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.

Guidelines for Management of Idiopathic Normal Pressure Hydrocephalus (Third Edition): Endorsed by the Japanese Society of Normal Pressure Hydrocephalus.

Among the various disorders that manifest with gait disturbance, cognitive impairment, and urinary incontinence in the elderly population, idiopathic normal pressure hydrocephalus (iNPH) is becoming of great importance. The first edition of these guidelines for management of iNPH was published in 2004, and the second edition in 2012, to provide a series of timely, evidence-based recommendations related to iNPH. Since the last edition, clinical awareness of iNPH has risen dramatically, and clinical and basic research efforts on iNPH have increased significantly. This third edition of the guidelines was made to share these ideas with the international community and to promote international research on iNPH. The revision of the guidelines was undertaken by a multidisciplinary expert working group of the Japanese Society of Normal Pressure Hydrocephalus in conjunction with the Japanese Ministry of Health, Labour and Welfare research project. This revision proposes a new classification for NPH. The category of iNPH is clearly distinguished from NPH with congenital/developmental and acquired etiologies. Additionally, the essential role of disproportionately enlarged subarachnoid-space hydrocephalus (DESH) in the imaging diagnosis and decision for further management of iNPH is discussed in this edition. We created an algorithm for diagnosis and decision for shunt management. Diagnosis by biomarkers that distinguish prognosis has been also initiated. Therefore, diagnosis and treatment of iNPH have entered a new phase. We hope that this third edition of the guidelines will help patients, their families, and healthcare professionals involved in treating iNPH.

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.