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1.
AJNR Am J Neuroradiol ; 42(5): 868-874, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33602747

RESUMO

BACKGROUND AND PURPOSE: MR imaging has been widely used for the noninvasive evaluation of MS. Although clinical MR imaging sequences are highly effective in showing focal macroscopic tissue abnormalities in the brains of patients with MS, they are not specific to myelin and correlate poorly with disability. We investigated direct imaging of myelin using a 2D adiabatic inversion recovery ultrashort TE sequence to determine its value in assessing disability in MS. MATERIALS AND METHODS: The 2D inversion recovery ultrashort TE sequence was evaluated in 14 healthy volunteers and 31 patients with MS. MPRAGE and T2-FLAIR images were acquired for comparison. Advanced Normalization Tools were used to correlate inversion recovery ultrashort TE, MPRAGE, and T2-FLAIR images with disability assessed by the Expanded Disability Status Scale. RESULTS: Weak correlations were observed between normal-appearing white matter volume (R = -0.03, P = .88), lesion load (R = 0.22, P = .24), and age (R = 0.14, P = .44), and disability. The MPRAGE signal in normal-appearing white matter showed a weak correlation with age (R = -0.10, P = .49) and disability (R = -0.19, P = .31). The T2-FLAIR signal in normal-appearing white matter showed a weak correlation with age (R = 0.01, P = .93) and disability (R = 0.13, P = .49). The inversion recovery ultrashort TE signal was significantly negatively correlated with age (R = -0.38, P = .009) and disability (R = -0.44; P = .01). CONCLUSIONS: Direct imaging of myelin correlates with disability in patients with MS better than indirect imaging of long-T2 water in WM using conventional clinical sequences.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/fisiopatologia , Bainha de Mielina/patologia , Adulto , Idoso , Envelhecimento/patologia , Avaliação da Deficiência , Feminino , Voluntários Saudáveis , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Substância Branca/diagnóstico por imagem
2.
Acta Neurol Scand ; 119(6): 404-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18853944

RESUMO

BACKGROUND: There is behavioural evidence that caloric vestibular stimulation (CVS) can alleviate central pain. Several such patients have also noted that it reduces tactile allodynia, an especially ill-understood phenomenon in these patients. AIMS OF THE STUDY: The first aim is to use magnetoencephalography (MEG) to study neural activity associated with tactile allodynia in central post-stroke pain (CPSP). The second is to assess how this would be affected, if at all, by CVS. The third is to assess the ability of the VESTAL solution for MEG to detect anterior cingulate activation. METHODS: A 58-year-old woman with CPSP, and marked unilateral tactile allodynia, participated in a MEG study with imaging pre- and post-CVS. RESULTS: Tactile simulation within the patient's allodynic area resulted in contralateral activation of the primary motor and anterior cingulate cortices, which had normalized 24 h post-CVS. CONCLUSIONS: We suggest that the unexpected primary motor cortex activation in response to light touch in the allodynic area arises from inappropriate activation of a normal mechanism, which may occur when a threat to homeostasis is present, to lower motor thresholds and allow for more rapid performance of corrective actions. We propose this may be mediated by the interoceptive cortex in the dorsal posterior insula.


Assuntos
Mapeamento Encefálico , Encéfalo/fisiopatologia , Manejo da Dor , Acidente Vascular Cerebral/complicações , Vestíbulo do Labirinto/fisiologia , Temperatura Baixa , Feminino , Humanos , Magnetoencefalografia , Pessoa de Meia-Idade , Dor/etiologia , Estimulação Física/métodos , Tato/fisiologia , Vestíbulo do Labirinto/inervação
3.
J Neurol Neurosurg Psychiatry ; 79(11): 1298-301, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18550629

RESUMO

BACKGROUND: Central post-stroke pain (CPSP) is often resistant to treatment. We have previously proposed that caloric vestibular stimulation might alleviate it. METHODS: We conducted a single blind placebo controlled investigational study of caloric vestibular stimulation (CVS) in nine patients with CPSP. Participants rated their pain levels before and after the procedure on a 10 point scale. RESULTS: We found a significant immediate treatment effect of the cold water caloric stimulation with an average pain reduction of 2.58 points (SEM 0.52) for the experimental condition compared with 0.54 points (SEM 0.49) for the placebo conditions. CONCLUSIONS: Participants who responded best to CVS had suffered strokes that spared and permitted activation of the dominant parieto-insular vestibular cortex (PIVC), which is known to be located in the non-dominant hemisphere. These findings tie in closely with the thermosensory disinhibition hypothesis for central pain, which leads us to propose that vestibular stimulation may alleviate CPSP from cross activation between the PIVC and the thermosensory cortex in the adjacent dorsal posterior insula. Alternatively, if one views vestibular function and thermoregulation as part of a larger interoceptive system that exists to maintain homeostasis, then it is possible they share a common integrative mechanism in the brainstem, which may act to reset the balance in central pain.


Assuntos
Manejo da Dor , Dor/etiologia , Estimulação Física/métodos , Acidente Vascular Cerebral/complicações , Sensação Térmica/fisiologia , Vestíbulo do Labirinto/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Testes Calóricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor/diagnóstico , Medição da Dor , Índice de Gravidade de Doença
4.
Am J Psychiatry ; 133(7): 827-30, 1976 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-937575

RESUMO

The authors explain why marital disharmony when one spouse has a primary affective disorder is difficult to treat but suggest that such couples can be treated successfully if the therapist is flexible and sets realistic goals. Because of the variability of the disease and the many unsubstantiated etiologies associated with it, the authors recommend a modified general system theory approach to treatment that includes a combination of psychotherapy and somatotherapy.


Assuntos
Transtorno Bipolar/terapia , Terapia Conjugal/métodos , Feminino , Humanos , Relações Interpessoais , Masculino , Teoria Psicológica , Psicopatologia
5.
Arch Neurol ; 55(4): 547-53, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9561984

RESUMO

OBJECTIVE: To provide the first comprehensive magnetic resonance imaging (MRI) assessment of brain in a series of patients with Lesch-Nyhan syndrome (LNS), with emphasis on basal ganglia measurements. DESIGN: Routine readings of MRI studies, repeated reading in random order blinded to subject diagnosis, and 3-dimensional volumetric measures of basal ganglia regions. SETTING: The Johns Hopkins Hospital, Baltimore, Md. PATIENTS: Seven patients with LNS who have hypoxanthine guanine phosphoribosyltransferase levels less than 1.6% and characteristic clinical features of the disorder, which include hyperuricemia, cognitive impairment, and dystonic movement disorder, were compared with 7 age-matched control subjects. Five of the 7 patients demonstrated self-injurious behavior. MRI studies were performed using general anesthesia because of the severity of the movement disorder. MAIN OUTCOME MEASURES: Measurement of brain regions from MRI-obtained images. RESULTS: Routine readings described mild cerebral atrophy in 2 of 7 patients, but no caudate or putamen abnormalities were reported. However, on the directed blinded rereading, small caudates were suspected in 5 of 7 cases, and abnormalities in cerebral size and cranium were identified. Volumetric studies of the patients with LNS confirmed a 34% decrease in caudate volume (P<.001), a 17% decrease in total cerebral volume (P<.03), and a 12% decrease in putamen volume (P=.19). CONCLUSIONS: To our knowledge, this is the first demonstration of consistent neuroanatomic abnormalities in LNS. The findings of reduced basal ganglia volume are consistent with the dystonic movement disorder.


Assuntos
Gânglios da Base/patologia , Encéfalo/patologia , Síndrome de Lesch-Nyhan/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Atrofia , Núcleo Caudado/patologia , Feminino , Humanos , Masculino , Putamen/patologia , Método Simples-Cego
6.
Pediatrics ; 104(3 Pt 1): 405-18, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10469763

RESUMO

BACKGROUND: One-third of children diagnosed with autism spectrum disorders (ASDs) are reported to have had normal early development followed by an autistic regression between the ages of 2 and 3 years. This clinical profile partly parallels that seen in Landau-Kleffner syndrome (LKS), an acquired language disorder (aphasia) believed to be caused by epileptiform activity. Given the additional observation that one-third of autistic children experience one or more seizures by adolescence, epileptiform activity may play a causal role in some cases of autism. OBJECTIVE: To compare and contrast patterns of epileptiform activity in children with autistic regressions versus classic LKS to determine if there is neurobiological overlap between these conditions. It was hypothesized that many children with regressive ASDs would show epileptiform activity in a multifocal pattern that includes the same brain regions implicated in LKS. DESIGN: Magnetoencephalography (MEG), a noninvasive method for identifying zones of abnormal brain electrophysiology, was used to evaluate patterns of epileptiform activity during stage III sleep in 6 children with classic LKS and 50 children with regressive ASDs with onset between 20 and 36 months of age (16 with autism and 34 with pervasive developmental disorder-not otherwise specified). Whereas 5 of the 6 children with LKS had been previously diagnosed with complex-partial seizures, a clinical seizure disorder had been diagnosed for only 15 of the 50 ASD children. However, all the children in this study had been reported to occasionally demonstrate unusual behaviors (eg, rapid blinking, holding of the hands to the ears, unprovoked crying episodes, and/or brief staring spells) which, if exhibited by a normal child, might be interpreted as indicative of a subclinical epileptiform condition. MEG data were compared with simultaneously recorded electroencephalography (EEG) data, and with data from previous 1-hour and/or 24-hour clinical EEG, when available. Multiple-dipole, spatiotemporal modeling was used to identify sites of origin and propagation for epileptiform transients. RESULTS: The MEG of all children with LKS showed primary or secondary epileptiform involvement of the left intra/perisylvian region, with all but 1 child showing additional involvement of the right sylvian region. In all cases of LKS, independent epileptiform activity beyond the sylvian region was absent, although propagation of activity to frontal or parietal regions was seen occasionally. MEG identified epileptiform activity in 41 of the 50 (82%) children with ASDs. In contrast, simultaneous EEG revealed epileptiform activity in only 68%. When epileptiform activity was present in the ASDs, the same intra/perisylvian regions seen to be epileptiform in LKS were active in 85% of the cases. Whereas primary activity outside of the sylvian regions was not seen for any of the children with LKS, 75% of the ASD children with epileptiform activity demonstrated additional nonsylvian zones of independent epileptiform activity. Despite the multifocal nature of the epileptiform activity in the ASDs, neurosurgical intervention aimed at control has lead to a reduction of autistic features and improvement in language skills in 12 of 18 cases. CONCLUSIONS: This study demonstrates that there is a subset of children with ASDs who demonstrate clinically relevant epileptiform activity during slow-wave sleep, and that this activity may be present even in the absence of a clinical seizure disorder. MEG showed significantly greater sensitivity to this epileptiform activity than simultaneous EEG, 1-hour clinical EEG, and 24-hour clinical EEG. The multifocal epileptiform pattern identified by MEG in the ASDs typically includes the same perisylvian brain regions identified as abnormal in LKS. When epileptiform activity is present in the ASDs, therapeutic strategies (antiepileptic drugs, steroids, and even neurosurgery) aimed at its control can lead to a significa


Assuntos
Transtorno Autístico/diagnóstico , Encéfalo/fisiopatologia , Epilepsia/diagnóstico , Síndrome de Landau-Kleffner/diagnóstico , Magnetoencefalografia , Transtorno Autístico/fisiopatologia , Criança , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Pré-Escolar , Eletroencefalografia , Epilepsia/fisiopatologia , Feminino , Humanos , Síndrome de Landau-Kleffner/fisiopatologia , Masculino , Sono/fisiologia
7.
Am J Med Genet ; 85(1): 53-65, 1999 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-10377013

RESUMO

We previously discovered a novel missense mutation (Lys650Met) in the tyrosine kinase domain of the fibroblast growth factor receptor 3 (FGFR3) gene in four unrelated individuals with a condition we called "severe achondroplasia with developmental delay and acanthosis nigricans" (SADDAN) [Tavormina et al., 1999: Am. J. Hum. Genet. 64:722-731]. Here we present a more detailed clinical account of the SADDAN phenotype. The FGFR3 Lys650Met mutation results in severe disturbances in endochondral bone growth that approach and overlap those observed in thanatophoric dysplasia, type I. However, this mutation is most often compatible with survival into adulthood. Other unusual bone deformities, such as femoral bowing with reverse (i.e., posterior apex) tibial and fibular bowing and "ram's horn" bowing of the clavicle, are also seen in some patients. In addition to skeletal dysplasia, progressive acanthosis nigricans, and central nervous system structural anomalies, seizures and severe developmental delays are observed in surviving SADDAN patients. Despite its location within the same FGFR3 codon as the thanatophoric dysplasia type II mutation (Lys650Glu) and a similar effect on constitutive activation of the FGFR3 tyrosine kinase, the Lys650Met is not associated with cloverleaf skull or craniosynostosis.


Assuntos
Acantose Nigricans/genética , Deficiências do Desenvolvimento/genética , Osteocondrodisplasias/genética , Mutação Puntual , Proteínas Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/genética , Feminino , Humanos , Recém-Nascido , Lisina/genética , Masculino , Metionina/genética , Fenótipo , Radiografia , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos , Crânio/diagnóstico por imagem , Crânio/patologia
8.
Clin Neurophysiol ; 115(4): 820-33, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15003762

RESUMO

OBJECTIVE: Hemiparesis due to damage by stroke in primary motor cortex (MI) or its underlying projections presents a problem for functional neuroimaging technologies that attempt to evaluate the neurophysiological basis for restoration of motor function. Traditional assessments of MI function require patients to move their fingers, hands, or limbs, which can be either impossible or markedly compromised after stroke. We recently demonstrated in normal subjects that magnetoencephalography (MEG), a non-invasive neuromagnetic functional imaging technique, detects neuronal response elicited by electrical median nerve stimulation in MI, as well as primary somatosensory cortex (SI). In the present study, we used the MEG response from median nerve stimulation to investigate the recovery of primary motor and somatosensory in acute ischemic stroke patients. METHODS: Twelve patients with unilateral ischemic strokes that affected sensorimotor functions of their hand were studied in the acute stage (4.4+/-1.2 days, mean+/-SD) and during a 1-month follow-up (38.6+/-5.6 days, except for one patient's follow-up done 6 month after stroke). RESULTS: Among the multiple cortical sources localized after median nerve stimulation, one source localized to SI and another localized to the vicinity of MI. Changes in the source strengths of the first component post-stimulus of MI and SI correlated with the extent of recovery of sensorimotor functions as determined by neurological exams. CONCLUSIONS: This study provides a novel way of indirectly assessing MI function using MEG during the acute stroke phase, when many patients often cannot perform motor tasks due to paralysis.


Assuntos
Magnetoencefalografia , Nervo Mediano/fisiologia , Neurônios Motores/fisiologia , Neurônios Aferentes/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Dedos/inervação , Dedos/fisiologia , Humanos , Masculino , Nervo Mediano/citologia , Pessoa de Meia-Idade , Tempo de Reação/fisiologia
9.
Clin Neurophysiol ; 114(5): 835-50, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12738429

RESUMO

OBJECTIVE: An integrated analysis using Electroencephalography (EEG) and magnetoencephalography (MEG) is introduced to study abnormalities in early cortical responses to auditory stimuli in schizophrenia. METHODS: Auditory responses were recorded simultaneously using EEG and MEG from 20 patients with schizophrenia and 19 control subjects. Bilateral superior temporal gyrus (STG) sources and their time courses were obtained using MEG for the 30-100 ms post-stimulus interval. The MEG STG source time courses were used to predict the EEG signal at electrode Cz. RESULTS: In control subjects, the STG sources predicted the EEG Cz recording very well (97% variance explained). In schizophrenia patients, the STG sources accounted for substantially (86%) and significantly (P<0.0002) less variance. After MEG-derived STG activity was removed from the EEG Cz signal, the residual signal was dominated by 40 Hz activity, an indication that the remaining variance in EEG is probably contributed by other brain generators, rather than by random noise. CONCLUSIONS: Integrated MEG and EEG analysis can differentiate patients and controls, and suggests a basis for a well established abnormality in the cortical auditory response in schizophrenia, implicating a disorder of functional connectivity in the relationship between STG sources and other brain generators.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados Auditivos/fisiologia , Magnetoencefalografia/métodos , Esquizofrenia/fisiopatologia , Lobo Temporal/fisiologia , Estimulação Acústica/métodos , Adulto , Feminino , Previsões , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Pacientes/estatística & dados numéricos
10.
AJNR Am J Neuroradiol ; 17(4): 705-11, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8730191

RESUMO

PURPOSE: To compare a three-dimensional Fourier transform (3DFT) gradient-echo pulse sequence with magnetization transfer at a short echo time against standard 3DFT gradient-echo technique in the evaluation of cervical spondylosis, specifically addressing the effects of motion and susceptibility artifacts on the dimensions of the neural foramina and contrast at the cerebrospinal fluid (CSF)-spinal cord interface. METHODS: Ten patients with clinically suspected cervical spondylosis were examined with axial MR imaging using both our standard 3DFT gradient-echo sequence and a 3DFT gradient-echo sequence with a short echo time plus magnetization transfer. Two neuroradiologists measured the transverse dimensions of 22 diseased neural foramina and graded the contrast at the CSF-spinal cord interface. RESULTS: Sixteen of 22 affected neural foramina were larger in the transverse dimension when the magnetization transfer technique was used than when the standard 3DFT gradient-echo sequence was used. In 9 of 10 patients superior contrast was seen at the CSF-spinal cord interface on images obtained with the magnetization transfer technique. CONCLUSIONS: In the cervical spine, 3DFT gradient-echo imaging with magnetization transfer improves contrast and sharpness of the CSF-spinal cord interface at short echo times. This results in less exaggeration of the neural foraminal stenosis as compared with that seen with standard 3DFT gradient-echo techniques owing to the diminished effects of motion and susceptibility artifacts.


Assuntos
Vértebras Cervicais , Processamento de Imagem Assistida por Computador/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Osteofitose Vertebral/diagnóstico , Líquido Cefalorraquidiano , Vértebras Cervicais/patologia , Análise de Fourier , Humanos , Aumento da Imagem/instrumentação , Medula Espinal/patologia , Compressão da Medula Espinal/diagnóstico , Estenose Espinal/diagnóstico
11.
AJNR Am J Neuroradiol ; 19(1): 83-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9432162

RESUMO

PURPOSE: Our goal was to describe the MR imaging appearance and clinical pathologic correlates of bilateral basal ganglia hyperintensity in acquired immunodeficiency syndrome (AIDS). METHODS: Medical records and laboratory data were reviewed retrospectively in nine cases of bilateral basal ganglia hyperintensity on long-repetition-time MR images. Opportunistic infections of the central nervous system were excluded by clinical and laboratory data. Postmortem neuropathologic examination was obtained in two cases. RESULTS: All patients presented acutely with new seizures or changes in mental status. A history of drug abuse was elicited in seven of the nine remaining patients. Renal failure was present in six cases. Symmetric bilateral caudate and putamen hyperintensity on T2-weighted images was found in all cases with variable extension to the surrounding white matter, thalamus, and brain stem. Postmortem neuropathologic examination in two cases revealed numerous microinfarcts in a distribution similar to the MR signal abnormalities. CONCLUSION: The MR appearance of basal ganglia hyperintensity in this series of AIDS patients represents ischemic tissue injury. We propose that this clinicopathologic entity is precipitated by the combined effects of human immunodeficiency virus infection and drug use, particularly cocaine and/or associated toxic contaminants.


Assuntos
Complexo AIDS Demência/diagnóstico , Gânglios da Base/patologia , Imageamento por Ressonância Magnética , Complexo AIDS Demência/patologia , Adulto , Cocaína , Feminino , Humanos , Masculino , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias
12.
J Neurosurg ; 93(6): 981-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11117871

RESUMO

OBJECT: Although cavernous malformations (CMs) are not detected in angiographic studies, they have a characteristic appearance on magnetic resonance (MR) images. A number of reports published in the last decade have focused on the behavior of these lesions within the clinical environment. However, little has been published about the evolution of CMs over time, as observed in imaging studies. To understand imaging-documented changes in CMs over time, we analyzed MR images of 114 cavernous malformations in 68 patients who were followed prospectively. METHODS: For each CM the location, volume, and MR imaging signal characteristics were recorded. Volume data were available for 107 lesions from initial images. The mean volume of these 107 CMs was 2779 mm3. The lesions ranged in size from 0.5 to 46,533 mm3 (46.5 cm3). Volume data from a second set of images were available for 76 CMs (mean interval from first imaging session 26 months), and from a third set of images for 24 lesions (mean interval from second imaging session 18 months). Over the first follow-up interval, the mean volume change was -991 mm3 (a decrease of approximately 1 cm3) and over the second interval the mean volume change was -642 mm3. Although these mean volume changes appear modest, volume changes in single lesions during follow-up intervals were more dramatic, with decreases as large as 45,629 mm3 (45.6 cm3) and increases as large as 6,074 mm3 (6 cm3). Serial examinations of the MR imaging signal characteristics of these CMs demonstrate a trend for maturation of blood products from a subacute, to a mixed, and finally to a chronic appearance. Three lesions appeared de novo during the follow-up period. CONCLUSIONS: On the basis of their analysis, the authors conclude that CMs exhibit a range of dynamic behaviors including enlargement, regression, and de novo formation, as well as progression through a series of characteristic MR imaging appearances.


Assuntos
Neoplasias Encefálicas/diagnóstico , Hemangioma Cavernoso/diagnóstico , Malformações Arteriovenosas Intracranianas/diagnóstico , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Criança , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Remissão Espontânea
13.
J Neurosurg ; 92(1): 79-90, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10616086

RESUMO

OBJECT: The availability of large-array biomagnetometers has led to advances in magnetoencephalography that permit scientists and clinicians to map selected brain functions onto magnetic resonance images. This merging of technologies is termed magnetic source (MS) imaging. The present study was undertaken to assess the role of MS imaging for the guidance of presurgical planning and intraoperative neurosurgical technique used in patients with intracranial mass lesions. METHODS: Twenty-six patients with intracranial mass lesions underwent a medical evaluation consisting of MS imaging, a clinical history, a neurological examination, and assessment with the Karnofsky Performance Scale. Magnetic source imaging was used to locate the somatosensory cortex in 25 patients, the visual cortex in six, and the auditory cortex in four. The distance between the lesion and the functional cortex was determined for each patient. Twenty-one patients underwent a neurosurgical procedure. As a surgical adjunct, a frameless stereotactic navigational system was used in 17 cases and a standard stereotactic apparatus in four cases. Because of the results of their MS imaging examination, two patients were not offered surgery, four underwent a stereotactic biopsy procedure, 10 were treated with a subtotal surgical resection, and seven were treated with complete surgical resection. One patient deteriorated before a procedure could be scheduled and, therefore, was not offered surgery, and two patients were offered surgery but declined. Three patients experienced surgery-related complications. CONCLUSIONS: Magnetic source imaging is an important noninvasive neurodiagnostic tool that provides critical information regarding the spatial relationship of a brain lesion to functional cortex. By providing this information, MS imaging facilitates a minimum-risk management strategy and helps guide operative neurosurgical technique in patients with intracranial mass lesions.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Encéfalo/fisiopatologia , Encéfalo/cirurgia , Imageamento por Ressonância Magnética , Magnetoencefalografia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Criança , Tomada de Decisões , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Técnicas Estereotáxicas , Resultado do Tratamento
14.
Spine (Phila Pa 1976) ; 26(10): 1172-8, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11413433

RESUMO

STUDY DESIGN: Lumbar MRI of normal adults. Image analysis to measure lumbar CSF volumes at rest and during physiologic maneuvers. OBJECTIVES: 1) Validate an MRI technique to measure CSF volumes, 2) use this technique to measure the resting volume of lumbar CSF, 3) measure changes in CSF volume with physiologic maneuvers, and 4) demonstrate the anatomic basis for these volume changes. SUMMARY OF BACKGROUND DATA: Studies using radiograph and radionuclide myelography in dogs and humans in the 1960s-1980s qualitatively showed decreases in spinal CSF volume with physiologic maneuvers. Theories were proposed to explain these changes, but they could not be confirmed because only the contrast-laden CSF was visualized using these techniques. METHODS: Four adult volunteers had lumbar MRI using a fat-saturated T2-weighted three-dimensional fast spin-echo sequence. Quantitative analysis of images was used to measure lumbar CSF volume; the technique was validated using a water phantom. Lumbar CSF volume was measured 1) at rest, 2) with hyperventilation, 3) with abdominal compression, and 4) with both hyperventilation and abdominal compression. RESULTS: Resting lumbar CSF volume ranged from 28 to 42 mL. Reversible changes in lumbar CSF volume resulting from physiologic maneuvers are visualized by MR myelography and measured. The volume change (10% reduction in volume with hyperventilation, 28% with compression, and 41% with combined hyperventilation and abdominal compression) is directly visualized to be caused by engorgement of the epidural venous plexus, compressing the thecal sac. CONCLUSIONS: MRI provides a noninvasive means to measure spinal CSF volume and demonstrates the anatomic basis of physiologic volume changes. This has important implications for spinal anesthesia.


Assuntos
Líquido Cefalorraquidiano/metabolismo , Imageamento por Ressonância Magnética/métodos , Abdome , Adulto , Feminino , Humanos , Hiperventilação/metabolismo , Vértebras Lombares , Masculino , Pressão , Medula Espinal/anatomia & histologia , Medula Espinal/metabolismo
15.
J Neurosurg Anesthesiol ; 12(3): 217-20, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10905569

RESUMO

We report a case of a 35-year-old man with achondroplasia who previously had thoracolumbar decompressive laminectomies, who developed recurrence of spinal stenosis at the thoracolumbar junction. The patient underwent standard repeat thoracolumbar decompression, removal of a disc, and spinal fusion with instrumentation in the prone position. Postoperatively the patient was confused. Computed tomography (CT) revealed hemorrhages in both cerebellar hemispheres with surrounding edema and mild mass effect. These were interpreted as venous hemorrhages. Conservative therapy was successful. This is the first case report of perioperative venous intracranial hemorrhage in the context of spinal surgery for achondroplasia. Distinctive anatomic characteristics of achondroplasia, combined with several potentially modifiable aspects of his management, may have predisposed the patient to this complication.


Assuntos
Acondroplasia/complicações , Hemorragias Intracranianas/etiologia , Complicações Intraoperatórias , Compressão da Medula Espinal/cirurgia , Adulto , Edema Encefálico , Confusão , Descompressão Cirúrgica , Contagem de Eritrócitos , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Hematoma/terapia , Humanos , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/terapia , Laminectomia , Masculino , Tempo de Tromboplastina Parcial , Contagem de Plaquetas , Compressão da Medula Espinal/etiologia , Tomografia Computadorizada por Raios X
16.
Clin Neurol Neurosurg ; 99 Suppl 2: S26-30, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9409400

RESUMO

The epidemiology and radiological features of Moyamoya disease (MMD) in the US were investigated. This study encompassed 98 cases; 26 were newly collected from eight US institutions and 72 were previously reported in the US literature. The patients ranged in age from 6 months to 67 years with age peaks in the first, third and fourth decades. MMD was seen in various ethnic groups and females were more commonly involved (71%) than males. A specific etiology could not be determined in most cases but arteriosclerosis and use of oral contraceptives were occasional associations. On angiography and/or magnetic resonance angiography (MRA), carotid arterial stenosis or occlusion was seen bilaterally in 95 cases (97%) and unilaterally in three. On MR or MRA, internal carotid steno-occlusive lesions were well demonstrated in all cases but Moyamoya collateral vessels (MMVs) were visualized in only 65% of the patients. MMVs in the basal ganglia and thalami were best demonstrated on T1 weighted images. Parenchymal lesions were seen in all patients and were often bilateral. With advances in MR techniques and increasing awareness of diagnostic guidelines, MMD will be diagnosed more frequently than before in the US.


Assuntos
Doença de Moyamoya/epidemiologia , Adolescente , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Angiografia Cerebral , Criança , Pré-Escolar , Feminino , Gadolínio , Humanos , Incidência , Lactente , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico , Estados Unidos/epidemiologia
17.
Magn Reson Imaging Clin N Am ; 8(3): 529-40, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947925

RESUMO

MR imaging is the modality of choice for intradural spinal tumors because of its unsurpassed depiction of soft tissues, the use of intravenous contrast, the absence of beam-hardening artifacts, and the ability to image in multiple planes. Intradural tumors are classified as intradural-extramedullary and intradural-intramedullary. MR imaging techniques that best depict these tumors are reviewed, and several examples of tumors are described and illustrated.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias da Medula Espinal/diagnóstico , Vértebras Cervicais , Meios de Contraste , Glioma/diagnóstico , Hemangioblastoma/diagnóstico , Humanos , Neoplasias Meníngeas/diagnóstico , Neoplasias Embrionárias de Células Germinativas/diagnóstico , Neoplasias de Bainha Neural/diagnóstico
18.
Int J Oral Maxillofac Implants ; 10(4): 415-20, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7672842

RESUMO

This report compares the conventional and delay methods of implantation, evaluating the bone formation around a dense apatite implant. In the conventional method, the implant is placed immediately after the cavity is prepared. In the delay technique, the implant is placed 2 weeks after preparation. This study found that many new thin trabeculae and capillaries formed around the cavity during the delay period, while none had formed at the time of implantation using the conventional method. The delay method showed earlier and wider bone formation, and less surrounding fibrous encapsulation. These results indicate that the delay technique can be an efficient method for establishing good bone binding.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Mandíbula/cirurgia , Osseointegração , Animais , Apatitas/química , Medula Óssea/patologia , Capilares/patologia , Tecido Conjuntivo/patologia , Cães , Mandíbula/irrigação sanguínea , Mandíbula/patologia , Osteogênese , Propriedades de Superfície , Fatores de Tempo , Cicatrização
19.
Am J Psychother ; 42(3): 416-24, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3177705

RESUMO

A reverse selfobject experience occurs when an infant functions as a selfobject for the mother. While reverse selfobject experiences are a part of healthy development, excessive experiences (a) traumatize the infant, (b) contribute to a pathological grandiose self, and (c) lead to severe treatment resistance in the early stages of psychotherapy.


Assuntos
Ego , Apego ao Objeto , Feminino , Humanos , Lactente , Relações Mãe-Filho , Relações Profissional-Paciente , Psicoterapia
20.
Am J Psychother ; 53(2): 177-87, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10415987

RESUMO

Exploration of the clinical literature shows an awareness that an infant's experience as a selfobject often is traumatic, but if there is an experience of mutuality, the trauma might be avoided. Where such mutuality does not occur, an infant's experience of constantly repairing a depressed parent, or of being blamed, abused or having an identity imposed by a parent, leads to exhaustion and/or traumatization. Kohut's paradigmatic case of Mr. Z is presented as an example of the distressful effects of being a selfobject (of idealization) for a mother. Patients who were traumatized as infants by functioning as a selfobject for a parent often present for psychotherapy seeking an archaic form of twinship that recreates the infant-parent traumatizing relationship by imposing on the therapist the function that had been imposed on them as infants. Until this archaic twinship is empathically understood, accepted and explored with the patient, the lasting effects of the traumatization are not resolved.


Assuntos
Ego , Apego ao Objeto , Adulto , Feminino , Humanos , Lactente , Masculino , Relações Pais-Filho , Terapia Psicanalítica , Psicologia da Criança , Transferência Psicológica
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