Hindbrain Double-Negative Feedback Mediates Palatability-Guided Food and Water Consumption.

Hunger and thirst have distinct goals but control similar ingestive behaviors, and little is known about neural processes that are shared between these behavioral states. We identify glutamatergic neurons in the peri-locus coeruleus (periLCVGLUT2 neurons) as a polysynaptic convergence node from separate energy-sensitive and hydration-sensitive cell populations. We develop methods for stable hindbrain calcium imaging in free-moving mice, which show that periLCVGLUT2 neurons are tuned to ingestive behaviors and respond similarly to food or water consumption. PeriLCVGLUT2 neurons are scalably inhibited by palatability and homeostatic need during consumption. Inhibition of periLCVGLUT2 neurons is rewarding and increases consumption by enhancing palatability and prolonging ingestion duration. These properties comprise a double-negative feedback relationship that sustains food or water consumption without affecting food- or water-seeking. PeriLCVGLUT2 neurons are a hub between hunger and thirst that specifically controls motivation for food and water ingestion, which is a factor that contributes to hedonic overeating and obesity.

Early second-trimester three-dimensional transvaginal neurosonography of fetal midbrain and hindbrain: normative data and technical aspects.

OBJECTIVES: To provide a detailed description of the sonographic appearance and development of various fetal structures of the midbrain and hindbrain (MBHB) during the early second trimester, and to evaluate the impact of the frequency of the transvaginal sonography (TVS) transducer on the early recognition of these structures. METHODS: This was a retrospective analysis of three-dimensional volumetric datasets of the MBHB from apparently normal fetuses at 14-19 gestational weeks, acquired by TVS in the midsagittal view through the posterior fontanelle. Using a multiplanar approach, we measured the tectal thickness and length, aqueductal thickness, tegmental thickness and width and height of the Blake's pouch (BP) neck. In addition, we assessed the existence of early vermian fissures, the linear shape of the brainstem and the components of the fastigium. The correlation between gestational age according to last menstrual period and sonographic measurements of MBHB structures was evaluated using Pearson's correlation (r). A subanalysis was performed to assess the performance of a 5-9-MHz vs a 6-12-MHz TVS transducer in visualizing the MBHB structures in the early second trimester. RESULTS: Sixty brain volumes were included in the study, obtained at a mean gestational age of 16.2 weeks (range, 14.1-19.0 weeks), with a transverse cerebellar diameter range of 13.0-19.8 mm. We found a strong correlation between gestational age and all MBHB measurements, with the exception of the tectal, tegmental and aqueductal thicknesses, for which the correlation was moderate. There was good-to-excellent intraobserver and moderate-to-good interobserver correlation for most MBHB measurements. We observed that the BP neck was patent in all fetuses between 14 and 18 weeks with decreasing diameter, and that the aqueductal thickness was significantly smaller at ≥ 18 weeks compared with at < 16 weeks. The early vermian fissures and the linear shape of the brainstem were present in all fetuses from 14 weeks. We found that, in the early second trimester, the horizontal arm of the presumed 'fastigium' evolves from the fourth ventricular choroid plexus and not the posterior vermis, indicating that this is not the fastigium. Standard- and high-resolution TVS transducers performed similarly in the assessment of MBHB anatomy. CONCLUSION: Detailed early second-trimester assessment of the MBHB is feasible by transvaginal neurosonography and provides reference data which may help in the early detection of brain pathology involving the MBHB. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Clinical and molecular evaluation of 13 Brazilian patients with Gomez-López-Hernández syndrome.

We aim to characterize patients with Gomez-López-Hernández syndrome (GLHS) clinically and to investigate them molecularly. A clinical protocol, including a morphological and neuropsychological assessment, was applied to 13 patients with GLHS. Single-nucleotide polymorphism (SNP) array and whole-exome sequencing were undertaken; magnetic resonance imaging was performed in 12 patients, including high-resolution, heavily T2-weighted sequences (HRT2) in 6 patients to analyze the trigeminal nerves. All patients presented alopecia; two did not present rhombencephalosynapsis (RES); trigeminal anesthesia was present in 5 of the 11 patients (45.4%); brachycephaly/brachyturricephaly and mid-face retrusion were found in 84.6 and 92.3% of the patients, respectively. One patient had intellectual disability. HRT2 sequences showed trigeminal nerve hypoplasia in four of the six patients; all four had clinical signs of trigeminal anesthesia. No common candidate gene was found to explain GLHS phenotype. RES does not seem to be an obligatory finding in respect of GLHS diagnosis. We propose that a diagnosis of GLHS should be considered in patients with at least two of the following criteria: focal non-scarring alopecia, rhombencephalosynapsis, craniofacial anomalies (brachyturrycephaly, brachycephaly or mid-face retrusion), trigeminal anesthesia or anatomic abnormalities of the trigeminal nerve. Studies focusing on germline whole genome sequencing or DNA and/or RNA sequencing of the alopecia tissue may be the next step for the better understanding of GLHS etiology.

Prenatal diagnosis of rhombencephalosynapsis: neuroimaging features and severity of vermian anomaly.

OBJECTIVES: To describe the prenatal neuroimaging spectrum of rhombencephalosynapsis (RES) and criteria for its classification according to the severity of vermian anomaly. METHODS: In this multicenter retrospective study of fetuses with RES between 2002 and 2020, the medical records and brain ultrasound and magnetic resonance images were evaluated comprehensively to determine the severity of the vermian anomaly and the presence of associated brain findings. RES was classified, according to the pattern of vermian agenesis and the extent of the fusion of the hemispheres, as complete RES (complete absence of the vermis) or partial RES (further classified according to the part of the vermis that was missing and, consequently, the region of hemispheric fusion, as anterior, posterior, severe or mixed RES). Findings were compared between cases with complete and those with partial RES. RESULTS: Included in the study were 62 fetuses with a gestational age ranging between 12 and 37 weeks. Most had complete absence of the vermis (complete RES, 77.4% of cases), a 'round-shaped' cerebellum on axial views (72.6%) and a transverse cerebellar diameter (TCD) < 3rd centile (87.1%). Among the 22.6% of cases with partial RES, 6.5% were classified as severe partial, 6.5% as partial anterior, 8.1% as partial mixed and 1.6% as partial posterior. Half of these cases presented with normal or nearly normal cerebellar morphology and 28.5% had a TCD within the normal limits. Infratentorially, the fourth ventricle was abnormal in 88.7% of cases overall, and anomalies of the midbrain and pons were frequent (93.5% and 77.4%, respectively). Ventriculomegaly was observed in 80.6% of all cases, being more severe in cases with complete RES than in those with partial RES, with high rates of parenchymal and septal disruption. CONCLUSIONS: This study provides prenatal neuroimaging criteria for the diagnosis and classification of RES, and identification of related features, using ultrasound and magnetic resonance imaging. According to our findings, a diagnosis of RES should be considered in fetuses with a small TCD (severe cerebellar hypoplasia) and/or a round-shaped cerebellum on axial views, during the second or third trimester, especially when associated with ventriculomegaly. Partial RES is more common than previously thought, but presents an extreme diagnostic challenge, especially in cases with normal or nearly-normal cerebellar morphobiometric features. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Hindbrain Herniation and Banana and Lemon Sign After Open Fetal Myelomeningocele Repair - When Do These Signs Disappear and is Shunting Predictable?

PURPOSE: The aim was to describe the sonographic follow-up of hindbrain herniation (HH), the banana and lemon sign after fetal myelomeningocele (fMMC) repair, and the time of disappearance of these signs after the intervention, and to investigate any predictive value for the necessity of shunting during the infant's first year of life. Additionally, the sonographic evolution of the transcerebellar diameter (TCD) before and after fetal intervention was assessed. PATIENTS AND METHODS: The first 50 patients that underwent fMMC repair at Zurich Center for Fetal Diagnosis and Therapy (www.swissfetus.ch) were included in this study. Sonographic scans performed weekly after fMMC repair focusing on HH and banana and lemon signs were analyzed and compared between the shunted and the non-shunted group. ROC curves were generated for the time intervals of resolution of the signs in order to show their predictive accuracy for the need for shunting until 1 year of age. RESULTS: HH resolved in 48 fetuses (96 %) before delivery. The sonographic disappearance of HH within the first two weeks after fMMC repair was associated with a significantly lower incidence of shunt placement (OR 0.19; 95 % CI 0.4-0.9) during the first year of life (p = 0.03). All fetuses with persistent HH before delivery received a shunt. TCD growth was observed in all fetuses. CONCLUSION: The reversibility of HH within two weeks after fMMC repair is associated with an 80 % lower incidence of shunt placement during the infant's first year of life. Moreover, it allows the cerebellum to grow and to normalize its configuration.

Listeria rhombencephalitis mimicking acute disseminated encephalomyelitis in a patient without predisposing medical conditions.

Listeria rhombencephalitis (L. rhombencephalitis) is an uncommon form of central nervous system infection caused by Listeria monocytogenes (LM). It often occurs to immunocompetent individuals. Here, we described the case of a 45-year-old female patient without medical histories, who presented for high-grade fever, headache, and focal neurological manifestations. She was initially empirically diagnosed with acute disseminated encephalomyelitis (ADEM) because of clinical symptoms, acute clinical course, and neuroimaging. However, the biochemical analysis of cerebral spinal fluid (CSF) questioned the diagnosis of ADEM. The final diagnosis of L. rhombencephalitis was based on CSF culture for LM. Thus, L. rhombencephalitis should be preferentially and empirically considered for a patient with significantly elevated lactic acid and moderately increased red cells in CSF at early time, accompanied with rapidly progressive neurological dysfunctions involved in the brain stem.

Gomez-López-Hernández syndrome: A case report with clinical and molecular evaluation and literature review.

Gomez-López-Hernández syndrome (GLHS) is characterized by rhombencephalosynapsis (RES), alopecia, trigeminal anesthesia and a distinctive phenotype, including brachyturricephaly. It has been suggested that GLHS should be considered as part of the spectrum of RES-associated conditions that include alopecia, trigeminal anesthesia, and craniofacial anomalies, rather than a distinct entity. To the best of our knowledge, 57 patients with GLHS have been described. Despite its first description in 1979, the etiology of this syndrome remains unknown. Here, we describe, to our knowledge, the first case of a patient with GLHS who was molecularly evaluated and had been prenatally exposed to misoprostol. We also reviewed the clinical and morphological features of the patients described to date to better delineate the phenotype and focus on any evidence for adverse pregnancy outcomes or exposure, including teratogens.

Homozygous ARHGEF2 mutation causes intellectual disability and midbrain-hindbrain malformation.

Mid-hindbrain malformations can occur during embryogenesis through a disturbance of transient and localized gene expression patterns within these distinct brain structures. Rho guanine nucleotide exchange factor (ARHGEF) family members are key for controlling the spatiotemporal activation of Rho GTPase, to modulate cytoskeleton dynamics, cell division, and cell migration. We identified, by means of whole exome sequencing, a homozygous frameshift mutation in the ARHGEF2 as a cause of intellectual disability, a midbrain-hindbrain malformation, and mild microcephaly in a consanguineous pedigree of Kurdish-Turkish descent. We show that loss of ARHGEF2 perturbs progenitor cell differentiation and that this is associated with a shift of mitotic spindle plane orientation, putatively favoring more symmetric divisions. The ARHGEF2 mutation leads to reduction in the activation of the RhoA/ROCK/MLC pathway crucial for cell migration. We demonstrate that the human brain malformation is recapitulated in Arhgef2 mutant mice and identify an aberrant migration of distinct components of the precerebellar system as a pathomechanism underlying the midbrain-hindbrain phenotype. Our results highlight the crucial function of ARHGEF2 in human brain development and identify a mutation in ARHGEF2 as novel cause of a neurodevelopmental disorder.

Fourth ventricle index: sonographic marker for severe fetal vermian dysgenesis/agenesis.

OBJECTIVE: Prenatal diagnosis of midbrain-hindbrain (MB-HB) malformations relies primarily on abnormal size and shape of the cerebellum and retrocerebellar space, particularly 'open fourth ventricle' (4V), the most common indicator of MB-HB malformations. The aim of this study was to present the fourth ventricle index (4VI), and to evaluate its role as a marker for severe vermian dysgenesis/agenesis in cases without open 4V. METHODS: This was a prospective cross-sectional study of patients with singleton low-risk pregnancy at 14 + 1 to 36 + 6 gestational weeks presenting between May 2016 and November 2017 for routine ultrasound examination. Axial images of the fetal 4V were obtained and the 4VI was calculated as the ratio between the laterolateral and the anteroposterior diameters. Reference ranges were constructed and retrospectively collected values from 44 fetuses with confirmed anomalies involving severe vermian dysgenesis/agenesis (Joubert syndrome and related disorders, rhombencephalosynapsis, cobblestone malformations and cerebellar hypoplasia) but without open 4V were compared with the normal values. RESULTS: In total, 384 healthy fetuses were enrolled into the study, from which reference ranges were produced, and 44 cases were collected retrospectively. The 4VI in the normal fetuses was always > 1. In affected fetuses, it was always below mean -2 SD and < 1. CONCLUSIONS: The 4VI is a sonographic marker for severe fetal vermian dysgenesis/agenesis in the absence of an open 4V. It may be incorporated easily into the routine brain scan; 4VI < 1 indicates a need for dedicated fetal neuroimaging for diagnosis and prenatal counseling. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Defining, diagnosing, clarifying, and classifying the Chiari I malformations.

PURPOSE: Chiari malformations (CM) have been traditionally classified into four categories: I, II, III, and IV. In light of more recent understandings, variations of the CM have required a modification of this classification. METHODS: This article discusses the presentation, diagnostics, and treatment of the newer forms of hindbrain herniation associated with the CM type I. RESULTS: The CM 1 is a spectrum that includes some patients who do not fall into the exact category of this entity. CONCLUSIONS: While CM have been categorically recognized as discrete and individual conditions, newer classifications such as CM 0 and CM 1.5 exhibit some degree of continuity with CM 1; however, they require distinct and separate classification as symptoms and treatments can vary among these clinical subtypes.

Enhancing nodular lesions in Chiari II malformations in the setting of persistent hindbrain herniation: case report and literature review.

BACKGROUND: Chiari II malformation includes concomitant cerebellar tonsillar herniation, hydrocephalus, and myelomeningocele. Rarely, pediatric patients with persistent hindbrain herniation develop a new enhancing nodule at the cervicomedullary junction as adults. These new lesions may be suspicious for neoplastic growth, but it remains unclear if neurosurgical intervention is necessary. CASE REPORT: A 27-year-old female patient with history of Chiari II malformation and persistent hindbrain herniation presented with a 3-month history of headache and upper extremity weakness and numbness. Neuroimaging revealed a new enhancing nodule near the cervicomedullary junction suspicious for neoplasm. Following posterior fossa decompression and excision of the enhancing lesion, pathological analysis demonstrated only benign glioneural heterotopia. RESULTS: New enhancing nodules at the cervicomedullary junction in Chiari II malformation are exceedingly rare and are likely benign, reactive changes rather than a neoplastic process. Biopsy or surgical excision of these lesions is likely unnecessary for asymptomatic patients.

A morphometric assessment of type I Chiari malformation above the McRae line: A retrospective case-control study in 302 adult female subjects.

PURPOSE: Type I Chiari malformation (CMI) is a radiologically-defined structural dysmorphism of the hindbrain and posterior cranial fossa (PCF). Traditional radiographic identification of CMI relies on the measurement of the cerebellar tonsils in relation to the foramen magnum with or without associated abnormalities of the neuraxis. The primary goal of this retrospective study was to comprehensively assess morphometric parameters above the McRea line in a group of female CMI patients and normal controls. MATERIAL AND METHODS: Twenty-nine morphological measurements were taken on 302 mid-sagittal MR images of adult female CMI patients (n=162) and healthy controls (n=140). All MR images were voluntarily provided by CMI subjects through an online database and control participant images were obtained through the Human Connectome Project and a local hospital system. RESULTS: Analyses were performed on the full dataset of adult female MR images and a restricted dataset of 229 participants that were equated for age, race, and body mass index. Eighteen group differences were identified in the PCF area that we grouped into three clusters; PCF structures heights, clivus angulation, and odontoid process irregularity. Fourteen group differences persisted after equating our CMI and control groups on demographic characteristics. CONCLUSION: PCF structures reliably differ in adult female CMI patients relative to healthy controls. These differences reflect structural abnormalities in the osseous and soft tissue structures of the clivus, odontoid process, and cerebellum. Clinical and pathophysiological implications are discussed.

A Rare Case of Basioccipital Encephalomeningocele with Tethered Dermoid Presenting as Cranial Nerve Palsy: A Case Report.

The basioccipital skull base is an extremely rare site for meningoencephalocele. The herniation of the brainstem or part of it through a basioccipital defect is even rarer. We report a case of rhombencephalomeningocele associated with a tethered dermoid. An extensive literature search revealed no such case report of basioccipital cranial dysraphism so far presenting with cranial nerve palsy.

Assessment of fetal midbrain and hindbrain in mid-sagittal cranial plane by three-dimensional multiplanar sonography. Part 1: comparison of new and established nomograms.

OBJECTIVE: To construct nomograms for fetal midbrain (MB) and hindbrain (HB) dimensions, assessed in the mid-sagittal cranial plane by three-dimensional multiplanar sonographic reconstruction (3D-MPR). METHODS: This was a prospective cross-sectional study of 334 healthy fetuses in low-risk singleton pregnancies between 16 and 35 gestational weeks. All sonographic volumes were obtained by sagittal acquisition. The following MB and HB parameters were evaluated in the mid-sagittal cranial plane using 3D-MPR: MB parameters tectal length (TL) and anteroposterior midbrain diameter (APMD), and HB parameters anteroposterior pons diameter (APPD), superoinferior vermian diameter (SIVD), anteroposterior vermian diameter (APVD) and anteroposterior diameter of the fourth ventricle (APDFV). The measurements were presented as growth charts according to gestational age. RESULTS: MB and HB biometry were best assessed between 19 and 29 weeks. During this period, adequate visualization was achieved for successful measurement of TL in 90.9% of cases, APMD in 86.6%, APPD in 73.7%, SIVD in 74.2%, APVD in 71% and APDFV in 71%. There was a linear growth pattern, with Pearson correlation coefficients of 0.79 for TL, 0.88 for APMD, 0.91 for APPD, 0.95 for SIVD, 0.88 for APVD and 0.88 for APDFV (P < 0.0001 for each). The mean intra- and interobserver variations for the MB measurements and vermian diameters ranged between 4.3% and 9%. APPD and APDFV showed highest mean variations: 9.0% and 19.4% (intraobserver) and 11.6% and 17.7% (interobserver), respectively. CONCLUSION: We present new nomograms for assessment of the fetal MB and HB using 3D-MPR in the mid-sagittal cranial plane. To our knowledge, these are the first proposed nomograms for fetal MB dimensions.

Assessment of fetal midbrain and hindbrain in mid-sagittal cranial plane by three-dimensional multiplanar sonography. Part 2: application of nomograms to fetuses with posterior fossa malformations.

OBJECTIVES: To apply fetal midbrain (MB) and hindbrain (HB) nomograms, developed using three-dimensional multiplanar sonographic reconstruction (3D-MPR) in the mid-sagittal cranial plane, to fetuses with known posterior fossa malformations. METHODS: In this retrospective study we examined sonographic volumes obtained by sagittal acquisition in 43 fetuses diagnosed with posterior fossa abnormalities and evaluated in the mid-sagittal cranial plane, using 3D-MPR, the following: MB parameters tectal length (TL) and anteroposterior midbrain diameter (APMD), and HB parameters anteroposterior pons diameter (APPD), superoinferior vermian diameter (SIVD) and anteroposterior vermian diameter (APVD). Fetuses were grouped, according to malformation, into eight categories: cobblestone malformation complex (CMC, n = 3), Chiari-II malformation (C-II, n = 7), pontocerebellar hypoplasia (PCH, n = 2), rhombencephalosynapsis (RES, n = 4), Dandy-Walker malformation (n = 8), vermian dysgenesis (VD, n = 7), persistent Blake's pouch cyst (n = 6) and megacisterna magna (n = 6). In each case and for each subgroup, the MB-HB biometric parameters and their z-scores were evaluated with reference to our new nomograms. RESULTS: The new MB-HB nomograms were able to identify the brainstem and vermian anomalies and differentiate fetuses with MB-HB malformations from those with isolated enlarged posterior fossa cerebrospinal fluid spaces. Use of the nomograms enabled detection of an elongated tectum in fetuses with CMC, C-II and RES, and a flattened pontine belly in cases of CMC, PCH and VD. In the fetuses with VD, the nomograms enabled division into three distinctive groups: (1) those with small SIVD and APVD, (2) those with normal SIVD but small APVD, and (3) those with small SIVD but normal APVD. CONCLUSIONS: Application of our new reference data, that for the first time include the MB, enables accurate diagnosis of brain malformations affecting the MB and HB and makes possible novel characterization of previously described features of posterior fossa anomalies.

ChOP-CT: quantitative morphometrical analysis of the Hindbrain Choroid Plexus by X-ray micro-computed tomography.

The Hindbrain Choroid Plexus is a complex, cerebrospinal fluid-secreting tissue that projects into the 4th vertebrate brain ventricle. Despite its irreplaceability in the development and homeostasis of the entire central nervous system, the research of Hindbrain Choroid Plexus and other Choroid Plexuses has been neglected by neuroscientists for decades. One of the obstacles is the lack of tools that describe the complex shape of the Hindbrain Choroid Plexus in the context of brain ventricles. Here we introduce an effective tool, termed ChOP-CT, for the noninvasive, X-ray micro-computed tomography-based, three-dimensional visualization and subsequent quantitative spatial morphological analysis of developing mouse Hindbrain Choroid Plexus. ChOP-CT can reliably quantify Hindbrain Choroid Plexus volume, surface area, length, outgrowth angle, the proportion of the ventricular space occupied, asymmetries and general shape alterations in mouse embryos from embryonic day 13.5 onwards. We provide evidence that ChOP-CT is suitable for the unbiased evaluation and detection of the Hindbrain Choroid Plexus alterations within various mutant embryos. We believe, that thanks to its versatility, quantitative nature and the possibility of automation, ChOP-CT will facilitate the analysis of the Hindbrain Choroid Plexus in the mouse models. This will ultimately accelerate the screening of the candidate genes and mechanisms involved in the onset of various Hindbrain Choroid Plexus-related diseases.

Catastrophic Case of West Nile Virus Rhombencephalitis in AIDS.

West Nile Virus (WNV) belongs to the Flaviviridae family of viruses. It was first isolated and identified in 1937. Patients typically present with flu-like symptoms or are asymptomatic; however, neuroinvasive West Nile can lead to significant neurological impairment. Herein presented is a catastrophic case of WNV rhombencephalitis in a male patient newly diagnosed with AIDS. This report sheds light on the potential for severe neurological complications in co-infected patients and emphasizes the importance of early recognition.

Epidemiology, clinical and imaging features of rhombencephalitis caused by L. monocytogenes. A retrospective observational study. / Epidemiología, clínica y resultados de imagen de rombencefalitis causada por L. monocytogenes. Un estudio observacional.

INTRODUCTION: To date, few studies have explored the specific risk factors of patients with listeriosis who develop rhombencephalitis, and there is insufficient information regarding imaging findings and clinical symptoms in patients with this disease. This work aimed to analyze the imaging findings associated with L. monocytogenes rhombencephalitis in a cohort of patients with listeriosis. MATERIALS AND METHODS: We conducted a retrospective observational study of all declared cases of listeriosis in a tertiary hospital from Granada, Spain, from 2008 to 2021. Risk factors, comorbidities, and clinical outcomes were collected for all patients. In addition, clinical symptoms and magnetic resonance imaging (MRI) findings were included for those patients who developed rhombencephalitis. Descriptive and bivariate analyses were performed using SPSS statistical software (IBM SPSS, version 21). RESULTS: Our cohort comprised 120 patients with listeriosis (41.7% women, mean age: 58.6 ± 23.8 years), of which 10 (8.3%) had rhombencephalitis. The most frequent MRI findings in patients with confirmed rhombencephalitis were T2-FLAIR hyperintensity (100%), T1 hypointensity (80%), scattered parenchymal enhancement (80%), and cranial nerve enhancement (70%), while the most frequent anatomical involvement were pons, medulla oblongata, and cerebellum. Complications occurred in 6 patients (abscess in 4, hemorrhage in 2, hydrocephalus in 1). CONCLUSIONS: Rhombencephalitis is associated with an increased in-hospital mortality in patients with listeriosis. The anatomical distribution and imaging characteristics of neurolisteriosis could be useful to suggest the diagnosis. Future studies with greater sample size should explore the association between anatomical location, imaging patterns, and associated complications (e.g., hydrocephalus, hemorrhage), and clinical outcomes.

TITLE: Epidemiología, clínica y resultados de imagen de rombencefalitis causada por L. monocytogenes. Un estudio observacional.Introducción. Hasta la fecha, pocos estudios han explorado los factores de riesgo específicos de los pacientes con listeriosis que desarrollan rombencefalitis, y no hay suficiente información sobre los hallazgos de imagen y los síntomas clínicos en pacientes con esta enfermedad. El objetivo de este trabajo fue analizar los hallazgos de imagen asociados a la rombencefalitis por L. monocytogenes en una cohorte de pacientes con listeriosis. Materiales y métodos. Se realizó un estudio observacional retrospectivo de todos los casos declarados de listeriosis en un hospital terciario de Granada, España, desde 2008 hasta 2021. Se recogieron los factores de riesgo, las comorbilidades y los resultados clínicos de todos los pacientes. Además, se incluyeron los síntomas clínicos y los hallazgos de resonancia magnética (RM) de los pacientes que desarrollaron rombencefalitis. Se realizaron análisis descriptivos y bivariados utilizando el software estadístico SPSS (IBM SPSS, versión 21). Resultados. Nuestra cohorte incluyó a 120 pacientes con listeriosis (41,7%, mujeres; edad media: 58,6 ± 23,8 años), de los cuales 10 (8,3%) tenían rombencefalitis. Los hallazgos más frecuentes en la RM de los pacientes con rombencefalitis confirmada fueron hiperintensidad en T2-FLAIR (100%), hipointensidad en T1 (80%), realce parenquimatoso disperso (80%) y realce de los nervios craneales (70%), mientras que la afectación anatómica más frecuente fue en la protuberancia, la médula oblongada y el cerebelo. Se produjeron complicaciones en seis pacientes (absceso en cuatro, hemorragia en dos e hidrocefalia en uno). Conclusiones. La rombencefalitis se asocia a un aumento de la mortalidad intrahospitalaria en pacientes con listeriosis. La distribución anatómica y las características de imagen de la neurolisteriosis podrían ser útiles para sugerir el diagnóstico. Futuros estudios con mayor tamaño muestral deberían explorar la asociación entre la localización anatómica, los patrones de imagen y las complicaciones asociadas (por ejemplo, hidrocefalia y hemorragia), y los resultados clínicos.