The Mechanism of Fornix Lesions in 3^rd Ventriculostomy

Abstract

Fornix lesions as a complication of 3^rd ventriculostomy are rare and almost not reported. However, in our series of 94 procedures we observed 5 fornix lesions. Although we did not find any clinical deterioration, we were alarmed by these unexpected incidences and analysed the mechanism. All fornix lesions occurred using an endoscope sheath with separated channels for the endoscope itself, the instruments and for rinsing and suction. The limited field of view suggests the surgeon to be already inside the 3^rd ventricle while the tip of the scope is still in the lateral ventricle just before the foramen of Monro. The instrument enters the optic field - depending on the used optic - as lately as 2 to 3 mm. The analysis showed that the lesions happened when the instruments were in the blind angle of the endoscope's optic which itself was outside of the foramen of Monro. Being aware of this mechanism with its potential risks it did not occurred again.

Key words

Third ventriculostomy - hydrocephalus - fornix - complications

References

• 1 Barlow P, Ching H S. An economic argument in favour of endoscopic third ventriculostomy as a treatment for obstructive hydrocephalus.  Minim Invas Neurosurg. 1997;  40 37-38
• 2 Cohen A R. Cranial endoscopy. Illustrative case.  Techniques in Neurosurg. 1995;  1 144-147
• 3 Drake J M. Ventriculostomy for treatment of hydrocephalus.  Neurosurg Clin North Am. 1993;  4 657-666
• 4 Hopf N J, Grunert P, Fries G, Resch K DM, Perneczky A. Endoscopic third ventriculostomy: outcome analysis of 100 consecutive procedures.  Neurosurg. 1999;  44 795-806
• 5 Jones R FC, Teo C, Stening W A, Kwok B CT. Neuroendoscopic third ventriculostomy. In: Manwaring KH, Crone KR (eds). Neuroendoscopy. New York: Mary Ann Liebert, Inc., Publishers 1992 1: 63-77
• 6 Kehler U, Gliemroth J, Wagner R, Arnold H. 3rd ventriculostomy versus ventriculoperitoneal shunt. An analysis of results, complications, and costs. Zentralbl Neurochir 1996 Suppl: 84 (abstract)
• 7 Kelly P J. Stereotactic third ventriculostomy in patients with nontumoral adolescent/ adult onset aqueductal stenosis and symptomatic hydrocephalus.  J Neurosurg. 1991;  75 865-873
• 8 Kunz U, Goldmann A, Bader C, Waldbaur H, Oldenkott P. Endoscopic fenestration of the 3^rd ventricular floor in aqueductal stenosis.  Minim Invasiv Neurosurg. 1994;  37 42-47
• 9 Oka K, Yamamoto M, Ikeda K, Tomonaga M. Flexible endoneurosurgical therapy for aqueductal stenosis.  Neurosurg. 1993;  33 236-242
• 10 Sainte-Rose C. Third ventriculostomy. In: Manwaring KH, Crone KR (eds.). Neuroendoscopy. New York: Mary Ann Liebert 1992 1: 47-62
• 11 Teo C. Third ventriculostomy in the treatment of hydrocephalus. Experience with more than 120 cases. In: Hellwig D, Bauer BL (eds.). Minimally Invasive Techniques for Neurosurgery. Berlin, Heidelberg, Berlin: Springer Verlag 1998: 73-76
• 12 Handler M H, Abbott R, Lee M. A near-fatal complication of endoscopic third ventriculostomy: case report.  Neurosurg. 1994;  35 525-527
• 13 Hirsch J F. Percutaneous ventriculocisternostomies in non-communicating hydrocephalus.  Monogr Neurol Sci. 1982;  8 170-178
• 14 Kehler U, Gliemroth J, Arnold H. Endoskopische Behandlung des Verschlusshydrocephalus.  Focus MUL. 1996;  13, Heft 2 82-87
• 15 McLaughlin M R, Wahlig J B, Kaufmann A M, Albright A L. Traumatic basilar aneurysm after endoscopic third ventriculostomy: case report.  Neurosurg. 1976;  41 1400-1403
• 16 Mohanty A, Anandh B, Reddy M S, Sastry K VR. Contralateral massive acute subdural collection after endoscopic third ventriculostomy - a case report.  Minim Invas Neurosurg. 1997;  40 59-61
• 17 Sayers M P, Kosnik E J. Percutaneous third ventriculostomy: Experience and technique.  Childs Brain. 1976;  2 24-30
• 18 Zamorano L, Chavantes C, Dujovny M, Malik G, Ausman J. Stereotatic endoscopic interventions in cystic and intraventricular brain lesions.  Acta Neurochir Suppl. 1992;  54 69-76
• 19 Hader W J, Drake J, Cochrane D, Sparrow O, Johnson E S, Kestle J. Death after late failure of third ventriculostomy in children. Report of three cases.  J Neurosurg. 2002;  97 211-215
• 20 Benabarre A, Ibánez J, Boget T, Obiols J, Martinéz-Aran A, Vieta E. Neuropsychological and psychiatric complications in endoscopic third ventriculostomy: a clinical case report.  J Neurol Neurosurg Psychiatry. 2001;  71 268-271
• 21 Schröder H W, Niendorf W R, Gaab M R. Complications of endoscopic third ventriculostomy.  J Neurosurg. 2002;  96 1032-1040