Preoperative factors associated with shunt responsiveness in patients with idiopathic normal-pressure hydrocephalus.

OBJECTIVE: We aimed to evaluate a possible association between preoperative factors (disease duration and vascular risk factors) and shunt responsiveness in patients with idiopathic normal-pressure hydrocephalus (iNPH). METHODS: We conducted a retrospective observational study in a high-volume center for iNPH treatment in Japan and reviewed the clinical data of 107 consecutive patients with probable iNPH who underwent shunt surgery between January 1, 2018, and August 31, 2019, and were followed up for at least 12 months after surgery. Preoperatively, these patients underwent the timed up-and-go test (TUG) and Mini-Mental State Examination (MMSE); moreover, follow-up evaluations were performed 12 months postoperatively, at which TUG and MMSE scores were used as metrics for shunt responsiveness assessment. The degree of shunt responsiveness was regressed to several preoperative factors, including preoperative TUG and MMSE scores, vascular risk factors, and duration from iNPH onset to shunt surgery, to evaluate which preoperative factors may be predictive of shunt responsiveness. RESULTS: In multivariate regression analysis, there was no statistically significant association between the presence of preoperative vascular risk factors and the postoperative TUG or MMSE score 12 months after shunt surgery. Meanwhile, preoperative history of ischemic stroke and a longer duration from iNPH onset to surgery were significantly associated with poorer shunt responsiveness in terms of MMSE and TUG scores. CONCLUSIONS: The current study suggested the potential involvement of stroke history and disease duration with the 1-year prognosis of iNPH after shunt surgery, of which validity needs to be corroborated in further studies.

[Lumbo-Peritoneal Shunt for Patients with Idiopathic Normal Pressure Hydrocephalus:Surgical Technique].

The SINPHONI-2 study(a group of Japanese prospective multicenter cohort studies on the treatment of idiopathic normal pressure hydrocephalus[iNPH])showed the safety and efficacy of lumboperitoneal(L-P)shunt surgery for iNPH. A total of 660 probable iNPH patients underwent L-P shunt surgery at our NPH center between April 2009 and March 2020(age: 77.3 ± 6.2 years). Our surgical technique includes 1)general anesthesia, 2)use of the original drape, 3)upward insertion of the spinal tube through L2/3 via a paramedian puncture in patients with highly deformed lumbar spines, 4)posterior placement of a Codman Hakim programmable valve with SiphonguardTM, 5)inclination of the table at a 35° angle without position change and re-sterilization, 6)laparotomy via rectal muscle splitting, and 7)oblique maneuvering the peritoneal tube from the upper lateral to the lower medial sector. During the first year after surgery, postoperative complications occurred in 14 of 172 patients (8.1%), including four patients with chronic subdural hematoma requiring evacuation (2.3%), three with spinal tube occlusion (1.7%), three with migration of the spinal tube, two with lower-limb numbness (1.2%), and two with abdominal tube occlusion. Our L-P shunt procedure seems to be generally acceptable considering the low number of complications.

Effect of cerebrospinal fluid shunt surgery on lower urinary tract dysfunction in idiopathic normal pressure hydrocephalus.

AIMS: To examine the outcomes of lower urinary tract symptoms (LUTS) and urodynamic test results after cerebrospinal fluid (CSF) shunt surgery in idiopathic normal pressure hydrocephalus (iNPH). METHODS: Records of 48 patients (33 men; 15 women), who met the definite iNPH criteria and underwent CSF shunt surgery, were retrospectively analyzed. LUTS and their impact on quality of life (QOL) were evaluated using an all-or-none questionnaire targeting four symptoms, the Overactive Bladder Symptoms Score (OABSS), and the QOL index. Urodynamic investigations included filling cystometry and pressure-flow studies performed before and after surgery. RESULTS: Forty-seven (98%) patients complained of LUTS, 41 (87%) patients of whom experienced LUTS improvement after surgery. The OABSS and QOL index, which before surgery were 6.8 ± 0.7 and 4.1 ± 0.4, respectively, significantly decreased to 4.6 ± 0.6 and 3.2 ± 0.3, respectively, after surgery. The maximum cystometric capacity (174.9 ± 13.3 mL to 222.4 ± 14.7 mL) and bladder compliance (35.8 ± 4.4 ml/cmH2 O to 52.1 ± 5.4 ml/cmH2 O) significantly increased after surgery. Detrusor overactivity, which was observed in 37 (77%) patients preoperatively, became undetectable in 7 patients postoperatively. Voiding dysfunction (defined as maximum flow rate <10 mL/s or post-void residual >100 mL) was observed in 29 (60%) patients, 22 (75%) of whom had detrusor underactivity before surgery. None of the voiding urodynamic parameters significantly improved postoperatively. CONCLUSIONS: iNPH is often associated with LUTS and both storage and voiding dysfunctions. CSF shunt surgery improved LUTS and storage dysfunction, with limited effects on voiding dysfunction.

A Segmental Copy Number Loss of the SFMBT1 Gene Is a Genetic Risk for Shunt-Responsive, Idiopathic Normal Pressure Hydrocephalus (iNPH): A Case-Control Study.

Little is known about genetic risk factors for idiopathic normal pressure hydrocephalus (iNPH). We examined whether a copy number loss in intron 2 of the SFMBT1 gene could be a genetic risk for shunt-responsive, definite iNPH. Quantitative and digital PCR analyses revealed that 26.0% of shunt-responsive definite iNPH patients (n = 50) had such a genetic change, as compared with 4.2% of the healthy elderly (n = 191) (OR = 7.94, 95%CI: 2.82-23.79, p = 1.8 x 10-5) and 6.3% of patients with Parkinson's disease (n = 32) (OR = 5.18, 95%CI: 1.1-50.8, p = 0.038). The present study demonstrates that a copy number loss within intron 2 of the SFMBT1 gene may be a genetic risk factor for shunt-responsive definite iNPH.

The value of the cerebrospinal fluid tap test for predicting shunt effectiveness in idiopathic normal pressure hydrocephalus.

BACKGROUND: The cerebrospinal fluid (CSF) tap test (TT) has been regarded as an important test for the prediction of shunt effectiveness in patients with suspected idiopathic normal pressure hydrocephalus (iNPH). Although its specificity and sensitivity are reportedly high, there remains some disagreement over this point. Herein, the TT as a test for predicting shunt effectiveness was investigated in our multicenter prospective study named SINPHONI and strategies to increase its predictability were examined. METHODS: One hundred suspected iNPH patients with the following entry criteria were enrolled in the study: (1) 60 to 85 years old, (2) one or more of the NPH triad signs, (3) ventriculomegaly (Evans index > 0.3), (4) high convexity tightness in coronal-section MRI, and (5) no antecedent disorders. Changes in NPH triad symptoms were assessed using the iNPH grading scale and other measures before and after removal of 30 ml lumbar CSF. A positive response to TT was pre-defined by specific improvements on the grading and other scales. A ventriculoperitoneal shunt was performed with a programmable valve. The sensitivity and specificity of the TT was calculated with a contingency table. A decision tree analysis was performed to increase the predictability of the TT. RESULTS: Among 100 patients, 80 were shunt responders. A statistically-significant variable between shunt responders and non-responders was CSF pressure. The changes in single variables in the iNPH grading scale after TT showed high specificity with low sensitivity. In contrast, change of the total score in the iNPH grading scale showed a relatively high sensitivity of 71.3% with specificity of 65%. A decision tree analysis revealed that using the iNPH grading scale total score and pre-shunt CSF pressure ≥ 15 cmH20, sensitivity increased to 82.5%, without a decrease in specificity. CONCLUSIONS: The sensitivity and specificity of the TT for predicting shunt responsiveness were optimum when improvement on any iNPH grading scale was combined with CSF pressure ≥ 15 cmH20. To increase the sensitivity of the TT, further effort is necessary. TRIAL REGISTRATION: This study is registered with ClinicalTrials.gov, with the number NCT00221091.

Diagnosis of idiopathic normal pressure hydrocephalus is supported by MRI-based scheme: a prospective cohort study.

BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a treatable neurological syndrome in the elderly. Although the magnetic resonance imaging (MRI) findings of tight high-convexity and medial subarachnoid spaces and the ventriculo-peritoneal (VP) shunt with programmable valve are reportedly useful for diagnosis and treatment, respectively, their clinical significance remains to be validated. We conducted a multicenter prospective study (Study of Idiopathic Normal Pressure Hydrocephalus on Neurological Improvement: SINPHONI) to evaluate the utility of the MRI-based diagnosis for determining the 1-year outcome after VP shunt with the Codman-Hakim programmable valve. METHODS: Twenty-six centers in Japan were involved in this study. Patients aged between 60 and 85 years with one or more of symptoms (gait, cognitive, and urinary problems) and MRI evidence of ventriculomegaly and tight high-convexity and medial subarachnoid spaces received VP shunt using the height/weight-based valve pressure-setting scheme. The primary endpoint was a favorable outcome (improvement of one level or more on the modified Rankin Scale: mRS) at one year after surgery, and the secondary endpoints included improvement of one point or more on the total score of the iNPH grading scale. Shunt responder was defined by more than one level on mRS at any evaluation point in one year. RESULTS: The full analysis set included 100 patients. A favorable outcome was achieved in 69.0% and 80.0% were shunt responders. When measured with the iNPH grading scale, the one-year improvement rate was 77.0%, and response to the surgery at any evaluation point was detected in 89.0%. Serious adverse events were recorded in 15 patients, three of which were events related to surgery or VP shunt. Subdural effusion and orthostatic headache were reported as non-serious shunt-related adverse events, which were well controlled with readjustment of pressure. CONCLUSIONS: The MRI-based diagnostic scheme is highly useful. Tight high-convexity and medial subarachnoid spaces, and enlarged Sylvian fissures with ventriculomegaly, defined as disproportionately enlarged subarachnoid-space hydrocephalus (DESH), are worthwhile for the diagnosis of iNPH. This study is registered with ClinicalTrials.gov, number NCT00221091.

Acute lung injury associated with systemic inflammatory response syndrome following subarachnoid hemorrhage: a survey by the Shonan Neurosurgical Association.

Acute lung injury (ALI) associated with systemic inflammatory response syndrome (SIRS) is a systemic complication following subarachnoid hemorrhage (SAH), but the incidence and influence on prognosis are unclear. The incidences of SIRS and ALI were surveyed in a prospective multicenter study of 96 patients admitted for SAH between December 2004 and June 2007. Hunt and Hess grade and Glasgow Outcome Scale score were also investigated. Forty-eight patients were diagnosed with SIRS, and 26 developed ALI within 4 weeks of admission. Nineteen of the 26 patients with ALI were complicated by SIRS, and 7 developed only ALI. Thirteen of the 19 patients complicated by SIRS and ALI died, and this mortality was higher than for patients with only SIRS (3/29) and only ALI (1/7). Multivariate analysis of the development of SIRS and/or ALI and Hunt and Hess grade as risk factors associated with aggravation of the outcome showed that complication with SIRS and ALI had the highest risk. Half of the patients admitted for SAH developed SIRS, and more than 25% developed ALI. The prognosis for patients complicated by SIRS and ALI was poor, which indicates that prevention and active treatment of these two pathologies are important.

Guidelines for management of idiopathic normal pressure hydrocephalus.

With the rapid aging of Japanese society, medical care of the elderly has become an important social issue. Among various disorders manifesting dementia, gait disturbance, and urinary incontinence in the elderly population, normal pressure hydrocephalus (NPH), especially of idiopathic type (iNPH), is becoming noteworthy. The Guidelines for management of iNPH in Japan are created in compliance with the evidence-based medicine methods and published in 2004. This English version is made to show the diagnosis and treatment of iNPH with reference to the socio-medical background in Japan and to promote the international research on iNPH. They propose three diagnostic levels; possible, probable, and definite. They indicate the diagnostic importance of high convexity tightness and dilated sylvian fissure with mild to moderate ventriculomegaly on coronal magnetic resonance imaging. The cerebrospinal fluid tap test is regarded as an important diagnostic test because of its simplicity to perform and high predictability of the shunt efficacy. The use of programmable valves at shunt surgeries is recommended. Flowcharts for diagnosis, preoperative assessment, and prevention for complications of shunt surgery are made to promote a wide use of them.

Cerebral haemodynamics in patients with hydrocephalus after subarachnoid haemorrhage due to ruptured aneurysm.

Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) may be reduced in patients with normal pressure hydrocephalus (NPH) after subarachnoid haemorrhage (SAH). However, little is known about brain circulation in asymptomatic patients with ventriculomegaly after SAH. This study investigated CBF and CVR in symptomatic and asymptomatic patients with ventriculomegaly to clarify the mechanism of NPH. CBF and CVR were investigated in 48 patients with ventriculomegaly after SAH due to ruptured aneurysm. Mean CBF of the whole brain was measured by first-pass radionuclide angiography using technetium-99m hexamethylpropylene amine oxime. CVR was measured as the percentage change from the baseline mean CBF value after administration of 500 mg acetazolamide. Thirty patients with NPH who responded to shunting had significantly ( P<0.01) reduced mean CBF and CVR compared with normal controls. Fourteen asymptomatic patients with ventriculomegaly showed significant ( P<0.01) reduction in CVR but no difference in mean CBF. Four symptomatic patients who did not respond to shunting showed significantly ( P<0.01) reduced mean CBF but had preserved CVR. Postoperative mean CBF and CVR increased significantly ( P<0.01) in 21 patients who responded to shunting, but showed no significant change in four symptomatic patients who did not respond to shunting. Reduction of CBF superimposed on pre-existing impairment of CVR may be an essential step in the mechanism responsible for the manifestation of symptoms of NPH.