B-mode transorbital ultrasonography for the diagnosis of idiopathic intracranial hypertension: an updated systematic review and meta-analysis.

OBJECTIVES: This systematic review and meta-analysis aimed to evaluate the role of B-mode transorbital ultrasonography (TOS) for the diagnosis of idiopathic intracranial hypertension (IIH) in adults. METHODS: MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) (1966-May 2022) were searched to identify studies reporting ultrasonographic data about the optic nerve sheath diameter (ONSD) and optic disc elevation (ODE) in adults with IIH compared to subjects without IIH. The quality of the included studies was evaluated by the Newcastle-Ottawa Quality. RESULTS: Fifteen studies were included (total of 439 patients). The values of ODE ranged from 0.6 to 1.3 mm in patients with IIH. The values of ONSD ranged from 4.7 to 6.8 mm in IIH patients and from 3.9 to 5.7 mm in controls. In IIH patients, the ONSD was significantly higher compared to controls (standardized mean difference: 2.5 mm, 95% confidence interval (CI): 1.6-3.4 mm). Nine studies provided data about the presence of papilledema and the pooled prevalence was 95% (95% CI, 92-97%). CONCLUSIONS: In adults, the thickness of ONSD and the entity of ODE were significantly associated with IIH. B-mode TOS enables to noninvasively detect increased ICP and should be performed, potentially routinely, in any patient with suspected IIH.

Autoimmune encephalitis during pregnancy: A diagnostic and therapeutic challenge-A systematic review with individual patients' analysis and clinical recommendations.

Several reports have described the autoimmune encephalitis' (AE) possible onset during pregnancy. In this systematic review, we summarize the available data on the diagnostic and therapeutic approach to AE during pregnancy, highlighting the associated maternal and fetal clinical outcomes. A systematic search of the literature was performed. The following databases were used: PubMed, Google Scholar, EMBASE, and CrossRef. The revision was registered on the PROSPERO platform (CRD42022336357). Forty-nine patients were included. AE onset was mainly observed during the first and the second trimester of pregnancy with psychiatric manifestations and seizures as main onset symptoms. CSF analysis showed AE-specific autoantibody positivity in 33 patients (anti-NMDA receptor as the most frequent). EEG generally showed normal findings. MRI revealed pathological findings in less than half of patients. Tumor screening was positive in 14 cases. First-line immunotherapy (single or combined) was generally employed while second line was administered in a minority of patients. Levetiracetam was the most used antiseizure medication. Cesarean section was performed in 18 women. Most of the women had an excellent early outcome after delivery but 22 showed persistent neurological deficits in long-term follow-up. Fetal outcome was positive in 33 cases, whereas 12 cases of fetal death were reported. A logistic regression showed that no variable significantly influenced the odds of good/bad maternal and fetal clinical outcome. Diagnosis and treatment of AE during pregnancy is challenging. The rate of miscarriage in women with AE seems to be higher than the general population. In addition, mothers may show long-term neurological deficits.

Adult epilepsy.

Epilepsy is a common medical condition that affects people of all ages, races, social classes, and geographical regions. Diagnosis of epilepsy remains clinical, and ancillary investigations (electroencephalography, imaging, etc) are of aid to determine the type, cause, and prognosis. Antiseizure medications represent the mainstay of epilepsy treatment: they aim to suppress seizures without adverse events, but they do not affect the underlying predisposition to generate seizures. Currently available antiseizure medications are effective in around two-thirds of patients with epilepsy. Neurosurgical resection is an effective strategy to reach seizure control in selected individuals with drug-resistant focal epilepsy. Non-pharmacological treatments such as palliative surgery (eg, corpus callosotomy), neuromodulation techniques (eg, vagus nerve stimulation), and dietary interventions represent therapeutic options for patients with drug-resistant epilepsy who are not suitable for resective brain surgery.

Analysis of Clinical and Laboratory Risk Factors of Post-Traumatic Intracranial Hemorrhage in Patients on Direct Oral Anticoagulants with Mild Traumatic Brain Injury: An Observational Multicenter Cohort.

BACKGROUND: Assessing the risk of intracranial hemorrhage (ICH) in patients with a mild traumatic brain injury (MTBI) who are taking direct oral anticoagulants (DOACs) is challenging. Currently, extensive use of computed tomography (CT) is routine in the emergency department (ED). OBJECTIVE: This study aims to investigate whether the clinical and laboratory characteristics presented at the ED evaluation can also estimate the risk of post-traumatic ICH in DOAC-treated patients with MTBI. METHODS: A retrospective observational study was conducted in three EDs in Italy from January 1, 2016 to March 15, 2020. All patients treated with DOACs who were evaluated for an MTBI in the ED were enrolled. The primary outcome of the study was the presence of post-traumatic ICH in the head CT performed in the ED. RESULTS: Of 930 patients on DOACs with MTBI who were enrolled, 6.8% (63 of 930) had a post-traumatic ICH and 1.5% (14 of 930) were treated with surgery or died as a result of the ICH. None of the laboratory factors were associated with an increased risk of ICH. On multivariate analysis, previous neurosurgical intervention, major trauma dynamic, post-traumatic loss of consciousness, post-traumatic amnesia, Glasgow Coma Scale score of 14, and evidence of trauma above the clavicles were associated with a higher risk of post-traumatic ICH. The net clinical benefit provided by risk factor assessment appears superior to the strategy of performing CT on all DOAC-treated patients. CONCLUSIONS: Assessment of the clinical characteristics presented at ED admission can help identify DOAC-treated patients with MTBI who are at risk of ICH.

Physicians' beliefs about brain surgery for drug-resistant epilepsy: A global survey.

PURPOSE: To investigate the opinions of physicians about brain surgery for drug-resistant epilepsy worldwide. METHODS: Practicing neurologists, psychiatrists, and neurosurgeons from around the world were invited to participate in an online survey. The survey anonymously collected data about demographics, years in clinical practice, discipline, nation, work setting, and answers to the questions about beliefs and attitudes about brain surgery for drug-resistant epilepsy. RESULTS: In total, 1410 physicians from 20 countries and different world regions participated. The propensity to discuss brain surgery with patients, who have drug-resistant seizures, was higher among men (versus women) [Odds Ratio (OR) 1.67, 95% CI 1.20-2.31; p = 0.002]. In comparison to neurologists, psychiatrists were less likely (OR 0.28, 95% CI 0.17-0.47; p < 0.001) and neurosurgeons were more likely (OR 2.00, 95% CI 1.08-3.72; p = 0.028) to discuss about it. Survey participants working in Africa, Asia, the Middle East, and the Former Union of Soviet Socialist Republics showed a lower propensity to discuss epilepsy surgery with patients. CONCLUSION: This study showed that on an international level, there is still a knowledge gap concerning epilepsy surgery and much needs to be done to identify and overcome barriers to epilepsy surgery for patients with drug-resistant seizures worldwide.

Embolic Stroke Following Ingestion of Liquid Nicotine Refill Solution.

The use of e-cigarettes is gaining popularity despite knowing about cardiovascular health risks. Cases of intentional or accidental intoxication following ingestion of the refill solution are also a growing concern. Most of these cases were fatal and related to cardiac arrest and hypoxic brain injury. We report the case of a 54-year-old woman who developed bilateral acute ischemic stroke in the anterior and posterior cerebral circulation following intentional oral intake of e-liquid nicotine refill solution. The diagnostic work-up concluded an etiology of embolic stroke of undetermined source, most likely of cardiac origin. We assume that sympathetic overactivation lead to temporary cardiac arrhythmia and subsequent thrombi formation. Moreover, we discuss several additional pathogenic aspects of oral intake of e-liquid refill solution for the development of central nervous system pathology. This case expands the clinical spectrum of health hazards associated with the introduction of e-cigarettes and raises awareness of the need for preventive measures.

Development and Validation of a Nomogram Based on the Epidemiology-Based Mortality Score in Status Epilepticus (EMSE) Parameters to Predict 30-day Mortality in Status Epilepticus.

BACKGROUND: To develop a nomogram using the parameters of the Epidemiology-Based Mortality Score in Status Epilepticus (EMSE) and to evaluate its accuracy compared with the EMSE alone in the prediction of 30-day mortality in patients with status epilepticus (SE). METHODS: We included a cohort of patients with SE aged ≥ 21 years admitted from 2013 to 2021. Regression coefficients from the multivariable logistic regression model were used to generate a nomogram predicting the risk of 30-day mortality. Discrimination of the nomogram was evaluated using the area under the receiver operating characteristic curve (AUCROC) with 95% confidence interval. Internal validation was performed by bootstrap resampling. RESULTS: Among 698 patients with SE, the 30-day mortality rate was 28.9% (202 of 698). On the multivariable analysis, all EMSE parameters (except for the comorbidity group including metastatic solid tumor or AIDS) were associated with a significantly higher risk of 30-day mortality and were included in the nomogram. The discriminatory capability of the nomogram with bootstrap resampling (5000 resamples) had an AUCROC of 0.830 (95% confidence interval 0.798-0.862). Conversely, the AUCROC of the EMSE was 0.777 (95% confidence interval 0.742-0.813). Thus, the probability that a patient who died within 30 days from SE had a higher score than a patient who survived was 83%, indicating good discriminatory power of the nomogram. Conversely, the risk predicted using the EMSE alone was 77%. The nomogram was well calibrated. CONCLUSIONS: A nomogram based on EMSE parameters appears superior to the EMSE in predicting the risk of 30-day mortality after SE. The discrimination and calibration of the nomogram shows a better predictive accuracy than the EMSE alone.

The Manchester Triage System's performance in clinical risk prioritisation of patients presenting with headache in emergency department: A retrospective observational study.

OBJECTIVE: Non-traumatic headache is a frequent reason for visits to the emergency department (ED). We evaluated the performance of the Manchester Triage System (MTS) in prioritising patients presenting to the ED with non-traumatic headache. METHODS: In this single-centre observational retrospective study, we compared the association of MTS priority classification codes with a final diagnosis of a severe neurological condition requiring timely management (ischaemic or haemorrhagic stroke, subarachnoid haemorrhage, cerebral sinus venous thrombosis, central nervous system infection or brain tumour). The study was conducted and reported according to the STROBE statement. The overall prioritisation accuracy of MTS was estimated by the area under the receiver operating characteristic (ROC) curve. The correctness of triage prediction was estimated based on the "very urgent" MTS grouping. An undertriage was defined as a patient with an urgent and severe neurological who received a low priority/urgency MTS code (green/yellow). RESULTS: Over 30 months, 3002 triage evaluations of non-traumatic headache occurred (1.7% of ED visits). Of these, 2.3% (68/3002) were eventually diagnosed with an urgent and severe neurological condition. The MTS had an acceptable prioritisation accuracy, with an area under the ROC curve of 0.734 (95% CI 0.668-0.799). The sensitivity of the MTS for urgent codes (yellow, orange and red) was 79.4% (95% CI 74.5-84.3), with a specificity of 54.1% (95% CI 52.9-55.3). The triage prediction was incorrect in only 6.3% (190/3002) of patients with headache. CONCLUSION: The MTS is a safe and accurate tool for prioritising patients with non-traumatic headache in the ED. However, MTS may need further specific tools for evaluating the more complicated symptoms and for correctly identifying patients with urgent and severe underlying pathologies. RELEVANCE TO CLINICAL PRACTICE: The triage nurse using MTS may need additional tools to improve the assessment of patients with headache, although MTS provides a good safety profile.

Unraveling the enigma of new-onset refractory status epilepticus: a systematic review of aetiologies.

BACKGROUND AND PURPOSE: New-onset refractory status epilepticus (NORSE) is a clinical presentation, neither a specific diagnosis nor a clinical entity. It refers to a patient without active epilepsy or other pre-existing relevant neurological disorder, with a NORSE without a clear acute or active structural, toxic or metabolic cause. This study reviews the currently available evidence about the aetiology of patients presenting with NORSE and NORSE-related conditions. METHODS: A systematic search was carried out for clinical trials, observational studies, case series and case reports including patients who presented with NORSE, febrile-infection-related epilepsy syndrome or the infantile hemiconvulsion-hemiplegia and epilepsy syndrome. RESULTS: Four hundred and fifty records were initially identified, of which 197 were included in the review. The selected studies were retrospective case-control (n = 11), case series (n = 83) and case reports (n = 103) and overall described 1334 patients both of paediatric and adult age. Aetiology remains unexplained in about half of the cases, representing the so-called 'cryptogenic NORSE'. Amongst adult patients without cryptogenic NORSE, the most often identified cause is autoimmune encephalitis, either non-paraneoplastic or paraneoplastic. Infections are the prevalent aetiology of paediatric non-cryptogenic NORSE. Genetic and congenital disorders can have a causative role in NORSE, and toxic, vascular and degenerative conditions have also been described. CONCLUSIONS: Far from being a unitary condition, NORSE is a heterogeneous and clinically challenging presentation. The development and dissemination of protocols and guidelines to standardize diagnostic work-up and guide therapeutic approaches should be implemented. Global cooperation and multicentre research represent priorities to improve the understanding of NORSE.

Camillo Negro (1861-1927) and Antonio Carle (1854-1927): Pioneers of non-resective surgical approach to epilepsy treatment.

Epilepsy surgery developed following the clinical and experimental demonstration of the existence of the primary motor cortex in animals and humans. The first epilepsy surgery procedures were mainly performed to treat focal motor (Jacksonian) epilepsy, as the seizure semiology precisely pointed to the contralateral motor cortex (epileptogenic zone), guiding the surgical removal of the visible lesion found in that region. However, mainly in the absence of any visible alteration of brain tissue, the removal of the portion of the cortex supposed to be responsible for the seizures carried the risk of injuring healthy areas of the brain, often resulting in permanent neurological deficits. In 1891, the prominent Italian neurologist Camillo Negro (1861-1927) described a new technique to treat focal epilepsy using galvanic electrical stimulation of the motor cortex to induce selective cortical destruction. The procedure of "cortical electrolysis", initially performed by prof. Antonio Carle (1854-1927), chief surgeon at the Mauriziano Hospital of Turin, aimed at avoiding the risk of hemorrhage and neurological deficits due to the resective surgical procedures, without compromising asepsis. Camillo Negro deserves to be credited as the first to have envisioned a non-resective surgical approach to the treatment of epilepsy, which in its conceptual basis appears nowadays as extraordinarily modern and pioneering. Recent neurosurgical procedures, such as stereoelectroencephalography-guided radiofrequency thermocoagulation and MRI-guided laser-induced interstitial thermal ablation, although based on different technologies, share the same rationale, using minimally invasive epilepsy surgery to reduce tissue disruption and thus morbidity.

Readability of online sources of information regarding epilepsy surgery and its impact on decision-making processes.

INTRODUCTION: People with epilepsy can have cognitive deficits, including difficulty with reading tasks. This can potentially impact on how written information is understood. Websites increasingly provide information about different medical interventions including epilepsy surgery. Our aim was to assess the readability of a sample of one hundred patient-oriented educational English language websites related to epilepsy surgery. METHODS: A Google search was carried out using the terms epilepsy and surgery, and a sample of forty-nine websites from both the UK and the US were chosen. These websites were uploaded to a freely available online readability scoring tool (readabilityformulas.com) and seven measures of readability generated were examined. Other data including use of figures/diagrams, patient narratives, and mention of the risks/benefits of surgery were noted. RESULTS: The majority of the websites analyzed in this study were found to be 'difficult' to read for the average reading level of the population (n = 1-impossible, 10-very difficult, 23-difficult, 14 fairly difficult). Only 1 website was considered suitable for average reading level. The use of infographics was variable - some webpages used them extensively to reiterate the textual information and other websites did not. DISCUSSION AND CONCLUSION: The available online patient information literature is likely to be too difficult for the average reader to understand. It is important that websites are accessible, reliable, and aid understanding related to epilepsy surgery, taking potential cognitive deficits into consideration.

Jean-Martin Charcot (1825-1893) and his second thoughts about hysteria / Jean-Martin Charcot (1825-1893) y sus dudas sobre la histeria

ABSTRACT Jean-Martin Charcot's (1825-1893) concepts of hysteria evolved significantly over the last 20 years of his career. In the "Leçons du Mardi à la Salpêtrière" (Tuesday lessons), his original conception of a "dynamic lesion" coexists alongside a new psychological conception, sometimes in a rather contradictory way. According to the hand-written transcript of his Tuesday lesson on February 21st, 1888, Charcot stated: "Hysteria must be taken for what it is: psychic disease par excellence". However, in the printed edition of the Tuesday lessons, this emphasis on psychological factors was very much softened. The different wording and corresponding shift in meaning implicitly retrieved Charcot's former conception of a "dynamic lesion". Charcot himself had probably been made aware of the different wording by the editors, and had agreed upon it. After several years of studying this condition, Charcot was probably not confident enough in making too assertive conclusions on the psychological mechanisms underlying hysteria.

RESUMEN Los conceptos de Jean-Martin Charcot (1825-1893) sobre la histeria evolucionaron significativamente durante los últimos 20 años de su carrera. En las "Leçons du Mardi à la Salpêtrière", su concepción original de una "lesión dinámica" coexiste junto con una nueva concepción psicológica, a veces de una manera bastante contradictoria. Según la transcripción manual de su lección del martes del 21 de febrero de 1888, Charcot declaró: "La histeria debe tomarse por lo que es: enfermedad psíquica por excelencia". Sin embargo, en la edición impresa de las lecciones del martes, este énfasis en los factores psicológicos se suavizó mucho. La diferente redacción y el cambio correspondiente en el significado recuperaron implícitamente la antigua concepción de Charcot de una "lesión dinámica". El proprio Charcot probablemente se había enterado de la diferente redacción por parte de los editores y lo había aceptado. Después de varios años estudiando esta afección, Charcot probablemente no estaba lo suficientemente seguro para sacar conclusiones demasiado asertivas sobre los mecanismos psicológicos subyacentes a la histeria.

Sonography of optic nerve sheath diameter identifies patients with middle cerebral artery infarction at risk of a malignant course: a pilot prospective observational study.

INTRODUCTION: To assess the value of optic nerve sheath diameter (ONSD) measurements at different time points to predict the malignant evolution in middle cerebral artery (MCA) infarction and to investigate the relationship between ONSD and infarct volume on follow-up computed tomography (CT). METHODS: In a single-center prospective observational study, we recruited patients with MCA infarction and age- and sex-matched controls. Clinical characteristics including NationaI Institutes of Health Stroke Scale (NIHSS) and ONSD measurement were assessed during the first five days after symptom onset. Volumetric analysis of the infarction was performed by a neuroradiologist, who was blinded to results of ONSD measurement and clinical examinations, based on  CT scans. RESULTS: We enrolled 29 patients with MCA infarction, including 10 with malignant MCA (mMCA) infarction and 14 controls. Mean ONSD on admission was already larger in patients who had developed an mMCA (5.99 ± 0.32 mm) compared to patients with MCA infarction (4.98 ± 0.53 mm; P = 0.003), and to control patients (4.57 ± 0.29 mm; P < 0.001). Correlation was observed between the ONSD mean value bilateral measures per individual and volumetric evaluation of cerebral infarction in the CT scan after one day (r = 0.623; P = 0.002). An ONSD value of 5.6 mm predicted an mMCA with a sensitivity of 100% and specificity of 90% yielding a positive predictive value of 83% and negative predictive value of 100%. CONCLUSIONS: ONSD measurement might be accurate for the noninvasive detection of increased ICP and for the recognition of patients being likely to develop mMCA.

Cerebral HSV-1 Vasculitis as a Fatal Complication of Immunosuppression in Non-Hodgkin´s Lymphoma: A Case Report and Review of the Literature.

Patients with lymphoma are predisposed to infection because of the immunocompromised state related to the disease itself and as a consequence of chemo-/radiotherapy. Here, we report a case of Herpes-simplex virus encephalitis (HSE) in an immunosuppressed patient with splenic marginal zone lymphoma (SMZL), a rare indolent variant of non-Hodgkin´s lymphoma (NHL). The course was complicated febrile neutropenia and HSV-1-related cerebral vasculitis causing progressive ischemic stroke. This case illustrates the expanding spectrum of atypical clinical and radiological manifestations of HSE in patients treated with myelotoxic drugs. Moreover, we summarize the few central nervous system manifestations of SMZL reported in the literature and discuss distinct causes of neurological deterioration in patients with NHL.

What can Google Trends and Wikipedia-Pageview analysis tell us about the landscape of epilepsy surgery over time?

BACKGROUND: Epilepsy surgery is an effective treatment for drug-resistant epilepsy. Some centers have noticed changes in referral patterns. AIM: The aim of this study was to determine if online infodemiological data related to epilepsy surgery reflect reported changes in referrals to surgical centers. METHODS: Google Trends and Pageview analysis of temporal trends of searches conducted in Google and Wikipedia for epilepsy surgery, using key search terms such as "epilepsy surgery" and terms related to pathology, operation type, and investigative practice. RESULTS: Over the 15-year time period studied by Google trend analysis, when the initial three-year epoch and final three-year epoch are compared, a 56.1% decline in search volume for "epilepsy surgery" was observed. Vagus nerve stimulation and laser ablation are increasingly searched items. Pageview analysis shows that temporal lobe epilepsy remains the most commonly searched subtype of epilepsy and hippocampal sclerosis was searched for more than focal cortical dysplasia. CONCLUSION: This study suggests a lower search interest over time in epilepsy surgery, and various associated terms, with increased interest in vagus nerve stimulation and laser ablation procedures over time. There is no clear indication from these data regarding the apparent shift from mesial temporal cases to an increase in extratemporal case workload.

Epidemiology of paraneoplastic neurological syndromes: a population-based study.

BACKGROUND: The epidemiology of paraneoplastic neurological syndromes (PNS) remains to be defined. We present here the first population-based incidence study and report the clinical spectrum and antibody profile of PNS in a large area in Northeastern Italy. METHODS: We performed a 9-year (2009-2017) population-based epidemiological study of PNS in the provinces of Udine, Pordenone and Gorizia, in the Friuli-Venezia Giulia region (983,190 people as of January 1, 2017). PNS diagnosis and subgroups were defined by the 2004 diagnostic criteria. Age- and sex-adjusted incidence rates were calculated. RESULTS: We identified 89 patients with a diagnosis of definite PNS. Median age was 68 years (range 26-90), 52% were female. The incidence of PNS was 0.89/100,000 person-years. PNS incidence rates increased over time from 0.62/100,000 person-years (2009-2011), 0.81/100,000 person-years (2012-2014) to 1.22/100,000 person-years (2015-2017). The prevalence of PNS was 4.37 per 100,000. Most common PNS were limbic encephalitis (31%), cerebellar degeneration (28%) and encephalomyelitis (20%). Among antibody (Ab)-positive cases, most frequent specificities included: Yo (30%), Hu (26%), and Ma2 (22%), while the most frequent associated tumors were lung (17%) and breast cancer (16%), followed by lymphoma (12%). PNS developed in 1 in every 334 cancers in our region. Statistically significant associations were observed between cancer type and Ab-specificity (P < 0.001), and between neurological syndrome and Ab-specificity (P < 0.001). CONCLUSIONS: This first population-based study found an incidence of PNS that approximates 1/100,000 person-years and a prevalence of 4/100,000. Moreover, the incidence of PNS is increasing over time, probably due to increased awareness and improved detection techniques.

Effects of repetitive transcranial magnetic stimulation on nicotine consumption and craving: A systematic review.

We performed a systematic review of the studies employing repetitive transcranial magnetic stimulation (rTMS) in subjects with smoking addiction. High-frequency (HF) rTMS over the prefrontal cortex (PFC), in particular the left dorsolateral PFC (DLPFC), might represent a save and innovative treatment tool for tobacco consumption and craving in nicotine-dependent otherwise healthy people. rTMS can be effective for this indication also in patients with schizophrenia, but the results are conflicting and sufficient evidence from large-scale trials is still lacking. Promising results have been obtained using particular techniques for brain stimulation, such as deep rTMS and theta burst stimulation. Multiple-target HF rTMS can also have a potential in smoking cessation. fMRI and EEG recordings have proven to be useful for objectively assessing the treatment effects. TMS is likely to be most effective when paired with an evidence-based self-help intervention, cognitive-behavioral interventions and nicotine replacement therapy. However, the most recent studies employed different protocols and yielded heterogeneous results, which should be replicated in further controlled studies with larger sample sizes and rigorous standards of randomization. To date, no recommendation other than that a possible efficacy of HF-rTMS of the left DLPFC can be made for alternative rTMS procedures in nicotine craving and consumption.

Cholinergic transmission is impaired in patients with idiopathic normal-pressure hydrocephalus: a TMS study.

The pathophysiological mechanisms of cognitive and gait disturbances in subjects with normal-pressure hydrocephalus (NPH) are still unclear. Cholinergic and other neurotransmitter abnormalities have been reported in animal models of NPH. The objective of this study was to evaluate the short latency afferent inhibition (SAI), a transcranial magnetic stimulation protocol which gives the possibility to test an inhibitory cholinergic circuit in the human brain, in subjects with idiopathic NPH (iNPH). We applied SAI technique in twenty iNPH patients before ventricular shunt surgery. Besides SAI, also the resting motor threshold and the short intracortical inhibition to paired stimulation were assessed. A significant reduction of the SAI (p = 0.016), associated with a less pronounced decrease of the resting motor threshold and the short latency intracortical inhibition to paired stimulation, were observed in patients with iNPH at baseline evaluation. We also found significant (p < 0.001) correlations between SAI values and the gait function tests, as well as between SAI and the neuropsychological tests. These findings suggest that the impairment of cholinergic neurons markedly contributes to cognitive decline and gait impairment in subjects with iNPH.