RESUMO
Objective: To evaluate the value of ultrasound-guided intra-articular anesthetic injection in predicting postoperative outcomes for borderline developmental hip dysplasia (BDDH). Methods: A follow-up study. The clinical data of 37 BDDH patients who received ultrasound-guided intra-articular anesthetic injection and arthroscopic examination in the Department of Sports Medicine, Senior Department of Orthopedics, the Fourth Medical Center of PLA General Hospital from May 2018 to February 2021 were retrospectively analyzed. Among them, there were 17 males and 20 females with a mean age of (37.9±12.8) years. All patients underwent ultrasound-guided intra-articular anesthetic injection prior to arthroscopy, and were evaluated with hip physical examination before and after injection, as well as before and after arthroscopy, in order to obtain the visual analog score (VAS) of pain for seven assessments. The total VAS score was calculated based on these evaluations. Follow-up was conducted for at least 12 months. The effective rate of injection referred to the ratio of the improvement of VAS score after anesthetic injection to the total VAS score before injection. Pearson correlation analysis and Bland-Altman analysis were used to test the correlation between modified Harris hip score (mHHS) after ultrasound-guided intra-articular anesthetic injection and mHHS score after arthroscopic surgery. A binary logistic regression model was established to analyze the substantial clinical benefit (SCB) for patients. Following the logistic regression analysis, a receiver operating characteristic (ROC) curve was constructed to evaluate the predictive power of ultrasound-guided intra-articular anesthetic injection in achieving SCB in those patients. The optimal cut-off value for injection efficacy was determined based on the ROC curve when SCB was achieved. Results: The follow-up time for all patients was (26.3±7.6) months. After anesthetic injection for 20 minutes, the total VAS score of pain [M(Q1,Q3)] decreased from 13(8,23) points before injection to 1(0,4) points; and the mHHS score [M(Q1,Q3)] increased from 60(46,70) points before arthroscopy to 90(84,96) points after, with statistically significant differences before and after injection and before and after arthroscopy (both P<0.001). Pearson correlation analysis showed that the mHHS score after intra-articular anesthetic injection was positively correlated with the mHHS score after surgery (r=0.961, P<0.001). The area under the ROC curve for predicting SCB after arthroscopy with ultrasound-guided intra-articular anesthetic injection was 0.769 (95%CI: 0.561-0.976), the Youden index was 0.663, the cut-off value was 0.569 2, the sensitivity was 96.3%, and the specificity was 70.0%. Conclusions: The results of ultrasound-guided intra-articular anesthetic injection before arthroscopy can indicate the presence of intra-articular lesions, and the degree of pain relief after injection is proportional to the functional recovery after arthroscopy. Patients with intra-articular anesthetic injection efficacy>56.92% have better results in hip arthroscopy.
Assuntos
Anestesia , Displasia do Desenvolvimento do Quadril , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Articulação do Quadril/cirurgia , Seguimentos , Artroscopia/métodos , Resultado do Tratamento , Estudos Retrospectivos , Dor , Ultrassonografia de IntervençãoRESUMO
Objective: To evaluate the effect of fluoroscopy-free technique in the arthroscopic treatment of femoroacetabular impingement syndrome (FAIS). Methods: A retrospective cohort study. Clinical data of FAI patients treated with hip arthroscopy in the No.4 Medical Center, PLA General Hospital from October 2018 to December 2021 were retrospectively analyzed. The patients were divided into two groups according to the surgical procedure: the fluoroscopy group and the fluoroscopy-free group. The operation time and modified Harris hip score (mHHS), international hip outcome tool (iHOT12) and visual analogue scale (VAS) of hip joint pain before and after the operation were observed and compared between the two groups. And the incidence of surgical complications in the two groups were compared too. Results: A total of 460 patients (213 males and 247 females) [aged (32.6±8.3) years (15-67 years)] with valid follow-up were included in this study. There were 275 cases in the fluoroscopy-free group and 185 cases in the fluoroscopy group. The operation time was shorter in the fluoroscopy-free group when compared with that in the fluoroscopy group, and the difference was statistically significant [(93.36±12.54) min vs (115.62±6.03) min, P<0.001]. In both groups, the VAS scores decreased and the mHHS scores and iHOT12 scores improved significantly at the last follow-up when compared with those before the operation (all P<0.001); however, there was no significant difference in the scores between the two groups (all P>0.05). The complication rate in the fluoroscopy-free group was 10.18% (28/275), and it was 10.81%(20/185) in the fluoroscopy group (P=0.829). Conclusion: Fluoroscopy-free hip arthroscopy technique for FAI can avoid radiation and shorten the operation time, but it does not increase the incidence of complications with reliable clinical outcomes.
Assuntos
Impacto Femoroacetabular , Masculino , Feminino , Humanos , Impacto Femoroacetabular/cirurgia , Articulação do Quadril/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Artroscopia/métodos , Atividades Cotidianas , SeguimentosRESUMO
Objective: To investigate the clinical efficacy of bilateral gluteal muscle contracture treated with inside-out iliotibial band release under arthroscopy in the supine position. Methods: A prospective non-randomized controlled trial. Forty-six patients admitted to the Department of Sports Medicine, Senior Department of Orthopedics, the Fourth Medical Center of PLA General Hospital from April 2021 to August 2022 for bilateral gluteal muscle contracture and proposed surgical treatment were enrolled. The subjects were divided into two groups according to the preferred surgical protocols of the patients: the supine position group was treated with inside-out iliotibial band release under arthroscopy in the supine position, and the operation in lateral position group was carried out with outside-in iliotibial band release under arthroscopy in the lateral position. The total duration of non-surgical operations and the total duration of surgical operations were recorded for all patients. The gluteal muscle contracture disability scale within 3 days before surgery and at least 2 months after surgery were compared between the two groups, and the occurrence of complications between the two groups was compared too. Results: There were 26 cases in the supine position group, 11 males and 15 females with a mean age of (31.8±7.3) years; and there were 20 cases in the lateral position group, 7 males and 13 females with a mean age of (30.6±6.3) years. The differences in gender, age, body mass index (BMI) and postoperative follow-up time between the two groups were not statistically significant (all P>0.05). The total duration of non-surgical operations was shorter in the supine position group than in the lateral position group [(47.9±10.4) min vs (63.9±7.5) min, P<0.001]. There was no statistically significant difference in the total duration of surgical operations between the supine position group and the lateral position group [31.0(27.0, 43.5) min vs 33.0(24.8, 38.0) min, P>0.05]. The postoperative gluteal muscle contracture disability scales were significantly improved in both the supine position and lateral position groups when compared with those before the operation [93.0 (85.0, 98.0) vs 61.0 (50.5, 66.8), P<0.001 and 88.5±6.9 vs 63.6±9.6, P<0.001, respectively]. There was no statistically significant difference in the gluteal muscle contracture disability scale between the supine position and lateral position groups before and 2 months after surgery [59.3±11.9 vs 63.6±9.6 and 93.0 (85.0, 98.0) vs 89.5(84.0, 94.8), both P>0.05, respectively]. Two patients in each group developed subcutaneous hematoma after surgery, and all of them resolved within 2 weeks after surgery, the difference in complication incidence rate was not statistically significant (P>0.05). No postoperative complications such as fat liquefaction in the operated area, infection, decreased hip abductor muscle strength or nerve injury in the lower extremity were observed in both groups. Conclusion: The treatment of bilateral gluteal muscle contracture by inside-out iliotibial band release under arthroscopy in the supine position can effectively improve clinical efficiency, with definite efficacy, and it is an operative program worth promoting.
Assuntos
Artroscopia , Contratura , Masculino , Feminino , Humanos , Adulto Jovem , Adulto , Artroscopia/métodos , Estudos Prospectivos , Decúbito Dorsal , Contratura/cirurgia , Músculo Esquelético/cirurgia , Resultado do Tratamento , Nádegas/cirurgiaRESUMO
A 32-year-old, gravida 2 para 0+1, was managed in Selayang Hospital, Selangor for uterine fibroids in pregnancy and placenta previa major. The lady went into preterm labour at 33 weeks, requiring emergency Caesarean section. Intraoperatively, we found a thinned-out bulge between the intramural uterine fibroids at the posterior uterine wall, which then perforated and was repaired. Persistent bleeding post operatively led to relaparotomy and hysterectomy. Histology of the uterus reported arteriovenous malformation (AVM). We postulate the possibility of these lesions coexisting with uterine fibroids. Screening for uterine AVMs in patients with fibroids may lead to early detection with option of embolization; deferring the need for hysterectomy.
Assuntos
Malformações Arteriovenosas , Leiomioma , Adulto , Malformações Arteriovenosas/complicações , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/cirurgia , Cesárea , Feminino , Humanos , Histerectomia , Recém-Nascido , Leiomioma/complicações , Leiomioma/epidemiologia , Leiomioma/cirurgia , Gravidez , Útero/cirurgiaRESUMO
OBJECTIVES: The contrast enhancement of acutely infarcted myocardium produced by the nonionic magnetic susceptibility-enhancing agent dysprosium diethylenetriamine pentaacetic acid-bis-methylamide (DyDTPA-BMA [S-043 Injection]) was assessed in the current study to establish the lowest dose that would yield optimal contrast between normal and acutely infarcted myocardium. BACKGROUND: Magnetic susceptibility contrast agents enhance differences between normal and ischemic tissue by reducing the signal of the normally perfused tissue to which they distribute. METHODS: Acute myocardial infarctions were produced by ligation of the left coronary artery. At 3 to 4 h after occlusion, a dose of 0.1, 0.3 or 0.5 mmol/kg of DyDTPA-BMA was injected intravenously into eight rats each in group 1, 2 or 3, respectively; a fourth group of seven rats served as a control group. Nuclear magnetic resonance (NMR) transverse relaxation time (T2)-weighted images (electrocardiographically gated to every 5th beat, echo delay time [TE] = 60 ms) were acquired before and for 1 h after administration of contrast agent. RESULTS: Images obtained before the injection of contrast agent showed moderate differences in signal intensity between normal and infarcted myocardium (p < 0.05). The contrast enhancement and the duration of delineation between infarcted and normal myocardium produced by this agent were dose dependent. At doses of 0.1, 0.3 and 0.5 mmol/kg, DyDTPA-BMA produced signal loss in normal myocardium: 63 +/- 5%, 41 +/- 4% and 28 +/- 4% of the baseline values, respectively, without any significant reduction in signal intensity of the infarcted region. The reduction in signal of normal myocardium and delineation of the infarct persisted for 5 min at a dose of 0.1 mmol/kg, for 20 min at a dose of 0.3 mmol/kg and for 40 min at a dose of 0.5 mmol/kg. No change in signal intensity or signal intensity ratio between normal and infarcted myocardium was observed in the control group during the same observation period. CONCLUSIONS: These results suggest that low doses of this agent, comparable to those of longitudinal relaxation time (T1)-enhancing agents, can delineate acutely infarcted myocardium. A dose of 0.3 mmol/kg of DyDTPA-BMA (S-043 Injection) provides reasonably persistent demarcation of acute myocardial infarction. Because this dose dramatically suppresses the NMR signal of normal myocardium, it shows the infarcted region as a region of high intensity (bright spot) on NMR images.
Assuntos
Espectroscopia de Ressonância Magnética/métodos , Infarto do Miocárdio/diagnóstico , Compostos Organometálicos , Ácido Pentético , Animais , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Estudos de Avaliação como Assunto , Feminino , Injeções Intravenosas , Músculos/metabolismo , Infarto do Miocárdio/patologia , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/farmacologia , Ácido Pentético/administração & dosagem , Ácido Pentético/farmacologia , Ratos , Ratos Sprague-Dawley , Processamento de Sinais Assistido por Computador , Fatores de TempoRESUMO
Small molecular weight nuclear RNAs (SnRNA) purified from the chromatin of SV40-transformed W138 human fibroblasts have been found to stimulate transcription of chromatin in homologous isolated nuclei as well as in nuclei of untransformed human and monkey cells. Stimulation in normal cell nuclei involves an increase in both initiation sites and rate of elongation of RNA chains. Fractionation of the SnRNA in polyacrylamide gradient slab gels revealed that the "active" RNA was 160-175 nucleotides in length.
Assuntos
Cromatina/genética , RNA/farmacologia , Transcrição Gênica/efeitos dos fármacos , Linhagem Celular , Núcleo Celular/metabolismo , Transformação Celular Viral , Eletroforese em Gel de Poliacrilamida , Humanos , Peso Molecular , RNA/metabolismo , Vírus 40 dos Símios , PeleRESUMO
RATIONALE AND OBJECTIVES: Magnetic resonance imaging (MRI) was used to demonstrate the infarction size in reperfused ischemic myocardium of normal and hypertrophied hearts, and to test the hypothesis that hypertrophied hearts manifest greater susceptibility to ischemia. METHODS: Normal rats (n = 11) and rats subjected to left ventricular hypertrophy (LVH) by aortic banding (n = 13) were studied. After 7 weeks, the left coronary artery was occluded for 25 minutes and reperfused for 1 hour before MRI. Electrocardiogram-gated spin-echo images were acquired before and after administration of 0.3 mmol/kg gadoteridol. To quantify the hyperintense area demarcated by gadoteridol, 3 transaxial images were acquired at different levels. Jeopardy and infarcted areas were measured in the same three slices postmortem using blue dye and triphenyltetrazolium chloride (TTC) stain, respectively. RESULTS: Before administration, there was no significant difference in signal intensity between nonischemic (0.42 +/- 0.03 arbitrary units) and ischemic (0.41 +/- 0.03) myocardium in either group. After gadoteridol injection, signal intensity of the reperfused injured region was higher than that of nonischemic myocardium (1.48 +/- 0.16 vs. 0.72 +/- 0.06, P < .05). Magnetic resonance delineation of the hyperintense area persisted for at least 30 minutes. The size of the hyperintense area was larger in LVH than in control hearts (25 +/- 5% vs. 7 +/- 3% of LV surface area, P < .05) and did relate closely to the area of myocardial infarction (r = .97), but not with the jeopardy area (r = .42). On TTC staining, the infarction size also was significantly greater in LVH than in normal group (18 +/- 5% vs. 5 +/- 2% of LV surface area, P < .05). The jeopardy areas of normal and LVH hearts showed no significant difference (46 +/- 2% vs. 47 +/- 3%). CONCLUSION: Magnetic resonance imaging confirms the concept that reperfused myocardial injury is larger in LVH than normal hearts after brief coronary occlusion. Contrast-enhanced MRI can define the size of reperfused myocardial injury. Thus, MRI is a suitable technique to assess conditions accentuating ischemic injury.
Assuntos
Compostos Heterocíclicos , Hipertrofia Ventricular Esquerda/patologia , Imageamento por Ressonância Magnética/métodos , Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/patologia , Compostos Organometálicos , Animais , Meios de Contraste , Gadolínio , Hipertrofia Ventricular Esquerda/complicações , Traumatismo por Reperfusão Miocárdica/complicações , Ratos , Ratos Sprague-DawleyRESUMO
RATIONALE AND OBJECTIVES: The purposes of this study are to evaluate the first-pass profile of gadolinium-BOPTA/Dimeg (Gd-BOPTA/Dimeg) during its transit through hearts subjected to acute myocardial infarction, and to delineate these infarcted regions by the use of ultrafast magnetic resonance imaging (MRI). METHODS: Regional ischemia was induced in anesthetized rats by occluding the left coronary artery. Imaging parameters for single shot EPI included TE, 10 mseconds; AT, 33 mseconds; and 64 x 64-pixel matrix. Consecutive images were obtained every 1 to 2 seconds over a 30-second period. After approximately two images, Gd-BOPTA/Dimeg was injected intravenously (0.05 and 0.25 mmol/kg). RESULTS: Gd-BOPTA/Dimeg (0.05 mmol/kg), with inversion recovery EPI, produced a substantial increase in signal intensity of right and then left ventricular blood. Normally perfused myocardium also was enhanced, but not the acutely infarcted region. Clear delineation of the infarcted region as negatively enhanced "cold spots" persisted for at least 20 seconds. Gd-BOPTA/Dimeg (0.25 mmol/kg) with standard gradient-recalled EPI produced a different profile of signal intensity changes. Signal intensities of ventricular blood and normal myocardium were greatly reduced, leaving the infarcted zone as a positively enhanced "hot spot." Delineation of the infarcted region persisted for 6 to 8 seconds. The infarcted zone detected with MRI corresponded to that observed at autopsy. CONCLUSIONS: Regions of acute myocardial infarction can be detected as negatively enhanced "cold spots" or positively enhanced "hot spots" by studying the first-pass dynamics of Gd-BOPTA/Dimeg through hearts with regional ischemia by use of single shot EPI.
Assuntos
Imagem Ecoplanar , Meglumina/análogos & derivados , Infarto do Miocárdio/diagnóstico , Compostos Organometálicos , Animais , Feminino , Infarto do Miocárdio/patologia , Miocárdio/patologia , Ratos , Ratos Sprague-DawleyRESUMO
RATIONALE AND OBJECTIVES: This study compared the areas demarcated by a T1-enhancing agent, Gd-DTPA-BMA, and a magnetic susceptibility agent, Dy-DTPA-BMA, with 201thallium autoradiography (indicator of perfusion) and postmortem histochemical staining with triphenyltetrazolium chloride (TTC)(indicator of infarction). METHODS: Thirteen rats were subjected to coronary artery occlusion for 3 to 4 hours before acquisition of four sets of electrocardiogram-gated spin-echo magnetic resonance (MR) images: T1-weighted images before and after 0.2 mmol/kg Gd-DTPA-BMA; and T2-weighted images before and after 0.3 mmol/kg Dy-DTPA-BMA. After MR imaging, intravenous 201thallium delineated the area of decreased myocardial perfusion. At autopsy, TTC staining delineated the area of myocardial infarction. RESULTS: A myocardial region in the distribution of the occluded artery was delinated as a hyperintense area ("hot-spot") by Dy-DTPA-BMA and as a hypointense area ("cold-spot") by Gd-DTPA-BMA. The hyperintense area demarcated by Dy-DTPA-BMA (51 +/- 3% of the area of the midequitorial slice of the left ventricle) showed a closer relationship to the area of decreased myocardial perfusion (jeopardized area) (46 +/- 3%), determined by 201thallium autoradiography, than the area of myocardial infarction (36 +/- 4%), determined by histochemical staining. However, the hypointense area demarcated by Gd-DTPA-BMA (29 +/- 2%) did not relate as closely to the area of decreased myocardial perfusion (slope = 0.54) or the area of myocardial infarction (r = 0.46). CONCLUSIONS: The abnormal myocardial area delineated by the magnetic susceptibility agent showed a closer relationship to the area of deficient myocardial perfusion (jeopardy area) after coronary occlusion than that defined by T1-enhancing contrast media.
Assuntos
Meios de Contraste , Gadolínio DTPA , Imageamento por Ressonância Magnética , Infarto do Miocárdio/diagnóstico , Miocárdio/patologia , Animais , Autorradiografia , Feminino , Infarto do Miocárdio/patologia , Variações Dependentes do Observador , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Ratos , Ratos Sprague-Dawley , Coloração e Rotulagem , Sais de Tetrazólio , Radioisótopos de TálioRESUMO
In the detection of prostate cancer, the most important role of imaging is ultrasound-guided prostatic biopsy. In the staging evaluation of prostate cancer, each presently used modality--transrectal US (TRUS), MR imaging, CT, nuclear medicine, and positron emission tomography--has advantages and disadvantages. Evidence-based guidelines on the use of CT and nuclear medicine bone scan, in assessing the risk of distant spread of prostate cancer, are available. There is no consensus and there are no guidelines, however, for the use of imaging in the evaluation of prostate cancer local tumor extent. Results on the value of TRUS vary widely, and prospective multicenter studies suggest that TRUS is no better than digital rectal examination in predicting extracapsular extension. MR imaging offers the most promise for local staging of prostate cancer, but it must resolve problems of reproducible image quality and interobserver variability, and it should prove its efficacy in multicenter trials before it can be recommended for general clinical use. The introduction of MR spectroscopic imaging further expands the value of MR imaging, offering anatomic and metabolic evaluation of prostate cancer.
Assuntos
Diagnóstico por Imagem , Neoplasias da Próstata/diagnóstico , Biópsia , Medicina Baseada em Evidências , Humanos , Aumento da Imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Estudos Multicêntricos como Assunto , Estadiamento de Neoplasias , Variações Dependentes do Observador , Exame Físico , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Neoplasias da Próstata/diagnóstico por imagem , Medição de Risco , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X , Ultrassonografia de IntervençãoRESUMO
One of the single most important considerations in clinical management of the patient with prostate cancer is whether or not metastatic disease is present. The identification of metastatic disease in a patient with newly diagnosed prostate cancer represents an absolute contraindication to definitive local therapies such as radial prostatectomy or radiation therapy. Similarly, the identification of metastatic disease in a patient with disease recurrence after definitive local therapy represents an absolute contraindication to salvage radiotherapy or cryosurgery. Patients with metastatic disease do not benefit from definitive therapy, and the cost and morbidity associated with such treatment should therefore be avoided in these patients. Because of the significance of metastatic disease to clinical management, it is important for the diagnostic radiologist to be aware of important considerations in the metastatic work-up of patients with newly diagnosed prostate cancer and patients with suspected cancer recurrence after definitive local therapy.
Assuntos
Metástase Linfática/diagnóstico , Neoplasias da Próstata/patologia , Neoplasias Ósseas/secundário , Contraindicações , Criocirurgia , Custos de Cuidados de Saúde , Humanos , Masculino , Recidiva Local de Neoplasia/diagnóstico , Prostatectomia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Radioterapia , Terapia de SalvaçãoRESUMO
The applications of combined MR imaging and MR spectroscopic imaging of prostate cancer have expanded significantly over the past 10 years and have reached the point of clinical trial results to test robustness and clinical significance. MR spectroscopic imaging extends the diagnostic evaluation of prostate cancer beyond the morphologic information provided by MR imaging throughout the detection of cellular metabolites. The combined metabolic and anatomic information provided by MR imaging and MR spectroscopic imaging has allowed a more accurate assessment of the presence, location, extent, and aggressiveness of prostate cancer both before and after treatment. This information has already demonstrated the ability to improve therapeutic planning for individual prostate cancer patients and shows great promise in the assessment of therapeutic response and the evaluation of new treatment regimes.
Assuntos
Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Neoplasias da Próstata/diagnóstico , Protocolos Clínicos , Ensaios Clínicos como Assunto , Humanos , Masculino , Estadiamento de Neoplasias , Planejamento de Assistência ao Paciente , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Resultado do TratamentoRESUMO
The results of our study highlight the need for change in the pretreatment workup of clinical stage Ib cervical cancer. The routine use of excretory urography, barium enema, cystoscopy,and sigmoidoscopy is not justified. MR evaluation is recommended in patients with lesions larger than 2 cm (the group with the greatest increase in predictive value). Although CT scanning is not recommended for the evaluation of parametrial invasion, both CT scanning and MR imaging provide similar positive and negative posttest probabilities for the evaluation of nodal disease.
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Diagnóstico por Imagem/economia , Neoplasias do Colo do Útero/diagnóstico , Teorema de Bayes , Análise Custo-Benefício , Feminino , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética/economia , Estadiamento de Neoplasias/economia , Probabilidade , Sensibilidade e Especificidade , Resultado do Tratamento , Neoplasias do Colo do Útero/economia , Neoplasias do Colo do Útero/patologiaAssuntos
DNA/biossíntese , Polyomavirus , Animais , Isótopos de Carbono , Células Cultivadas/metabolismo , Centrifugação com Gradiente de Concentração , Replicação do DNA , DNA de Cadeia Simples/biossíntese , DNA Viral/biossíntese , Embrião de Mamíferos , Técnicas In Vitro , Camundongos , Peso Molecular , Timidina/metabolismo , Fatores de Tempo , TrítioAssuntos
Neoplasias Abdominais/economia , Imageamento por Ressonância Magnética/economia , Neoplasias Pélvicas/economia , Especialização/economia , Tomografia Computadorizada por Raios X/economia , Neoplasias Abdominais/diagnóstico , Neoplasias Abdominais/terapia , Análise Custo-Benefício , Humanos , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/economia , Recidiva Local de Neoplasia/terapia , Neoplasias Pélvicas/diagnóstico , Neoplasias Pélvicas/terapia , Estados UnidosAssuntos
Prostatectomia , Neoplasias da Próstata/diagnóstico , Biópsia por Agulha , Intervalo Livre de Doença , Humanos , Imageamento por Ressonância Magnética , Masculino , Recidiva Local de Neoplasia , Avaliação de Resultados em Cuidados de Saúde , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Ultrassonografia , Estados UnidosAssuntos
Anestesia Epidural , Anestesia Obstétrica , Miastenia Gravis , Complicações na Gravidez , Adolescente , Feminino , Humanos , Recém-Nascido , Masculino , GravidezRESUMO
Thin interslice gaps and large imaging volumes are detrimental to MR signal and contrast, especially when the body coil is used. To show the influence of these two factors on fat and water signal and contrast, we performed a series of in vitro experiments. A cylinder filled with water and another filled with oil were imaged transaxially (TR = 2000 msec; TE = 20 and 70 msec) with different interslice gaps (0-150% slice thickness). A series of images was obtained to cover a 40-cm imaging volume. Increasing interslice gap thickness increased water signal without affecting fat signal, resulting in a decrease in fat/water contrast on TE = 20 msec (less T1-weighting) and increasing contrast on TE = 70 msec (more T2-weighting). Contrast nearly doubled when the interslice gap was increased from 10% to 75%. As slices moved away from the central slice, fat and water signals decreased slowly to 12.5 cm off center. Signal loss was significant with offsets greater than 12.5 cm. These results emphasize that to obtain proper contrast on T2-weighted images, the optimal interslice gap should be used and the region of interest should be near the central slice. Otherwise, images should be interpreted with caution.
Assuntos
Imageamento por Ressonância Magnética/métodos , Água Corporal , Humanos , Lipídeos , Imageamento por Ressonância Magnética/instrumentação , Modelos Estruturais , Tecnologia RadiológicaRESUMO
Suicide rates in Hong Kong increased with age, and the highest suicide rate occurred among the oldest age groups. Hong Kong has one of the highest elderly suicide rates in the world. The elderly suicide rate was four to five times above the average. Furthermore, gender differences were observed among different marital status groups. For example, single males had a much higher rate than single females and married males had a higher rate than their widowed counterparts. The suicide rate for an economically inactive person was six times higher than for an active one. Jumping has become increasingly common and seems to substitute for other methods of suicide. Winter months and the Chinese New Year period had the lowest suicide occurrence. Some explanations are given.