Lumbar Elastance and Resistance to CSF Outflow Correlated to Patency of the Cranial Subarachnoid Space and Clinical Outcome of Endoscopic Third Ventriculostomy in Obstructive Hydrocephalus

Abstract

Object: The purpose of the present study was to elucidate the value of the lumbar and intraventricular infusion tests in the selection of patients with obstructive hydrocephalus (OH) for endoscopic third ventriculostomy (ETV), and whether the presence of a diminished cranial subarachnoid space was a source of error in the interpretation of the results.

Methods: In 32 consecutive adult patients (15 M, 17 F, mean age: 46 years) with possible treatment-requiring OH, the resistance to cerebrospinal fluid (CSF) outflow (R_out) and elastance was measured with a lumbar infusion test. Eleven of the patients underwent an additional intraventricular infusion test. An ETV was subsequently performed in 20 patients, of whom 11 presented with idiopathic aqueductal stenosis and 9 with other various causes of OH.

Results: The presence of a diminished cranial SAS correlated significantly with increased lumbar elastance, but not with lumbar R_out. However, distinctly increased R_out values (>24 mmHg/mL/min, n=4) were only measured in the presence of a diminished cranial SAS. No significant correlation was demonstrated between the clinical outcome of ETV and lumbar elastance or lumbar R_out, although seven out of the eight improving patients with aqueductal stenosis presented normal lumbar R_out values. In patients undergoing both a lumbar and an intraventricular infusion test and improving after ETV (n=6), lumbar elastance was significantly increased compared to the intraventricular elastance.

Conclusion: A diminished cranial SAS correlates with increased lumbar elastance and may explain the highly increased lumbar R_out values, possibly by impeding the bulk flow from the infusion. The majority of patients improving after ETV and presenting a normal sized cranial SAS presented normal lumbar R_out values. Supplementing the lumbar infusion test with an intraventricular test may help in predicting the outcome of ETV.

elastance - endoscopic third ventriculostomy - obstructive hydrocephalus - resistance to CSF outflow

References

• 1 Hopf NJ, Grunert P, Fries G, Resch KD, Perneczky A. Endoscopic third ventriculostomy: outcome analysis of 100 consecutive procedures.  Neurosurgery. 1999;  44 795-804
• 2 Abtin K, Thompson BG, Walker ML. Basilar artery perforation as a complication of endoscopic third ventriculostomy.  Pediatr Neurosurg. 1998;  28 35-41
• 3 Tisell M, Almstrom O, Stephensen H, Tullberg M, Wikkelsø C. How effective is endoscopic third ventriculostomy in treating adult hydrocephalus caused by primary aqueductal stenosis?.  Neurosurgery. 2000;  46 104-110
• 4 Boon AJ, Tans JT, Deiwel EJ, Egeler-Peerdeman SM, Hanlo PW, Wurzer HA, Avezaat CJ, Jong DA de, Goosk RH, Hermans J. Dutch normal-pressure hydrocephalus study: prediction of outcome after shunting by resistance to outflow of cerebrospinal fluid.  J Neurosurg. 1997;  87 687-693
• 5 Tisell M, Edsbagge M, Stephensen H, Czosnyka M, Wikkelsø C. Elastance correlates with outcome after endoscopic third ventriculostomy in adults with hydrocephalus caused by primary aqueductal stenosis.  Neurosurgery. 2002;  50 70-77
• 6 Czosnyka M, Whitehouse H, Smielewski P, Simac S, Pickard JD. Testing of cerebrospinal compensatory reserve in shunted and non-shunted patients: a guide to interpretation based on an observational study.  J Neurol Neurosurg Psychiatry. 1996;  60 549-558
• 7 Reisberg B, Ferris SH, Leon M de, Crook T. The global deterioration scale for assessment of primary degenerative dementia.  Am J Psychiatry. 1982;  139 1136-1139
• 8 Evans WA. An encephalographic ratio for estimating ventricular enlargement and cerebral atrophy.  Arch Neurol. 1974;  47 931-937
• 9 Gyldensted C. Measurements of the normal ventricular system and hemispheric sulci of 100 adults with computed tomography.  Neuroradiology. 1977;  14 183-192
• 10 Thomsen AM, Børgesen SE, Bruhn P, Gjerris F. Prognosis of dementia in normal-pressure hydrocephalus after a shunt operation.  Ann Neurol. 1986;  20 304-310
• 11 Børgesen SE, Gjerris F. The predictive value of conductance to outflow of CSF in normal pressure hydrocephalus.  Brain. 1982;  105 65-86
• 12 Bland JM, Altman DG. Multiple significance tests: the Bonferroni method.  BMJ. 1995;  310 170
• 13 Jones RF, Kwok BC, Stening WA, Vonau M. Neuroendoscopic third ventriculostomy. A practical alternative to extracranial shunts in non-communicating hydrocephalus.  Acta Neurochir Suppl (Wien). 1994;  61 79-83
• 14 Fukuhara T, Vorster SJ, Luciano MG. Risk factors for failure of endoscopic third ventriculostomy for obstructive hydrocephalus.  Neurosurgery. 2000;  46 1100-1109
• 15 Tisell M, Tullberg M, Helistrom P, Blomsterwall E, Wikkelsø C. Neurological symptoms and signs in adult aqueductal stenosis.  Acta Neurol Scand. 2003;  107 311-317
• 16 Nugent GR, Al Mefty O, Chou S. Communicating hydrocephalus as a cause of aqueductal stenosis.  J Neurosurg. 1979;  51 812-818
• 17 Williams B. Is aqueduct stenosis a result of hydrocephalus?.  Brain. 1973;  96 399-412
• 18 Foltz EL, Shurtleff DB. Conversion of communicating hydrocephalus to stenosis or occlusion of the aqueduct during ventricular shunt.  J Neurosurg. 1966;  24 520-529
• 19 Bech RA, Bøgeskov L, Børgesen SE, Juhler M. Indications for shunt insertion or III ventriculostomy in hydrocephalic children, guided by lumbar and intraventricular infusion tests.  Childs Nerv Syst. 1999;  15 213-217
• 20 Magnaes B. Cerebrospinal fluid hydromechanics in adult patients with benign noncommunicating hydrocephalus: one-hour test shunting and balanced cerebrospinal fluid infusion test to select patients for intracranial bypass operation.  Neurosurgery. 1982;  11 769-775
• 21 Magnaes B. Hydromechanical testing in non-communicating hydrocephalus to select patients for microsurgical third ventriculostomy.  Br J Neurosurg. 1989;  3 443-450
• 22 Grant JA, MacLone DG. Third ventriculostomy: a review.  Surg Neurol. 1997;  47 210-212
• 23 Frim DM, Goumnerova LC. Telemetric intraventricular pressure measurements after third ventriculocisternostomy in a patient with non-communicating hydrocephalus.  Neurosurgery. 1997;  41 1425-1428
• 24 Oi S, Rocco C Di. Proposal of “evolution theory in cerebrospinal fluid dynamics” and minor pathway hydrocephalus in developing immature brain.  Childs Nerv Syst. 2006;  22 662-669
• 25 Tans JT, Poortvliet DCJ. Comparison of lumbar and ventricular constant flow and bolus infusions in hydrocephalus. In: Avezaat CJ, Eijndhoven JHM, Mans AIR, Tans JT, eds. Intracranial pressure VIII. Berlin, Heidelberg: Springer-Verlag 1993: 749-752
• 26 Gangemi M, Maiuri F, Buonamassa S, Colella G, Divitiis E de. Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus.  Neurosurgery. 2004;  55 129-134
• 27 Meier U, Zeilinger FS, Schonherr B. Endoscopic ventriculostomy versus shunt operation in normal pressure hydrocephalus: diagnostics and indication.  Acta Neurochir Suppl (Wien). 2000;  43 87-90

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