High prevalence of cervical myelopathy in patients with idiopathic normal pressure hydrocephalus

High prevalence of lumbar spinal stenosis in cases of idiopathic normal-pressure hydrocephalus affects improvements in gait disturbance after shunt operation

Objective

Idiopathic normal-pressure hydrocephalus (iNPH) is characterized by symptoms of dementia, urinary incontinence, and gait disturbance; however, gait disturbance tends to persist after shunt surgery. Gait disturbance and urinary dysfunction are also major symptoms of lumbar spinal stenosis (LSS). Currently, the epidemiology of the complications of LSS in iNPH is unclear. Here, we evaluated the coexistence rate of LSS in iNPH cases.

Methods

This was a retrospective case-control study. Between 2011 and 2017, 224 patients with a median age of 78 years, including 119 males, were diagnosed with iNPH and underwent lumboperitoneal shunts or ventriculoperitoneal shunts. LSS was diagnosed with magnetic resonance imaging by two spine surgeons. Age, sex, body mass index (BMI), Timed Up and Go (TUG) test, Mini Mental State Examination (MMSE) score, and urinary dysfunction were examined. We compared the changes in these variables in the group of patients with iNPH without LSS versus those with both iNPH and LSS.

Results

Seventy-three iNPH patients (32.6%) with LSS had significantly higher age and BMI. The existence of LSS did not alter the postoperative improvement rates of MMSE and urinary dysfunction; however, TUG improvement was significantly impaired in the LSS-positive group.

Conclusions

LSS affects improvements in gait disturbance of iNPH patients after shunt operation. Because our results revealed that one-third of iNPH patients were associated with LSS, gait disturbance observed in iNPH patients should be considered a potential complication of LSS.

Hydrocephalus: A neuropsychological and theoretical primer

Hydrocephalus is a common neurological condition, the hallmark feature of which is an excess in production, or accumulation, of cerebrospinal fluid in the ventricles. Although it is associated with diffuse damage to paraventricular brain areas, patients are broadly typified by a particular pattern of cognitive impairments that include deficits in working memory, attention, and spatial abilities. There have, however, been relatively few neuropsychological accounts of the condition. Moreover, theories of the relationship between aetiology and impairment appear to have emerged in isolation of each other, and proffer fundamentally different accounts. In this primer, we aim to provide a comprehensive and contemporary overview of hydrocephalus for the neuropsychologist, covering cognitive sequelae and theoretical interpretations of their origins. We review clinical and neuropsychological assays of cognitive profiles, along with the few studies that have addressed more integrative behaviours. In particular, we explore the distinction between congenital or early-onset hydrocephalus with a normal-pressure variant that can be acquired later in life. The relationship between these two populations is a singularly interesting one in neuropsychology since it can allow for the examination of typical and atypical developmental trajectories, and their interaction with chronic and acute impairment, within the same broad neurological condition. We reflect on the ramifications of this for our subject and suggest avenues for future research.

The Role of Simultaneous Medical Conditions in Idiopathic Normal Pressure Hydrocephalus

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) is a chronic neurologic syndrome that affects the elderly population in a context of concomitant medical conditions. The aim of this study was to understand the significance of comorbidities using 4 validated and specific clinical scores: Cumulative Illness Rating Scale (CIRS), American Society of Anesthesiologists (ASA) score, Comorbidity Index (CMI), and Charlson Comorbidity Index (CCI).

METHODS

From 2015 until 2019, the Bologna PRO-Hydro multidisciplinary team selected 63 patients for shunt surgery. All comorbidity scores were collected during preoperative anesthesia evaluation. Positive shunt response was defined as an improvement in overall disability (assessed with modified Rankin Scale [mRS]), in risk of fall (assessed with Tinetti Permormance Orientated Mobility Assessment, Tinetti) and in INPH specific symptoms (assessed with INPH Grading Scale, INPHGS).

RESULTS

Patients with elevated values of CIRS had worse performance in gait and balance at Tinetti scale, both before (P = 0.039) and after surgery (P = 0.005); patients with high values of CMI had inferior values of Tinetti at baseline (P = 0.027) and higher mRS after surgery (P = 0.009); ASA 2 patients had better postoperative Tinetti scores than ASA 3 patients (P = 0.027). A positive or negative shunt response was not significantly correlated with patients' preoperative comorbidity scores.

CONCLUSIONS

Patients with multiple comorbidities have a worse preoperative condition compared to patients with less concomitant diseases, and the proposed comorbidity scores, CIRS in particular, are useful clinical tools for the anesthesiologist. Comorbidities, though, do not impact overall postoperative outcome.

Acute Quadriplegia after Lumbar Puncture in a Patient with Misdiagnosed Cervical Myelopathy

The incidence of quadriplegia following drainage of cerebrospinal fluid by lumbar puncture (LP) below a spinal occupying lesion is rare. We report a case of acute quadriplegia following LP for presumed normal pressure hydrocephalus (NPH) in a 66-year-old man. Acute cervical myelopathy with a herniated cervical disc was subsequently found on magnetic resonance imaging (MRI) at the C5–6 level. After posterior decompression and anterior cervical discectomy and fusion at the C5–6 level with a cervical plate, the patient's motor and sensory functions recovered. Clinicians should be aware that symptoms of NPH and cervical myelopathy may overlap, and that serious complications may occur when performing LP below a spinal lesion. As a safety measure, cervical spine MRI should be performed before LP.