A
42 year old woman who had 3 episodes of diplopia since summer 2005, with the
last one in late November 2006. Each of these lasted for approximately 1
month. The first two episodes were accompanied with dizziness, nausea and
some headache. After the first episode, which was treated with
corticosteroids, she was diagnosed to have MS and was put on interferon
injections based on MRI findings of unspecified white matter lesions seen on T2
images without enhancement. In March 2006 during her second episode which
she developed while on treatment with interferon her clinical status was
characterized by pure diplopia on looking to the left and up without any other
signs or symptoms and the patient resolved on steroids again. At this time she
visited me and I ordered VEP, BEVP, and SEP which came back normal. Also a
repeat MRI showed exactly the same findings as the previous one. As she
was free of symptoms I suggested stopping interferon treatment and ordered
additional investigations. She stopped interferon but didn’t came back
for more tests until the third episode with pure diplopia of the same type which
resolved by Christmas without any steroids. Anti-Ach receptor antibodies
were negative. Her past history is remarkable only for migraine headaches.
Now
she is in perfect condition.
The MRA found a persistent primitive trigeminal artery(PPTA) on the left side which according to the radiologist can rarely cause VI cranial palsy. I have to mention that the patient had diplopia mostly on left lateral gaze ( both by hx & exam).
I found some references in Pubmed about ppta and diplopia but it is only in coexistence with aneurysm or carotid-cavernous fistulas.
1)Merry GS, Jamieson KG. Operative approach to persistent trigeminal artery producing facial pain and diplopia. Case report.
J Neurosurg. 1977 Oct;47(4):613-8.A case is reported of persistent trigeminal artery producing intermittent facial pain, the last episode being associated with diplopia. The trigeminal and abducent nerves were attached to the trigeminal artery by a congenital membrane. Blood supply to the vertebrobasilar system was via the persistent vessel. A new operative approach along the petrous-temporal ridge is described.
2)Hurst RW, Howard RS, Zager. Carotid cavernous fistula associated with persistent trigeminal artery: endovascular treatment using coil embolization. Skull Base Surg. 1998;8(4):225-8. Links
3)Kawasaki A, Purvin V. Isolated IVth (trochlear) nerve palsy due to basilar artery dolichoectasia. Klin Monatsbl Augenheilkd. 2006 May;223(5):459-61.
4)Tokunaga K, Sugiu K, Kameda M, Sakai K, Terasaka K, Higashi T, Date I. Persistent primitive trigeminal artery-cavernous sinus fistula with intracerebral hemorrhage: endovascular treatment using detachable coils in a transarterial double-catheter technique. Case report and review of the literature.
J Neurosurg. 2004 Oct;101(4):697-9.Your thoughts are welcome.
Ilias Iladis, M.D.
Neurologist
(c) 2007 M. H. Rivner