Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
medRxiv ; 2024 Feb 18.
Article in English | MEDLINE | ID: mdl-38405699

ABSTRACT

Background and Objectives: GAA-FGF14 ataxia (SCA27B) is a recently reported late-onset cerebellar ataxia (LOCA) caused by a GAA repeat expansion in intron 1 of the FGF14 gene. Initial studies reviewing MR images of GAA-FGF14 ataxia patients revealed variable degree of cerebellar atrophy in 74-97% of them. A more detailed brain imaging characterization of GAA-FGF14 ataxia is now needed to provide 1) supportive diagnostic features and earlier disease recognition and 2) further information about the pathophysiology of the disease. Methods: We reviewed the brain MRIs of 35 patients (median age at MRI 63 years; range 28-88 years; 16 females) from Quebec (n=27), Nancy (n=3), Perth (n=3) and Bengaluru (n=2) including longitudinal studies for 7 subjects. We performed qualitative analyses to assess the presence and degree of atrophy in vermis, cerebellar hemispheres, brainstem, cerebral hemispheres, and corpus callosum, as well as white matter involvement. Following the identification of the superior cerebellar peduncles involvement, we verified its presence in 54 GAA-FGF14 ataxia patients from four independent cohorts (Tübingen n=29; Donostia n=12; Innsbruck n=7; Cantabria n=6). To assess lobular atrophy, we also performed quantitative cerebellar segmentation in 5 subjects and 5 age-matched controls. Results: Cerebellar atrophy of variable degree was documented in 33 subjects (94.3%); limited to the vermis in 11 subjects, extended to the hemispheres in 22. We observed bilateral involvement of the superior cerebellar peduncles (SCPs) in 22 subjects (62.8%). We confirmed this finding in 30/54 (55.6%) GAA-FGF14 positive subjects from the validation cohorts. Additional findings were: cerebral atrophy in 15 subjects (42.9%), ventricular enlargement in 13 (37.1%), corpus callosum thinning in 7 (20%), and brainstem atrophy in 1 (2.8%). Cerebellar segmentation showed reduced volumes of lobules X and IV in affected individuals. Discussion: Our study confirms that cerebellar atrophy is a key feature of GAA-FGF14 ataxia. The frequent SCP involvement observed in different cohorts may be specific to GAA-FGF14 ataxia, and its detection can support and accelerate the diagnosis. The predominant involvement of vestibulocerebellar lobule X correlates with the finding of downbeat nystagmus frequently observed in GAA-FGF14 ataxia patients.

2.
Neurosurg Focus ; 48(2): E7, 2020 02 01.
Article in English | MEDLINE | ID: mdl-32006945

ABSTRACT

OBJECTIVE: The functional importance of the superior temporal lobe at the level of Heschl's gyrus is well known. However, the organization and function of these cortical areas and the underlying fiber tracts connecting them remain unclear. The goal of this study was to analyze the area formed by the organization of the intersection of Heschl's gyrus-related fiber tracts, which the authors have termed the "Heschl's gyrus fiber intersection area" (HGFIA). METHODS: The subcortical connectivity of Heschl's gyrus tracts was analyzed by white matter fiber dissection and by diffusion tensor imaging tractography. The white matter tracts organized in relation to Heschl's gyrus were isolated in 8 human hemispheres from cadaveric specimens and in 8 MRI studies in 4 healthy volunteers. In addition, these tracts and their functions were described in the surgical cases of left temporal gliomas next to the HGFIA in 6 patients who were awake during surgery and underwent intraoperative electrical stimulation mapping. RESULTS: Five tracts were observed to pass through the HGFIA: the anterior segment of the arcuate fasciculus, the middle longitudinal fasciculus, the acoustic radiation, the inferior fronto-occipital fasciculus, and the optic radiation. In addition, U fibers originating at the level of Heschl's gyrus and heading toward the middle temporal gyrus were identified. CONCLUSIONS: This investigation of the HGFIA, a region where 5 fiber tracts intersect in a relationship with the primary auditory area, provides new insights into the subcortical organization of Wernicke's area. This information is valuable when a temporal surgical approach is planned, in order to assess the surgical risk related to language disturbances.


Subject(s)
Auditory Cortex/diagnostic imaging , Auditory Cortex/physiology , Auditory Pathways/diagnostic imaging , Auditory Pathways/physiology , Auditory Perception/physiology , Language , Adult , Aged , Aged, 80 and over , Auditory Cortex/anatomy & histology , Auditory Pathways/anatomy & histology , Female , Humans , Male , Middle Aged , Nerve Fibers/physiology , Neural Pathways/diagnostic imaging , Neural Pathways/physiology
3.
Neurosurgery ; 83(6): 1209-1218, 2018 12 01.
Article in English | MEDLINE | ID: mdl-29351666

ABSTRACT

BACKGROUND: Recent glioma surgery series with intraoperative electrical stimulation (IES) language mapping have demonstrated high rates of postoperative memory impairment, raising a question regarding the efficacy of this approach to preserve memory. OBJECTIVE: To evaluate if intraoperative identification and preservation of verbal memory sites with IES mapping in diffuse gliomas in eloquent areas consistently protect patients from long-term postoperative decline in short-term memory. METHODS: A cohort of 16 subjects with diffuse low-grade or anaplastic gliomas that were operated with IES and intraoperative evaluation of language and verbal memory (cohort A) was matched by tumor side, pathology, and radiotherapy with a cohort of 16 subjects that were operated with IES and evaluation of language (cohort B). Detailed neuropsychological assessment was performed before and 6 mo after surgery. RESULTS: Intraoperative memory mapping was a strong predictor of verbal memory prognosis. In cohort A, 4 patients (26.7%) had a decline of at least one of the 4 short-term memory tests evaluated. In cohort B, 11 patients (73.3%) had a decline of at least one of the 4 tests. This difference was statistically significant in multivariate analysis (P = .022; odds ratio = 9.88; 95% confidence interval = 1.39-70.42). CONCLUSION: Verbal memory areas identified intraoperatively with the current paradigm are critically involved in verbal memory, as memory impairment can be significantly reduced by adapting the resection to avoid those memory areas. Incorporation of verbal memory evaluation in stimulation mapping protocols might assist in reducing postoperative sequelae and preserving the patient's quality of life.


Subject(s)
Brain Neoplasms/surgery , Glioma/surgery , Intraoperative Neurophysiological Monitoring/methods , Memory Disorders/prevention & control , Neurosurgical Procedures/adverse effects , Adult , Brain Mapping/methods , Cohort Studies , Electric Stimulation/methods , Female , Humans , Male , Memory/physiology , Memory Disorders/etiology , Middle Aged , Multivariate Analysis , Prognosis
4.
World Neurosurg ; 105: 1033.e1-1033.e5, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28602887

ABSTRACT

BACKGROUND: Modern sign languages used by deaf people are fully expressive, natural human languages that are perceived visually and produced manually. The literature contains little data concerning human brain organization in conditions of deficient sensory information such as deafness. CASE DESCRIPTION: A deaf-mute patient underwent surgery of a left temporoinsular low-grade glioma. The patient underwent awake surgery with intraoperative electrical stimulation mapping, allowing direct study of the cortical and subcortical organization of sign language. We found a similar distribution of language sites to what has been reported in mapping studies of patients with oral language, including 1) speech perception areas inducing anomias and alexias close to the auditory cortex (at the posterior portion of the superior temporal gyrus and supramarginal gyrus); 2) speech production areas inducing speech arrest (anarthria) at the ventral premotor cortex, close to the lip motor area and away from the hand motor area; and 3) subcortical stimulation-induced semantic paraphasias at the inferior fronto-occipital fasciculus at the temporal isthmus. CONCLUSIONS: The intraoperative setup for sign language mapping with intraoperative electrical stimulation in deaf-mute patients is similar to the setup described in patients with oral language. To elucidate the type of language errors, a sign language interpreter in close interaction with the neuropsychologist is necessary. Sign language is perceived visually and produced manually; however, this case revealed a cross-modal recruitment of auditory and orofacial motor areas.


Subject(s)
Brain Mapping , Brain Neoplasms/surgery , Cerebral Cortex/pathology , Deafness/pathology , Glioma/surgery , Sign Language , Brain Neoplasms/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Deafness/diagnostic imaging , Deafness/physiopathology , Electroencephalography , Female , Glioma/diagnostic imaging , Humans , Magnetic Resonance Imaging , Middle Aged , Neural Pathways/diagnostic imaging
6.
J Neurosurg ; 123(4): 1081-92, 2015 10.
Article in English | MEDLINE | ID: mdl-25955870

ABSTRACT

OBJECT: Little attention has been given to the functional challenges of the insular approach to the resection of gliomas, despite the potential damage of essential neural networks that underlie the insula. The object of this study is to analyze the subcortical anatomy of the insular region when infiltrated by gliomas, and compare it with the normal anatomy in nontumoral hemispheres. METHODS: Ten postmortem human hemispheres were dissected, with isolation of the inferior fronto-occipital fasciculus (IFOF) and the uncinate fasciculus. Probabilistic diffusion tensor imaging (DTI) tractography was used to analyze the subcortical anatomy of the insular region in 10 healthy volunteers and in 22 patients with insular Grade II and Grade III gliomas. The subcortical anatomy of the insular region in these 22 insular gliomas was compared with the normal anatomy in 20 nontumoral hemispheres. RESULTS: In tumoral hemispheres, the distances between the peri-insular sulci and the lateral surface of the IFOF and uncinate fasciculus were enlarged (p < 0.05). Also in tumoral hemispheres, the IFOF was identified in 10 (90.9%) of 11 patients with an extent of resection less than 80%, and in 4 (36.4%) of 11 patients with an extent of resection equal to or greater than 80% (multivariate analysis: p = 0.03). CONCLUSIONS: Insular gliomas grow in the space between the lateral surface of the IFOF and uncinate fasciculus and the insular surface, displacing and compressing the tracts medially. Moreover, these tracts may be completely infiltrated by the tumor, with a total disruption of the bundles. In the current study, the identification of the IFOF with DTI tractography was significantly associated with the extent of tumor resection. If the IFOF is not identified preoperatively, there is a high probability of achieving a resection greater than 80%.


Subject(s)
Brain Neoplasms/pathology , Cerebral Cortex/anatomy & histology , Diffusion Tensor Imaging , Glioma/pathology , Adult , Aged , Brain Neoplasms/surgery , Cadaver , Female , Glioma/surgery , Humans , Male , Middle Aged , Young Adult
7.
Epilepsy Behav ; 49: 184-8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25986321

ABSTRACT

BACKGROUND: Fat embolism syndrome (FES) is a rare complication of long-bone fractures and joint reconstruction surgery. To the best of our knowledge, we describe the clinical, electrophysiological, neuroimaging, and neuropathological features of the first case of super-refractory nonconvulsive status epilepticus (sr-NCSE) secondary to fat embolism. CLINICAL CASE: An 82-year-old woman was transferred to our intensive care unit because of a sudden decrease of consciousness level, right hemiparesis, and acute respiratory failure in the early postoperative period of knee prosthesis surgery. Brain computed tomography (TC) including angio-CT and CT perfusion was normal. An urgent video-electroencephalography (v-EEG) evaluation showed continuous sharp-and slow-wave at 2.0-2.5 Hz in keeping with the diagnosis of generalized NCSE. Epileptiform discharges ceased after the administration of 5mg of intravenous diazepam, and background activity constituted by diffuse theta waves was observed without clinical improvement. Treatment with levetiracetam (1000 mg/day) and sedation with propofol and midazolam were initiated. Moreover, continuous v-EEG monitoring was also started. Despite antiepileptic therapy, epileptiform activity recurred after the interruption of profound sedation, and valproate and lacosamide were added during the ensuing days. Magnetic resonance imaging (MRI) disclosed small scattered foci of acute ischemic infarcts and diffuse petechiae involving the basal ganglia and pons and centrum semiovale in keeping with fat embolism. Super-refractory nonconvulsive status epilepticus remained without control for 2 weeks. Finally, the patient died. The clinical autopsy revealed a bilateral lung fat embolism associated with a hemorrhagic infarction in the left lower lobe. Fatty lesions were also seen in the intestine and pancreas. Scattered microscopic cerebral infarcts associated with fat emboli in the capillaries were noticed, affecting both supra- and infratentorial structures. In addition, occasional focal areas of ischemic injury showing filiform neurons with reactive astrocytic gliosis background consistent with acute lesions were observed in CA3. CONCLUSIONS: Fat embolism should be considered a potential cause of sr-NCSE. This article is part of a Special Issue entitled "Status Epilepticus".


Subject(s)
Embolism, Fat/complications , Orthopedic Procedures/adverse effects , Status Epilepticus/diagnosis , Status Epilepticus/etiology , Aged, 80 and over , Anticonvulsants/therapeutic use , Electroencephalography , Embolism, Fat/etiology , Fatal Outcome , Female , Humans , Magnetic Resonance Imaging , Status Epilepticus/drug therapy
8.
Clin Anat ; 27(4): 563-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24453050

ABSTRACT

Precise knowledge of the connectivities of the different white matter bundles is of great value for neuroscience research. Our knowledge of subcortical anatomy has improved exponentially during recent decades owing to the development of magnetic resonance diffusion tensor imaging tractography (DTI). Although DTI tractography has led to important progress in understanding white matter anatomy, the precise trajectory and cortical connections of the subcortical bundles remain poorly determined. The recent literature was extensively reviewed in order to analyze the trajectories and cortical terminations of the lateral association fibers of the brain.The anatomy of the following tracts is reviewed: superior longitudinal fasciculus, middle longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, frontal aslant tract, and vertical occipital fasciculus. The functional role of a tract can be inferred from its topography within the brain. Knowing the functional roles of the cortical areas connected by a certain bundle, it is possible to develop new insights into the putative functional properties of such connections.


Subject(s)
Brain/anatomy & histology , Nerve Fibers, Myelinated , Humans
9.
J Neurol Sci ; 327(1-2): 75-9, 2013 Apr 15.
Article in English | MEDLINE | ID: mdl-23465508

ABSTRACT

Idiopathic CD4 lymphocytopenia (ICL) is a syndrome described in patients with low counts of CD4 cells and no other causes for immunosuppression. A few cases of progressive multifocal leukoencephalopathy (PML) have been described in association with this entity. There is no effective treatment for any of them, and the clinical course and outcome are unpredictable. We report on a case of ICL with PML and review the literature, trying to identify the clinical features and the prognosis clues associated to these entities together. A 72-year-old man presented with acute onset gait instability that progressed to a severe cerebellar syndrome with cognitive decline. A cranial MRI showed findings consistent with PML, this diagnosis being confirmed by CSF analyses. Absolute number of CD4+ was 242 cells/µL. An extensive work-up including HIV tests was negative. Ten cases of PML and ICL have previously been reported. Factors contributing to the different outcomes are unknown. Although an effective treatment does not exist for PML, it has been recently demonstrated in vitro that several 5HT2A-receptor antagonists block the JC virus infection. Our patient greatly improved and remains stable 34 months after onset; we describe the potential role of mirtazapine in the treatment of PML.


Subject(s)
Leukoencephalopathy, Progressive Multifocal/complications , Leukoencephalopathy, Progressive Multifocal/diagnosis , T-Lymphocytopenia, Idiopathic CD4-Positive/complications , T-Lymphocytopenia, Idiopathic CD4-Positive/diagnosis , Aged , Humans , Male
10.
Brain Struct Funct ; 218(1): 105-21, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22422148

ABSTRACT

The anatomy of the perisylvian component of the superior longitudinal fasciculus (SLF) has recently been reviewed by numerous diffusion tensor imaging tractography (DTI) studies. However, little is known about the exact cortical terminations of this tract. The aim of the present work is to isolate the different subcomponents of this tract with fiber dissection and DTI tractography, and to identify the exact cortical connections. Twelve postmortem human hemispheres (6 right and 6 left) were dissected using the cortex-sparing fiber dissection. In addition, three healthy brains were analyzed using DTI-based tractography software. The different components of the perisylvian SLF were isolated and the fibers were followed until the cortical terminations. Three segments of the perisylvian SLF were identified: (1) anterior segment, connecting the supramarginal gyrus and superior temporal gyrus with the precentral gyrus, (2) posterior segment, connecting the posterior portion of the middle temporal gyrus with the angular gyrus, and (3) long segment of the arcuate fasciculus that connects the middle and inferior temporal gyri with the precentral gyrus and posterior portion of the inferior and middle frontal gyri. In the present study, three different components of the perisylvian SLF were identified. For the first time, our dissections revealed that each component was connected to a specific cortical area within the frontal, parietal and temporal lobes. By accurately depicting not only the trajectory but also cortical connections of this bundle, it is possible to develop new insights into the putative functional role of this tract.


Subject(s)
Cerebral Cortex/cytology , Diffusion Tensor Imaging , Dissection , Neural Pathways/cytology , Neuroanatomical Tract-Tracing Techniques , Adult , Aged , Cadaver , Frontal Lobe/cytology , Humans , Middle Aged , Parietal Lobe/cytology , Temporal Lobe/cytology , Young Adult
12.
J Neurosurg ; 117(5): 844-50, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22957529

ABSTRACT

Foix-Chavany-Marie syndrome (FCMS) is a rare type of suprabulbar palsy characterized by an automatic-voluntary dissociation of the orofacial musculature. Here, the authors report an original case of FCMS that occurred intraoperatively while resecting the pars opercularis of the inferior frontal gyrus. This 25-year-old right-handed man with an incidentally diagnosed right frontotemporoinsular tumor underwent surgery using an asleep-awake-asleep technique with direct cortical and subcortical electrical stimulation and a transopercular approach to the insula. While resecting the anterior part of the pars opercularis the patient suffered sudden anarthria and bilateral facial weakness. He was unable to speak or show his teeth on command, but he was able to voluntarily move his upper and lower limbs. This syndrome lasted for 8 days. Postoperative diffusion tensor imaging tractography revealed that connections of the pars opercularis of the right inferior frontal gyrus with the frontal aslant tract (FAT) and arcuate fasciculus (AF) were damaged. This case supplies evidence for localizing the structural substrate of FCMS. It was possible, for the first time in the literature, to accurately correlate the occurrence of FCMS to the resection of connections between the FAT and AF, and the right pars opercularis of the inferior frontal gyrus. The FAT has been recently described, but it may be an important connection to mediate supplementary motor area control of orofacial movement. The present case also contributes to our knowledge of complication avoidance in operculoinsular surgery. A transopercular approach to insuloopercular gliomas can generate FCMS, especially in cases of previous contralateral lesions. The prognosis is favorable, but the patient should be informed of this particular hazard, and the surgeon should anticipate the surgical strategy in case the syndrome occurs intraoperatively in an awake patient.


Subject(s)
Deglutition Disorders/etiology , Deglutition Disorders/physiopathology , Dysarthria/etiology , Dysarthria/physiopathology , Encephalomyelitis, Acute Disseminated/etiology , Encephalomyelitis, Acute Disseminated/physiopathology , Facial Paralysis/etiology , Facial Paralysis/physiopathology , Frontal Lobe/physiopathology , Frontal Lobe/surgery , Intraoperative Complications/physiopathology , Motor Cortex/physiopathology , Postoperative Complications/physiopathology , Adult , Brain Mapping , Brain Neoplasms/surgery , Diffusion Tensor Imaging , Electric Stimulation , Glioma/surgery , Humans , Magnetic Resonance Imaging , Male , Movement , Neural Pathways/pathology , Neuronavigation , Prognosis , Treatment Outcome
13.
Neurocir. - Soc. Luso-Esp. Neurocir ; 23(3): 104-111, mayo-jun. 2012.
Article in Spanish | IBECS | ID: ibc-110970

ABSTRACT

El manejo de los gliomas difusos OMS grado II (GGII) es a día de hoy controvertido. Algunos autores proponen una actitud expectante, con seguimiento radiológico a largo plazo, otros proponen realizar una biopsia y plantear un tratamiento solo si hay signos clínicos o radiológicos de progresión, y por último otros proponen un tratamiento activo desde el diagnóstico. En los últimos años han aparecido varios estudios que pueden ayudar a aclarar estas controversias. En este trabajo se revisa la literatura reciente con a intención de aclarar algunos puntos controvertidos en el manejo de los GGII. Las secuencias convencionales de resonancia magnética (RM) y otras técnicas de neuroimagen más recientes, como la espectroscopia multivoxel o la tomografía por emisión de positrones (PET) con metionina, carecen de la fiabilidad suficiente para realizar un diagnóstico definitivo de GGII. La biopsia estereotáxica es poco invasiva, pero conduce a errores diagnósticos en GGII hasta en el 71% de los casos, lo que se ha asociado a errores en el muestreo y a la variabilidad interobservador por la escasa muestra obtenida. Por todo ello, se considera actualmente que el diagnóstico definitivo de GGII solo se consigue mediante el análisis histológico de la muestra obtenida tras la extirpación máxima del tumor. Respecto al impacto pronóstico de la cirugía, no existe evidencia clase I, pero hay fuertes indicios provenientes de estudios de cohorte con gran número de pacientes y seguimiento a largo plazo de que la extirpación extensa tiene un impacto positivo en la supervivencia y en el tiempo hasta la malignización del tumor. El tratamiento quirúrgico es también efectivo para (..) (AU)


Subject(s)
Humans , Electric Stimulation/methods , Glioma/surgery , Neoplasms, Neuroepithelial/surgery , Epilepsy/prevention & control
14.
J Anat ; 219(4): 531-41, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21767263

ABSTRACT

Classical fiber dissection of post mortem human brains enables us to isolate a fiber tract by removing the cortex and overlying white matter. In the current work, a modification of the dissection methodology is presented that preserves the cortex and the relationships within the brain during all stages of dissection, i.e. 'cortex-sparing fiber dissection'. Thirty post mortem human hemispheres (15 right side and 15 left side) were dissected using cortex-sparing fiber dissection. Magnetic resonance imaging study of a healthy brain was analyzed using diffusion tensor imaging (DTI)-based tractography software. DTI fiber tract reconstructions were compared with cortex-sparing fiber dissection results. The fibers of the superior longitudinal fasciculus (SLF), inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) were isolated so as to enable identification of their cortical terminations. Two segments of the SLF were identified: first, an indirect and superficial component composed of a horizontal and vertical segment; and second, a direct and deep component or arcuate fasciculus. The IFOF runs within the insula, temporal stem and sagittal stratum, and connects the frontal operculum with the occipital, parietal and temporo-basal cortex. The UF crosses the limen insulae and connects the orbito-frontal gyri with the anterior temporal lobe. Finally, a portion of the ILF was isolated connecting the fusiform gyrus with the occipital gyri. These results indicate that cortex-sparing fiber dissection facilitates study of the 3D anatomy of human brain tracts, enabling the tracing of fibers to their terminations in the cortex. Consequently, it is an important tool for neurosurgical training and neuroanatomical research.


Subject(s)
Brain/anatomy & histology , Dissection/methods , Nerve Fibers , Neural Pathways/anatomy & histology , Aged , Aged, 80 and over , Humans
15.
AJR Am J Roentgenol ; 196(3): W316-25, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21343482

ABSTRACT

OBJECTIVE: The objective of this article is to present a comprehensive review of apophysitis of the lower limb regarding anatomy, physiopathology, clinical findings, differential diagnosis, and imaging features with special emphasis on MRI. CONCLUSION: Apophysitis, which is inflammation of the traction epiphysis resulting from chronic trauma, is a common abnormality that affects the growing child. Understanding the physiopathology of apophysitis is essential for a precise diagnosis on MRI. Accurate identification of key MRI features of this entity may prevent misdiagnosis and inappropriate management of apophysitis.


Subject(s)
Athletic Injuries/diagnosis , Epiphyses/injuries , Leg Injuries/diagnosis , Magnetic Resonance Imaging/methods , Osteochondritis/diagnosis , Athletic Injuries/physiopathology , Diagnosis, Differential , Humans , Leg Injuries/physiopathology , Osteochondritis/physiopathology
16.
Am J Psychiatry ; 167(4): 451-8, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20160006

ABSTRACT

OBJECTIVE: Impaired cognitive function has been identified as a core feature of schizophrenia. However, a significant proportion of patients do not show any cognitive deficits. The aim of this study was to assess if there were differences in white matter integrity between patients with and without cognitive impairment. METHOD: A diffusion tensor imaging study and neurocognitive assessment were conducted in 49 patients with first-episode psychosis and 41 healthy comparison subjects. Subjects were assessed using the Continuous Performance Test, the Grooved Pegboard Test, the Rey Auditory Verbal Learning Test, and the Trail Making Test Part B. For each test, the patient sample was subdivided according to performance, with those scoring more than one standard deviation below the normative mean categorized as impaired. For each cognitive domain, white matter fractional anisotropy in deficit and nondeficit subgroups was compared using a voxel-based analysis. A nonparametric statistical method, controlling for multiple comparisons, was applied. RESULTS: Impairment on the Trail Making Test Part B was associated with reduced fractional anisotropy in the right/left anterior thalamic radiation and inferior fronto-occipital fasciculus, forceps minor, and left superior and inferior longitudinal fasciculi. Patients exhibiting Grooved Pegboard Test impairment showed reduced fractional anisotropy in the forceps minor, inferior fronto-occipital fasciculus, anterior thalamic radiation, and corticospinal and corticopontine tracts. Impaired performance on the Rey Auditory Verbal Learning Test and Continuous Performance Test was not associated with significant differences in fractional anisotropy. CONCLUSION: Deficits in executive and motor functioning in patients with first-episode psychosis are associated with reductions in white matter integrity in the major fasciculi that connect the frontal and temporal cortices as well as in pathways connecting cortical and subcortical regions. Their presence at the onset of illness, in minimally medicated patients, indicates that these findings are not attributable to effects of chronic illness or its treatment.


Subject(s)
Brain/anatomy & histology , Cognition Disorders/diagnosis , Cognition Disorders/etiology , Psychotic Disorders/psychology , Adolescent , Adult , Female , Functional Laterality/physiology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests , Psychomotor Performance/physiology , Severity of Illness Index , Young Adult
17.
Neuroimage ; 49(1): 199-204, 2010 Jan 01.
Article in English | MEDLINE | ID: mdl-19619664

ABSTRACT

OBJECTIVE: Disruptions in white matter structure have consistently been shown in schizophrenia--but mainly in patients in whom the illness is well-established. In order to determine whether white matter abnormalities are present at illness onset, and to minimise the potentially confounding effects of chronic illness and treatment, we used diffusion tensor imaging to study a large cohort of first episode psychotic patients who were medication-naive. METHODS: Sixty two first episode patients and 54 controls matched on age, sex, years of education and laterality index underwent diffusion tensor imaging. Data were acquired on a GE Signa NVi 1.5 Tesla System. Fractional anisotropy maps were generated on a voxel-by-voxel basis. An optimized voxel-based morphometry technique was conducted with two-stage registration approach. Group differences were examined using a non-parametric statistical method. RESULTS: The voxelwise analysis revealed four clusters where fractional anisotropy values were significantly lower in patients than controls. These were localised bilaterally to regions of white matter corresponding to superior and inferior longitudinal fasciculus, forceps major, anterior and superior thalamic radiation and corpus callosum. CONCLUSIONS: Reductions in white matter integrity are present early in the course of the schizophrenia and localised in fascicule that connect brain regions implicated in the disorder.


Subject(s)
Brain/pathology , Psychotic Disorders/pathology , Adolescent , Adult , Anisotropy , Antipsychotic Agents/therapeutic use , Chronic Disease , Diagnosis, Dual (Psychiatry) , Diffusion Magnetic Resonance Imaging , Female , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Psychiatric Status Rating Scales , Schizophrenia/pathology , Substance-Related Disorders/pathology , Young Adult
18.
Schizophr Res ; 115(2-3): 191-201, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19796919

ABSTRACT

Evidence so far indicates the consistent association between brain structural abnormalities and schizophrenia already present at the early phases of the illness. This study investigates the specificity of brain structural abnormalities in schizophrenia by using region-of-interest method of volumetric analysis in a heterogeneous sample of schizophrenia spectrum patients at their first break of the illness. 225 subjects, comprising 82 schizophrenia patients, 36 schizophreniform disorder patients and 24 patients with non-schizophrenic non-affective psychoses, and 83 healthy individuals underwent a magnetic resonance imaging brain scan. Quantitative brain morphometric variables were assessed: cortical CSF, lateral ventricle, total brain tissue, white matter and cortical and subcortical gray matter volumes. The contribution of sociodemographic, cognitive and clinical characteristics was controlled. Compared with controls, schizophrenia (P=0.017) and schizophreniform disorder (P=0.023) patients showed an increase in cortical CSF volume. Schizophrenia patients had also markedly enlarged lateral ventricle volume compared to controls (P=0.026). The patients with non-schizophrenic non-affective psychoses did not significantly differ in lateral ventricle and cortical CSF volumes from controls. Compared with controls, schizophrenia and schizophreniform disorder patients demonstrated a significant decrease in total brain tissue (-1.30% and -1.12% respectively). Thalamic volume was reduced (-3.84%) in schizophrenia patients compared to controls (P=0.040). Clinical and cognitive variables were not significantly related with morphological changes. The brain changes found in patients with a first episode of schizophrenia spectrum disorders are robustly associated with the diagnoses of schizophrenia and schizophreniform disorder and are independent of relevant intervening variables.


Subject(s)
Brain/pathology , Psychotic Disorders/pathology , Schizophrenia/pathology , Adolescent , Adult , Analysis of Variance , Brain Mapping , Cerebrospinal Fluid , Cognition Disorders/etiology , Cognition Disorders/pathology , Female , Humans , Image Processing, Computer-Assisted/methods , Longitudinal Studies , Magnetic Resonance Imaging/methods , Male , Middle Aged , Neuropsychological Tests , Psychiatric Status Rating Scales , Retrospective Studies , Statistics as Topic , Young Adult
19.
Clin Rheumatol ; 28(3): 315-20, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19043772

ABSTRACT

Computed tomography (CT)-guided biopsy of the spine is considered a safe, accurate, and relatively inexpensive examination technique. Our purpose was to determine the diagnostic accuracy of CT-guided biopsies exclusively for vertebral osteomyelitis. A retrospective study was performed from a consecutive series of 72 patients with confirmed vertebral osteomyelitis with 46 CT-guided biopsies performed in 40 patients. Biopsy specimens were sent for bacteriologic and cytologic analysis. An adequate specimen for microbiologic examination was not obtained in one case and not enough sample for additional pathologic examination in 17 cases. The mean age of patients was 58 years, with a range of 1-88 years, including 24 men and 16 women. The level of spinal biopsy was thoracic in 18 (40%) and lumbar in 28 (60%). The analysis revealed the infection agent in 20 cases (43% sensitivity). Diagnostic rates obtained in patients with previous antibiotic treatment were significantly lower (23% vs. 60%, p = 0.013). Computed tomography-guided fine-needle aspiration biopsy is an important tool in the diagnostic evaluation of vertebral osteomyelitis. However, this technique yields a lower diagnostic rate than previously reported biopsy of neoplastic vertebral lesions, especially if performed in patients with previous antibiotic treatment.


Subject(s)
Osteomyelitis/pathology , Spinal Diseases/pathology , Tomography, X-Ray Computed/methods , Adolescent , Adult , Aged , Aged, 80 and over , Biopsy, Fine-Needle/methods , Child , Child, Preschool , Female , Humans , Infant , Lumbar Vertebrae/pathology , Male , Middle Aged , Osteomyelitis/diagnostic imaging , Osteomyelitis/microbiology , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Spinal Diseases/diagnostic imaging , Spinal Diseases/microbiology , Thoracic Vertebrae/pathology , Young Adult
20.
Radiographics ; 28(6): 1673-87, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18936029

ABSTRACT

Acute stroke services have been installed in most hospitals in the industrialized world, and dealing with hyperacute stroke has become one of the most frequently performed tasks of the on-call radiologist. Imaging plays a key role in current guidelines for thrombolysis, and knowledge of classic early ischemic signs or depiction of hemorrhage at nonenhanced computed tomography (CT) is necessary (although not sufficient) for a satisfactory imaging study. A modern CT examination must also include perfusion CT and CT angiography. Perfusion CT delineates the ischemic tissue (penumbra) by showing increased mean transit time with decreased cerebral blood flow (CBF) and normal or increased cerebral blood volume (CBV), whereas infarcted tissue manifests with markedly decreased CBF and decreased CBV. CT angiography can depict the occlusion site, help grade collateral blood flow, and help characterize carotid atherosclerotic disease. A complete CT study (nonenhanced CT, perfusion CT, and CT angiography) may be performed and analyzed rapidly and easily by general radiologists using a simple standardized protocol and may even facilitate diagnosis by less experienced radiologists in affected patients.


Subject(s)
Cerebral Angiography/methods , Critical Care/methods , Practice Guidelines as Topic , Stroke/diagnostic imaging , Tomography, X-Ray Computed/methods , Humans , United States
SELECTION OF CITATIONS
SEARCH DETAIL
...