X-ray analysis of foramen rotundum for preliminary diagnosis of fossa pterygopalatina lesions

Abstract

Objectives: Fossa pterygopalatina is located posterior to maxillary sinus, anterior to pterygoid plates and inferior to greater

sphenoid wing. Tumors that arise in fossa pterygopalatina are usually asymptomatic and often discovered at late stage.

Because of its deep and relative inaccessible location, clinical examination of fossa pterygopalatina is difficult. Aplastic or

nonvisible foramen rotundum may give an early indication for the regional tumors.

Methods: In the present study, foramen rotundum was visualized as a round structure with prominent sclerotic margins located

near ethmoid cells, maxillary sinus or orbital cavity in X ray images. X-rays (radiographs) of 17 dry skulls and 7 half dry skulls

were performed with Phillips Digital Diagnost X-Ray device. All dry skulls were positioned similar to Caldwell’s view. We have

designed a fixation apparatus to optimize the positioning of dry skulls and half skulls. After fixation of the skulls with the apparatus,

the X-ray beam centered about 3–4 cm below the external occipital protuberance with an angle of 15 degrees to the

chantomeatal line. Each radiologic image was examined for the location of foramen rotundum in relation with orbital cavity, ethmoidal

cells and maxillary sinuses. We described the characteristic of foramen rotundum with count and percent values.

Results: In the present study, 41 foramina rotunda were analyzed. Out of 41 foramina rotunda, twenty were right-sided, twenty

one were left-sided. Of the 20 right-sided foramina rotunda, 19 were visible on X-ray images. On the other side 18 of 21 leftsided

foramina rotunda were apparent. 14 of 19 visible right-sided foramina rotunda were identified in the orbital cavity

(73.68%). Three of them were identified in ethmoidal cells, and two in the maxillary sinus. 11 of 18 visible left-sided foramina

rotunda were identified in the orbital cavity (61.11%). Two of these were found in ethmoidal cells, eight in the maxillary sinus.

Out of 17 dry skulls, one had bilateral nonvisible foramina rotunda.

Conclusion: Foramen rotundum must be taken into consideration in evaluation of routine X-rays to prevent misdiagnosis of

the patients with persistent non-specific symptoms.

Keywords

• foramen rotundum,pterygopalatine fossa,cranium,X-ray

References

1. Referans1 DelGaudio JM. Endoscopic Transnasal Approach to the Pterygopalatine Fossa. Arch Otolaryngol Head Neck Surg.2003;129:441-446
2. Referans2 Xue T , Yang W , Guo Y , Yuan W , Dai J , Zhao Z . 3D Image-Guided Percutaneous Radiofrequency Thermocoagulation of the Maxillary Branch of the Trigeminal Nerve Through Foramen Rotundum for the Treatment of Trigeminal Neuralgia. Medicine (Baltimore). 2015 Nov; 94(45): e1954.
3. Referans3 Ordones A.B, Fornazieri M.A, Pinna F.R, Bezerra T.F.P, R.L.Voegels, Sennes L. U.Transpterygoid Approach to a Dermoid Cyst in Pterygopalatine Fossa. Int Arch Otorhinolaryngol. 2014 Jan; 18(1): 83–86.
4. Referans4 Cheng Y, Xu H, Chen Y, Xu S, Yu H, Zhang S, Feng Y, Zhao G. Location of Pterygopalatine Fossa and its Relationships to the Structures in Sellar Region. The Journal of Craniofacial Surgery 2015 Sep;1049-2275 Doi: 10.1097/SCS.0000000000001899
5. Referans5 Lee E.J, Jung S.L, Kim B.S, Kook Jin Ahn K.J, Kim Y.J, Jung A.K, Park C.S, Song S.Y, Park N.H, Kim M.S. MR Imaging of Orbital Inflammatory Pseudotumors with Extraorbital Extension. Korean J Radiol. 2005 Apr-Jun; 6(2): 82–88.
6. Referans6 Zhou H, Xing G, Gao X, Wang J, Chen F, Lu L, Zhang Y, Chen Z, Qian X. Schwannoma of the Sinonasal Tract and the Pterygopalatine Fossa with or without Intracranial Extension. ORL 2015;77:61–69
7. Referans7 Choudhri A.F, Patel R.M, Wilroy R.S, Pivnick E.K, Whitehead M.T. Trigeminal Nerve Agenesis with Absence of Foramina Rotunda in Go´mez–Lo´pez–Herna´ndez Syndrome. Am J Med Genet Part A 167A:238–242.