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J Capellades

Publications and source records attributed to J Capellades.

9 recordsLinked to original sources
PubMed1998

31Phosphorus magnetic resonance spectroscopy in the assessment of head and neck tumors.

PURPOSE: 31Phosphorus magnetic resonance spectroscopy (31P-MRS) provides biochemical information in a noninvasive way. The aim of this work was: (a) to characterize the 31P spectrum of advanced head and neck tumors, and (b) to evaluate the spectral changes after treatment and to correlate them with the pathologic response. METHODS AND MATERIALS: A total of 20 patients diagnosed with advanced head and neck tumors and 7 healthy controls participated in the study. The tumor mass and its contralateral side were studied by means of 31P-MRS before and after treatment. Neck muscles of a control group were also studied. RESULTS: Tumors presented ratios of phosphomonoesters (PME), phosphodiesters (PDE), and inorganic phosphate (Pi) with respect to the adenosine triphosphate (ATP), significantly higher and a PCr (phosphocreatine)/ATP ratio lower than the neck muscle of volunteers or the contralateral side. The PDE/ATP and PME/ATP ratio values obtained before therapy were similar, independent of the later response to treatment. However, when there was a complete response, the ratios measured after treatment were decreased. CONCLUSION: These results show the existence of significant differences between the 31phosphorus spectrum of tumors and neck muscle, but also between the tumors and their contralateral sides. Moreover, 31P-MRS is able to detect metabolic changes after a complete response. These results suggest that 31P-MRS would be useful in the evaluation of the clinical response of head and neck tumors.

Adenosine Triphosphate↗
PubMed1998

[Value of cranial MRI in the follow-up of dural sinus thrombosis].

INTRODUCTION: At the present time it is well established that cranial magnetic resonance (MR) is the imaging technique of choice for diagnosis of thrombosis of the dural sinuses. However, few studies have been done to evaluate its role in follow-up in this cerebrovascular disorder. OBJECTIVE: To assess the alterations in resonance signal in follow-up of patients with thrombosis of the dural sinuses and the clinical correlation of this. MATERIAL AND METHODS: We reviewed the clinical histories of 12 patients diagnosed on cranial MR as having thrombosis of the dural sinuses; 8 cases were also seen again six months later. The cranial MR study was done using a 1.5 or 1.0 T superconductive apparatus to do measured spin-echo sequences (SE) in T1 and T2 in sagittal, transverse and coronal planes. The time elapsed between diagnosis on MR and clinical diagnosis was between 24 hours and 6 months. RESULTS: All patients had stronger resonance signals in T1 and T2 indicating a subacute phase of the thrombosis (oxidative conversion of deoxyhaemoglobin to methoxyhaemoglobin) and complete absence of blood flow in the sinuses. The eight patients seen again after six months were found to be normal on neurological. On cranial MR partial recanalization was seen in 5 of these (62%). CONCLUSION: Changes in the resonance signal persist for a long time both with and without signs of recanalization. This finding does not affect the medium term clinical course.

Adult↗
PubMed1996

[Cerebral proton spectroscopy of people infected with the human immunodeficiency virus].

BACKGROUND: This article presents a combined magnetic resonance imaging and proton spectroscopy protocol (MRI/1H-MRS) applied to study the brain of human immunodeficiency virus (HIV) infected patients. The spectroscopic results were compared with clinical and radiological parameters. PATIENTS AND METHODS: The proton spectra of 57 HIV patients and 20 control subjects were obtained from a volume of interest of 8 cm3 located in the parietooccipital region of the brain that did not include any focal lesion. The resonance areas due to N-acetyl aspartate (NAA), creatine (Cr) and choline (Cho) were obtained. The MRI exam allowed us to determine the presence of focal or diffuse lesions and the degree of atrophy. Finally, the clinical exploration included the performance of a Mini-Mental test. The NAA/Cr, NAA/Cho and Cho/Cr ratios were correlated with clinical characteristics, the result of the Mini-Mental test, the presence of lesions and the degree of atrophy. RESULTS: There were altered spectral patterns in a volume of the brain that did not contain any focal lesion. The decrease in the NAA/Cr or NAA/Cho ratios was significative when considering the presence of atrophy, the existence of signs of cognitive deficiencies or the diagnosis of AIDS-dementia complex. CONCLUSIONS: The spectral changes found in the present study suggest the existence of neuronal lesions that would be due to the HIV-infection. A combined MRI/1H-MRS study may provide a more complete information about the neurological impairment by HIV and could constitute a marker of AIDS-dementia complex.

Adult↗
PubMed1996

A multicenter proton magnetic resonance spectroscopy study of neurological complications of AIDS.

Human immunodeficiency virus (HIV) infection as seen in Europe and the United States has predominantly been contracted through male homosexual sex or intravenous drug abuse. In infected subjects, the brain is frequently affected both clinically and neuropathologically. The aim of this multicenter study has been to evaluate the value of single-voxel proton magnetic resonance spectroscopy (MRS) in the assessment of the neurological complications of acquired immunodeficiency syndrome (AIDS). MRS (voxel size = 8 ml, TR/TE = 1600/135 msec) was performed in 137 HIV-1-seropositive patients and 64 healthy controls without risk factors at three clinical MR sites operating at 1.5 T. The first result of this multicenter trial is that good reproducibility of results among participating sites was found. This demonstrates the reliability and robustness of MRS in the study of in vivo brain metabolism. In HIV patients, there was no significant correlation between metabolite ratios of brain detected by MRS and CDC grouping of patients or CD4 count. In contrast, the variations of brain metabolite ratios (NA/Cr, NA/Cho, and Cho/Cr) were related to the occurrence of encephalopathy, brain atrophy, or diffuse white matter lesions. There was no significant difference in brain metabolites between male homosexual AIDS patients and male intravenous drug user AIDS patients, whatever their neurological status (neurosymptomatic or neuroasymptomatic). Thus, the mode of transmission of HIV infection does not appear to affect the cerebral changes observed in the proton spectra from AIDS patients. Because of its ease of implementation and high information content, single-voxel proton MRS is likely to play a significant role in the evaluation of HIV-related encephalopathies.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

[Eosinophilic cystitis. Apropos of a case].

We report a case of eosinophilic cystitis (EC) in an elderly patient who had previously undergone transurethral resection of a bladder tumor which is the reason why this diagnosis was not taken into consideration and was discovered by the pathologist in a fragment whose intraoperative diagnosis had been that of tumor recurrence. We describe the radiologic features of this disease entity and its similarity to other malignant conditions. Because of the foregoing, a differential diagnosis--both clinical as well as radiologic--must be made.

Aged↗