眶壁较薄弱,其内有许多小的神经和血管,以及细小的裂缝(筛骨眶板裂),因此邻近鼻窦的感染容易蔓延至眼眶。感染性血栓性静脉炎感染了连接眼眶和鼻窦的无瓣膜静脉,接着感染蔓延至眼眶。[4]Chandler JR, Langenbrunner DJ, Stevens ER. The pathogenesis of orbital complications in acute sinusitis. Laryngoscope. 1970;80:1414-1428.http://www.ncbi.nlm.nih.gov/pubmed/5470225?tool=bestpractice.com[5]Kloek CE, Rubin PA. Role of inflammation in orbital cellulitis. Int Ophthalmol Clin. 2006;46:57-68.http://www.ncbi.nlm.nih.gov/pubmed/ 16770154?tool=bestpractice.com需要注意的是因眼眶内不存在淋巴管,故这种感染途径中并无淋巴的参与。
若眶周蜂窝织炎或眶蜂窝织炎的感染来源于鼻窦,最常见的来自于筛窦,正常情况下筛板可以将筛窦和眶内容物隔开,但如果筛窦存在炎症,感染往往可以通过薄薄的筛板蔓延至眼眶。少数情况下,感染也可通过额窦的下壁或上颌窦的上壁蔓延至眼眶。[6]Swift AC, Charlton G. Sinusitis and the acute orbit in children. J Laryngol Otol. 1990;104:213-216.http://www.ncbi.nlm.nih.gov/pubmed/2187942?tool=bestpractice.com[7]Howe L, Jones NS. Guidelines for the management of periorbital cellulitis/abscess. Clin Otolaryngol Allied Sci. 2004;29:725-728.http://www.ncbi.nlm.nih.gov/pubmed/15533168?tool=bestpractice.com[8]Wald ER, Pang D, Milmoe GJ, et al. Sinusitis and its complications in the pediatric patient. Pediatr Clin North Am. 1981;28:777-796.http://www.ncbi.nlm.nih.gov/pubmed/7312451?tool=bestpractice.com[9]Uzcategui N, Warman R, Smith A, et al. Clinical practice guidelines for the management of orbital cellulitis. J Pediatr Ophthalmol Strabismus. 1998;35:73-79.http://www.ncbi.nlm.nih.gov/pubmed/9559505?tool=bestpractice.com[10]Rumelt S, Rubin PA. Potential sources for orbital cellulitis. Int Ophthalmol Clin. 1996;36:207-221.http://www.ncbi.nlm.nih.gov/pubmed/8989612?tool=bestpractice.com上颌窦炎常继发于牙源性感染。
鼻窦炎导致静脉及淋巴回流障碍,继而引起眼睑水肿。眶蜂窝织炎的症状和体征(视力障碍、眼球突出和球结膜水肿)是由于炎性渗出物蔓延至眼眶,伴有眶内软组织水肿,导致眶内压增高引起的。[4]Chandler JR, Langenbrunner DJ, Stevens ER. The pathogenesis of orbital complications in acute sinusitis. Laryngoscope. 1970;80:1414-1428.http://www.ncbi.nlm.nih.gov/pubmed/5470225?tool=bestpractice.com