海綿静脈洞血栓症との鑑別が困難であった海綿静脈洞部硬膜動静脈瘻の1例―Paradoxical worseningから自然治癒に至るまでの経時的血管撮影所見の変化

Paradoxical Worsening of Cavernous Sinus Dural Arteriovenous Fistula : Case Report with Serial Angiograms

Ⅰ．はじめに

　海綿静脈洞部硬膜動静脈瘻　cavernous sinus dural arteriovenous fistula（CavDAVF）は静脈洞の血栓化により自然閉塞することがあり，それに伴い臨床症状も改善，あるいは治癒することが一般的である．その一方で，CavDAVFが閉塞しているにもかかわらず一時的に眼症状を中心とした臨床症状が悪化するparadoxical worseningという現象が知られているが，その症例報告数はあまり多くなく，正確な病態生理については不明な点も多い^1,6-8)．

　われわれは特異な血行動態とparadoxical worseningのために海綿静脈洞血栓症との鑑別が困難であったCavDAVFの症例を経験し，自然治癒を確認するまで複数回血管撮影を施行し得た．本症例の臨床経過と経時的血管撮影所見の変化はparadoxical worseningの病態生理を理解するうえで有用であると思われたので報告する．

We report,with serial angiograms,a case worsening of dural arteriovenous fistulae (DAVFs) located at the hypoplastic right cavernous sinus and draining into the left superior ophthalmic vein across the inter-cavernous sinus. The patient presented with sudden onset of external ophthalmoplegia and deterioration of visual acuity on the left. An imaging work-up at the day of admission included contrast-enhanced computed tomography and conventional catheter angiography,which demonstrated complete thrombosis of the left cavernous sinus. There was no strong evidence to suggest DAVFs other than small faint opacification of the posterior cavernous sinus on the right at the late arterial phase. For this reason a diagnosis of left cavernous sinus thrombosis was made,followed by aggressive anticoagulation therapy with intravenous administration of antibiotics. Although the patient's eye symptoms improved significantly after the anticoagulation therapy,the follow-up angiogram obtained 5 days after admission demonstrated small right cavernous sinus DAVFs,which drained into the left superior ophthalmic vein. The patient was followed up conservatively at the out-patient clinic. Three-month follow up angiograms demonstrated spontaneous cure of the DAVF. Also noted was a complete recovery of external ophthalmoplegia with significant improvement of left visual acuity. The alternation of clinical and angiographic findings in this case may help to understand the etiology of paradoxical worsening of cavernous sinus DAVF. In selected cases,anticoagulation therapy may help to improve the prognosis of paradoxical worsening.