EVALUATION AND TREATMENT OF PATIENTS WITH SUSPECTED NORMAL PRESSURE HYDROCEPHALUS ON LONG-TERM WARFARIN ANTICOAGULATION THERAPY

Optimizing shunt integrity during acute subdural hematoma evacuation

Background

Even mild head trauma can cause severe intracranial hemorrhage in patients with cerebrospinal fluid (CSF) shunts for hydrocephalus. CSF shunts are considered a risk factor for subdural hematoma (SDH). The management of acute SDH (ASDH) in shunted patients with normal pressure hydrocephalus can be challenging. Addressing the hematoma and the draining function of the shunt is important. To preserve the shunt, we set the shunt valve pressure to the highest and perform hematoma evacuation for ASDH. In this study, we report the surgical cases of ASDH in patients with shunts.

Methods

Between 2013 and 2019, five patients with ASDH and CSF shunts underwent hematoma evacuation at our hospital. We retrospectively analyzed data regarding their clinical and radiological presentation, hospitalization course, the use of antithrombotic medications, and response to different treatment regimens.

Results

The patients presented with scores of 5-14 in the Glasgow coma scale and severe neurological signs, consciousness disturbance, and hemiparesis. Most patients were elderly, taking antithrombotic medications (four of five cases), and had experienced falls (4 of 5 cases). All patients underwent hematoma evacuation following resetting their programmable shunt valves to their maximal pressure setting and shunt preservation. ASDH enlargement was observed in only one patient who underwent burr-hole drainage. Glasgow outcome scale scores at discharge were 1 and 3, respectively.

Conclusion

In hematoma evacuation, increasing the valve pressure may reduce the bleeding recurrence. To preserve the shunt, setting the shunt valve pressure to the highest level and performing endoscopic hematoma evacuation with a small craniotomy could be useful.

Ventriculoperitoneal Shunt Placement Safety in Idiopathic Normal Pressure Hydrocephalus: Anticoagulated Versus Non-Anticoagulated Patients

BACKGROUND

Many patients with idiopathic normal pressure hydrocephalus (iNPH) have medical comorbidities requiring anticoagulation that could negatively impact outcomes. This study evaluated the safety of ventriculoperitoneal shunt placement in iNPH patients on systemic anticoagulation versus those not on anticoagulation.

METHODS

Patients >60 years of age with iNPH who underwent shunting between 2018 and 2022 were retrospectively reviewed. Baseline demographics, comorbidities (quantified by modified frailty index and Charlson comorbidity index), anticoagulant/antiplatelet agent use (other than aspirin), operative details, and complications were collected. Outcomes of interest were the occurrence of postoperative hemorrhage and overdrainage.

RESULTS

A total of 234 patients were included in the study (mean age 75.22 ± 6.04 years; 66.7% male); 36 were on anticoagulation/antiplatelet therapy (excluding aspirin). This included 6 on Warfarin, 19 on direct Xa inhibitors, 10 on Clopidogrel, and 1 on both Clopidogrel and Warfarin. Notably, 70% of patients (164/234) used aspirin alone or combined with anticoagulation or clopidogrel. Baseline modified frailty index was similar between groups, but those on anticoagulant/antiplatelet therapy had a higher mean Charlson comorbidity index (2.67 ± 1.87 vs. 1.75 ± 1.84; P = 0.001). Patients on anticoagulants were more likely to experience tract hemorrhage (11.1 vs. 2.5%; P = 0.03), with no significant difference in the rates of intraventricular hemorrhage or overdrainage-related subdural fluid collection.

CONCLUSIONS

Anticoagulant and antiplatelet agents are common in the iNPH population, and patients on these agents experienced higher rates of tract hemorrhage following ventriculoperitoneal shunt placement; however, overall hemorrhagic complication rates were similar.

Current Update on Treatment Strategies for Idiopathic Normal Pressure Hydrocephalus

PURPOSE OF REVIEW

Idiopathic normal pressure hydrocephalus (iNPH) is a surgically treatable neurological disorder of the elderly population that is characterized by abnormal ventricular enlargement due to cerebrospinal fluid (CSF) accumulation and gait disturbance, cognitive impairment, or urinary incontinence. The objective of this review is to present the current diagnostic and treatment approaches for iNPH and to discuss some of the postoperative modalities that complement positive surgical outcomes.

RECENT FINDINGS

Although historically reported patient outcomes following iNPH surgery were dismal and highly variable, recent advances in terms of better understanding of the iNPH disease process, better standardization of iNPH diagnostic and treatment processes arising from the adoption of clinical guidelines for diagnosis, treatment and in research methodologies, and availability of long-term follow-up data, have helped reduce the variations to a much improved 73 to 96% reported good outcomes. With careful evaluation, good patient selection, and advanced surgical techniques, iNPH can be surgically treated to return patients close to their pre-iNPH functional status. Institution of an interdisciplinary effort to rehabilitate patients following surgery may help augment their recovery.

Acute subdural hematomas in shunted normal-pressure hydrocephalus patients - Management options and literature review: A case-based series

Background:

Ventriculoperitoneal shunting (VPS) is considered a risk factor for developing subdural hematomas (SDH). Treating cases of acute SDH (aSDH) in shunted normal-pressure hydrocephalus (NPH) patients can be challenging, and data in this field are scarce. We report our experience treating shunted NPH patients presenting with aSDH.

Methods:

Eight patients, aged 73 ± 6 years, with a history of VPS for NPH, hospitalized because of aSDH were included in this study. We retrospectively analyzed data regarding patients’ clinical and radiological presentation, hospitalization course, the use of antithrombotics, and response to different treatment regimens.

Results:

Four patients had pure aSDH, three had acute on chronic SDH, and one had subacute SDH. Patients presented with GCS 13–15 and various neurological signs, mainly confusion and unsteady gate. Two cases improved following resetting of their programmable shunt valve to its maximal pressure setting. Six cases improved after evacuation of the hematomas, five of them were operated a few days after initially resetting of the valve pressure. Three patients were discharged home, whereas five were referred to rehabilitation. Extended Glasgow Outcome Scale scores at discharge and during long-term follow-up were 5 and 7, respectively.

Conclusions:

Treatment of patients with VPS for NPH, presenting with aSDH, may differ according to the neurological status, imaging, and clinical course. Treatment options include restricting shunt function, hematoma evacuation, or both.

Revisiting secondary normal pressure hydrocephalus: does it exist? A review

OBJECTIVE There are several etiologies that can lead to the development of secondary normal pressure hydrocephalus (sNPH). The aim of this study was to evaluate the etiology, diagnosis, treatment, and outcome in patients with sNPH and to highlight important differences between the separate etiologies. METHODS A comprehensive review of the literature was performed to identify studies conducted between 1965 and 2015 that included data regarding the etiology, treatment, diagnosis, and outcome in patients with sNPH. Sixty-four studies with a total of 1309 patients were included. The inclusion criteria of this study were articles that were written in English, included more than 2 patients with the diagnosis of sNPH, and contained data regarding the etiology, diagnosis, treatment, or outcome of NPH. The most common assessment of clinical improvement was based on the Stein and Langfitt grading scale or equivalent improvement on other alternative ordinal grading scales. RESULTS The main etiologies of sNPH were subarachnoid hemorrhage (SAH) in 46.5%, head trauma in 29%, intracranial malignancies in 6.2%, meningoencephalitis in 5%, and cerebrovascular disease in 4.5% of patients. In 71.9% of patients the sNPH was treated with ventriculoperitoneal shunt placement, and 24.4% had placement of a ventriculoatrial shunt. Clinical improvement after shunt placement was reported in 74.4% and excellent clinical improvement in 58% of patients with sNPH. The mean follow-up period after shunt placement was 13 months. Improvement was seen in 84.2% of patients with SAH, 83% of patients with head trauma, 86.4% of patients with brain tumors, 75% of patients with meningoencephalitis, and 64.7% of patients with NPH secondary to stroke. CONCLUSIONS Secondary NPH encompasses a diverse group of clinical manifestations associated with a subset of patients with acquired hydrocephalus. The most common etiologies of sNPH include SAH and traumatic brain injury. Secondary NPH does indeed exist, and should be differentiated from idiopathic NPH based on outcome and on clinical, pathophysiological, and epidemiological characteristics, but should not be considered as a separate entity.

Diagnosis and Treatment of Idiopathic Normal Pressure Hydrocephalus

PURPOSE OF REVIEW

This article provides neurologists with a pragmatic approach to the diagnosis and treatment of idiopathic normal pressure hydrocephalus (iNPH), including an overview of: (1) key symptoms and examination and radiologic findings; (2) use of appropriate tests to determine the patient's likelihood of shunt responsiveness; (3) appropriate referral to tertiary centers with expertise in complex iNPH; and (4) the contribution of neurologists to the care of patients with iNPH following shunt surgery.

RECENT FINDINGS

The prevalence of iNPH is higher than previously estimated; however, only a fraction of persons with the disorder receive shunt surgery. iNPH should be considered as a diagnosis for patients with unexplained symmetric gait disturbance, a frontal-subcortical pattern of cognitive impairment, and urinary urge incontinence, whose MRI scans show enlarged ventricles and whose comorbidities are not sufficient to explain their symptoms. Physiologically based tests, such as the tap test (large-volume lumbar puncture) or temporary spinal catheter insertion for external lumbar drainage with gait testing before and after CSF removal, or CSF infusion testing for measurement of CSF outflow resistance, can reliably identify patients who are likely to respond to shunt surgery. Properly selected patients have an 80% to 90% chance of responding to shunt surgery, and all symptoms can improve following shunt surgery. Longitudinal care involves investigating the differential diagnosis of any symptoms that either fail to respond to shunt surgery or that worsen after initial improvement from shunt surgery.

SUMMARY

Neurologists play an important role in the identification of patients who should be evaluated for possible iNPH. With contemporary diagnostic tests and treatment with programmable shunts, the benefit-to-risk ratio of shunt surgery is highly favorable. For more complex patients, tertiary centers with expertise in complex iNPH are available throughout the world.

Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) as a Cognitive Evaluation Tool for Patients with Normal Pressure Hydrocephalus

External lumbar drainage (ELD) is recognized as a screening method for ventriculo-peritoneal shunting (VPS) candidacy for possible normal pressure hydrocephalus (NPH). This study focused on the ELD predictability of the cognitive outcome after VPS for NPH. In addition, Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was examined in ELD cognition screening. ELD results were considered positive with any improvement in gait and/or cognition. Among 36 patients examined for possible NPH, 26 underwent VPS because of positive ELD. Cognitive outcome after VPS was assessed at 6-month follow-up. The RBANS scores, examined pre- and post-ELD, were evaluated statistically to identify consistency with the neuropsychologist judgment and the predictability of cognitive outcome after VPS. Among 26 shunted patients, gait was improved in 24. Cognitive improvement was rated in 19, and there were 9 false negative and 5 false positive in ELD cognition screening. The neuropsychologist judgment in ELD cognition screening is most consistent with the RBANS score in delayed memory. The patients rated as improved in cognition after VPS had significantly lower RBANS scores pre-ELD in immediate memory and delayed memory. If both scores at pre-ELD were ≤ 80 (13 patients), all were rated as improved in cognition after VPS. ELD screening was highly predictive of clinical gait improvement but not of cognitive improvement after VPS for possible NPH. Particularly among patients with a positive ELD gait response, pre-ELD low RBANS scores in memory predicted cognitive improvement after VPS. RBANS seems effective in evaluating cognition for NPH.

Aspirin is associated with an increased risk of subdural hematoma in normal-pressure hydrocephalus patients following shunt implantation

OBJECT

In this paper the authors investigate whether shunt-treated patients with normal-pressure hydrocephalus receiving aspirin therapy are at increased risk of developing subdural hematoma (SDH).

METHODS

Records from 80 consecutive patients who had undergone implantation of a cerebrospinal fluid shunt for the treatment of normal-pressure hydrocephalus were retrospectively reviewed.

RESULTS

Eleven cases of symptomatic SDH occurred, all among patients receiving aspirin or clopidogrel. The 5-year survival estimate was 0.3 (p < 0.0001) for users of aspirin and the hazard ratio was 12.8 (95% CI 3.1–53).

CONCLUSIONS

Patients on an aspirin therapy regimen have a markedly increased risk of SDH after a shunt has been implanted for the treatment of normal-pressure hydrocephalus. Users of clopidogrel may have an even greater risk.

An investigation into the clinical impacts of lowering shunt opening pressure in idiopathic normal pressure hydrocephalus: A case series

INTRODUCTION

Idiopathic normal pressure hydrocephalus (iNPH) is a shunt- reversible syndrome of the elderly. Shunt management is aimed at achieving a balance between clinical improvement and the complications associated with overdrainage. Although clinical improvement occurs at low pressure, these benefits may be negated by the increase in complication rates observed at lower pressures. The addition of gravity-switch devices has been shown to reduce over drainage problems even at a low valve pressure setting. At our centre the Miethke proGAV is used and commonly lowered below 5 cmH₂O to gain further clinical improvement.

OBJECT

To determine whether lowering the opening pressure to below 5cmH₂O using the proGAV valve in iNPH patients results in a) improved clinical features; and b) no significant increase in complication rates.

METHODS

A retrospective case series of iNPH patients was undertaken with 24 patients who had the proGAV shunt system inserted with an initial opening pressure of 5cmH₂O. Exclusion criteria were secondary NPH, shunt system other than proGAV inserted, no valve adjustment to below 5cmH₂O and inadequate follow-up. Outcome measures were clinical improvement (gait, cognition and urinary continence) and complications (subdural haematoma, low-pressure symptoms and valve damage).

RESULTS

Patients underwent a total of 29 adjustments to below 5cmH₂O. The mean valve opening pressure after the first adjustment was 2.5cmH₂O and the mean opening pressure after the second adjustment was 1cmH₂O. Overall, outcome after adjustment included 26% no change, 48% improvement and 26% deterioration clinically. One patient (4%) suffered traumatic subdural haematoma that resolved with increasing valve pressure to 20cmH₂O. There was no valve damage or low-pressure symptoms after adjustment.

CONCLUSION

This study found that lowering the opening pressure of the proGAV shunt system to below 5cmH₂O results in clinical improvement and does not significantly increase the complication rate in iNPH patients.

Diagnosis and management of idiopathic normal-pressure hydrocephalus

The diagnosis and management of idiopathic normal-pressure hydrocephalus (iNPH), a disorder of gait impairment, incontinence, and dementia that affects elderly patients, incorporates an organized approach using familiar principles for neurologists. The starting point is a comprehensive history and neurologic examination, review of neuroimaging, and evaluation of the differential diagnosis. Coexisting disorders should be treated before specific iNPH testing is performed. Specific iNPH testing includes assessing patient response to temporary CSF removal and testing CSF hydrodynamics. In properly selected patients, all iNPH symptoms, including dementia, can improve after shunt surgery. The longitudinal care of iNPH patients with shunts includes evaluation of the differential diagnosis of worsening iNPH symptoms and treatment of coexisting disorders. Evaluation of shunt obstruction is often indicated, and if it is found, surgical correction is likely to result in symptomatic improvement.

Use of the proGAV shunt valve in normal-pressure hydrocephalus

BACKGROUND

Overdrainage is a common complication associated with shunt insertion in normal-pressure hydrocephalus (NPH) patients. Using adjustable valves with antigravity devices has been shown to reduce its incidence. The optimal starting setting of an adjustable shunt valve in NPH is debatable.

OBJECTIVE

To audit our single-center practice of setting adjustable valves.

METHODS

We performed a retrospective review of clinical records of all NPH patients treated in our unit between 2006 and 2009 by the insertion of shunts with a proGAV valve, recording demographic and clinical data, shunt complications, and revision rates. Radiological reports of postoperative follow-up computed tomography scans of the brain were reviewed for detected subdural hematomas.

RESULTS

A proGAV adjustable valve was inserted in 50 probable NPH patients between July 2006 and November 2009. Mean ± SD age was 76 ± 7 years. Mean follow-up was 15 months. The initial shunt setting was 6 ± 3 cm H2O, and the final setting was 4.9 ± 1.9 cm H2O. Nineteen patients required 24 readjustment procedures (readjustment rate, 38%; readjustment number, 0.48 times per patient). One patient (2%) developed delayed bilateral subdural hematoma after readjustment of his shunt valve setting as an outpatient.

CONCLUSION

Starting with a low opening pressure setting on a proGAV adjustable shunt valve does not increase the chances of overdrainage complications and reduces the need for repeated readjustments.

Extended long-term (> 5 years) outcome of cerebrospinal fluid shunting in idiopathic normal pressure hydrocephalus

BACKGROUND

Shunt surgery has been established as the only durable and effective treatment for idiopathic normal pressure hydrocephalus.

OBJECTIVE

We evaluated the "extended" long-term follow-up (> 5 years) in a prospective study cohort who underwent shunting between 1990 and 1995. A secondary objective was to determine the cause of death in these patients.

METHODS

Fifty-one patients were included after confirmation of the diagnosis by extensive clinical and diagnostic investigations. Surgery included ventriculoatrial or ventriculoperitoneal shunting with differential pressure valves in the majority of patients. For each of the cardinal symptoms, postoperative outcome was assessed separately with the Krauss Improvement Index, yielding a value between 0 (no benefit) and 1 (optimal benefit) for the overall outcome.

RESULTS

Mean age at surgery was 70.2 years (range, 50-87 years). Thirty patients were women, and 21 were men. Short-term (18.8 +/- 16.6 months) follow-up was available for 50 patients. The Krauss Improvement Index was 0.66 +/- 0.28. Long-term (80.9 +/- 51.6 months) follow-up was available for 34 patients. The Krauss Improvement Index was 0.64 +/-0.33. Twenty-nine patients died during the long-term follow-up at a mean age of 75.8 years (range, 55-95 years). The major causes of death were cardiovascular disorders: cardiac failure (n = 7) and cerebral ischemia (n = 12). Other causes were pneumonia (n = 2), acute respiratory distress syndrome (n = 1), pulmonary embolism (n = 1), cancer (n = 2), renal failure (n = 1), and unknown (n = 3). There was no shunt-related mortality.

CONCLUSION

Idiopathic normal pressure hydrocephalus patients may benefit from shunting over the long term when rigorous selection criteria are applied. Shunt-related mortality is negligible. The main cause of death is vascular comorbidity.

Surgical management of adult hydrocephalus

The management of adult hydrocephalus spans a broad range of disorders and ages. Modern management strategies include endoscopic and adjustable cerebrospinal fluid shunt diversionary techniques. The assessment and management of the following clinical conditions are discussed: 1) the adult patient with congenital or childhood-onset hydrocephalus, 2) adult slit ventricle syndrome, 3) multicompartmental hydrocephalus, 4) noncommunicating hydrocephalus, 5) communicating hydrocephalus, 6) normal pressure hydrocephalus, and 7) the shunted patient with headaches. The hydrodynamics of cerebrospinal fluid shunt diversion are discussed in relation to mechanisms of under- and overdrainage conditions. A rationale for the routine implementation of adjustable valves for adult patients with hydrocephalus is provided based on objective clinical and experimental data. For the condition of normal pressure hydrocephalus, recommendations are offered regarding the evaluation, surgical treatment, and postoperative management of this disorder.

Diagnostic lumbar puncture: minimizing complications

Diagnostic lumbar puncture (LP) is essential to the diagnosis of central nervous system infections and subarachnoid haemorrhage. Life or limb-threatening adverse events due to the procedure are rare, but less severe complications may be common. Clinical practice in diagnostic LP is often not evidenced based. The aim of the study was to use best available published evidence to address questions on minimizing complications associated with diagnostic LP. We searched PubMed for studies in the English language using key words relevant to the complications of diagnostic LP. We emphasized randomized controlled trials and systematic reviews enrolling adult patients undergoing diagnostic LP. Uncontrolled studies and studies involving children or spinal anaesthesia were considered when no other evidence was available. There were nine prospective studies and three systematic reviews on reducing complications from LP. Recommendations on interventions to minimize complications of LP are graded based on the quality and strength of evidence.