We provide microvascular decompression for trigeminal neuralgia in some rare conditions. 1. Trigeminal neuralgia caused by larger arteries, such as vertebral or basilar artery. Some additional technique is required to treat with this condition, as transposition of the culprit artery is sometimes difficult. The nerve is vend by the vertebral artery The nerve recovered to be straight after decompression. 2. Trigeminal neuralgia caused by vein. As for this condition, it is generally difficult to get precise diagnosis by non-contrast MRI. Contrast enhanced MRI must be necessary to make a precise diagnosis. As this type of trigeminal neuralgia carries higher risk of recurrence, cutting the vein is preferable rather than transposition of the veins. 3D image Intraoperative View Artery (red) has no contact with the trigeminal nerve (yellow), while only vein (blue) has contact on the nerve. The vein (arrow head) contact with the trigeminal nerve (arrow). The insertion is the pre-OP 3D image, represents the same picture with the real operative findings. 3. Trigeminal neuralgia caused by arachnoid adhesion. This type of trigeminal neuralgia is difficult to diagnose only by MRI. Careful history taking is only the way to establish the diagnosis. In this case, cutting the arachnoid membrane attaching on the nerve relieved the pain. 4.Trigeminal Neuralgia: Persistent primitive trigeminal artery (PTA) A primitive trigeminal artery (PTA) is a rare anomalous artery that originates from the internal carotid artery. A variant type of PTA runs close to the trigeminal nerve and may cause trigeminal neuralgia. The trigeminal nerve is compressed by the PTA at the REZ. PTA penetrates the dura matter just beneath the trigeminal nerve. 5.Trigeminal Neuralgia: Trigeminocerebellar artery (TCA) The trigeminocerebellar artery (TCA) is rarely found compressing the trigeminal nerve. Transposition of the TCA requires a different transposition technique as it penetrates or winds around the trigeminal nerve. The artery in pink is winding around the trigeminal nerve. 7. Trigeminal neuralgia caused by tumors. 5〜10% among trigeminal neuralgia may be caused by brain tumors, such as meningioma, shwannoma and epidermoid. The symptom will be cured by removing the tumors around the nerve. Appropriate removal may differ in case by case. Fig.1　Trigeminal neuralgia caused by small Meningioma Fig.2　Trigeminal neuralgia caused by Epidermoid Gamma Knife is applied to control the pain. Partial removal around the trigeminal nerve lead pain free. Fig.3　Trigeminal neuralgia caused by large Meningioma Pre Op After Op Tumor was totally removed, the patient got pain free. Trigeminal neuralgia due to Epidermoid Pain free after tumor removal. Shwannoma compressing the trigeminal nerve Pain free after releasing the compression. Lipoma surrounding the trigeminal nerve Pain free after partial removal of the contact on the nerve. Meningioma compressing the trigeminal nerve Pain free after removal of the tumor. 5. Recurrence Inadequate surgery might cause recurrence of the symptom. Foreign materials inserted between the nerve and artery highly causes the recurrence of trigeminal neuralgia. Removal of the material is required to treat this condition, which usually meticulous dissection from the nerve is required. Former inserted Teflon adhesion between the nerve and artery was the cause of Trigeminal neuralgia. Too much Ivaron caused the Trigeminal neuralgia. The symptom subsided after removal. 8. Trigeminal neuralgia caused by anomaly or malformations. Anomaly of the cranium, venous angioma and persistent trigeminal artery may cause trigeminal neuralgia. Precise diagnosis and adequate strategy is important for curative surgery. 【8-1 Trigeminal neuralgia due to venous angioma】 Venous angioma around the trigeminal nerve Magnified view from operative side   Translucent view of the vein reveals the contact of the arteries on the nerve. Two arteries and two veins are found to have contact with the nerve on the both side. Decompression before After decompression The nerve is pinched by two large veins. Two pair of arteries and veins were culprit in this case. Trigeminal neuralgia caused by Varix. A, B: Varix (white arrow) compressing the trigeminal nerve (*) C, D: Transposition of the Varix relieved the pain. 【8-2 Trigeminal neuralgia due to Anomaly of the cranium】 Trigeminal neuralgia due to Anomaly of the cranium   　 Normal approach behind the ear is difficult to operate in this case. 　 Approach through temporal side enabled to release the compression of the bone. 【8-3 Trigeminal neuralgia caused by Persistent trigeminal artery】 Trigeminal neuralgia caused by Persistent trigeminal artery Multiple arteries were responsible in this case. Takuro INOUE M.D., Ph.D. Chief Director, Neurosurgery, Kotoh Memorial Hospital 2015 Chief Director, visiting consultant Andalusia Hospital, Egypt 2010 to present Chief Director, Kotoh Memorial Hospital, Shiga, Japan 2007 Clinical training at Duke University, USA 2004 Gamma Knife training at Kalorinska University, Sweden 1998-2009 Neurosurgery, Hino Memorial Hospital, Shiga, Japan 1997-1998 University of British Columbia, Canada 1994-1996 Neurosurgery, Okamoto General Hospital, Kyoto, Japan 1992-1993 Neurosurgery, Saiseikai Noe Hospital, Osaka, Japan 1991-1992 Neurosurgery, University of Shiga Medical Science Hospital 2013 Skull Base Workshop, Chulalongkorn University, Thailand 2013 Asean Cerebrovascular Skull Base Hand On Course & Symposium, Chulalongkorn University, Thailand 2011 Advanced Skull Base Microanatomy Workshop and Hands-On Dissection Course, Florida, USA 2010 Advanced Skull Base Microanatomy Workshop and Hands-On Dissection Course, Florida, USA 2008 Cadaver Workshop on Skull Base, Aichi, Japan 2008 Cadaver Dissection Course, Kyoto, Japan For your reservation, E-mail subaru@gammaknife-c.jp or leave message here ▲UP ■Site Map Copyright (C) 2006 The Neurosurgery Center. 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