Sandra Fernandes Dias1,2, Afroditi-Despina Lalou3, Regine Spang1, Karin Haas-Lude4, Matthew Garnett3, Helen Fernandez3, Marek Czosnyka3,5, Martin U Schuhmann6, Zofia Czosnyka3. 1. Division of Pediatric Neurosurgery, Department of Neurosurgery, University Hospital of Tübingen, 72076, Tübingen, Germany. 2. Department of Neurosurgery, University Hospital of Zurich, 8091, Zürich, Switzerland. 3. Academic Neurosurgery Unit, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK. 4. Department of Pediatric Neurology, University Children's Hospital Tübingen, 72076, Tübingen, Germany. 5. Institute of Electronic Systems, Warsaw University of Technology, 00-661, Warsaw, Poland. 6. Division of Pediatric Neurosurgery, Department of Neurosurgery, University Hospital of Tübingen, 72076, Tübingen, Germany. martin.schuhmann@med.uni-tuebingen.de.
Abstract
BACKGROUND: Hydrocephalus shunt malfunction can-also in children-occur insidiously without clear symptoms of raised intracranial pressure (ICP) or changes in ventricular size, imposing a diagnostic challenge. Computerized shunt infusion studies enable quantitative shunt function assessment. We report on feasibility and results of this technique in children in a two center cross-sectional study. MATERIAL AND METHODS: Shunt infusion study (SIS) is performed with two needles inserted into a pre-chamber for ICP recording and CSF infusion. After baseline ICP recording, constant rate infusion is started until a new ICP plateau (ICPpl) is reached. Dedicated software containing the shunt's resistance characteristics calculates ICP and its amplitude outflow resistance and critical shunt pressure (CSP). Overall, 203 SIS were performed in 166 children. Shunts were defined as functional if ICPpl was <CSP and obstructed if ICPpl was > 5 mmHg above CSP and borderline in between. RESULTS: Forty-one shunts (20.2%) were found obstructed, 26 (12.8%) had borderline characteristics, and 136 (67%) were functional. Baseline ICP in obstructed shunts was significantly above shunt operating pressure. CSF outflow resistance (Rout) and ∆ICP plateau were significantly elevated in obstructed shunts, with cut-off thresholds of 8.07 mmHg min/ml and 11.74 mmHg respectively. Subgroup analysis showed smaller ventricles in 69% of revised cases. CONCLUSION: SIS is a feasible, reliable, and radiation-free technique for quantitative shunt assessment to rule out or prove shunt malfunction. Dedicated software containing shunt hydrodynamic characteristics is necessary and small children may need short-term sedation. Due to the clinical and inherent economic advantages, SIS should be more frequently used in pediatric neurosurgery.
BACKGROUND:Hydrocephalus shunt malfunction can-also in children-occur insidiously without clear symptoms of raised intracranial pressure (ICP) or changes in ventricular size, imposing a diagnostic challenge. Computerized shunt infusion studies enable quantitative shunt function assessment. We report on feasibility and results of this technique in children in a two center cross-sectional study. MATERIAL AND METHODS: Shunt infusion study (SIS) is performed with two needles inserted into a pre-chamber for ICP recording and CSF infusion. After baseline ICP recording, constant rate infusion is started until a new ICP plateau (ICPpl) is reached. Dedicated software containing the shunt's resistance characteristics calculates ICP and its amplitude outflow resistance and critical shunt pressure (CSP). Overall, 203 SIS were performed in 166 children. Shunts were defined as functional if ICPpl was <CSP and obstructed if ICPpl was > 5 mmHg above CSP and borderline in between. RESULTS: Forty-one shunts (20.2%) were found obstructed, 26 (12.8%) had borderline characteristics, and 136 (67%) were functional. Baseline ICP in obstructed shunts was significantly above shunt operating pressure. CSF outflow resistance (Rout) and ∆ICP plateau were significantly elevated in obstructed shunts, with cut-off thresholds of 8.07 mmHg min/ml and 11.74 mmHg respectively. Subgroup analysis showed smaller ventricles in 69% of revised cases. CONCLUSION: SIS is a feasible, reliable, and radiation-free technique for quantitative shunt assessment to rule out or prove shunt malfunction. Dedicated software containing shunt hydrodynamic characteristics is necessary and small children may need short-term sedation. Due to the clinical and inherent economic advantages, SIS should be more frequently used in pediatric neurosurgery.
Authors: Joseph R Madsen; Gani S Abazi; Laurel Fleming; Mark Proctor; Ron Grondin; Suresh Magge; Peter Casey; Tomer Anor Journal: Neurosurgery Date: 2011-01 Impact factor: 4.654
Authors: Esther B Dupepe; Betsy Hopson; James M Johnston; Curtis J Rozzelle; W Jerry Oakes; Jeffrey P Blount; Brandon G Rocque Journal: Neurosurg Focus Date: 2016-11 Impact factor: 4.047
Authors: Afroditi-Despina Lalou; Marek Czosnyka; Matthew R Garnett; Eva Nabbanja; Gianpaolo Petrella; Peter J Hutchinson; John D Pickard; Zofia Czosnyka Journal: Acta Neurochir (Wien) Date: 2020-02-20 Impact factor: 2.216