Chong V F, Fan Y F, Khoo J B, Lim T A
Department of Diagnostic Radiology, Singapore General Hospital.
Ann Acad Med Singap. 1995 May;24(3):436-41.
In a prospective study comparing computed tomography (CT) and magnetic resonance imaging (MRI) in the staging of nasopharyngeal carcinoma (NPC), 17 (15%) patients were noted to have infiltration of the pterygopalatine fossa (PPF). The recognition of PPF abnormalities depends on the familiarity of the normal anatomy. CT and MRI appearances of the normal PPF in the remaining 97 (85%) patients were reviewed. The fossae were symmetrical and fat was seen in all MRI and in 95% of the CT scans. There was destruction of the pterygoid process in 10 (9%) patients and a further 10 patients showed erosion of the maxillary sinus. Superior infiltration from the PPF into the inferior orbital fissure was demonstrated in 7 (6%) patients. Lateral spread via the pterygopalatine fissure into the infratemporal fossa could be seen in 10 (9%) patients. The earliest indication of tumour infiltration of the PPF is the replacement of the normal fat content. Widening of the fossa and erosion of the bony margins are late signs. As expected, bony abnormality is best seen on CT. However, direct visualisation of tumour or replacement of fat is more elegantly demonstrated on T1-weighted MRI.
在一项比较计算机断层扫描（CT）和磁共振成像（MRI）在鼻咽癌（NPC）分期中的前瞻性研究中，发现17例（15%）患者存在翼腭窝（PPF）浸润。对PPF异常的识别取决于对正常解剖结构的熟悉程度。回顾了其余97例（85%）患者正常PPF的CT和MRI表现。这些窝是对称的，在所有MRI检查以及95%的CT扫描中均可见脂肪。10例（9%）患者存在翼突破坏，另有10例患者显示上颌窦侵蚀。7例（6%）患者显示PPF向上浸润至眶下裂。10例（9%）患者可见通过翼腭裂向颞下窝的外侧扩散。PPF肿瘤浸润的最早迹象是正常脂肪成分被取代。窝增宽和骨边缘侵蚀是晚期征象。正如预期的那样，骨异常在CT上显示最佳。然而，在T1加权MRI上能更清晰地直接显示肿瘤或脂肪被取代的情况。
