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The genetic basis of the many progressive, multi systemic, mitochondrial diseases that cause a lack of cellular ATP production is heterogeneous, with defects found both in the mitochondrial genome as well as in the nuclear genome. Many different mutations have been found in the genes encoding subunits of the enzyme complexes of the oxidative phosphorylation system. In addition, mutations in genes encoding proteins involved in the assembly of these complexes are known to cause mitochondrial disorders. Here we describe two sisters with a mitochondrial disease characterized by lesions in the medulla oblongata, as demonstrated by brain magnetic resonance imaging, and an isolated complex IV deficiency and reduced levels of individual complex IV subunits. Whole exome sequencing revealed a homozygous nonsense mutation resulting in a premature stop codon in the gene encoding Pet117, a small protein that has previously been predicted to be a complex IV assembly factor. PET117 has not been identified as a mitochondrial disease gene before. Lentiviral complementation of patient fibroblasts with wild-type PET117 restored the complex IV deficiency, proving that the gene defect is responsible for the complex IV deficiency in the patients, and indicating a pivotal role of this protein in the proper functioning of complex IV. Although previous studies had suggested a possible role of this protein in the insertion of copper into complex IV, studies in patient fibroblasts could not confirm this. This case presentation thus implicates mutations in PET117 as a novel cause of mitochondrial disease.
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Proteínas Adaptadoras Transductoras de Señales/genética , Sistema Nervioso Central/patología , Deficiencia de Citocromo-c Oxidasa/genética , Bulbo Raquídeo/patología , Mutación , Células Cultivadas , Preescolar , Femenino , Humanos , Masculino , Fosforilación Oxidativa , LinajeRESUMEN
Dural arteriovenous fistulae (DAVFs) are a rare cause of intracranial haemorrhage. We aimed to investigate outcome of patients with intracranial haemorrhage from a DAVF. We performed a systematic literature search for studies reporting outcome after intracranial haemorrhage caused by a DAVF. We used predefined selection criteria and assessed the quality of the studies. In addition, we studied outcome in all patients with DAVF who had presented with intracranial haemorrhage at two university centers in the Netherlands, between January 2007 and April 2012. We calculated case fatality and proportions of patients with poor outcome (defined as modified Rankin Scale ≥ 3 or Glasgow Outcome Scale ≤ 3) during follow-up. We investigated mean age, sex, mid-year of study and percentage of patients with parenchymal haemorrhage as determinants of case fatality and poor outcome. The literature search yielded 16 studies, all but two retrospective and all hospital-based. Combined with our cohort of 29 patients the total number of patients with DAVF-related intracranial haemorrhage was 326 (58% intracerebral haemorrhage). At a median follow-up of 12 months case fatality was 4.7% (95% CI 2.5-7.5; 17 cohorts) and the proportion of patients with poor outcome 8.3% (95% CI 3.1-15.7; nine cohorts). We found no effect of mean age, sex, mid-year of the cohorts and percentage of patients with parenchymal haemorrhage on either outcome. Hospital based case-series suggest a relatively low risk of death and poor outcome in patients with intracranial haemorrhage due to rupture of a DAVF. These risks may be underestimated because of bias.
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Malformaciones Vasculares del Sistema Nervioso Central/complicaciones , Malformaciones Vasculares del Sistema Nervioso Central/mortalidad , Hemorragias Intracraneales/etiología , Hemorragias Intracraneales/mortalidad , Evaluación de Resultado en la Atención de Salud , Malformaciones Vasculares del Sistema Nervioso Central/terapia , Estudios de Seguimiento , Humanos , Hemorragias Intracraneales/terapia , Persona de Mediana EdadRESUMEN
BACKGROUND: In genome-wide association studies (GWAS) five putative risk loci are associated with intracranial aneurysm. As brain arteriovenous malformations (AVM) and intracranial aneurysms are both intracranial vascular diseases and AVMs often have associated aneurysms, we investigated whether these loci are also associated with sporadic brain AVM. METHODS: We included 506 patients (168 Dutch, 338 American) and 1548 controls, all Caucasians. Controls had been recruited as part of previous GWAS. Dutch patients were genotyped by KASPar assay and US patients by Affymetrix SNP 6.0 array. Associations in each cohort were tested by univariable logistic regression modelling, with subgroup analysis in 205 American cases with aneurysm data. Meta-analysis was performed by a Mantel-Haenszel fixed-effect method. RESULTS: In the Dutch cohort none of the single nucleotide polymorphisms (SNPs) were associated with AVMs. In the American cohort, genotyped SNPs near SOX-17 (OR 0.74; 95% CI 0.56-0.98), RBBP8 (OR 0.76; 95% CI 0.62-0.94) and an imputed SNP near CDKN2B-AS1 (OR 0.79; 95% CI 0.64-0.98) were significantly associated with AVM. The association with SNPs near SOX-17 and CDKN2B-AS1 but not RBBP8 were strongest in patients with AVM with associated aneurysms. In the meta-analysis we found no significant associations between allele frequencies and AVM occurrence, but rs9298506, near SOX-17 approached statistical significance (OR 0.77; 95% CI 0.57-1.03, p=0.08). CONCLUSIONS: Our meta-analysis of two Caucasian cohorts did not show an association between five aneurysm-associated loci and sporadic brain AVM. Possible involvement of SOX-17 and RBBP8, genes involved in cell cycle progression, deserves further investigation.
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Predisposición Genética a la Enfermedad/genética , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/genética , Malformaciones Arteriovenosas Intracraneales/complicaciones , Malformaciones Arteriovenosas Intracraneales/genética , Proteínas Portadoras/genética , Estudios de Casos y Controles , Proteínas de Transporte de Catión , Ciclinas/genética , Endodesoxirribonucleasas , Proteínas Activadoras de GTPasa , Frecuencia de los Genes/genética , Estudio de Asociación del Genoma Completo , Humanos , Proteínas Nucleares/genética , Polimorfismo de Nucleótido Simple , ARN Largo no Codificante/genética , Factores de Transcripción SOXF/genética , Proteínas Supresoras de Tumor/genética , Población Blanca/genéticaRESUMEN
BACKGROUND AND PURPOSE: Invasive cerebral DSA has largely been replaced by CTA, which is noninvasive but has a compromised arterial view due to superimposed bone and veins. The purpose of this study was to evaluate whether arterial visualization in CTPa is superior to standard CTA, which would eliminate the need for an additional CTA scan to assess arterial diseases and therefore reduce radiation dose. MATERIALS AND METHODS: In this study, we included 24 patients with subarachnoid hemorrhage for whom CTA and CTP were available. Arterial quality and presence of superimposed veins and bone in CTPa were compared with CTA and scored by 2 radiologists by using a VAS (0%-100%). Average VAS scores were determined and VAS scores per patient were converted to a 10-point NRS. Arterial visualization was considered to be improved when the highest rate (NRS 10, VAS > 90%) was scored for arterial quality, and the lowest rate (NRS 1, VAS < 10%), for the presence of superimposed veins and bone. A sign test with continuity correction was used to test whether the number of cases with these rates was significant. RESULTS: Average VAS scores in the proximal area were 94% (arterial quality), 4% (presence of bone), and 7% (presence of veins). In this area, the sign test showed that a significant number of cases scored NRS 10 for arterial quality (P < .02) and NRS 1 for the presence of superimposed veins and bone (P < .01). CONCLUSIONS: Cerebral CTPa shows improved arterial visualization in the proximal area compared with CTA, with similar arterial quality but no superimposed bone and veins.
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Angiografía Cerebral/métodos , Arterias Cerebrales/diagnóstico por imagen , Imagen de Perfusión/métodos , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Hemorragia Subaracnoidea/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
The purpose of this study was to evaluate the contribution of posterior circulation to memory function by comparing memory scores between patients with and without a foetal-type posterior cerebral artery (FTP) during the intracarotid amobarbital procedure (IAP) in epilepsy patients. Patients undergoing bilateral IAP between January 2004 and January 2010 were retrospectively included. Pre-test angiograms were assessed for the presence of a FTP. Memory function scores (% correct) after right and left injections were obtained. Functional significance of FTP was affirmed by relative occipital versus parietal EEG slow-wave increase during IAP. Memory and EEG scores were compared between patients with and without FTP (Mann-Whitney U test). A total of 106 patients were included, 73 with posterior cerebral arteries (PCA) without FTP ('non-FTP'), 28 patients with unilateral FTP and 5 with a bilateral FTP. Memory scores were lower when amytal was injected to the hemisphere contralateral to the presumed seizure focus (on the right decreasing from 98.3 to 59.1, and on the left decreasing from 89.1 to 72.4; p < 0.001). When IAP was performed on the side of FTP memory scores were significantly lower (70.8) compared to non-FTP (82.0; p = 0.02). Relative occipital EEG changes were 0.44 for FTP cases and 0.36 for non-FTP patients (p = 0.01). A relationship between vasculature and brain function was demonstrated by lower memory scores and more slow-wave activity on occipital EEG during IAP in patients with foetal-type PCA compared to patients with non-FTP. This suggests an important contribution of brain areas supplied by the PCA to memory function.
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Amobarbital/administración & dosificación , Arteria Carótida Interna/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Trastornos de la Memoria/diagnóstico por imagen , Trastornos de la Memoria/fisiopatología , Memoria/fisiología , Adolescente , Adulto , Arteria Carótida Interna/efectos de los fármacos , Angiografía Cerebral/métodos , Circulación Cerebrovascular/efectos de los fármacos , Niño , Electroencefalografía/métodos , Femenino , Humanos , Infusiones Intraarteriales/métodos , Masculino , Memoria/efectos de los fármacos , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
PURPOSE: In a level 1 university trauma center, an explorative randomized controlled study was performed to compare soft tissue damage and functional outcome after antegrade femoral nailing through a trochanteric fossa (also known as piriform fossa) entry point to a greater trochanter entry point in patients with a femoral shaft fracture. MATERIALS AND METHODS: Nineteen patients were enrolled and randomly assigned to two nail insertion groups; ten patients were treated with an Unreamed Femoral Nail(®) (UFN, Synthes(®), Solothurn, Switzerland) inserted at the trochanteric fossa and nine patients were treated with an Antegrade Femoral Nail(®) (AFN, Synthes(®), Solothurn, Switzerland) inserted at the tip of the greater trochanter. The main outcome measures were pain, gait, nerve and muscle function, along with endurance. Magnetic resonance imaging (MRI), electromyography (EMG), and Cybex isokinetic testings were performed at, respectively, 2 and 6 weeks and at a minimum of 12 months after surgery. RESULTS: The MRI and EMG showed, in both groups, signs of iatrogenic abductor musculature lesions (four in the UFN group and four in the AFN group) and superior gluteal nerve injury (five in the UFN group and four in the AFN group). The isokinetic measurements and the patient-reported outcomes showed moderate reduction in abduction strength and endurance, as well as functional impairment with slight to moderate interference with daily life in both groups, with no appreciable differences between the groups. CONCLUSIONS: Anatomical localization of the entry point seems to be important for per-operative soft tissue damage and subsequent functional impairment. However, the results of this study did not show appreciable differences between femoral nailing through the greater trochanter tip and nailing through the trochanteric fossa.
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OBJECTIVE: To explore whether EEG and MRI abnormalities in the "healthy" hemisphere influence seizure and cognitive outcome after functional hemispherectomy. METHODS: This is a retrospective consecutive cohort study of 43 children who underwent functional hemispherectomy between 1994 and 2008. Results of preoperative EEG recordings were reviewed for the existence of (inter)ictal epileptic or background abnormalities in the contralateral hemisphere. Preoperative MRIs were reexamined for the existence of unequivocal contralateral abnormalities. Postoperative seizure status was assessed, and of 34 children, IQ or mental developmental index (MDI) scores were obtained preoperatively and postoperatively. Seizure freedom was defined as Engel 1A. Contralateral EEG and MRI abnormalities were studied in relation to seizure and cognitive outcome. RESULTS: Thirty-three children achieved seizure freedom (77%). Of the 11 patients with contralateral MRI abnormalities, only 45% were seizure free, compared with 88% of the 32 patients without contralateral MRI lesions (p = 0.030). Children with contralateral MRI abnormalities more often were severely retarded after surgery (MDI/IQ <55; 90% vs 42%, p = 0.030). Postoperative MDI/IQ scores improved in none of the children with, but in 38% of those without contralateral MRI abnormalities (p = 0.034). Contralateral epileptic or background EEG abnormalities did not affect seizure outcome or postoperative cognitive performance. Four of 6 children with bilateral epileptic encephalopathy reached seizure freedom. CONCLUSION: Unambiguous contralateral MRI abnormalities are significantly associated with seizure recurrence, severe mental delay, and lack of cognitive improvement and may be considered a relative contraindication for hemispherectomy. Contralateral EEG abnormalities do not negatively influence postsurgical outcome.
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Trastornos del Conocimiento/patología , Trastornos del Conocimiento/cirugía , Lateralidad Funcional/fisiología , Hemisferectomía/métodos , Convulsiones/patología , Convulsiones/cirugía , Estudios de Cohortes , Electroencefalografía/métodos , Epilepsia/complicaciones , Epilepsia/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Pruebas Neuropsicológicas , Complicaciones Posoperatorias , Estudios Retrospectivos , Convulsiones/etiología , Resultado del TratamientoRESUMEN
OBJECTIVE: Pelvic lymphadenectomy is considered the gold standard to diagnose and possibly treat lymphatic metastases in gynaecological cancer patients. The aim of this study is to evaluate whether all presurgical MRI detected lymph nodes were removed during the systematic pelvic lymph node dissection (PLND) in cervical cancer patients. METHODS: 21 consecutive cervical cancer patients who were scheduled to undergo a PLND were evaluated by a MRI scan prior to surgery and 6 weeks afterwards. All patients had tumour metastasis negative lymph nodes at histopathological examination. RESULTS: On average, 10 pelvic lymph nodes (range 5-17) per patient were detected by presurgical MRI. Postsurgical MRI scans showed that on average 1 (range 0-3) pelvic node per patient was not removed by surgery. In total, 14% of the presurgical MR detected nodes were not removed by surgery (31/225). Approximately half of all lymph nodes that remained after surgery were located in the obturator region. In spite of the remaining nodes, surgery and histopathological examination did detect more nodes than MRI: on average 21 lymph nodes per patient (range 9-59) were removed. Another 2 lymph nodes (range 0-6 per patient) were judged to be newly developed after surgery. CONCLUSION: Although surgery was able to remove many more lymph nodes than those detected by presurgical MRI, 14% of presurgical MRI detected lymph nodes were not removed by PLND. The value of MRI prior to surgery for the detection of pathological lymph nodes is a subject of further research.
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Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía , Adulto , Anciano , Femenino , Humanos , Escisión del Ganglio Linfático , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Pelvis/patologíaRESUMEN
BACKGROUND AND PURPOSE: Patients with intracranial aneurysms are at risk for future development of new aneurysms and growth of additional untreated aneurysms. Because in previous long-term studies duration of follow-up varied widely, the time interval after which screening could be effective remains largely unknown. The purpose of this study was to assess the incidence of de novo aneurysm formation and the growth of additional untreated aneurysms in patients with coiled aneurysms followed up with MR angiography (MRA) after a fixed period of 5 years. MATERIALS AND METHODS: In 65 patients with coiled intracranial aneurysms, high-resolution 3T MRA was performed 5.1 +/- 0.2 years after coiling. MRA follow-up imaging was compared with MRA or CT angiography at the time of coiling. Additional aneurysms detected at MRA follow-up were classified as unchanged, grown, de novo, or incomparable with previous imaging. RESULTS: In 13 of 65 patients (20%), 24 additional aneurysms were found. Four aneurysms were incomparable with previous imaging and 2 of these were clipped. Of the remaining 20 additional aneurysms, 1 was de novo, 1 had grown slightly, and 18 were unchanged. The incidence of de novo aneurysm formation after 5 years was 1.54% (95% confidence interval, 0.01-9.0%). For additional aneurysms known at the time of initial coiling and for the 1 de novo aneurysm, no treatment was indicated. CONCLUSIONS: MRA screening 5 years after coiling for detection of de novo aneurysms and growth of additional untreated aneurysms has a low yield in terms of finding aneurysms that need to be treated.
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Embolización Terapéutica/métodos , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/terapia , Angiografía por Resonancia Magnética , Adulto , Anciano , Bases de Datos Factuales , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Aneurisma Intracraneal/epidemiología , Masculino , Persona de Mediana Edad , Recurrencia , Resultado del TratamientoRESUMEN
In three patients with persistent blood loss from bleeding or abnormal renal vessels, kidney function was preserved by treatment with selective embolisation. The first patient, a 42-year-old woman, suffered from persistent haematuria after undergoing percutaneous nephrolithotripsy on the left side. Because conservative methods had failed and renal artery bleeding as a result of the lithotripsy was suspected, angiography with selective coil embolisation of a segmental branch of the lower pole artery of the kidney was performed. The second patient, a 40-year-old man with severe haemophilia A had been suffering from recurring macroscopic haematuria for a few months. CT showed an arteriovenous malformation in the right kidney. Angiography in combination with embolisation with two detachable balloons resulted in occlusion of the malformation. The third patient, a 23-year-old woman with tuberous sclerosis, presented with left abdominal pain, haematuria and decreasing haemoglobin concentrations. CT revealed a left renal angiomyolipoma, 10 cm in size, with a large internal haematoma. Three pathological branches of the upper pole renal artery were successfully occluded with Gianturco coils. At follow-up after 2, 2.5 and 2.5 years respectively, no recurrence of bleeding had occurred. Selective embolisation should be attempted as means of treatment for persistent renal bleeding if conservative treatment fails. Selective embolisation is minimally invasive and has the important advantage of preserving renal function.
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Embolización Terapéutica , Hematuria/terapia , Adulto , Angiomiolipoma/complicaciones , Malformaciones Arteriovenosas/complicaciones , Malformaciones Arteriovenosas/terapia , Oclusión con Balón , Embolización Terapéutica/métodos , Femenino , Estudios de Seguimiento , Hematoma/complicaciones , Hematuria/etiología , Humanos , Riñón/irrigación sanguínea , Riñón/fisiología , Neoplasias Renales/complicaciones , Litotricia/efectos adversos , Masculino , Arteria Renal/lesiones , Prevención SecundariaRESUMEN
RATIONALE AND OBJECTIVES: To compare the visibility and localization of extratemporal cortical lesions in extratemporal epilepsy by using curved reconstruction (CR) and three-dimensional surface rendering (3D SR) of 3D-acquired MR images and to study the degree of confidence with which localizations are made, particularly at the gyral level. METHODS: Twenty patients with extratemporal epilepsy, based on seizure symptomatology and/or scalp electroencephalographic registrations, with an extratemporal structural lesion on conventional MR imaging, were selected for this study by a neuroradiologist with extensive experience in the assessment of epilepsy patients. Transverse T2 spin-echo, coronal fluid-attenuated inversion recovery, and transverse 3D-acquired/two-dimensionally reconstructed T1 MR images were used for the selection. A second neuroradiologist (observer 1) and a radiology resident (observer 2) assessed CR and 3D SR in random order. Both observers were masked to all patient data. The subjective visibility of lesions and gyral location were scored. The interobserver agreements for lesion visibility and localization and for degree of confidence were compared for CR and 3D SR. RESULTS: For both observers, the lesion was visible in 55% of 3D SRs and 95% of CRs. The proportion with "very clearly visible" lesions on 3D SR was 19% (4/20) according to observer 1 and 30% (6/20) according to observer 2. For CR, this proportion was substantially higher: 55% for both observers. This difference was significant for observer 1 but not for observer 2. The interobserver agreement was high for both methods. Agreement on gyral localization was 28% for CR and 40% for 3D SR. The percentage of similar confidence scores for the same gyral localization and for gyral localization with a maximum difference of one gyrus between the observers did not differ significantly for CR or 3D SR. The observers were more often confident in agreed cases in CR and moderately confident in 3D SR. CONCLUSIONS: These results suggest that CRs of the brain surface are superior to 3D SR for the visualization of extratemporal cortical lesions in patients with drug-resistant extratemporal epilepsy. If lesions are seen, no significant difference was found between the two techniques for localization; however, the degree of confidence appears higher for CR at the gyral level.
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Corteza Cerebral/patología , Epilepsia/patología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Variaciones Dependientes del ObservadorRESUMEN
The performance of an automatic technique for the reduction of patient motion artifacts in digital subtraction angiography was evaluated. Four observers assessed the quality of 104 cerebral digital subtraction angiographic images that were processed by means of both the automatic technique and manual pixel shifting. The automatic technique resulted in better image quality and was considerably less time-consuming.
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Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Intensificación de Imagen Radiográfica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Artefactos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y EspecificidadRESUMEN
The purpose of this study was to assess temporal lobe white matter changes accompanying hippocampal sclerosis on magnetic resonance (MR) imaging using single-voxel 1H MR spectroscopy and to strengthen the hypothesis that these white matter changes are caused by myelin alterations. In 11 patients with histologically proven hippocampal sclerosis, preoperative coronal fluid-attenuated inversion recovery images were visually assessed by two experienced neuroradiologists for hippocampal signal increase and size decrease, atrophy of collateral white matter, and temporal lobe gray/white matter demarcation loss. Single-voxel 1H MR spectroscopy of the white matter of each anterior temporal lobe was also performed, excluding the amygdala and hippocampus. The N-acetyl-aspartate (NAA)/choline and NAA/creatine ratios were calculated. In 12 healthy volunteers both temporal lobes were spectroscopically examined. In all patients the excised hippocampi were histologically assessed for the presence of sclerosis, and the excised neocortical temporal lobes were examined for gray and white matter abnormalities. MRI abnormalities were found on the right in six patients, on the left in four, and one scan was normal. Hippocampal signal increase was seen in nine patients, hippocampal size decrease in ten, atrophy of collateral white matter in nine, and gray/white matter demarcation loss in six. A significant decrease in the NAA/choline ratio was found in temporal lobe white matter ipsilateral to the pathologic hippocampus (symptomatic side), compared with the contralateral, asymptomatic side (P < 0.01), and also compared with controls (P < 0.001). The ipsilateral NAA/creatine ratio was also significantly decreased (P < 0.05) compared with the contralateral side and the control subjects (P < 0.001). Histological examination showed hippocampal sclerosis to a different degree in all patients. Neither gliosis nor cortical dysplasia was found in the ipsilateral, symptomatic temporal lobe. Significant decrease in the mean of NAA/choline ratios is found in temporal lobe white matter of patients with histologically confirmed hippocampal sclerosis. As this indicates neuronal loss or dysfunction, the number of axons may be reduced, with associated decrease in myelin density.
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Epilepsia del Lóbulo Temporal/patología , Hipocampo/patología , Imagen por Resonancia Magnética/métodos , Lóbulo Temporal/patología , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Colina/análisis , Creatina/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis/patologíaRESUMEN
PURPOSE: To determine the accuracy and optimal threshold values of duplex ultrasonography (US) in assessing restenosis of renal artery stents. METHODS: Twenty-four consecutive patients with 33 renal arteries that had previously been treated with placement of a Palmaz stent underwent duplex US prior to intraarterial digital subtraction angiography (DSA), which was the reference standard. Diagnostic accuracy of in-stent peak systolic velocity (PSV) and reno-aortic ratio (RAR = PSV renal stent/PSV aorta) in detecting > 50% in-stent restenosis were evaluated by the receiver operating characteristic curve. Sensitivity and specificity were determined using the optimal threshold values, and using published threshold values: RAR > 3.5 and in-stent PSV > 180 cm/sec. RESULTS: Six examinations were technically inadequate. Nine stents had residual or restenosis > 50% at DSA. The two duplex parameters were equally accurate since areas under the curves were similar (0.943). With optimal threshold values of 226 cm/sec for PSV and 2.7 for RAR, sensitivities and specificities were 100% and 90%, and 100% and 84%, respectively. Using the published duplex criteria resulted in sensitivities and specificities of 100% and 74% for PSV, and 50% and 89% for RAR. CONCLUSION: Duplex US is a sensitive modality for detecting in-stent restenosis if laboratory-specific threshold values are used.
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Obstrucción de la Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/terapia , Stents , Ultrasonografía Doppler Dúplex , Anciano , Angiografía de Substracción Digital , Femenino , Humanos , Masculino , Estudios Prospectivos , Curva ROC , Recurrencia , Arteria Renal/diagnóstico por imagen , Sensibilidad y EspecificidadRESUMEN
RATIONALE AND OBJECTIVES: To evaluate the diagnostic relevance of ipsilateral atrophy of the collateral white matter in the parahippocampal gyrus (ACWMp) and temporal lobe gray/white matter demarcation loss (GWDL) on magnetic resonance imaging in patients with histologically confirmed hippocampal sclerosis. In the second part of this investigation, histologic specimens were analyzed to find an explanation for GWDL. METHODS: Retrospective visual assessment of hippocampal signal intensity and size and of ACWMp and GWDL was performed using 4- to 5-mm coronal T2-weighted spin-echo magnetic resonance images of 80 patients with histologically proven hippocampal sclerosis and of 30 age-matched controls without epilepsy. Frequency of occurrence and likelihood ratios of ACWMp and GWDL were calculated and their contribution to the diagnosis of hippocampal sclerosis was assessed, particularly in patients with no or restricted hippocampal abnormalities (either high signal or smaller size) on magnetic resonance imaging. The second part of the study involved the morphologic histologic assessment of neocortical temporal lobe specimens of all patients. Myelin density was evaluated in specimens of a subgroup of six patients with hippocampal sclerosis and GWDL on MRI and six patients with hippocampal sclerosis without GWDL. RESULTS: ACWMp was found in 68% and GWDL in 65% of patients with hippocampal sclerosis on magnetic resonance imaging. Both features had an infinite positive likelihood ratio. Sixty-two patients (77.5%) had concomitant hippocampal signal increase and smaller size. Eighteen patients (22.5%) had no or restricted hippocampal abnormalities on magnetic resonance imaging. When using ACWMp and GWDL as additional diagnostic parameters, 13 of these 18 patients were more unambiguously diagnosed as having hippocampal sclerosis. No significant morphologic differences were found between GWDL-positive and GWDL-negative specimens. A significantly lower average myelin stain was found in the white matter of the GWDL-positive group compared to the GWDL-negative group. CONCLUSIONS: ACWMp and GWDL can improve the visual diagnosis of hippocampal sclerosis, particularly in patients with no or restricted hippocampal abnormalities. These results suggest that loss of myelin may be the underlying cause of GWDL in association with hippocampal sclerosis.
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Hipocampo/patología , Imagen por Resonancia Magnética , Lóbulo Temporal/patología , Adolescente , Adulto , Atrofia/diagnóstico , Atrofia/patología , Distribución de Chi-Cuadrado , Niño , Epilepsia del Lóbulo Temporal/diagnóstico , Epilepsia del Lóbulo Temporal/patología , Femenino , Humanos , Funciones de Verosimilitud , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esclerosis/diagnóstico , Esclerosis/patología , Sensibilidad y Especificidad , Estadísticas no ParamétricasRESUMEN
PURPOSE: To determine the accuracy of gadolinium-enhanced breath-hold magnetic resonance (MR) angiography in the diagnosis of renal artery stenosis and visualization of accessory renal arteries. MATERIALS AND METHODS: Forty-four patients suspected of having renal artery stenosis and 10 potential kidney donors, all of whom were scheduled to undergo elective intraarterial digital subtraction angiography (DSA), were studied. Three-dimensional gradient-echo gadolinium-enhanced MR angiography was performed at 1.5 T with the following parameters: repetition time, 13.5 msec; echo time, 3.5 msec; flip angle, 60 degrees; 195 x 512 matrix; 400-mm field of view; and 6-cm imaging volume consisting of 15 4-mm-thick partitions reconstructed every 2 mm. Gadopentetate dimeglumine (30 mL) was injected with a power injector. MR angiograms were assessed before the standard of reference, intraarterial DSA, was performed. RESULTS: Four MR angiograms were not evaluable because of poor image quality. MR angiography enabled visualization of all but one of the 121 arteries. In four small accessory arteries, a stenosis could not be excluded owing to inadequate spatial resolution. MR angiography enabled the correct diagnosis in 30 of the 31 arteries with a grade 2 (50%-99%) stenosis and in seven of the 10 occluded arteries. Sensitivity and specificity for correct identification of a grade 2 stenosis were 97% and 92%, respectively. CONCLUSION: Gadolinium-enhanced MR angiography is an accurate, minimally invasive method for detecting renal artery stenosis and is reliable for visualizing accessory renal arteries.
Asunto(s)
Circulación Colateral , Medios de Contraste , Gadolinio DTPA , Angiografía por Resonancia Magnética , Obstrucción de la Arteria Renal/diagnóstico , Arteria Renal/patología , Adulto , Anciano , Angiografía de Substracción Digital , Medios de Contraste/administración & dosificación , Creatinina/sangre , Femenino , Gadolinio DTPA/administración & dosificación , Humanos , Hipertensión/complicaciones , Aumento de la Imagen , Procesamiento de Imagen Asistido por Computador , Inyecciones Intraarteriales , Inyecciones Intravenosas , Trasplante de Riñón , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Arteria Renal/diagnóstico por imagen , Obstrucción de la Arteria Renal/diagnóstico por imagen , Reproducibilidad de los Resultados , Respiración , Sensibilidad y Especificidad , Donantes de TejidosRESUMEN
RATIONALE AND OBJECTIVES: Definition of optimal magnetic resonance (MR) scanning plane and conventional MR sequence for the detection of mesial temporal sclerosis (MTS). METHODS: Coronal and axial T2-weighted images and axial T2-weighted images parallel to the long axis of the hippocampus (APLAH) and coronal inversion recovery (IR) images were obtained in patients with medically intractable temporal lobe epilepsy in their phase 1 preoperative evaluation. Thirty-three consecutive MR scans were reviewed by a panel of three radiologists. Twenty-three patients had MR abnormalities consistent with MTS, and ten scans were normal. To assess the best single scanning technique, another group of three radiologists, who were masked to all patient data, individually assessed the different planes and sequences of the 33 studies presented separately in a random fashion. For each plane and sequence, the likelihood (L) ratio for the correct diagnosis was determined separately. RESULTS: For all planes considered separately, a likelihood ratio of 4.4 was optimal for the coronal T2-weighted images. The likelihood ratio of APLAH T2 was 2.2; of axial T2, 3.9; of coronal IR, indefinite because of 100% specificity. CONCLUSIONS: For the assessment of MTS, coronal T2-weighted images were considered the best single scanning technique.