Adult Normal Pressure Hydrocephalus Research Articles

428 The Lumbar Tap Trial Experience: An Analysis of Outcomes in 133 Adult Normal Pressure Hydrocephalus Patients Undergoing 2-Day Lumbar Tap Trial at a Single Center

INTRODUCTION: Lumbar Tap Trial (LTT) with high volume cerebrospinal fluid (CSF) removal is one of the primary adjunct testing modalities at a neurosurgeon’s disposal in the diagnosis of normal pressure hydrocephalus (NPH). Patients responsive to LTT may receive permanent fluid diversion by way of shunt placement. METHODS: Retrospective review of the electronic medical records of 133 patients that underwent a 2-day LTT by a single surgeon at our adult hydrocephalus center was conducted. Each patient has been closely followed at our hydrocephalus clinic from the time of symptomatic presentation through LTT, eventual shunt placement (if performed), and frequent post-operative assessments. Assessment of improvement during LTT and following shunt placement includes a timed 25 ft. walk test at our clinic. RESULTS: From 2016 – present, 133 patients have undergone 136 completed LTTs. During initial LTT, no major complications such as death, infection, hemorrhage, or nerve-root injury were seen. Minor complications included post-tap low back pain, headache, and transient nerve-root irritation. Average improvement during timed 25 ft. walk test was 6.6 sec following LTT. Average improvement in timed walk test in patients receiving shunt placement was 13.9 sec compared to post LTT walk time. CONCLUSION: In patients with suspected NPH, high-volume LTT was found to be an effective and safe diagnostic tool in our patient population. Patients demonstrating significant objective improvement during a timed walk test are frequently recommended for shunting. Patients undergoing shunt placement following improvement on LTT continued to improve with a mean decrease in walk time post-operatively, highlighting the effectiveness of LTT in predicting symptomatic response to shunt placement.

Reappraisal of Pediatric Normal-Pressure Hydrocephalus.

While normal-pressure hydrocephalus (NPH) is most commonly diagnosed in older adulthood, a significant body of literature has accumulated over half a century documenting the clinical phenomenon of an NPH-like syndrome in pediatric patients. As in adult NPH, it is likely that pediatric NPH occurs due to a heterogeneous array of developmental, structural, and neurodegenerative pathologies, ultimately resulting in aberrant cerebrospinal fluid (CSF) flow and distribution within and around the brain. In this review, we aimed to systematically survey the existing clinical evidence supporting the existence of a pediatric form of NPH, dating back to the original recognition of NPH as a clinically significant subtype of communicating hydrocephalus. Leveraging emergent trends from the old and more recent published literature, we then present a modern characterization of pediatric NPH as a disorder firmly within the same disease spectrum as adult NPH, likely with overlapping etiology and pathophysiological mechanisms. Exemplary cases consistent with the diagnosis of pediatric NPH selected from the senior author’s neurosurgical practice are then presented alongside the systematic review to aid in discussion of the typical clinical and radiographic manifestations of pediatric NPH. Common co-morbidities and modern surgical treatment options are also described.

Diffusional Kurtosis along the Corticospinal Tract in Adult Normal Pressure Hydrocephalus.

Normal Pressure Hydrocephalus is a reversible form of dementia characterized by enlarged ventricles, which can deform and cause disruptions to adjacent white matter fibers. The purpose of this work was to examine how diffusion and kurtosis parameters vary along the corticospinal tract and determine where along this path microstructure is compromised in patients diagnosed with normal pressure hydrocephalus. We hypothesized that disruption of the corticospinal tract from ventricular enlargement can be measured using diffusion MR imaging and this will be quantified in periventricular regions. We developed a method to analyze diffusion parameters at discrete points along neural tracts. We then used diffusion MR imaging data from patients with Alzheimer disease and healthy controls to compare whether diffusion along the corticospinal tract differs from that of patients with normal pressure hydrocephalus. We found that diffusion parameters can differentiate patients with normal pressure hydrocephalus from those with Alzheimer disease and healthy controls: Axial diffusion, axial kurtosis, and the axonal water fraction were found to differ significantly across groups (P < .05) in an area located close to the superior internal capsule and corona radiata but below the cortex. A lower axonal water fraction indicates a lower axonal density in the corticospinal tract, which may indicate permanent damage. Lower axial kurtosis may imply that axons are being more aligned due to compression.

Is There a Link Between ICP-Derived Infusion Test Parameters and Outcome After Shunting in Normal Pressure Hydrocephalus?

The term "hydrocephalus" encompasses a range of disorders characterised by clinical symptoms, abnormal brain imaging and derangement of cerebrospinal fluid (CSF) dynamics. The ability to elucidate which patients would benefit from CSF diversion (a shunt or third ventriculostomy) is often unclear. Similar difficulties are encountered in shunted patients to predict the scope for improvement by shunt re-adjustment or revision. We compared retrospective pre-shunting infusion test results performed in 310 adult patients diagnosed with normal pressure hydrocephalus (NPH) and their improvement after shunting. Resistance to CSF outflow correlated significantly with improvement (p < 0.05). Other markers known from the literature, such as amplitude in CSF pulse pressure, the slope of the amplitude-pressure regression line, or elasticity did not show any correlation with outcome. Outcome following shunting in adult NPH is associated with resistance to CSF outflow; however, the latter cannot be taken as an absolute predictor of shunt response.

Assessment of the urodynamic diagnosis in patients with urinary incontinence associated with normal pressure hydrocephalus.

To assess the urodynamic patterns present in patients with adult normal pressure hydrocephalus (NPH) in our institution. Retrospectively conducted study on patients diagnosed with NPH by the Neurosurgery Department of our institution, without etiological treatment or urogynecological disorders, who underwent an urodynamic study (UDS) performed according to methods proposed by the International Society of Continence (ICS). Clinical information, complementary tests and UDS were collected, and descriptive analysis was performed, with special focus in urodynamic final diagnosis. Eighty-one UDS performed between 2003 and 2013. Fifty-one Males (63%). Mean age: 74.89 ± 8.58 years old (range 52-88 years). Classical triad of symptoms: gait disturbance, dementia, and urinary incontinence (UI) presented in 48.1%. Urinary urgency in 80.9% and UI in 70%. In two cases (2.5%) UDS was not valuable. Urodynamic features of the 79 remaining studies revealed overactive detrusor (OD) in 56 patients (70.9%), being associated with Stress UI (SUI) in one case and with bladder outlet obstruction (BOO) in 19. SUI in six patients (7.6%) and BOO in five (6.3%). Detrusor underactivity in four cases (5%) and normal study in eight (10.1%). About 47.1% of males presented BOO. Cerebrospinal fluid shunt surgery was performed on 32 patients during follow-up, with subsequent clinical improvement in 90.6% of them. OD was the most frequent diagnosis within UDS conducted on adult NPH patients in our institution, with BOO in an elevated percentage of them. Etiological treatment led to symptomatic improvement in most of patients.

Adult onset familial normal pressure hydrocephalus? Neuropsychological profile of monozygotic twins

Background There are few cases of adult onset familial normal pressure hydrocephalus (NPH) reported in the literature but the rarity of the disease makes coincidence unlikely. Female monozygotic twins presenting with the NPH triad of symptoms were assessed on a neuropsychological test battery. The aims were to determine whether the neuropsychological evidence could support the differential diagnosis of adult onset NPH whilst contributing to a further understanding of the neuropsychological profile of adult NPH.

Clinical experience with a new pressure-adjustable shunt valve.

The pressure-adjustable valve system Codman Medos allows valve pressure adjustment in 18 steps between 30 and 200 mm H2O. A series of 90 patients, 15 children and 75 adults, who were shunted with this new programmable valve, is reported. Indication for shunt insertion were various types of hydrocephalus in 79 cases, malfunction of a medium pressure membrane valve shunt system in 9 cases and an arachnoid cyst and pseudotumour each in one case. The valve pressure was programmed prior to insertion to 200 mm H2O in the adults and according to age in children and was modified postoperatively according to the clinical course. Underdrainage with subdural fluid collections appearing in 5 patients could be managed by valve pressure adjustment alone in 2 cases. One malfunctioning of the valve mechanism was due to mechanical obstruction. At the time of follow-up, 7 to 29 months after operation, outcome was excellent in 64 patients, good with marked improvement but residual symptoms in 19 patients and unchanged in 7 patients. The possibility of adjusting the valve pressure to the patient's demands was frequently used in children and adult normal pressure hydrocephalus patients with satisfying clinical results.

Ultraviolet absorption substances in cerebrospinal fluid of normal pressure hydrocephalus

Optical densities (OD) were measured in ultraviolet absorption ranging from 210 to 310 nm in cerebrospinal fluid (CSF) samples obtained from 33 cases of adult normal pressure hydrocephalus. CSF samples from 100 patients, who had no neurological disorders served as control. All cases of adult normal pressure hydrocephalus were divided into three groups (excellent, good, non effective) according to the clinical improvement following the ventriculo-peritoneal (V-P) shunt operation. Two absorption peaks were ordinarily found in spectrophotometric analysis in CSF. The first peak at 230 nm was identified as the complex of albumin, γ-globulin and a few peptides through various biochemical analyses. The OD at 230 nm were significantly higher in both the excellent and good groups than in the normal control group (P<0.02, P<0.05) . For 24 hours prior to the shunt operation, continuous CSF drainage was made through lumbar route and the samples taken after 24 hours showed marked increases in the OD at 230 nm in the excellent and the good recovery groups. The second peak at 267 nm known as ascorbic acid absorption, remained significantly lower in all three groups than in the control group (P<0.001). Meglumine iothalamate (MI) was found in CSF as the maximum absorption at 245 nm following intravenous administration. Twenty-two samples taken 24 hours after intravenous administration of 100 ml of MI were studied. The OD at 245 nm were significantly higher in the excellent recovery group than the one in the non effective group (P<0.01). The increases in OD at 230 and 245 nm were thought to be due to the impairment of either the blood-brain or blood-CSF barrier and the development of edema in brain parenchyme. The cases who had high OD at 230 nm responded well to the V-P shunt operation. This was probably due to the removal of edema fluid through the hydrostatic pressure gradient between the brain and the ventricle. These results may be useful in deciding on surgical indication on patients of normal pressure hydrocephalus.