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<p><b>BACKGROUND</b>HIV is a neurotropic virus which can cause brain white matter demyelination, gliosis, and other pathological changes that appear as HIV encephalitis or AIDS dementia. The purpose of this study was to investigate the change of the diffused condition of water molecules in brain white matter in early acquired immune deficiency syndrome (AIDS) patients using MR diffusion tensor imaging (DTI).</p><p><b>METHODS</b>DTI examinations were performed on a Siemens 3.0T MR scanner in 23 AIDS patients with normal brain appearance by conventional MRI and 20 healthy volunteers as the control group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured in nine regions; corpus callosum (CC) knee, CC body, CC splenium, periventricular white matter, frontal lobe white matter, parietal lobe white matter, occipital lobe white matter, and the anterior and posterior limbs of the internal capsule. The mean FA and ADC values from each region were compared in three groups: the symptomatic, asymptomatic and the control.</p><p><b>RESULTS</b>The mean FA values were significantly lower and the mean ADC values were significantly higher in all nine regions in patients in the symptomatic group than in the asymptomatic and control group patients. In the asymptomatic group, the mean FA values were significantly lower and the mean ADC values were significantly higher at the CC knee, CC body, CC splenium, periventricular white matter, frontal lobe white matter and parietal lobe white matter, than in the control group. There were no significant differences at other regions between the two groups.</p><p><b>CONCLUSIONS</b>The diffused changes of water molecules in brain white matter in AIDS patients are related to brain white matter regions. DTI examination can detect the brain white matter lesions early in AIDS patients.</p>
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Adolescent , Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Syndrome d'immunodéficience acquise , Anatomopathologie , Encéphale , Anatomopathologie , Imagerie par tenseur de diffusion , MéthodesRésumé
<p><b>OBJECTIVE</b>To study the feasibility of endolymphatic visualization and the diagnosis of Meniere's disease by applying intratympanic gadolinium administration through the tympanic membrance and three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging (3D-FLAIR MRI). To study the relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests, such as pure tone audiometry (PTA), electrocochleography (EcoG), caloric test and vestibular evoked myogenic potential (VEMP).</p><p><b>METHODS</b>With a three Tesla magnetic resonance imaging (MRI) unit, 3D-FLAIR imaging was performed 24 hours after intratympanic gadolinium through the tympanic membrance in 32 patients with clinically diagnosed unilateral Meniere's Disease. We visualized the enhanced imaging of perilymphatic space in bilateral cochlea, vestibular and (or) canal, scoring scala tympani and scala vestibule of bilateral cochlear basal turn respectively and measuring the developing area of bilateral vestibule and the signal intensity ratio (SIR) between the vestibule and the brain stem subjectively. PTA, EcoG, caloric test and VEMP were performed. The relationship between the endolymphatic hydrops visualized by MRI and audio-vestibular functional tests were studied.</p><p><b>RESULTS</b>The gadolinium appeared in almost all parts of the perilymph in cochlea, vestibular and (or) canals in all 32 patients' inner ears, so the endolymphatic space was clearly shown on 3D-FLAIR imaging. The scala vestibuli score value between the affected side and the healthy side were statistically significant (Z = 4.309, P < 0.05) . The developing vestibular area between the affected side and the healthy side [(6.04 ± 2.89) mm(2), (8.28 ± 3.04)mm(2)] were statistically significant (t = 3.322, P < 0.05) . Abnormal vestibular evoked myogenic potentials were significantly correlated with the developing vestibular area of the affected side (F = 11.96, P < 0.05) . Abnormal electrocochleography were significantly correlated with scala vestibuli score value of cochlear basal turn in the affected side (Z = 3.17, P < 0.05) . No significant correlation was found between the scala vestibuli score value or the developing vestibular area and caloric test or PTA findings.</p><p><b>CONCLUSIONS</b>3D-FLAIR MRI with intratympanic gadolinium injection through the tympanic membrance can discriminate the border between the perilymph and the endolymph and show endolymphatic hydrops. This method may provide radiographic reference for the diagnosis of Meniere's disease. The results of VEMP and electrocochleography might have appropriate correlation with degree of vestibular and cochlear hydrops.</p>
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Humains , Audiométrie électroencéphalographique , Audiométrie tonale , Épreuves vestibulaires caloriques , Cochlée , Produits de contraste , Oreille interne , Endolymphe , Hydrops endolymphatique , Diagnostic , Acide gadopentétique , Imagerie tridimensionnelle , Injections , Imagerie par résonance magnétique , Maladie de Ménière , Périlymphe , Potentiels évoqués vestibulaires myogéniques , Labyrinthe vestibulaireRésumé
<p><b>OBJECTIVE</b>To evaluate the preoperative pain degree of lumbar intervertebral disc herniation and analyzed its reason.</p><p><b>METHODS</b>From January 2002 to December 2008,265 patients with lumbar intervertebral disc herniation were operated by single segment, of which site in L4,5 was 128 cases and in L5S1 was 137 cases. There were 162 males and 103 female, ranging in age from 21 to 78 years, with an average of 46.3 years. Oswestry index of all patients was observed before operation. The patients were divided into five groups based on Carragee system (according to degree of nucleus pulposus herniation and degree of fibrous ring cleavage to group, prolapse and liberation of nucleus pulposus with small ring cleavage was group I; prolapse and liberation with large ring cleavage was group II; contained fragment with integrated fibrous ring was group III; no contained fragment with integrated fibrous ring was group IV; calcified nucleus pulposus with degenerative fibrous ring was group V). The associativity between five types of lumbar intervertebral disc herniation and preoperative pain degree was analyzed.</p><p><b>RESULTS</b>The preoperative pain in group I and group II was more severe than that of other groups (P<0.01). The preoperative pain in group II was more severe than that of group I (P<0.01).</p><p><b>CONCLUSION</b>Nucleus pulposus can migrated into the spinal canal and will aggravate the nerve root pain if lumbar intervertebral disc herniation accompanies with fibrous ring cleavage; and freed materials can aggravate the nerve root pain by the chemical factor.</p>
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Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Déplacement de disque intervertébral , Chirurgie générale , Vertèbres lombales , Chirurgie générale , Douleur , Période préopératoire , Résultat thérapeutiqueRésumé
Objective To evaluate the diagnostic values of diffusion weighted MRI(DWI)and contrast-enhanced magnetic resonance imaging(CE-MRI)using gadolinium chelates in patients with brain abscesses.Methods Conventional TlWI,T2WI,fluid attenuated inversion recovery(FLAIR),DWI and gadolinium-enhanced MRI were performed in 49 patients with single cystic/solid brain lesions.Retrospective analysis of the DWI signals and enhancement characteristics of patients with brain abscesses(n=22)and with cystic/necrotic brain tumors(n=27)was performed; meanwhile,measurement of the ADC values of the necrotic areas was performed.DWI combined with conventional sequences (group Ⅰ),CE-MRI combined with conventional sequences(group Ⅱ),and DWI,CE-MRI and conventional sequences(group Ⅲ)were employed to calculate their sensitivity,specificity,positive predictive value,negative predictive value and accuracy; these results were compared with the pathological results.Results The high DWI signal was noted in 20 patients with brain abscesses,and low DWI signal in 24 patients with cystic/necrotic brain tumors.Evenly thin walls and a ring enhancement under enhanced scan were noted in 14 patients with abscesses and 12 patients with cystic/necrotic brain tumors.Most of the ADC values in patients with brain abscesses were significantly lower than those in patients with cystic/necrotic brain tumors(P<0.05).The diagnostic sensitivity to brain abscess in group I,group Ⅱ and group Ⅲ were 90.9%,63.6% and 95.5%,respectively; the difference was statistically significant between group Ⅰ and group Ⅱ(P<0.05),and between group Ⅱ and group Ⅲ(P<0.05),but not between group Ⅰ and group Ⅲ(P>0.05).Conclusion DWI is more sensitive in detecting the brain abscess than CE-MRI,and the measurement of ADC values can provide valuable differential diagnostic information for patients with brain abscess and cystic/necrotic brain tumor.
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<p><b>OBJECTIVE</b>To explore the functional brain localization with magnetic resonance imaging (MRI) after acupuncturing the Yuan-Source and He-Sea acupoints of Stomach Meridian of Foot-Yangming (ST).</p><p><b>METHODS</b>The study was performed in 30 healthy volunteers who underwent acupuncture at Yuan-Source acupoint (Chongyang, ST42) and He-Sea acupoint (Zusanli, ST36) (ST group). Ten of these were also underwent acupuncture at the non-acupoints as the control group. Blood oxygenation level dependent functional MRI was performed.</p><p><b>RESULTS</b>In the ST group, signal increasing areas were demonstrated in bilateral superior temporal gyri (Broadmann 22), bilateral supramarginal gyri (Broadmann 40), bilateral cerebellar hemispheres, bilateral cingulate gyri and isthmus of cingulate gyri (Broadmann 32, 30), bilateral superior parietal lobules (Broadmann 7); signal decreasing areas were shown in bilateral orbital gyri (Broadmann 11), bilateral temporal pole (Broadmann 38), right inferior frontal gyrus (Broadmann 47) and right medial occipitotemporal gyrus (Broadmann 36). In the control group, signal increases areas were demonstrated in superior temporal gyri, precentral gyri, cingulate gyri, thalamus, insula and cerebellum. The size, signal intensity and number of increasing areas in control group are less than in ST group.</p><p><b>CONCLUSION</b>Combined acupuncture of Yuan-Source and He-Sea acupoints of ST can activate and decrease the multiple brain regions of "splanchnic brain" and thus reach a new functional balance to relieve pain.</p>
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Adulte , Femelle , Humains , Mâle , Jeune adulte , Points d'acupuncture , Encéphale , Physiologie , Électroacupuncture , Imagerie par résonance magnétique , MéridiensRésumé
<p><b>OBJECTIVE</b>To analyze effect of treatment of lumbar intervertebral disc herniation with nucleus pulposus resection through small incision and lamina fenestration,and to explore operative advantage and mattars needing attention.</p><p><b>METHODS</b>Ninety-six patients with lumbar intervertebral disc herniation, including 48 males and 48 females with an average age of 46.4 years (ranging for 16-75 years) and an average course of 5 years (ranging from 1 month to 30 years), were treated with nucleus pulposus resection through small incision and lamina fenestration. The clinical effects were analyzed according to JOA scoring criteria of lower back pain.</p><p><b>RESULTS</b>All patients were followed up from 6 months to 3.5 years with an average of 1.2 years. According to JOA scoring criteria, 34 cases obtained excellent result, 55 good, fair 7. The rate of excellent and good was 92.71% and the mean improvement rate was 54.53%.</p><p><b>CONCLUSION</b>Nucleus pulposus resection through small incision and lamina fenestration can obtain satisfactory outcome in treating lumbar intertebral disc herniation. The incidence of lumbar instability and postoperative complications were low. It is one of the better method for the treatment of lumbar intertebral disc herniation.</p>
Sujets)
Adolescent , Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Déplacement de disque intervertébral , Chirurgie générale , Vertèbres lombales , Chirurgie générale , Interventions chirurgicales mini-invasives , Résultat thérapeutiqueRésumé
<p><b>BACKGROUND</b>Evaluation of fetal central nervous system (CNS) agenesis by ultrasonography (US) is frequently limited, but magnetic resonance imaging (MRI) has its own advantages and is gaining popularity in displaying suspected fetal anomalies. The purpose of this study was to explore the value of MRI in detecting fetal CNS agenesis.</p><p><b>METHODS</b>Thirty-four women (aged from 22 to 35 years, average 27 years) with complicated pregnancies (16 - 39 weeks of gestation, average 30 weeks) were examined with a 1.5 T superconductive MR unit within 24 hours after ultrasonography. Half-Fourier acquisition single-shot turbo spin-echo (HASTE) T(2)-weighted imaging (T(2)WI) sequence were performed in all patients, and fast low angle shot (FLASH) T(1)-weighted imaging (T(1)WI) sequence were applied sequentially in seven of them. Comparison of the results was made between the MRI and US findings as well as autopsy or postnatal follow-up MRI findings.</p><p><b>RESULTS</b>The gyrus, sulcus, corpus callosum, thalamus, cerebellum, brainstem, and spinal cord of fetus were shown more clearly on T(2)-weighted MR images than on T(1)-weighted MR images. MRI corrected the diagnosis of US in 10 cases (10/34, 29.41%) and the diagnosis was missed only in 1 case (1/34, 2.94%).</p><p><b>CONCLUSION</b>MRI has advantages to US in detecting fetal CNS anomalies and is a supplement to US in complicated pregnancies.</p>
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Adulte , Femelle , Humains , Grossesse , Système nerveux central , Malformations , Imagerie diagnostique , Imagerie par résonance magnétique , Méthodes , Échographie prénataleRésumé
Objective To evaluate the role of CT and MR/in the diagnosis of posterior reversible encephalopathy syndrome(PRES).Methods Eight women with PRES(6 pregnant women,1 case after chemotherapy,and 1 patient with hypertension)were enrolled in our study.All of them had MR imaging (T_1WI,T_2WI,FLAIR,DWI),and five cases underwent post-contrast T_1WI and three dimensional contrast enhanced MR angiography(3D CEMRA).Two cases also had CT scan.Results MRV in all 8 patients showed no evidence of stenosis,dilation,or thrombosis in cranial veins and sinuses.MRI demonstrated multiple lesions located in bilateral parieto-occipital lobes(8 cases),bilateral basal ganglia(2 cases),and bilateral frontal lobes(4 cases).The lesions were prominent within white matter,some of them involved gray matter(3 cases).Lesions appeared as hyperintense signals on FLAIR and T_2-weighted images, isointense or mildly hypointense signals on T_1-weighted images,normal or decreased intensity on DWI,and isointensity or hyperintensity on apparent diffusion coefficient(ADC)maps.Post-contrast T_1WI showed mild reversible enhancement and 3D CEMFdisplayed numerous reversible“grape-like”enhancements in terminal arterial branches along the middle cerebral artery(MCA),anterior cerebral artery(ACA)and posterior cerebral artery(PCA).Follow-up scan showed decreased abnormal signals.Conclusion Lesions of PRES are usually located in parieto-occipital lobes,especially in white matter,but they can also be seen in frontal lobes and basal ganglia bilaterally.Post-contrast T_1WI and 3D enhanced MRA can provide useful information in the manifestation of reversible enhancement.MRI has advantages to display lesion in PRES,
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Objective To investigate the differences of apparent diffusion coefficient(ADC)value in normal breasts and to evaluate the correlation between ADC value and corresponding histology.Methods Sixty-two normal breasts including 42 normal breasts of 42 patients with unilateral lesions and 20 normal breasts of 10 volunteers were studied.The ADC value of all 62 normal breasts were calculated when b value was given from 1000 to 0 s/mm~2,1000 to 500 s/mm~2and 500 to 0 s/mm~2.The MRI features of 60 normal breasts were classified into 3 types(dense,lobular-speckled,degenerative types)according to Wolf's classification and histology.Results DWI and ADC images were different in 3 types of normal breasts because of different histologic structures.The mean ADC value of the dense type breasts was(1.70? 0.37)?10~(-3)mm~2/s,the lobular-speckled type was(1.93?0.46)?10~(-3)mm~2/s and the degenerative type was(1.18?0.65)?10~(-3)mm~2/s(F=12.998,P=0.000).There were no significant differences between the dense type and the lobular-speckled type(F=2.167,P=0.147),but significant differences between the dense type and the degenerative type,the lobular-speckled type and the degenerate type(F=5.593 and 19.128;P=0.029 and 0.000).When b value decreased,the ADC value of the dense type and the lobular- speckled type increased correspondingly,but the degenerative type didn't increase apparently.Conclusion ADC value was influenced by histologic structures in normal breasts and also was influenced by b value in the dense type and lobular-speckled type breasts.
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Objective To investigate the diagnostic value of internal septation for differentiating benign from malignant breast lesions.Methods A total of 26 patients were included in the study,in which 12 patients had 20 lesions of breast carcinoma and 14 patients had 25 lesions of fibroadenoma diagnosed either pathologically or clinically.The differential diagnoistic value of the hypointensive internal septation was analyzed.Results The signal intensity of fibroadenomas and malignant lesions on T_2-weighted fat- suppressed images could be classified as iso- to hyper- intensity,hypointensity and mixed intensity. According to the signal intensity classification,there were 5,11 and 4 cases in patients with breast carcinoma respectively,while 11,10,4 cases in patients with fibroadenoma respectively.There was no statistical difference in the distribution between the two patient groups(?~2=1.764,P=0.414).The shape of fibroadenomas and malignant lesions could be classified as irregular、roundish or lobulated.According to the morphological classification,there were 12,7 and 1 case in patients with breast carcinoma respectively, while 1,7,17 cases in patients with fibroadenoma respectively.There was statistical difference in the distribution between the two patient groups(?~2=23.262,P=0.000).The typical features of fibroadenomas were as follows:lobulated shape,hypointensive internal septations on T_2-weighted or postcontrast images. The diagnostic sensitivity of the three imaging features for fibroadenoma was 68%(17/25),52%(13/25), and 72%(18/25)respectively;and the diagnostic specificity was 95%(19/20),90%(18/20),95% (19/20)respectively.Conclusion The internal septation is a rather specific sign for diagnosis of fibroadenomas.