Indirect carotid–cavernous sinus fistula following mechanical thrombectomy: A case report of a rare iatrogenic injury with progressive presentation

INTRODUCTION: With the increasingly common operation of mechanical thrombectomy (MT) in acute cerebral infarction cases, iatrogenic CCFs were occasionally reported. All of cases reported type A CCFs, and patients were presented with either asymptom from generation of fistula to duration of postoperative follow-up or distinct presentations at once after MT. CASE PRESENTATION: A 48-year-old postmenopausal female, without history of systemic hypertension and diabetes mellitus, underwent an operation of MT outside our institution about half a year ago. An intraoperative DSA showed an iatrogenic low-flow fistula between meningohypophyseal trunk and ICA. After 4 mouths' postoperative conservative observation, patient's presentation progressed from asymptom to serious optic signs. The patient underwent trans-arterial interventional occlusion. On postoperative day one, visual presentations of patient relieved significantly. DISCUSSION: We discuss the reason for possibility of iatrogenic injury to meningohypophyseal trunk and clinical progressive presentation. A sudden swerve just beyond derivation of meningohypophyseal trunk is prone to being damaged by a misguided guide wire. The progression of clinical presentation, as a focal point in our case, is not reported in iatrogenic before, but some studys still find that spontaneous dural CCFs are inclined to occur in middle-aged or elderly women, especially in postmenopausal women, so age and sex are regarded as background factors of progressing. In addition, the change of drainage route is an immediate cause of progressive presentations. CONCLUSION: We expect that when a manipulation of MT is conducted leading an iatrogenic CCF, our neurointerventionist should maintain appropriate vigilance on sex, age, menstrual history and medical history, then take an earlier and timely interventional measure.