Determination of cerebrospinal fluid shunt obstruction with magnetic resonance phase imaging

1991 ◽  
Vol 75 (4) ◽  
pp. 535-540 ◽  
Author(s):  
James M. Drake ◽  
Alastair J. Martin ◽  
R. Mark Henkleman
Keyword(s):  
Cerebrospinal Fluid ◽  
Magnetic Resonance ◽  
Pulse Sequence ◽  
Csf Shunt ◽  
Phase Imaging ◽  
Flow Rates ◽  
Content Type ◽  
Patients Âgés ◽  
Shunt Obstruction

✓ The cerebrospinal fluid (CSF) flow rates in 12 patients with symptoms suggestive of CSF shunt obstruction were measured with magnetic resonance (MR) phase imaging. The shunts were imaged over the skull, just distal to any reservoir, using a curved surface coil. Images perpendicular to the direction of flow were made on a 1.5-tesla clinical unit with a flow-sensitive pulse sequence. The patients' ages ranged from 2 months to 28 years. All patients had ancillary investigations to determine the functional status of the shunt. No flow was detected in seven patients with blocked shunts. Flow rates between 3 and 40 cc/hr were found in three patients with functioning shunts. Two patients, one with a blocked shunt and one with a functioning shunt, could not be imaged due to motion artifact. Magnetic resonance phase imaging is a promising technique in the determination of CSF shunt obstruction.

Cerebrospinal fluid edema associated with shunt obstruction

1994 ◽  
Vol 81 (2) ◽  
pp. 179-183 ◽  
Author(s):  
Hiroaki Sakamoto ◽  
Ken Fujitani ◽  
Shouhei Kitano ◽  
Keiji Murata ◽  
Akira Hakuba
Keyword(s):  
Cerebrospinal Fluid ◽  
Subcortical White Matter ◽  
Shunt Revision ◽  
Csf Shunt ◽  
Limited Area ◽  
Ventricular Catheter ◽  
Small Lesion ◽  
Rapid Improvement ◽  
Content Type ◽  
Shunt Obstruction

✓ The authors report four hydrocephalic children with cerebrospinal fluid (CSF) edema extending along the ventricular catheter of an obstructed CSF shunt. Three of the patients exhibited massive CSF edema along the ventricular catheter, yet they manifested neither ventricular enlargement nor apparent periventricular CSF edema despite increased intraventricular pressure. These findings suggested ventricular tautness. The remaining patient, who had dilated ventricles with periventricular CSF edema, displayed CSF edema in a limited area along the ventricular catheter. Replacement of the obstructed peritoneal catheter of the shunt resulted in rapid improvement of the edema in all patients. In the three patients with massive CSF edema, however, a small lesion remained in the subcortical white matter along the ventricular catheter as demonstrated by computerized tomography and/or magnetic resonance imaging 3 to 5 years after shunt revision. It is concluded that shunt obstruction may result in massive CSF edema along the ventricular catheter in hydrocephalic children who have ventricular tautness after installation of the shunt causing irreversible although usually asymptomatic damage to the affected area of the brain.

Cerebrospinal fluid shunts: an experimental comparison of flow rates and pressure values in various commercial systems

1972 ◽  
Vol 37 (6) ◽  
pp. 700-705 ◽  
Author(s):  
John L. Fox ◽  
David C. McCullough ◽  
Robert C. Green
Keyword(s):  
Cerebrospinal Fluid ◽  
Hydrostatic Pressure ◽  
Flow Rate ◽  
Experimental Comparison ◽  
Csf Shunt ◽  
Opening Pressure ◽  
Flow Rates ◽  
Content Type ◽  
Actual Flow ◽  
Closing Pressure

✓ The flow-rate characteristics of selected cerebrospinal fluid (CSF) shunt systems under a constant hydrostatic pressure differential were studied and compared with measurements of the opening pressure (OP) and closing pressure (CP). The usual technique of measuring the CP correlated poorly with actual flow rates. The OP measurement revealed variations from 5 to 600 mm H2O in the hydrostatic pressure actually needed to open the valve. The flow-rate values are important in that some shunt systems will not deliver distilled water at rates significantly in excess of 0.35 ml/min (the probable average normal CSF production rate) at hydrostatic pressure differentials of 150 mm H2O. However, this may not be apparent clinically since much higher hydrostatic pressure differentials are present in the erect patient with a CSF shunt where the ventricular pressure and shunt siphoning pressures are additive.

Thermosensitive determination of CSF shunt patency with a pair of small disc thermistors

1980 ◽  
Vol 52 (5) ◽  
pp. 700-704 ◽  
Author(s):  
Yasuhiro Chiba ◽  
Kenji Yuda
Keyword(s):  
Normal Pressure ◽  
Adult Patients ◽  
Csf Shunt ◽  
Simple Method ◽  
Content Type ◽  
Temperature Changes ◽  
Small Disc ◽  
Clinical Pictures ◽  
Shunt Obstruction

✓ A simple method is presented for detecting the patency of ventriculoperitoneal shunts with a pair of small disc thermistors. In an experimental model, the equipment detected definite temperature changes along the shunt tube. The extent of the temperature difference was proportional to the flow velocities, ranging from 5 to 60 ml/hr (120 to 1440 ml/24 hrs). A clinical study consisted of 26 trials in 23 hydrocephalic children and 10 trials in nine adult patients with normal-pressure hydrocephalus. Three of the 26 trials in the children were unsuccessful because of patient irritability and lack of cooperation. All trials for adult patients were successful. In all 25 patients, whose clinical pictures suggested functioning shunt, accurate confirmation of shunt patency was obtained. In six patients whose clinical pictures suggested questionable shunt function, this method revealed that all shunts were patent, and computerized tomography and follow-up clinical data supported this finding. In two patients whose clinical pictures suggested shunt malfunction, there was no indicator deflection, and shunt obstruction was proved at operation. This method is effective in checking shunt function, is simple, and may be repeated at frequent intervals.

Analysis of aqueductal cerebrospinal fluid flow after endoscopic aqueductoplasty by using cine phase-contrast magnetic resonance imaging

2000 ◽  
Vol 93 (2) ◽  
pp. 237-244 ◽  
Author(s):  
Henry W. S. Schroeder ◽  
Christiane Schweim ◽  
Klaus H. Schweim ◽  
Michael R. Gaab
Keyword(s):  
Cerebrospinal Fluid ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Healthy Volunteers ◽  
Phase Contrast ◽  
Aqueductal Stenosis ◽  
Csf Flow ◽  
Content Type ◽  
Endoscopic Aqueductoplasty ◽  
Fine Print

Object. The purpose of this prospective study was to evaluate aqueductal cerebrospinal fluid (CSF) flow after endoscopic aqueductoplasty. In all patients, preoperative magnetic resonance (MR) imaging revealed hydrocephalus caused by aqueductal stenosis and lack of aqueductal CSF flow.Methods. In 14 healthy volunteers and in eight patients with aqueductal stenosis who had undergone endoscopic aqueductoplasty, aqueductal CSF flow was investigated using cine cardiac-gated phase-contrast MR imaging. For qualitative evaluation of CSF flow, the authors used an in-plane phase-contrast sequence in the midsagittal plane. The MR images were displayed in a closed-loop cine format. Quantitative through-plane measurements were performed in the axial plane perpendicular to the aqueduct. Evaluation revealed no significant difference in aqueductal CSF flow between healthy volunteers and patients with regard to temporal parameters, CSF peak and mean velocities, mean flow, and stroke volume. All restored aqueducts have remained patent 7 to 31 months after surgery.Conclusions. Aqueductal CSF flow after endoscopic aqueductoplasty is similar to aqueductal CSF flow in healthy volunteers. The data indicate that endoscopic aqueductoplasty seems to restore physiological aqueductal CSF flow.

Management of proximal shunt obstruction

1988 ◽  
Vol 68 (5) ◽  
pp. 817-819 ◽  
Author(s):  
Charles C. Duncan
Keyword(s):  
Cerebrospinal Fluid ◽  
Fluid Flow ◽  
Intracranial Pressure ◽  
Signs And Symptoms ◽  
Ventricular Catheter ◽  
Shunt Failure ◽  
Content Type ◽  
Cerebrospinal Fluid Flow ◽  
Shunt Obstruction ◽  
Fine Print

✓ Proximal shunt obstruction or obstruction of the ventricular catheter may present with signs and symptoms of shunt failure with either no cerebrospinal fluid flow or a falsely low intracranial pressure (ICP) upon shunt tap. The author reports a technique for lowering the ICP and for measuring the pressure in patients with such obstruction by cannulation of the reservoir and ventricular catheter to penetrate into the ventricle with a 3½-in. No. 22 spinal needle. The findings in 20 cases in which this approach was utilized are summarized.

Stretching and breaking characteristics of cerebrospinal fluid shunt tubing

2003 ◽  
Vol 98 (3) ◽  
pp. 578-583 ◽  
Author(s):  
Daniel J. Tomes ◽  
Leslie C. Hellbusch ◽  
L. Russell Alberts
Keyword(s):  
Cerebrospinal Fluid ◽  
Applied Stress ◽  
Revision Surgery ◽  
Csf Shunt ◽  
Stress And Strain ◽  
Sectional Area ◽  
Cross Sectional ◽  
Content Type ◽  
Shunt Tubing ◽  
Fine Print

Object. Cerebrospinal fluid (CSF) shunt system malfunction due to silastic tubing fracture necessitates revision surgery in shunt-dependent individuals. The goal of this study was to examine the mechanical stretching and breaking characteristics of new and used CSF shunt tubing catheters to determine if any inherent physical properties predispose the tubing to fracture. Methods. Fifty-millimeter segments of new and retrieved (used) CSF shunt tubing were stretched to 120 mm in a hydraulic press to determine modulus values (modulus = stress/strain) and to measure permanent tubing deformation imparted by the applied stress and strain. Similar 50-mm tubing segments were also stretched in an electromechanical material testing system until fracture occurred; the force and strain needed to break the tubing was recorded at the time of failure. The results demonstrate that shunt tubing with a greater cross-sectional area requires greater force to fracture, and that catheters become weaker the longer they are implanted. Barium-impregnated shunt tubing, compared with translucent tubing, appears to require less applied stress and strain to break and may fracture more easily in vivo. The variety of modulus values obtained for the new catheters tested indicates that the various companies may be using materials of different quality in tubing manufacture. Conclusions. A CSF shunt catheter design that incorporates tubing with a greater cross-sectional area may lead to fewer fractures of indwelling catheters and a reduction in shunt revision surgery.

Cerebrospinal fluid shunt placement for pseudotumor cerebri—associated intractable headache: predictors of treatment response and an analysis of long-term outcomes

2004 ◽  
Vol 101 (4) ◽  
pp. 627-632 ◽  
Author(s):  
Matthew J. Mcgirt ◽  
Graeme Woodworth ◽  
George Thomas ◽  
Neil Miller ◽  
Michael Williams ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Pseudotumor Cerebri ◽  
Shunt Revision ◽  
Csf Shunts ◽  
Content Type ◽  
Shunt Placement ◽  
Increased Risk ◽  
Shunt Obstruction ◽  
Fine Print

Object. Cerebrospinal fluid (CSF) shunts effectively reverse symptoms of pseudotumor cerebri postoperatively, but long-term outcome has not been investigated. Lumboperitoneal (LP) shunts are the mainstay of CSF shunts for pseudotumor cerebri; however, image-guided stereotaxy and neuroendoscopy now allow effective placement of a ventricular catheter without causing ventriculomegaly in these cases. To date it remains unknown if CSF shunts provide long-term relief from pseudotumor cerebri and whether a ventricular shunt is better than an LP shunt. The authors investigated these possibilities. Methods. The authors reviewed the records of all shunt placement procedures that were performed for intractable headache due to pseudotumor cerebri at one institution between 1973 and 2003. Using proportional hazards regression analysis, predictors of treatment failure (continued headache despite a properly functioning shunt) were assessed, and shunt revision and complication rates were compared between LP and ventricular (ventriculoperitoneal [VP] or ventriculoatrial [VAT]) shunts. Forty-two patients underwent 115 shunt placement procedures: 79 in which an LP shunt was used and 36 in which a VP or VAT shunt was used. Forty patients (95%) experienced a significant improvement in their headaches immediately after the shunt was inserted. Severe headache recurred despite a properly functioning shunt in eight (19%) and 20 (48%) patients by 12 and 36 months, respectively, after the initial shunt placement surgery. Seventeen patients without papilledema and 19 patients in whom preoperative symptoms had occurred for longer than 2 years experienced recurrent headache, making patients with papilledema or long-term symptoms fivefold (relative risk [RR] 5.2, 95% confidence interval [CI] 1.5–17.8; p < 0.01) or 2.5-fold (RR 2.51, 95% CI 1.01–9.39; p = 0.05) more likely to experience headache recurrence, respectively. In contrast to VP or VAT shunts, LP shunts were associated with a 2.5-fold increased risk of shunt revision (RR 2.5, 95% CI 1.5–4.3; p < 0.001) due to a threefold increased risk of shunt obstruction (RR 3, 95% CI 1.5–5.7; p < 0.005), but there were similar risks between the two types of shunts for overdrainage (RR 2.3, 95% CI 0.8–7.9; p = 0.22), distal catheter migration (RR 2.1, 95% CI 0.3–19.3; p = 0.55), and shunt infection (RR 1.3, 95% CI 0.3–13.2; p = 0.75). Conclusions. Based on their 30-year experience in the treatment of these patients, the authors found that CSF shunts were extremely effective in the acute treatment of pseudotumor cerebri—associated intractable headache, providing long-term relief in the majority of patients. Lack of papilledema and long-standing symptoms were risk factors for treatment failure. The use of ventricular shunts for pseudotumor cerebri was associated with a lower risk of shunt obstruction and revision than the use of LP shunts. Using ventricular shunts in patients with papilledema or symptoms lasting less than 2 years should be considered for those with pseudotumor cerebri—associated intractable headache.

Determination of cerebrospinal fluid shunt function with water-soluble contrast medium

1978 ◽  
Vol 49 (3) ◽  
pp. 398-407 ◽  
Author(s):  
Mario Savoiardo ◽  
Carlo L. Solero ◽  
Angelo Passerini ◽  
Franco Migliavacca
Keyword(s):  
Cerebrospinal Fluid ◽  
Contrast Medium ◽  
Water Soluble ◽  
Ventricular Catheter ◽  
Cerebrospinal Fluid Shunt ◽  
Distal Catheter ◽  
Content Type ◽  
Water Soluble Contrast ◽  
Water Soluble Contrast Medium

✓ Determination of cerebrospinal fluid shunt patency with water-soluble contrast medium is a simple, rapid, reliable, and safe technique. Since September, 1974, the authors performed 113 examinations. With the Spitz-Holter valve, only the atrial catheter can be studied, but, with the Pudenz valve and with the shunting devices that have a double-dome reservoir, both the proximal and the distal catheter can be visualized. Through the ventricular catheter a full ventriculographic study can be made, demonstrating ventricular size, malposition of the catheter, and the lesion that caused the hydrocephalus, or its evolution. The problem of collapsed ventricles, in which clinical and “manual” evaluation of the flushing device can give misleading findings, is emphasized. The injection of the atrial or peritoneal catheter in the pathological cases demonstrated its blockage, level of disconnection, malposition, sleeve, or cyst formation. Computerized tomography has only slightly decreased the number of these studies: when the ventricles are large, the examination with water-soluble contrast medium is still needed to demonstrate the exact level of malfunction. This demonstration has decreased the number of the total revisions or complete changes of shunting systems, eliminating some unnecessary changes of normally functioning catheters.

Hydrocephalus due to villous hypertrophy of the choroid plexus in the lateral ventricles

1994 ◽  
Vol 80 (2) ◽  
pp. 321-323 ◽  
Author(s):  
Hirofumi Hirano ◽  
Kazuho Hirahara ◽  
Tetsuhiko Asakura ◽  
Tetsuro Shimozuru ◽  
Koki Kadota ◽  
...  
Keyword(s):  
Cerebrospinal Fluid ◽  
Mental Retardation ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Choroid Plexus ◽  
Ventriculoperitoneal Shunt ◽  
Rare Case ◽  
Content Type ◽  
Lateral Ventricles ◽  
Fine Print

✓ A case is reported of hydrocephalus due to overproduction of cerebrospinal fluid (CSF) caused by villous hypertrophy of the choroid plexus in the lateral ventricles. A 7-year-old girl with mental retardation developed gait disturbance; hydrocephalus and a Dandy-Walker cyst were detected on computerized tomography. She was initially treated with a ventriculoperitoneal shunt; however, shunting failed to control the hydrocephalus. The excessive outflow of CSF suggested choroid plexus abnormality, and magnetic resonance (MR) imaging revealed enlargement of the choroid plexus in both lateral ventricles. The patient was therefore diagnosed as having hydrocephalus induced by overproduction of CSF, which was controlled by resection of the choroid plexus. Histological examination showed the structure typical of normal choroid plexus. This is a rare case of villous hypertrophy of the choroid plexus in which MR imaging assisted in the diagnosis.

scholarly journals Quantitative Analysis of Flavonoids in Glycyrrhiza uralensis Fisch by 1H-qNMR

2021 ◽  
Vol 2021 ◽  
pp. 1-6
Author(s):  
Ping Yu ◽  
Qian Li ◽  
Yanmei Feng ◽  
Yuying Chen ◽  
Sinan Ma ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Pulse Sequence ◽  
Quantitative Characteristic ◽  
Internal Standard ◽  
Proton Nuclear Magnetic Resonance ◽  
Experimental Result ◽  
Resonance Spectroscopy ◽  
Nuclear Magnetic

Objective. To establish a method for simultaneous determination of liquiritin, liquiritigenin, and isoliquiritinin glycyrrhizin using hydrogen nuclear magnetic resonance quantitative technology (1H-qNMR). Methodology. Deuterated dimethyl sulfoxide was used as the solvent, and dichloromethane was used as the internal standard. The probe temperature was 298.0 K, the pulse sequence was Zg30, the number of scans was 16, and relaxation delay (D1) was 10 s. Quantitative characteristic signal peaks were δ 4.891∼4.878 ppm, δ 8.187∼8.172 ppm, and δ 6.790∼6.776 ppm for liquiritin, isoliquiritin, and liquiritigenin, respectively. Results. The experimental result showed that the content of flavonoids in Licorice, from Chifeng, Inner Mongolia, was the highest. Conclusion. In this study, a new method for determination of three flavonoids in Licorice using 1H-qNMR was established. This experimental method has the advantages of accuracy, efficiency, and economy. It lays a foundation for the study on the determination of flavonoids content in licorice by proton nuclear magnetic resonance spectroscopy.

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