Prevalencia del desarrollo de entesofito en la Protuberancia Occipital Externa en población de paraguayos / Prevalence of enthesophyte development in External Occipital Protuberance in Paraguayan population

Introducción.La Protuberancia Occipital Externa (POE) es una superficie convexa y lisa que tradicionalmente no presenta ningún tipo de irregularidades. La aparición de un entesofito en individuos ha llamado la atención de los investigadores. Objetivo.Determinar la prevalencia, longitud, edad y sexo de una exostosis en forma de gancho desarrollada a nivel de la POE. Metodología.Estudio observacional descriptivo realizado en radiografías laterales de cráneo de individuos jóvenes. De 5065 radiografías, 4017 radiografías cumplieron con los criterios. Se procedió a la detección de la presencia de un gancho óseo en la POE y su medición. Resultados.Se incluyeron personas de ambos sexos entre 13 a 45 años: 2902 mujeres y 1115 varones. De las 4017 radiografías observadas, el 67% presentó la excrecencia en la POE, con rangos desde 5 a 24 mm en longitud, 511 tenían una longitud de 5 mm o mayor, 903 entre 9 a 12 mm de longitud y 253 de 13 a 24mm. Se observó enmayor proporción en el sexo masculino que el femenino(68% vs 32%). En los individuos de 40 años y más, solo un paciente de sexo masculino mostró la presencia del entesofito. Conclusión.Se ha encontrado una alta frecuencia del desarrollo de una protuberancia ósea a nivel del POE en jóvenes y adultos jóvenesde sexo masculino. Este es el primer estudio de este tipo realizado en la población del Paraguay. Para comprender la razón del desarrollo de esta excrecencia ósea, es necesario ampliar el área de investigación. Palabras Clave:ganchos óseos;protuberancia; exostosis; entesopatía.

Introduction.The external occipital protuberance (EOP) is a smooth convex surface which commonly does not present any type of irregularities. The development of an enthesophyte in young population has attracted the attention of researchers. Objective.To determine the prevalence, size, age, and sex of individuals with bony projections that resembles a hook developed in EOP. Methodology.Descriptive observational study. 5065 lateral skull x-rays were observed. 4017 fulfilled all the criteria. The x-rays were reviewed for the presence of a bony excrescence in EOP, and they were measured. Results. From a both sexes population between 13 to 45 years old 2902 were female and 1115 were male. 67% X-rays presented the enthesophyte ranging from 5 ­24mm in length. 511 out of 1667 had an enthesophyte at or above 5 mm. There were 903 patients with an enthesophyte ranging from 9 ­12 mm in length and 254 had the protuberance ranging from 13 ­24 mm. Statistically significant range of 68% vs 32% between males and females were observed. From individuals of 40 years and above, just 1 male patient out of 32 showedthe enthesophyte. Conclusion.Significant association with the development of a bony protuberance at the POE in young and young adult male population has been found. This is the first study of this type in Paraguayan individuals. To expand the field of studies, future research is needed to better examine and understand the reason forthe development of this bony excrescence. Key words:bone hooks; protuberance;exostoses; enthesopathies.

Magnetic resonance imaging features of cerebellar atrophy pattern after epilepsy / 中南大学学报(医学版)

OBJECTIVES@#Clinically, it has been found that some patients with epilepsy are accompanied by cerebellar atrophy that is inconsistent with symptoms, but the pattern of cerebellar atrophy after epilepsy and the role of cerebellar atrophy in the mechanism of epilepsy have not been elucidated. This study aims to explore the specific pattern of cerebellar atrophy after epilepsy via analyzing magnetic resonance images in patients with postepileptic cerebellar atrophy.@*METHODS@#A total of 41 patients with epilepsy, who received the treatment in Xiangya Hospital of Central South University from January 2017 to January 2022 and underwent cranial MRI examination, were selected as the case group. The results of cranial MRI examination of all patients showed cerebellar atrophy. In the same period, 41 cases of physical examination were selected as the control group. General clinical data and cranial MRI results of the 2 groups were collected. The maximum area and signal of dentate nucleus, the maximum width of the brachium pontis, the maximum anterior-posterior diameter of the pontine, and the maximum transverse area of the fourth ventricle were compared between the 2 groups. The indexes with difference were further subjected to logistic regression analysis to clarify the characteristic imaging changes in patients with cerebellar atrophy after epilepsy.@*RESULTS@#Compared with the control group, the maximum width of the brachium pontis and the maximum anterior-posterior diameter of the pontine were decreased significantly, the maximum transverse area of the fourth ventricle was increased significantly in the case group (all P<0.05). The difference in distribution of the low, equal, and high signal in dentate nucleus between the 2 groups was statistically significant (χ2=43.114, P<0.001), and the difference in the maximum area of dentate nucleus between the 2 groups was not significant (P>0.05). The maximum width of the brachium pontis [odds ratio (OR)=3.327, 95% CI 1.454 to 7.615, P=0.004] and the maximum transverse area of the fourth ventricle (OR=0.987, 95% CI 0.979 to 0.995, P=0.002) were independent factors that distinguished cerebellar atrophy after epilepsy from the normal control, while the anterior-posterior diameter of pontine (OR=1.456, 95% CI 0.906 to 2.339, P>0.05) was not an independent factor that distinguished them.@*CONCLUSIONS@#In MRI imaging, cerebellar atrophy after epilepsy is manifested as significant atrophy of the brachium pontis, significant enlargement of the fourth ventricle, and increased dentate nucleus signaling while insignificant dentate nucleus atrophy. This particular pattern may be associated with seizures and exacerbated pathological processes.

Transaxonal degenerations of cerebellar connections: the value of anatomical knowledge / Degenerações transaxonais das conexões cerebelares: o valor do conhecimento anatômico

ABSTRACT Transaxonal degenerations result from neuronal death or the interruption of synaptic connections among neuronal structures. These degenerations are not common but may be recognized by conventional magnetic resonance imaging. Objective: The learning objectives of this review include recognition of the imaging characteristics of transaxonal degenerations involving cerebellar connections, the identification of potential encephalic lesions that can lead to these degenerations and correlation of the clinical manifestations with imaging findings that reflect this involvement. Methods: In this report, we review the neuroanatomical knowledge that provides a basis for identifying potential lesions that can result in these degenerations involving cerebellar structures. Results: Hypertrophic olivary degeneration results from an injury that interrupts any of the components of the Guillain-Mollaret triangle. In this work, we describe cases of lesions in the dentate nucleus and central tegmental tract. The crossed cerebellar diaschisis presents specific imaging findings and clinical correlations associated with its acute and chronic phases. The Wallerian degeneration of the middle cerebellar peduncle is illustrated by fiber injury of the pontine cerebellar tracts. A T2-hyperintensity in the dentate nucleus due to a thalamic acute lesion (in ventral lateral nuclei) is also described. Each condition described here is documented by MRI images and is accompanied by teaching points and an anatomical review of the pathways involved. Conclusion: Neurologists and radiologists need to become familiar with the diagnosis of these conditions since their presentations are peculiar and often subtle, and can easily be misdiagnosed as ischemic events, degenerative disease, demyelinating disease or even tumors.

RESUMO Degenerações transaxonais resultam da morte neuronal ou da interrupção de conexões sinápticas entre estruturas neurais. Essas degenerações não são comuns, mas podem ser reconhecidas por imagens de ressonância magnética convencional. Objetivo: Os objetivos de aprendizado desta revisão incluem o reconhecimento das características de imagem de degenerações transaxonais envolvendo conexões cerebelares, a identificação de possíveis lesões encefálicas que podem levar a essas degenerações e a correlação das manifestações clínicas com os achados de imagem que refletem esse envolvimento. Métodos: Neste artigo, revisamos conhecimentos neuroanatômicos que fornecem a base para identificar possíveis lesões que podem resultar nessas degenerações envolvendo estruturas cerebelares. Resultados: A degeneração olivar hipertrófica resulta de uma lesão que interrompe algum dos componentes do triângulo de Guillain-Mollaret. Neste trabalho, descrevemos casos de lesões no núcleo denteado e no trato tegmentar central. A diásquise cerebelar cruzada apresenta achados de imagem específicos e correlações clínicas associadas às suas fases aguda e crônica. A degeneração walleriana dos pedúnculos cerebelares médios é ilustrada pela lesão dos tratos pontino-cerebelares. Uma hiperintensidade em T2 do núcleo denteado devido a uma lesão talâmica aguda (no núcleo ventrolateral) também é descrita. Cada condição aqui descrita é documentada por imagens de ressonância magnética e é acompanhada por pontos didáticos e uma revisão anatômica das vias envolvidas. Conclusão: Neurologistas e radiologistas precisam estar familiarizados com o diagnóstico dessas condições, uma vez que suas apresentações são peculiares e frequentemente sutis, e podem ser facilmente equivocadamente diagnosticadas como lesões isquêmicas, doenças degenerativas, desmielinizantes, ou mesmo tumorais.

Neuralgia del Trigémino / Trigeminal neuralgia

Resumen La neuralgia del trigémino (NT) es una enfermedad cuya prevalencia es alta y corresponde a un porcentaje importante de neuralgias faciales; en donde las personas más afectadas son mayores de 50 años. Su manifestación clínica suele ser de cuadros de dolor facial severo y recurrentes, unilateral; en la distribución de una o más divisiones del nervio trigémino y no se explica con otro diagnóstico. El diagnóstico se basa en el cuadro clínico y usualmente no se encuentra déficit sensorial, sin embargo, si está presente se deben hacer neuroimágenes para descartar otras causas. En primera instancia está el manejo farmacológico. La carbamazepina se ha establecido como efectivo, llegando a producir un alivio del dolor dentro de las 24 horas. Cuando la farmacoterapia falla, se opta por la cirugía que se divide generalmente en dos: técnicas que destruyen la porción sensitiva del nervio; y la descompresión microvascular (DMV), que es la que tiene mejores resultados.

Abstract Trigeminal neuralgia is a disease whose prevalence is high and corresponds to a significant percentage of facial neuralgia; where the most affected people are over 50 years old. The clinical picture is usually of episodes of severe and recurring facial pain, unilateral; in the distribution of one or more divisions of the trigeminal nerve and this is not explained with another diagnosis. Diagnosis is based on the clinic and usually no sensory deficit is found, however, if present, neuroimaging should be done to rule out other causes. In the first instance is the pharmacological management. Carbamazepine has been established as effective, leading to pain relief within 24 hours. When pharmacological therapy fails, surgery is generally divided into two: techniques that destroy the sensitive portion of the nerve and microvascular decompression, which has the best results.

Diffuse Intrinsic Pontine Gliomas Exhibit Cell Biological and Molecular Signatures of Fetal Hindbrain-Derived Neural Progenitor Cells / 神经科学通报·英文版

Diffuse intrinsic pontine glioma (DIPG) is the main cause of brain tumor-related death among children. Until now, there is still a lack of effective therapy with prolonged overall survival for this disease. A typical strategy for preclinical cancer research is to find out the molecular differences between tumor tissue and para-tumor normal tissue, in order to identify potential therapeutic targets. Unfortunately, it is impossible to obtain normal tissue for DIPG because of the vital functions of the pons. Here we report the human fetal hindbrain-derived neural progenitor cells (pontine progenitor cells, PPCs) as normal control cells for DIPG. The PPCs not only harbored similar cell biological and molecular signatures as DIPG glioma stem cells, but also had the potential to be immortalized by the DIPG-specific mutation H3K27M in vitro. These findings provide researchers with a candidate normal control and a potential medicine carrier for preclinical research on DIPG.

Clinical Factors Associated with Videofluoroscopic Swallowing Study Findings in Stroke Patients / 대한연하장애학회지

OBJECTIVE: To examine the clinical factors and brain lesion locations related to the patterns of dysphagia in stroke patients in a rehabilitation hospital. METHODS: The medical records of 116 stroke patients who underwent a videofluoroscopic swallowing study (VFSS) between January 2010 and January 2015 in a rehabilitation hospital were reviewed retrospectively. The swallowing-related parameters were assessed using a VFSS. The brain lesion locations were classified as the cortex, basal ganglia, thalamus, midbrain, pons, medulla, cerebellum, and others (subarachnoid or intraventricular hemorrhage). The ambulation ability was assessed using functional ambulation categories (FACs). The independence in the activities of daily living and the degree of cognitive impairment were assessed using the Korean versions of the modified Barthel index (K-MBI) and Mini-Mental State Examination (K-MMSE), respectively. After adjusting for the potential confounding factors in multivariate analysis, the odds ratios and confidence intervals of the stroke brain lesions were calculated and the clinical factors for predicting the VFSS findings were determined. RESULTS: Among the 116 patients, 35 (27%) had an impaired oral stage and 58 (50%) had aspiration. The impaired oral stage was associated significantly with the onset time, basal ganglia stroke, dietary and fluid intake methods at the time of the VFSS, symptoms of dysphagia, FACs, K-MBI, and K-MMSE. Aspiration was correlated with a pontine stroke, methods of dietary and fluid intakes at the time of the VFSS, symptoms of dysphagia, FACs, and K-MBI. Multivariate analysis showed that the pontine stroke and methods of dietary and fluid intake at the time of VFSS predicted aspiration after adjusting for the potential confounding factors. In subgroup analysis of the diet type, the liquid and semisolid aspirations were correlated with the dietary and fluid intake methods and pontine stroke, respectively. CONCLUSION: Patients with a pons lesion stroke, who are on a modified diet (fluid thickening and tube feeding), have higher risks of aspiration. This provides evidence for precise clinical reasoning in this specific patient group.

A Case of Anti-N-Methyl-D-Aspartate Receptor Encephalitis Associated with Glioma of the Pons

No abstract available.

An MRI-Based Quantification for Correlation of Imaging Biomarker and Clinical Performance in Chronic Phase of Carbon Monoxide Poisoning

PURPOSE: The purpose of this study was to determine the relation between quantitative magnetic resonance imaging biomarkers, and clinical performances in chronic phase of carbon monoxide intoxication. MATERIALS AND METHODS: Eighteen magnetic resonance scans and cognitive evaluations were performed, on patients with carbon monoxide intoxication in chronic phase. Apparent diffusion coefficient (ADC) ratios of affected versus unaffected centrum semiovale, and corpus callosum were obtained. Signal intensity (SI) ratios between affected centrum semiovale, and normal pons in T2-FLAIR (fluid-attenuated inversion recovery) images were obtained. The Mini-Mental State Exam, and clinical outcome scores were assessed. Correlation coefficients were calculated, between MRI and clinical markers. Patients were further classified into poor-outcome and good-outcome groups based on clinical performance, and imaging parameters were compared. T2-SI ratio of centrum semiovale was compared, with that of 18 sex-matched and age-matched controls. RESULTS: T2-SI ratio of centrum semiovale was significantly higher in the poor-outcome group, than that in the good-outcome group and was strongly inversely correlated, with results from the Mini-Mental State Exam. ADC ratios of centrum semiovale were significantly lower in the poor outcome group than in the good outcome group, and were moderately correlated with the Mini-Mental State Exam score. CONCLUSION: A higher T2-SI and a lower ratio of ADC values in the centrum semiovale, may indicate presence of more severe white matter injury and clinical impairment. T2-SI ratio and ADC values in the centrum semiovale, are useful quantitative imaging biomarkers for correlation with clinical performance in individuals with carbon monoxide intoxication.

Ramsay Hunt Syndrome Complicated by Meningoencephalitis and Radiologic findings: a Rare Case Report

Ramsay Hunt syndrome with the complication of encephalitis or meningoencephalitis is rarely reported and uncommon in immunocompetent patients. The radiological manifestations of such cases usually involve the cerebellum and brainstem or exhibit the absence of any abnormality. We report a case of a 78-year-old immunocompetent man hospitalized with Ramsay Hunt syndrome, who later developed meningoencephalitis. The cerebrospinal fluid-study excluded other causes of meningoencephalitis, and the clinical diagnosis indicated varicella zoster virus meningoencephalitis. Magnetic resonance imaging revealed increased signal intensities in the bilateral temporal lobe, midbrain, and pons on T2-weighted imaging, and T2 fluid attenuated inversion recovery and contralateral asymmetric pachymeningeal enhancement. Contrast-enhanced T1-weighted imaging revealed ipsilateral facial nerve enhancement.

Comparison of Dysphagia Between Infratentorial and Supratentorial Stroke Patients

OBJECTIVE: To compare dysphagia between infratentorial stroke patients and supratentorial stroke patients. METHODS: Subjects of this study were patients with post-stroke dysphagia (PSD) who were admitted to our medical institution between May 2014 and June 2017. We evaluated a total of 64 patients with PSD. A videofluoroscopic swallowing study (VFSS) was performed to determine dysphagia severity. We measured the following parameters: pharyngeal transit time (PTT), post-swallow pharyngeal remnant, Penetration Aspiration Scale (PAS) scores, and Functional Dysphagia Scale (FDS). We analyzed patient's results from VFSS performed at admission. All VFSS images were recorded using a camcorder running at 30 frames per second. An AutoCAD 2D screen was used to measure post-swallow pharyngeal remnant. RESULTS: In this study, PTT and FDS were similar (p>0.05) between infratentorial stroke patients and supratentorial stroke patients. However, there were significant differences in pharyngeal remnant and PAS scores between the two groups (p<0.01 and p<0.05, respectively). CONCLUSION: Both pharyngeal remnant and PAS score registered higher levels from VFSS test for infratentorial stroke patients than those for supratentorial stroke patients. This suggests greater chances of problems occurring with swallowing, the major functions of pons. Thus, clinicians should pay particular attention to active dysphagia evaluation and treatment in PSD of infratentorial stroke patients.

Trigeminal Neuralgia Resulting from Delayed Cervical Cord Compression after Acute Traumatic Fracture of Odontoid Process / 대한신경손상학회지

Trigeminal neuralgia is caused by compression of trigeminal nerve root and it leads to demyelination gradually. It was almost idiopathic and occurred unexpected. The upper cervical spinal cord contains the spinal trigeminal tract and nucleus. Fibers with cell bodies in the trigeminal ganglion enter in the upper pons and descend caudally to C2 level. We experienced a rare patient with facial pain, which was paroxysmal attack with severe pain after a clear event, cervical spinal injury (C2). So, this case reminds us of a possible cause of trigeminal neuralgia after a trauma of the head and neck.

An Anti-aquaporin 4 Positive Longitudinally Extensive Transverse Myelitis with Antecedent Necrotizing Pneumonia Associated with S. aureus

A 53-year-old male patient presented with quadriparesis during pulmonological hospitalization for the treatment of S. aureus associated necrotizing pneumonia. He was diagnosed with the aquaporin-4 (AQP4) positive longitudinally extensive transverse myelitis from pons to T3 level. Despite the administration of intravenous methylprednisolone and plasma exchange with appropriate antibiotics, the patient's neurological condition deteriorated and he died. Our case implies that an S. aureus associated necrotizing pneumonia can trigger an AQP4 positive neuromyelitis optica spectrum disorder and contribute to the devastating course.

Metronidazole-Induced Encephalopathy with Thiamine Deficiency

Metronidazole-induced encephalopathy (MIE) can be caused by excessive dose or prolonged metronidazole administration. The signal abnormalities in the cerebellar dentate nuclei, midbrain, dorsal pons and corpus callosum on magnetic resonance imaging are considered as the characteristic feature of MIE. Although the mechanism of MIE remains to be elucidated, various hypothesis have been proposed including the role of metronidazole as a thiamine antagonist. Here we report a 58-year-old woman with MIE who coincidentally presented with thiamine deficiency.

Acute combined central and peripheral nervous system demyelination: a case report / 고신대학교의과대학학술지

Guillain-Barré syndrome (GBS) and acute disseminated encephalomyelitis (ADEM) are demyelinating neurologic disorders with different target organs. Although they share similar pathogenetic mechanism, reports of simultaneous occurrence of the 2 disorders are rare. A 2 year 6 month old girl visited our hospital for fever, cough, and general weakness. Although the muscle power of extremities showed mild weakness and voiding difficulty, initial deep tendon reflex of both knees and ankles was normal. A nerve conduction study to evaluate the weakness revealed the absence of F waves. Cerebrospinal fluid analysis demonstrated pleocytosis with lymphocyte predominance and elevated protein levels. Magnetic resonance imaging showed abnormal T2 hyperintensity in pons, medulla and spinal cord. Serum anti-GD1b antibody was positive. Based on clinical findings, laboratory findings, nerve conduction study, and neuroimaging, the diagnosis of GBS and ADEM was made. This is the first case of GBS accompanied by ADEM in Korea.

Secondary Short-Lasting Unilateral Neuralgiform Headache with Conjunctival Injection and Tearing: A New Case and a Literature Review

Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) is a primary headache syndrome with an unclear pathogenesis. However, there is increasing evidence in the literature for secondary SUNCT being attributable to certain known lesions. We explored the possible neurobiological mechanism underlying SUNCT based on all reported cases of secondary SUNCT for which detailed information is available. Here we report a case of neuromyelitis optica spectrum disorders that had typical symptoms of SUNCT that might have been attributable to involvement of the spinal nucleus of the trigeminal nerve. We also review cases of secondary SUNCT reported in the English-language literature and analyze them for demographic characteristics, clinical features, response to treatment, and imaging findings. The literature review shows that secondary SUNCT can derive from a neoplasm, vascular disease, trauma, infection, inflammation, or congenital malformation. The pons with involvement of the trigeminal root entry zone was the most commonly affected region for inducing secondary SUNCT. In conclusion, the neurobiology of secondary SUNCT includes structures such as the nucleus and the trigeminal nerve with its branches, suggesting that some cases of primary SUNCT have underlying mechanisms that are related to existing focal damage that cannot be visualized.

Association of Brain Lesions and Videofluoroscopic Dysphagia Scale Parameters on Patients With Acute Cerebral Infarctions

OBJECTIVE: To investigate the characteristics and risk factors of dysphagia using the videofluoroscopic dysphagia scale (VDS) with a videofluoroscopic swallowing study (VFSS) in patients with acute cerebral infarctions. METHODS: In this retrospective study, the baseline VFSS in 275 stroke patients was analyzed. We divided patients into 8 groups according to lesion areas commonly observed on brain magnetic resonance imaging. Dysphagia characteristics and severity were evaluated using the VDS. We also analyzed the relationship between clinical and functional parameters based on medical records and VDS scores. RESULTS: In comparison studies of lesions associated with swallowing dysfunction, several groups with significant differences were identified. Apraxia was more closely associated with cortical middle cerebral artery territory lesions. Vallecular and pyriform sinus residue was more common with lesions in the medulla or pons. In addition, the results for the Korean version of the Modified Barthel Index (K-MBI), a functional assessment tool, corresponded to those in the quantitative evaluation of swallowing dysfunctions. CONCLUSION: A large cohort of patients with cerebral infarction was evaluated to determine the association between brain lesions and swallowing dysfunction. The results can be used to establish a specific treatment plan. In addition, the characteristic factors associated with swallowing dysfunctions were also confirmed.

Changes in Diffusion Metrics of the Red Nucleus in Chronic Stroke Patients With Severe Corticospinal Tract Injury: A Preliminary Study

OBJECTIVE: To explore plastic changes in the red nucleus (RN) of stroke patients with severe corticospinal tract (CST) injury as a compensatory mechanism for recovery of hand function. METHODS: The moderate group (MG) comprised 5 patients with synergistic hand grasp movement combined with limited extension, and the severe group (SG) included 5 patients with synergistic hand grasp movement alone. The control group (CG) included 5 healthy subjects. Motor assessment was measured by Motricity Index (MI). Diffusion tensor imaging was analyzed using fractional anisotropy (FA) and radial diffusivity (RD) in the individual regions of interest (ROIs)—bilateral internal capsule and anterior pons for CST injury and bilateral RN for rubrospinal tract (RST) injury. RESULTS: The SG showed a significantly lower MI score than the MG mainly due to differences in hand subscores. Significantly reduced FA was observed in both MG and SG compared with CG, while SG showed increased MD and RD in the affected ROIs of CST, and increased FA on the unaffected side compared with CG. However, in the RN ROI, a significantly increased FA and decreased RD on the unaffected side similar to the affected side were found only in the SG. The relative index of FA was lower and RD in SG was higher than in CG in RST. CONCLUSION: The diffusion metrics of RST showed changes in patients with severe CST injury, suggesting that RST may play a role in the recovery of hand function in patients with severe CST injury.

Pontine Hypoplasia and Cri-du-chat Syndrome in a Preterm Infant / 고신대학교의과대학학술지

A premature infant with gestational age 36⁺⁴ weeks was admitted with respiratory distress syndrome. Surfactant and ventilation were firstly done to improve his respiration. After extubation, weak, high-pitched cry and asymmetric face with micrognathia and hypertelorism were detected. Therefore, cytogenetic analysis was performed, and his karyotype was 46, XY, del(5) (p14p15.33). Pontine hypoplasia was detected on cranial magnetic resonance imaging (MRI). Therefore, karyotyping and cranial MRI should be performed in case of preterm infants with suspicion of Cri-du-chat syndrome (CdCS).

Glucose Hypometabolism in Hippocampal Subdivisions in Alzheimer's Disease: A Pilot Study Using High-Resolution ¹⁸F-FDG PET and 7.0-T MRI

BACKGROUND AND PURPOSE: Atrophy of the hippocampus is an important clinical diagnostic marker of Alzheimer's disease (AD), and so assessments of hippocampal activity and its subdivisions might provide invaluable information. This study compared the glucose metabolism of hippocampal subdivisions in mild-AD patients and healthy controls. METHODS: High-resolution T2*-weighted gradient-echo magnetic resonance imaging (MRI) images and ¹⁸F-fluorodeoxyglucose (FDG) positron-emission tomography (PET) images were acquired using 7.0-T MRI and high-resolution research tomograph FDG-PET, respectively, in 9 early-stage AD patients and 10 healthy subjects. The hippocampal body was divided into three equal parts (anterior, middle, and posterior), and in each part a region of interest (ROI) was drawn over the cornus ammonis (CA)1, CA2/3, CA4/dentate gyrus (DG), and subiculum. The standardized uptake values of the hippocampal subdivisions were calculated for each ROI as ratios relative to the pons standardized uptake value. Statistical analysis was conducted using the Mann-Whitney U test. RESULTS: Patients with early-stage AD patients showed significantly less metabolic activity than healthy controls focally in the middle (p=0.050) and posterior (p=0.034) CA2/3 regions of the right hippocampus, and significantly less activity throughout the left hippocampal body in the anterior CA2/3 (p=0.027) and CA4/DG (p=0.027) regions, the middle CA1 region (p=0.011), and the posterior CA1 (p=0.034), CA2/3 (p=0.007), and CA4/DG (p=0.014) regions. CONCLUSIONS: It was possible to use high-resolution PET-MRI fusion images to identify hippocampus subdivisions and assess glucose metabolism in the subfields. Reductions in metabolic activity were found to vary along the hippocampal axis in early-stage AD patients.