Discussion
In this case, we selected a combination of revascularization and skull base reconstruction. Previously reported ICA rupture cases due to osteonecrosis were almost recurrent NPC cases, and probably no long-term prognosis could be expected [1,2,6,8-10]. In contrast, the primary disease as pituitary adenoma had been stable for a long time. Therefore, complications after long period of time, such as left ICA rupture, should be considered when necrotic tissue on the sphenoid bone was not removed. Hence, we considered that if complete revascularization had been established, skull base reconstruction with removal of necrotic tissue would be also necessary to prevent complications for a long time.
Osteoradionecrosis, resulting from a second course of radiotherapy, affected the right ICA rupture, which might have been caused by obstruction of the vasa vasorum, premature atherosclerosis, adventitial fibrosis, and necrosis of the arterial wall [2,7,11]. Although cases in previous reports typically were accompanied by a pseudoaneurysm [1,2,6-11], it was not noticeable on conventional angiography in the current case. Therefore, even with a massive epistaxis, it was difficult to immediately diagnose the patient with right ICA rupture based only on angiography results. However, considering the progress of follow-up from the first visit, it was strongly suggested that epistaxis was caused by right ICA rupture.
We selected revascularization using high-flow bypass with trapping of the right ICA. Most authors have argued that endovascular treatment should be the first choice for ICA rupture with pseudoaneurysm in situations where patients could tolerate BOT [1,2,6-11]. The success rate was 87% of endovascular treatment and 33% of high-flow bypass according to a previous study [1]. However, this case was a peculiar situation in which it was difficult to evaluate BOT. The patient had impaired consciousness at the time of the conventional angiography. In addition, prerequisites for endovascular treatment could not be identified because there were no findings of pseudoaneurysm or the site of hemorrhage could be determined. Consequently, revascularization was performed instead of endovascular treatment. In addition, revascularization greatly reduced the risk of hemorrhage from the right ICA during skull base reconstruction. Therefore, surgical manipulations could be performed safely.
This combination procedure in the current case has some limitations. High-flow bypass with RA grafting is technically dependent, especially in emergency situations [1,10]. Additionally, it is necessary to urgently assemble a cross-departmental team of otolaryngologists and neurosurgeons: neurosurgeon-otolaryngologist collaboration. Nevertheless, to rescue this type of cases and obtain the best results, the combination procedure we performed would be a definitive curative treatment.