adenoid cystic carcinoma ( acc ) is a malignant tumor characterized by perineural invasion , slow growth , and insidious destruction of surrounding tissues . it usually arises in the major salivary gland , but also in minor salivary gland occasionally . acc arising in the pterygopalatine fossa is extremely rare , only 3 cases have been reported . in these cases , 1 patient presented visual deficit because of neural invasion . owing to its proximity to the superior orbital fissure and optic canal , neoplasms arising in the pterygopalatine fossa may cause optic neuropathy by direct invasion or oncothlipsis . current literature has described possible visual recovery following excision of anterior clinoid mucocele , but few authors reported whether the visual deficit could be resolved after the resection of the tumor arising in the pterygopalatine fossa . in current study , we described 1 patient with visual dysfunction induced by acc arising in the pterygopalatine fossa . the zhengzhou university institutional research committee approved our study , and the participant signed an informed consent agreement . a 44-year - old chinese man presented a mass in the palate for 7 months , there was no ulcer or pain . one month ago , the visual acuity of the right eye dropped gradually and then there was no vision at diagnosis . preoperative radiographs presented a huge mass in the pterygopalatine fossa and infratemporal fossa ( figure 1a ) , but we could not determine whether the optic nerve was invaded ( figure 1b ) . after explaining the possible risks including total blindness to the patient , a surgical plan was formulated . and the patient reported the visual acuity had returned to normal at 10 days after the operation . at 2 months after discharge from the hospital , there was no recurrence of the tumor ( figure 1c ) , and the patient was satisfied with the appearance and the functional results . ( a ) huge space - occupying lesion in the pterygopalatine fossa and infratemporal fossa was noted . ( b ) the tumor involved the orbital apex , but the association between the optic nerve and the tumor could not be justified clearly . ( c ) at 2 months after discharge from the hospital , there was no recurrence of the tumor . the most distinctive biological behavior of acc was perineural spread . in previous case reports , all these findings supported the above - mentioned viewpoint . in current study , optic dysfunction was also noted , but it would be contributed by external compression rather than direct tumor invasion . various surgical approaches for the pterygopalatine fossa and infratemporal fossa have been advocated . it could be divided into 3 groups inferior approach , lateral approach , and anterior approach . inferior approach could not provide adequate exposure of the retromaxillary and the skull base , and it was usually suggested for the tumor restricted in the parapharyngeal space . lateral approach was limited for tumors extending medial to the pterygomaxillary fissure and especially those stretching across the medline . the maxillary swing approach was first introduced by wei et al for recurrent nasopharyngeal carcinoma as a novel anterior approach . nowadays , the route has been the preferable approach for tumors arising in the pterygopalatine fossa and infratemporal fossa . compared to the facial translocation approach , the maxillary swing approach did not require neurorraphy and could avoid the development of a free facial graft by keeping the anterior maxilla and translocated hard palate attached to the cheek flap . in current study , possible postoperative complications such as palatal fistula , epiphora , and trismus have been reported . the most interesting finding in such case was complete recovery of visual disorder following surgical resection of the disease . suri et al have studied the visual outcome in patients with suprasellar tumors who experienced preoperative blindness , and the authors found male sex , shorter duration of blindness , operative evidence of hemorrhage in tumor , and soft tumor consistency were significantly associated with the visual outcome ; another research conducted by mathiesen et al presented early optic nerve decompression and primary tumors seemed to predict better visual prognosis . similarly , kitano et al compared postoperative improvement of visual function among different approaches in treating suprasellar meningiomas , and the authors found extended transsphenoidal approach might resulted in improvements in visual acuity . other associated factors , such as the size of mass , the pathology type , tumor consistency and , so on , have also been proven in the literature . the same principle might also be compliant to the present case . in summary , acc arising in the pterygopalatine fossa visual loss contributed by the tumor in the pterygopalatine fossa could recover in selected patients .