomy of a patient's ethmoid roof and its possible variations is crucial for countering possible complication risks during endoscopic sinus surgery.
内窥镜彻底改变了鼻和鼻窦疾病的诊断与治疗方式。内窥镜鼻窦手术（ESS）与所有微创手术一样，旨在实现良好的治疗效果并使患者不适降至最低。只有充分了解内窥镜解剖结构、接受适当的手术培训并理解解剖变异，才能取得并发症最少的成功治疗效果。ESS的术中并发症包括出血以及对周围结构（通常是眼眶结构和筛骨水平部）的损伤。这是一项基于医院的前瞻性观察研究，目的是确定基于Keros分型的嗅窝深度的分布情况及其不对称分布率。在一家三级农村医院进行前瞻性研究。随机选择2013年10月至2015年3月期间在库帕姆的PES医学科学与研究所耳鼻喉科接受内窥镜鼻窦手术的100名10岁以上患者，为期一年零六个月。从符合研究纳入标准的这些患者中收集数据，并在他们接受内窥镜鼻窦手术前对其进行鼻窦CT扫描。观察发现，总共研究了100名患者，人群平均年龄为36.65±13.36岁。最年轻的患者为12岁，最年长的患者为70岁。患者中50名（50%）为男性，其余50名（50%）为女性，男女比例为1:1。在本研究中，200张CT图像中双侧嗅窝深度范围为2.1至8.3毫米，平均高度为5.21毫米。在测量的200侧中，Keros分型分布如下：Keros I型39侧（19.5%），Keros II型143侧（71.5%），Keros III型18侧（9%）。基于这些观察结果，在研究人群中，II型是最常见的Keros类型，其次是I型，最不常见的是III型。在本研究中，分别考虑两侧时，右侧嗅窝深度范围为2.1至8.3毫米，平均高度为5.43毫米，左侧嗅窝深度范围为2.1至8.1毫米，平均高度为4.98毫米。在右侧测量的100侧中，Keros分型分布如下：Keros I型19侧（19%），Keros II型68侧（68%），Keros III型13侧（13%）。在左侧测量的100侧中，Keros分型分布如下：Keros I型25侧（25%），Keros II型70侧（70%），Keros III型5侧（5%）。基于这些观察结果，在两侧的研究人群中，II型是最常见的Keros类型，其次是I型，最不常见的是III型。在本研究中，100名患者中有23名患者基于Keros分型两侧嗅窝不对称，其余77%的患者两侧Keros分型对称。在23名患者中，16名患者右侧嗅窝较低或较深，其余7名患者左侧嗅窝较低或较深。基于这些观察结果，筛骨顶较低或较深在右侧比在左侧更常见。应用Wilcoxon配对符号秩检验来观察左右嗅窝深度之间的显著差异。由于p值<0.001，嗅窝深度彼此之间存在显著差异。本研究对嗅窝和筛骨顶位置以及个体不对称性进行了精确的定量分析。这些信息在术前CT图像评估以及术中可能会有用。外科医生对患者筛骨顶解剖结构及其可能变异的了解对于应对内窥镜鼻窦手术中可能的并发症风险至关重要。
