[Possibilities of dynamic phase contrast MRI of cerebrospinal fluid for performing a tap test in a patient with idiopathic normotensive hydrocephalus]. / Vozmozhnosti dinamicheskoi fazovo-kontrastnoi MR-likvorografii pri vypolnenii tap-testa u patsienta s idiopaticheskoi normotenzivnoi gidrotsefaliei.

Idiopathic normotensive hydrocephalus (iNH) is a widespread disease in elderly patients. The effectiveness of iNG treatment and the subsequent quality of patients' lives directly depends on timely and early diagnosis. The criteria for diagnosing iNG that are used in neuroimaging can also be found in patients without clinical manifestations of this disease, and the widely used tap-test is an invasive technique with a rather low sensitivity. The need for early diagnosis and initiation of treatment before the development of irreversible damage to brain structures determines the relevance of the search for an accessible, minimally invasive, accurate and safe diagnostic method. The article presents a clinical observation of the use of phase-contrast MRI of cerebrospinal fluid (CSF) in a female patient with a positive response to the tap test with a quantitative analysis of changes in CSF flow parameters and ALVI and Evans indices depending on the time after CSF evacuation. Phase-contrast MRI of CSF with a quantitative assessment of CSF flow parameters in combination with an assessment of the ALVI index has the potential to increase the accuracy of diagnosing iNH and is of scientific interest for further research.

Magnetic Resonance Imaging Diagnosis in Normal Pressure Hydrocephalus.

BACKGROUND: Idiopatic normal pressure hydrocephalus (iNPH) is a progressive neurologic syndrome featured by the triad of gait disturbance, mental deterioration and urinary incontinence, associated with ventriculomegaly and normal cerebrospinal fluid (CSF) pressure. The clinical presentation may be atypical or incomplete, or mimicked by other diseases, so conventional neuroradiologic imaging plays an important role in defining this pathology. iNPH pathophysiologic mechanisms have not yet been fully elucidated, although several studies have demonstrated the involvement of the glymphatic system, a highly organized fluid transport system, the malfunction of which is involved in the pathogenesis of several disorders including normotensive hydrocephalus. METHODS: Recent studies have shown how crucial in the diagnosis of this pathology is the definition of morphologic biomarkers, such as ventricular enlargement disproportionate to cerebral atrophy and associated ballooning of frontal horns; periventricular hyperintensities; and corpus callosum thinning and elevation, with callosal angle <90 degrees. RESULTS: Another interesting feature that is becoming a well-recognized factor to look for and useful for the diagnosis of iNPH is disproportionately enlarged subarachnoid space hydrocephalus, which includes enlarged ventricles, tight high-convexity and medial surface subarachnoid spaces, and expanded Sylvian fissures. A correct choice of MRI sequences is important for a proper characterization identification of others diseases that may underlie this pathology. Magnetic resonance imaging allows us to evaluate CSF flow, enabling us to define qualitative and quantitative parameters necessary for the purpose of accurate iNPH diagnosis. CONCLUSIONS: iNPH can represent a real diagnostic challenge; a proper correlation among clinical features, traditional MRI, and CSF dynamics analysis can lead to a correct diagnosis.

Retraso del diagnóstico en un paciente con Hakim Adams / Delayed diagnosis in a patient with Hakim Adams

La hidrocefalia normotensiva es una patología caracterizada por alteración en la marcha, incontencia vesical, déficit cognitivo, hallazgos imagenológicos de ventriculomegalia comunicante y, presión normal de líquido cefalorraquídeo. Por la ambigüedad de sus síntomas y por la falta de criterios imagenológicos muy concluyentes es una patología de difícil diagnóstico inicial; el paciente muchas veces acude a distintos especialistas por síntomas aislados hasta que se relacionan los mismos y, se deriva el caso a Neurología / Neurocirugía. Se presenta el caso de un paciente de 65 años que presentó un cuadro de 2 años de evolución de incontinencia urinaria tratado como alteración de la micción secundaria a una hiperplasia prostática benigna sin mejoría alguna en ese intervalo de tiempo. Luego se agregó al cuadro una alteración en la marcha que fue poco valorada por el paciente y su entorno, sin ser conscientes del déficit cognitivo hasta que se realizó la evaluación neuropsicológica. Si bien el paciente presentaba la triada clásica que caracteriza a la hidrocefalia de presión normal, no fue hasta dos años luego del inicio del cuadro que se llegó al diagnóstico y, fue intervenido quirúrgicamente. Se colocó una válvula de derivación ventrículo peritoneal de presión media, con la cual presentó una evolución favorable y, resolución absoluta de los síntomas.

Normotensive hydrocephalus is a pathology characterized by impaired gait, bladder incontinence, cognitive deficit, images findings of communicating ventriculomegaly and normal cerebrospinal fluid pressure. Due to the ambiguity of its symptoms and the lack of conclusive images criteria, it is difficult initial diagnosis pathology; the patient often goes to different specialists for isolated symptoms until they are related, and the case is referred to Neurology / Neurosurgery. We present the case of a patient who presented a 2-year history of urinary incontinence treated as an alteration of urination secondary to a benign prostatic hyperplasia without any improvement in that time interval. Then a gait disturbance was added to the picture that was poorly valued by the patient and his environment, without being aware of the cognitive deficit until a neuropsychological evaluation. Although the patient presented the classic triad that characterizes normal pressure hydrocephalus, it was not until two years after the onset of the condition that the diagnosis was reached and underwent surgery. A peritoneal ventricular shunt of medium pressure was placed, presenting a favorable evaluation and complete resolution of symptoms.

Discriminant Analysis of Intracranial Volumetric Variables in Patients with Normal Pressure Hydrocephalus and Brain Atrophy.

A method was developed for the computerized volumetric assessment of the intracranial cerebrospinal fluid (CSF) distribution. The study involved 62 patients differentiated into two groups: with CSF resorption disorders (normal pressure hydrocephalus - 30 patients) and without CSF resorption disorders (various types of brain atrophy - 32 patients). The goal of the study was to ascertain whether the assessment, depending on the linear discriminant analysis of volumetric brain features, could be an effective tool differentiating the two groups. Volumetric measurements were performed using VisNow software. For each patient, five features were determined and subjected to discriminant analysis: CSF volume in the subarachnoid space and basal cisterns (SV), CSF volume in the intracranial ventricular system (VV), brain volume (BV), total intracranial CSF volume (FV), and total intracranial volume (TV). Discriminant analysis enables the achievement of a high percentage of correct classification of patients to the appropriate group determined on the result of a lumbar infusion test. The discriminator, based on three features: BV, SV, and VV, showed a complete separation of the groups; irrespective of age. The squared Mahalanobis distance was 70.8. The results confirmed the applicability of the volumetric method. Discriminant analysis seems a useful tool leading to the acquisition of a computer-aided method for the differential diagnosis of CSF resorption disorders.

Hidrocefalia De Presión Normal / Normal Pressure Hydrocephalus

Resumen La hidrocefalia de presión normal es una patología reversible que forma parte de las demencias. A pesar del tiempo que ha transcurrido desde su descubrimiento, su fisiopatología no ha sido claramente establecida y se han planteado dos teorías que buscan explicar el proceso. Una está basada en cambios en el flujo de líquido cefalorraquideo y la otra en el flujo sanguíneo cerebral. Además, el proceso de evaluación y diagnóstico no está determinado, puesto que no existe un método estándar y los síntomas son similares a otras patologías de sistema nervioso central, haciendo que el diagnóstico se realice gracias a la suma de los síntomas clínicos y ciertos hallazgos imagenológicos que no son siempre constantes.

Abstract Normal pressure hydrocephalus is a pathology causing dementia that is reversible. Despite the time elapsed since its discovery, its pathophysiology has not been clearly established and two theories have been proposed that try to explain the process, one based on changes in cerebrospinal fluid flow and the other on cerebral blood flow. In addition, the evaluation and diagnosis process is not determined, since there is no standard method and the symptoms are similar to other pathologies of the central nervous system, leading to the diagnosis as the summation of clinical symptoms and some findings in imaging which are not always constant.

CSF tap test - Obsolete or appropriate test for predicting shunt responsiveness? A systemic review.

OBJECTIVES: There is no accurate test for diagnosing normal pressure hydrocephalus or for screening for patients who will benefit from shunt surgery. Additional tests, such as cerebrospinal fluid tap test (CSF-TT), are often used in practice to provide further predictive value in detecting suitable patients for shunting. We performed a systematic review of the literature to evaluate the CSF-TT's effect on the outcome of main symptoms and on validity parameters in screening patients suitable for shunting. METHODS: In February 2015 we searched electronic databases from their inception to the current date, using the following key words: normal pressure hydrocephalus, idiopathic normotensive hydrocephalus, shunt operation, CSF tap test, predictive value, validity. The search retrieved 8 articles explicitly addressing the topic. RESULTS: There was a very high positive predictive value of CSF-TT: 92% (range from 73% to 100%) but a low negative predictive value: 37% (18%-50%). Also, the CSF-TT has high specificity: 75% (33%-100%) but average sensitivity: 58% (26%-87%). The overall accuracy of the test was 62% (45%-83%). CONCLUSIONS: This systematic review did not provide unambiguous validity of the CSF-TT in the screening of patients for shunting. The validity of the CSF-TT is good for patient inclusion for shunting due to the fact that the positive response to the test is very reliable. Unfortunately, the negative response to the test does not reliably make these patients ineligible for shunting. Further studies are needed to improve and standardize the methodology in order to optimize the detection power of the test.