Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 22
Filtrar
Añadir filtros








Intervalo de año
1.
Chinese Journal of Radiological Medicine and Protection ; (12): 716-721, 2022.
Artículo en Chino | WPRIM | ID: wpr-956850

RESUMEN

Objective:To investigate the feasibility of reducing radiation dose in coronary CT angiography for patients with arrhythmia with absolute phase and narrow window in prospective electrocardiogram-gating.Methods:200 patients with arrhythmia underwent coronary CT angiography procedure with prospective electrocardiogram-gating adaptive sequence in dual source CT were randomly divided into 2 groups according to the scan mode. Group A was scanned with absolute phase and narrow window(250-450 ms) and group B uesd relative phase and wide window (30%-75%). The other parameters and injection protocol of contrast media were the same in 2 groups. Both image quality and radiation dose of the 2 groups were analyzed.Results:No significant difference of image quality was found between the 2 groups. CTDI vol, DLP, E of group A were all lower than those in group B [CTDI vol : (16.71±8.35) vs.(29.35±17.90)mGy , DLP: (231.04±114.86) vs.(398.27±238.40)mGy·cm , E: (3.23±1.60) vs.(5.57±3.33)mSv, t=-6.40, -6.32、-6.32, P<0.05] . The patients with repeat scan cycles in group A and group B were 81 vs. 22 for 0 cycle , 17 vs. 62 for 1 cycle, 2 vs. 10 for 2 cycles, 0 vs. 6 for 3 cycles( χ2=70.76, P<0.05). Conclusions:The prospective electrocardiogram-gating adaptive CCTA sequence with absolute phase and narrow window can reduce radiation dose while the image quality meets the requirementsfor patients with arrhythmia.

2.
Chinese Journal of Radiological Medicine and Protection ; (12): 796-800, 2018.
Artículo en Chino | WPRIM | ID: wpr-708136

RESUMEN

With the continuous development of CT technology,coronary artery CT angiography (CCTA) has been clinically recognized as a rapid and accurate examination method.At the same time,its radiation effects and the toxic effects of contrast agents have also attracted everyone's attention.At present,many new techniques for reducing radiation dose and iodine dosage of contrast medium are used in clinical practice.This paper aims to review the dual-low scanning techniques and progress of CCTA in recent years.

3.
Chinese Journal of Medical Imaging ; (12): 101-104, 2017.
Artículo en Chino | WPRIM | ID: wpr-505835

RESUMEN

Purpose To investigate the feasibility of 30 ml low-dose contrast medium in reducing the accumulation of contrast medium in venous system while maintaining enough artery enhancement in 256-slice CT angiography (CTA) of intracranial and cervical arteries.Materials and Methods Sixty patients with head and neck CTA were recruited prospectively,and they were randomly divided into group A and group B.The scan parameters of the two groups were identical,but the protocol of contrast medium injection was different.Group A was injected 60 ml contrast medium and 30 ml saline successively with the rate of 4.0 ml/s.Group B was injected 30 ml contrast medium and 50 ml saline successively with the rate of 5.0 ml/s.CT attenuation values of aortic arch,common carotid artery,subclavian artery,cerebral middle artery,superior vena cava,innominate vein,subclavian vein,internal jugular vein were measured,and the image quality was evaluated.Results The average CT values of superior vena cava,right innominate vein,right subclavian vein in two groups had significant differences (P<0.05).The average CT values of left brachial vein,left subclavian vein,left and right internal jugular vein in two groups had no significant differences (P>0.05).The average CT values of aortic arch,left and right common carotid artery,left and right subclavian artery,left and right cerebral middle artery in two groups had significant differences (P<0.05).The scores of image quality in two groups also had significant difference (P<0.05).Conclusion Head-and-neck CTA with 30 ml low-dose contrast medium is feasible and the images are satisfactory for diagnosis,which can reduce the dose of contrast medium and accumulation of contrast medium in venous system,while maintaining enough artery enhancement.

4.
Chinese Journal of Dermatology ; (12): 291-294, 2017.
Artículo en Chino | WPRIM | ID: wpr-511354

RESUMEN

Objective To measure the expression of interleukin-13 (IL-13) and its receptors in mycosis fungoides (MF) lesions,and to investigate their clinical significance.Methods A total of 34 paraffin-embedded specimens of MF,which was confirmed by clinical and histopathological features,immunophenotyping and/or T-cell receptor gene rearrangements,were collected from Hangzhou Third People's Hospital between January 2010 and March 2016.According to the tumor-node-metastasis (TNM) staging system,5 patients were at stage I A,9 at stage Ⅰ B,17 at stage Ⅱ A,and 3 at stage Ⅱ B.Ten normal skin tissue specimens served as controls.Immunohistochemical study was conducted to measure the expression of IL-13,IL-13Rα1 and IL-13Rα2.Results IL-13,IL-13Rα1 and IL-13Rα2 were all expressed in atypical lymphoid cells and epidermotropic lymphoid cells in MF lesions at various stages.IL-13Rα2 was highly expressed in all the MF lesions.None of IL-13 and its receptors were expressed in normal skin tissues and lymphocytes.The expression rates of IL-13 and its receptors in MF lesions increased along with the progression of MF.Additionally,the expression rates of IL-13 (10.00% ± 3.14%),IL-13Rα1 (21.43% ± 6.88%) and IL-13Ro2 (31.14% ± 6.38%) significantly decreased in MF lesions at stage Ⅰ compared with those at stage Ⅱ (27.50% ± 11.00%,39.45% ± 9.43%,44.40% ± 11.15%,respectively,all P < 0.05),but no significant differences were observed between stage Ⅰ A and Ⅰ B,or between stage Ⅱ A and Ⅱ B (P > 0.05).Conclusion IL-13 and its receptors,especially IL-13Rα2,may be expected to serve as biomarkers for early diagnosis of MF and prediction of its biological behaviors.

5.
Chinese Journal of Dermatology ; (12): 637-641, 2014.
Artículo en Chino | WPRIM | ID: wpr-454711

RESUMEN

Objective To investigate the changes of T helper type 17 (Thl7) cells and regulatory T (Treg) cells in different stages of mycosis fungoides.Methods Flow cytometry was performed to determine the percentage of Treg and Th17 cells in peripheral blood from 28 patients with mycosis fungoides (MF),13 patients with large plaque parapsoriasis (PP),17 patients with lichen planus (LP) and 10 healthy human controls,and immunohistochemistry to detect the expressions of forkhead box protein 3 (FOXP3) and interleukin (IL)-17 in tissue specimens from 40 patients with MF,13 with PP,17 with LP and 10 healthy human controls.Statistical analysis was carried out by one-way analysis of variance and Pearson correlation analysis.Results As far as the percentage of Treg cells in peripheral blood was concerned,MF,PP and LP patients were significantly higher than the healthy controls (8.09% ± 1.68%,6.53% ± 1.67% and 2.84 % ± 1.16% vs.1.01% ± 0.35,all P< 0.05),PP patients were higher than LP patients and healthy controls (both P < 0.05),and LP patients were higher than healthy controls (P < 0.05).The percentage of Th17 cells in peripheral blood was significantly increased in MF patients compared with PP patients,LP patients and healthy controls (3.22% ± 0.82% vs.2.46% ± 0.79%,1.38% ± 0.47% and 0.59% ± 0.30%,all P < 0.05).Elevated expression rate of FOXP3 was observed in MF,PP and LP lesions as compared with normal skin (14.94% ± 4.46%,11.95% ± 4.72%,6.32% ± 2.81% vs.3.43% ± 1.79%,all P < 0.05),and in MF and PP lesions compared with LP lesions (both P < 0.05),but no significant difference was observed between MF and PP lesions (P > 0.05).There was a significant increase in the expression rate of IL-17 in MF lesions compared with PP lesions,LP lesions and normal skin (15.89% ± 4.27% vs.12.02% ± 3.34%,4.84% ± 1.93% and 2.62% ± 0.89%,all P < 0.05).The Th17/Treg ratio in peripheral blood was significantly lower in MF and PP patients than in LP patients and healthy controls (0.41 ± 0.11 and 0.39 ± 0.12 vs.0.50 ± 0.06 and 0.57 ± 0.19,all P < 0.05).A positive correlation was observed between the proportion of Thl7 cells and Treg cells (r =0.423,P < 0.05) in patients with early-stage MF,but not in those with tumor-stage MF.The proportion of Th17 cells decreased,but that of Treg cells continuously increased in patients with tumor-stage MF.However,no significant difference was noted in the proportion of Thl7 cells or Treg cells among patients with different stages of MF.Conclusion The imbalance between Treg and Th17 cells may be involved in the occurrence and development of MF.

6.
Chinese Journal of Radiological Medicine and Protection ; (12): 783-786, 2014.
Artículo en Chino | WPRIM | ID: wpr-466233

RESUMEN

Objective To establish a function model to modulate the tube current according to the chest circumference at Coronary CTA scan,and to evaluate the feasibility of using the function model individually.Methods Sixty-eight consecutive patients who underwent thoracic scan with automatic current modulation were studied to establish a function model of tube current and chest circumference.The other 64 consecutive patients underwent coronary CTA scan using the new function model.The image quality was scored,and the noise,tube current and radiation dose were recorded and statistically evaluated.Results The POW function model was the best one to adjust tuber current to the chest circumference (R2 =0.691,P < 0.05).The mean image quality score,noise,tube current,radiation dose (CTDIvol) and dose-length product (DLP) were (3.38±0.72) scores,(31.02 ±3.97) HU,(390.63± 89.30) mA,(34.83±10.72) mGy,(751.67 ±175.16) mGy·cm,respectively.Conclusions Tube current modulation based on the chest circumference would be feasible to reduce the radiation dose individually in coronary CT angiography.

7.
Chinese Journal of Dermatology ; (12): 83-86, 2012.
Artículo en Chino | WPRIM | ID: wpr-424543

RESUMEN

ObjectiveTo study the roles of aquaporin 3(AQP3),Caspase 14 and bleomycin hydrolase(BH) in skin barrier in patients with chronic eczema and to tackle the mechanisms underlying the therapeutic effect of narrow-band ultraviolet B(NB-UVB) on eczema.MethodsTransepidermal water loss (TEWL)and water content of skin were detected by a muhi-functional skin tester in lesions and non-lesional skin of 30 patients with chronic eczema.The protein expressions of AQP3,Caspase 14 and BH were detected by immunohistochemistry in tissue specimens from lesioual and non-lesional skin of these patients.Cultured keratinocytes were irradiated with 3 different doses(400,800,1200 mJ/cm2) of UVB,and Western blot was performed to quantify the protein expressions of AQP3,Caspase 14 and BH at 24 hours after the irradiation.ResultsThere was a significant decrease in water content of skin(11.32 ± 5.25 vs.49.68 ± 8.62) but an increase in TEWL (86.28 ± 16.35 vs.14.62 ± 6.68) in lesional skin compared with non-lesional skin from the patients with chronic eczema(both P < 0.05).The protein expression levels of AQP3,Caspase 14 and BH in lesional skin were 5.3 times,4.2 times and one-third of,those in non-lesional skin from the patients,respectively,and significant differences existed between the lesional and non-lesional skin in the 3 parameters (all P < 0.05 ).After irradiation with NB-UVB at 400,800 and 1200 mJ/cm2,the expression level of AQP3 in keratinocytes was decreased by 52%,77% and 84%,respectively,and that of Caspase 14 was decreased by 18%,22% and 78%,respectively,compared with unirradiated keratinocytes (all P < 0.05).A marked decrease(by 66%) was also observed in the expression of Caspase 14 in keratinocytes after irradiation with NB-UVB at 1200 mJ/cm2(P < 0.05).ConclusionsThe impairment of skin barrier function in chronic eczema may be related to the downregulated expression of BH and upregulated expression of Caspase 14 and AQP3.The therapeutic effect of NB-UVB on chronic eczema may be partly attributed to the diminished expression of AQP3,Caspase 14 and BH.

8.
Chinese Journal of Dermatology ; (12): 255-258, 2012.
Artículo en Chino | WPRIM | ID: wpr-418562

RESUMEN

ObjectiveTo compare the accelerating effect of topical recombinant human epidermal growth factor (rhEGF) and recombinant bovine basic fibroblast growth factor (rb-bFGF) on wound healing after fractional CO2 laser therapy.MethodsTwenty male guinea pigs were included in this study.After hair removal and irradiation with fractional CO2 laser,the back of each guinea pig was divided into 4 regions to be topically treated with rhEGF of 10 μg/cm2 (rhEGF group),rb-bFGF of 262.51 IU/cm2 (rb-bFGF group),the combination of rhEGF and rb-bFGF (combination group),or normal saline (control group),twice daily until the healing of wound.Skin physiology parameters including elasticity index and melanin index were detected before the irradiation,7,14 and 28 days after the irradiation,and compared between the 4 groups by analysis of variance.Tissue specimens were obtained from 4 mice at the above time points and subjected to pathological examination for the observation of collagen fibers and quantification of fibroblasts.ResultsAfter fractional CO2 laser therapy,the crusts fall off completely in growth factor-treated regions,while partly in the control regions,within 3 to 7 days; the wounds healed completely in 14 to 28 days in all the groups,with the regenerating tissue being more tender and redder compared with the surrounding unirradiated tissue.The wound surface was smaller in area and redder in color in the 3 growth factor-treated groups than in the control group.At 28 days after the irradiation,the elasticity index was 262.29 ± 62.40 in the combination group,202.00 ± 65.62 in the rhEGF group,188.86 ± 35.02 in the rb-bFGF group,167.14 ± 42.49 in the control group.Statistical difference was observed in elasticity index,but not in skin melanin index among the 4 groups.Pathological examination showed a dense and organized arrangement of collagen fibers in the combination group but a sparse and disorganized arrangement of collagen fibers in the control group.ConclusionThe combined application of rhEGF and rbbFGF can accelerate the healing of wound and increase the elasticity of regenerating tissue after fractional CO2 laser therapy.

9.
Chinese Journal of Dermatology ; (12): 571-573, 2011.
Artículo en Chino | WPRIM | ID: wpr-417006

RESUMEN

A 27-year-old man presented with a 3-year history of persistent asymptomatic papules on the left chest and axirlary fossa. Multiple skin biopsies were performed and histopathology revealed mild acanthosis, extension of the dermal papilla, lichenoid lymphoid infiltrates in upper dermis. Some lymphoid cells migrated into the epidermis and formed Pautrier's microabscesses. Immunohistochemistry revealed that the infiltrating cells were positive for LCA, CD45RO, CD3, CD4 and CD8 (scattered), but negative for CD68 or CD30. Cutaneous laser confocal microscopy showed the shadow of scattered, oval or round, slightly refractive cells measuring 4-8 pm in diameter. A diagnosis of papular mycosis fungoides was made. The papules were softened with the lightening of lesional color after treatment with narrow-band ultraviolet B, topical fluticasone propionate cream and isotretinoin gel.

10.
Chinese Journal of Dermatology ; (12): 423-426, 2011.
Artículo en Chino | WPRIM | ID: wpr-416722

RESUMEN

Objective To investigate the dose-effect relationship between Q-switch ruby laser and skin pigmentation in Guinea pigs. Methods Ten Guinea pigs were included in this study, and the back of each pig was divided into 5 areas, negative control area receiving no UVB irradiation or laser treatment, positive control area receiving UVB irradiation but no laser treatment, low-, middle- and high-dose areas receiving UVB irradiation followed by the treatment with laser at an energy density of 1.5, 3.0 and 6.0 J/cm2 for 4, 2, and 1 session, respectively, with an interval of 1 week. Melanin content index (MCI) was determined, and confocal laser scanning microscopy (CLSM) and histopathology were performed to observe melanin granules and melanocytes in the skin tissue from Guinea pigs before the initial laser treatment, 2 and 4 weeks after the final laser treatment. Results The best response was observed in the low-dose areas, and there was a complete clearance of hyperpigmentation in these areas, which maintained 8 weeks without recurrence, while different degrees of skin pigmentation recurred in the middle- and high-dose areas. Moreover, the low-dose areas showed a significantly lower melanin content index (MCI) compared with the middle- and high-dose areas (F = 4.2,P < 0.05), together with a marked reduction in the extent of pigment deposition, melanin granules, melanocyte number and density. Conclusions The efficacy of Q-switched ruby laser on skin pigmentation in Guinea pigs is correlated with the energy density and treatment frequency, and, low intensity and high frequency are often associated with a better treatment outcome.

11.
Chinese Journal of Dermatology ; (12): 485-488, 2010.
Artículo en Chino | WPRIM | ID: wpr-388624

RESUMEN

Objective To analyze the relationship of melanocyte ultrastructure and expression of microphthalmia-associated transcription factor (MITF) as well as tyrosinase-related proteins (TRP) transcriptionally modulated by MITF to clinical types and duration of vitiligo.Methods Epidermal sheets were taken by suction blisters respectively from lesional,perilesional,and normal skin of 12 patients with vitiligo vulgaris (VV) and 8 with segmental vitiligo (SV).The duration of vitiligo varied from 3 to 300 months in these patients. Transmission electron microscopy was performed in 10 patients with vitiligo,including 6 cases of VV and 4 cases of SV.Epidermal melanocytes from normal skin of 20 patients were subjected to culture followed by Western blot to detect the expression level of MITF and some molecules transcriptionally modulated by MITF,including tyrosinase (TYR),TYR-related protein-1(TYRP1),and TYR-related protein-2 (TYRP2) in cultured melanocytes.Results Epidermal melanocytes were absent in lesional skin of 7 out of 10 patients observed for ultrastructural alterations,whereas melanocytes with reduced or absent melanin (melanosome) could accidently be seen in lesional skin of 1 patient with short-standing vitiligo and 2 patients with long-standing vitiligo.In perilesional skin.abnormal ultrastructure of melanocytes was found in 3 with a duration of vitiligo less than 15 months among 6 patients with VV,and in 1 out of 4 patients with SV.The down-regulated expression of MITF was consistent with that of TYR,TYRP1 and TYRP2 in cultured epidermal melanocytes from normal skin of patients with VV;in those from patients with SV,the down-regulated expression was observed only in MITF,while the expressions of TYR,TYRP1 and TYRP2 were nearly normal.Conclusion Differences may exist between VV and SV in the ultrastructure as well as mechanisms of transcriptional modulation by MITF in epidermal melanocytes.

12.
Chinese Journal of Dermatology ; (12): 758-761, 2010.
Artículo en Chino | WPRIM | ID: wpr-386268

RESUMEN

Objective To investigate the relationship between apoptosis in epidermal keratinocytes and efficacy of epidermal grafting. Methods Epidermal specimens were obtained from donor sites and depigmented area of 44 patients with vitiligo receiving epidermal grafting. The apoptosis in keratinocytes was determined by terminal deoxynucleotidyl transferase end-labeling (TUNEL) assay, and the expressions of caspase 3, 8, 9 as well as bcl-2 and P53 were evaluated by immunohistochemistry. Results As TUNEL assay showed, the number of apoptotic keratinocytes in epidermis from depigmented area differed significantly from that from donor sites.The expressions of caspase 3, 8 and 9 were mainly located in the membrane and cytoplasm of keratinocytes,and positive keratinocytes were predominately distributed in the middle and lower layer of the epidermis. Of the 44 patients, 19, 15 and 16 were positive for the expressions of caspase 3, 8 and 9 in the depigmented epidermis,respectively, and 9, 5 and 4 for those in the donor epidermis, respectively. P53 was expressed in neither donor epidermis nor depigmented epidermis, while Bcl-2 was weakly positive in donor epidermis and negative in depigmented epidermis. The number of apoptotic keratinocytes was higher in donor epidermis from patients failing to respond to the transplantation than in that from patients successfully treated by transplantation (15.83 ± 2.69 vs.9.24 ± 1.80, t = 10.96, P < 0.01 ). Conclusions There is an obvious apoptosis in keratinocytes from depigmented epidermis of patients with vitiligo, together with an increase in the expression of caspase 3, 8 and 9. The apoptosis in keratinocytes may be related to the efficacy of epidermal transplantation.

13.
Chinese Journal of Dermatology ; (12): 40-43, 2010.
Artículo en Chino | WPRIM | ID: wpr-391857

RESUMEN

Objective To assess the clinical features and diagnostic index of progressive macular hypomelanosis(PMH).Methods Eight patients with PMH were recruited into this study.Wood's lamp and in vivo confocal laser scanning microscopy(CLSM)were utilized to observe the lesions of all patients.Microbiological culture of lesion specimens from 2 patients was performed.Tissue specimens from 4 patients underwent immunohistochemieal staining with anti-S-100 and anti-TRP-1 antibodies for the detection of melanocyte quantity.Electron microscopy wag utilized to observe ultrastructural features of lesions.Primary culture of melanocytes was carried out with lesional epidermis.Resnits Under Wood's lamp.the lesions of PMH showed punctiform red fluorescence.CLSM revealed complete pigmented tings in lesions with decreased melanin granules compamd with those surrounding normal skin.Microbiological culture grew red fluorescence-producing,gram-positive bacillus which was identified as Propionibacterium acnes.Immunohistochemistry showed no significant difference in the number of S-100-postive cells or TRP-1-positive cells per high power field (× 400)between lesions and surrounding normal skin (8.25±0.96 vs 8.75±1.71,4.25±0.96 vs 4.50±1.29,both P>0.05).Ultrastructural studies showed a large reduction in the number of type Ⅳ melanosomes in lesions of PMH,along with numemus membrane bound bodies and clusteredly distributed,small type Ⅱ-Ⅳ melanosomes.Melanocytes,with morphological similarity to normal melanocytes,were successfully isolated from the lesional tissue,cuhured and identified.Conclusion A primary diagnostic criteria is pro-posed for PMH according to the clinical and experimental studies.

14.
Journal of Biomedical Engineering ; (6): 736-740, 2010.
Artículo en Chino | WPRIM | ID: wpr-230794

RESUMEN

This study was aimed to evaluate the effects of different echo time (TE) on the liver fat quantification using proton magnetic resonance spectroscopy (1H-MRS). Liver 1H-MRS was performed on 24 adult male wistar rats on a 1.5 T superconductor MR scanner. Spectrums were collected with a TR of 1500 ms and different TE of 35, 45, 55, 65, 75, 85, 95, 105, 144 ms, respectively. The water and lipid peaks, baseline of the spectrum and lipid to water ratio were evaluated. With the increment of TE, the amplitude and integrated area of the water and lipid peaks decreased, and the baseline of the spectrum and the lipid to water ratio became unstable. The lipid to water ratio determined by 1H-MRS was highly correlated with the liver fat content determined by pathological analysis at TE between 35 and 55 ms (r > 0.9) and poorly to moderately correlated at TE > or =65 ms (r < 0.9). The results indicated that long TE would compromise the liver fat quantification using 1H-MRS, and therefore short TE was strongly recommended for liver fat quantification.


Asunto(s)
Animales , Masculino , Ratas , Tejido Adiposo , Metabolismo , Lípidos , Hígado , Metabolismo , Espectroscopía de Resonancia Magnética , Métodos , Ratas Wistar , Análisis Espectral
15.
Chinese Journal of Medical Imaging Technology ; (12): 369-371, 2010.
Artículo en Chino | WPRIM | ID: wpr-472482

RESUMEN

Objective To observe the effect of full width half max (FWHM) on spectra signal-to-noise ratio (SNR), NAA/Cr, Cho/Cr and water suppression at 3.0T MR. Methods GE Signa Excite HD 3.0T MR scanner with 8 channel phrased-array head and neck coil was used. The respective study of liver 1H-MRS was performed using PRESS sequence. A total of 49 spectrums were obtained with parameters of TR 1500 ms, TE 30 ms, NSA 128. FWHM and water suppression were recorded automatically and the subjects were divided into better shimming group (FWHM<10 Hz) and worse shimming group (FWHM≥10 Hz). Independent t test was used to analyze the Cr_SNR, NAA/Cr, Cho/Cr, water suppression and volume of interest (VOI). Results Compared with worse shimming group, better shimming group could provide better Cr_SNR (t=5.976, P<0.001), higher NAA/Cr (t=2.469, P=0.017), lower Cho/Cr (t=-4.460, P<0.001) and smaller VOI (t=3.862, P<0.001). Conclusion When single voxel proton spectroscopy of head is adopted with 3.0T MR, small VOI is easy to achieve effective shimming, and better shimming is helpful to improve SNR, the ratio of main metabolites as well as water suppression.

16.
Chinese Journal of Medical Imaging Technology ; (12): 571-573, 2010.
Artículo en Chino | WPRIM | ID: wpr-472427

RESUMEN

Objective To evaluate the effect of intravenous Gd-DTPA on 3.0T proton MR spectroscopy (MRS) water suppression and shimming. Methods Prospective study of proton MRS was performed with GE Signa Excite HD 3.0T system and eight-channel phased-array coils with PRESS sequence (head, liver and kidney, respectively). Routine auto prescan program was operated to record full width half maximum (FWHM) and water suppression (WS%). Routine scan was performed after injection of Gd-DTPA, then prescan program was reoperated to record FWHM and WS%. The data of FWHM and WS% in head, liver and kidney were compared between before and after injection of Gd-DTPA with the Wilcoxon matched pairs signed test. Results WS% of spectroscopy of head and liver after administration of Gd-DTPA decreased significantly (T_+=12, T_-=66, P=0.02; T_+=0, T_-=45, P=0.007). The effect of shimming of kidney after administration of Gd-DTPA was poor (T_+=0, T_-=435, P<0.001) and WS% of spectroscopy of kidney after administration of Gd-DTPA decreased significantly (T_+=0, T_-=435, P<0.001). Conclusion WS% of spectroscopy in head, liver and kidney can be impacted negatively by Gd-DTPA. Gd-DTPA has great influence on shimming of spectroscopy of kidney, but has little influence on shimming of spectroscopy of head and liver. It is better to acquire MRS data before administration of contrast medium in kidney.

17.
Journal of Practical Radiology ; (12): 571-574, 2010.
Artículo en Chino | WPRIM | ID: wpr-402741

RESUMEN

Objective To evaluate the advantages of MR LAVA multi-phase dynamic contrast enhancement in abdominal MRI.Methods 42 cases which clinically suspected liver lesions and 15 normal volunteers underwent MRI examination,including routine T_1WI and T_2WI scan,T_1W 2D and 3D FSPGR,LAV A multi-phase contrast enhancement.The detecting rates of 2D,3D and LAVA images were analysed and the signal noise ratio(SNR)of the liver and spleen was observed.Results 68 lesions were detected by LAVA sequence,the detecting rate was 100%,the accurate rate of diagnosis was 95.6%(65/68),while the detecting rates of the lesions were 91.2%(62/68)and 89.7%(61/68)with 3D T1W FSPGR and 2D T1W FSPGR,respectively,the accurate rates in diagnosing the lesions were 76.5%(52/68)and 70.6%(48/68)with 3D and 2D sequences,respectively.The SNR of liver,spleen of 15 normal volunteers were:29.68±2.31 in liver,36.21 ±3.67 in spleen at LAVA plain scan,46.21 ±5.32 in liver,58.75±4.68 in spleen at 2D T_1W FSPGR,19.79±2.23 in liver,23.63±2.14 in spleen at 3D T_1W FSPGR,41.75±5.13 in liver,57.96±6.13 in spleen at LAVA contrast enhancement,56.33±5.63 in liver,63.21±5.32 in spleen at 2D contrast enhancement,29.05±4.68 in liver,46.37±5.17 in spleen at 3D contrast enhancement sequence.Conclusion LAVA multi-phase dynamic contrast enhancement is more predominant than T1W 2D and 3D and 3D FSPGR in displaying the lesions and blood vessels of liver.

18.
Chinese Journal of Radiology ; (12): 739-742, 2009.
Artículo en Chino | WPRIM | ID: wpr-394076

RESUMEN

Objective To characterize the clinical factors which influence water suppression and auto-shimming line width for liver 3.0 T 1H-MRS.Methods Fifty-seven cases with liver 1H-MR spectroscopy(1H-MRS) were retrospectively studied, including chronic type B hepatitis (n=5), fatty liver (n=14), chronic type B hepatitis combining fatty liver (n=3) and normal situation (n=35).Independent t test was used to characterize the difference of general condition (height, weight, body mass index etc.) between different water suppression effect groups and between different shimming effect groups.Using Chi-square test to analyze whether water suppression rate and auto-shimming line width between fatty liver groups and non-fatty liver exist significance difference .Results By comparing WS ≥90% (n=47)group with WS < 90% (n=10) group, the former showed smaller average height[(164.7±8.0) and (170.5±3.7) cm respectively], weight[(61.8±10.4) and (73.4±5.4) kg respectively], BMI [(22.7±3.2) and (25.2±1.3)kg/m2 respectively]and LW[(17.7±3.7)and(24.6±6.3) Hz respectively]than the latter (t=-3.488,-3.415,-4.002 and-3.327, P < 0.05).By comparing LW 20 Hz (n=41) group with LW 20 Hz (n=16) group, the former showed better water suppression rate [(93.0±2.7)% and (86.1±8.5)% respectively]than the latter(t=3.213,P <0.05), whereas larger weight[(62.2±11.6) and (68.1±6.1)kg respectively]and BMI[(22.8±3.4) and (24.2±1.9)kg/m2 respectively](t=-2.516,-2.024,P <0.05).LW≤20 Hz in the fatty liver and non-fatty liver group was 7/17 and 34/40, respectively (X2=11.347, P < 0.05).WS < 90% in the fatty liver and non-fatty liver group was 10/17 and 0/44, respectively (X2=28.536, P < 0.05) .Conclusion Hepatic steatosis exerts an adverse effect in water suppression and shimming.

19.
Chinese Journal of Radiology ; (12): 1191-1195, 2009.
Artículo en Chino | WPRIM | ID: wpr-392306

RESUMEN

Objective To characterize the effect of the ~1H-MRS scan parametem, including the type of coil, TE,NSA and VOI, on shimming, water suppression, spectral signal to noise ratio(SNR)and the stability of the baseline of liver in vivo. Methods ~1H-MRS of liver in vivo was performed prospectively on GE Signa Excite HD 3.0 T system in 46 volunteers. Point-resolred spectroscopy(PRESS)sequence with built-in body coil and eight-channel torso phased-array coils was applied. After the localized scan,the first PRESS sequence with a TR of 1500 ms,TE of 30 ms. VOI of 2 cm×2 cm×2 cm and NSA of 64 times was acquired using eight-channel torso phased-array coils.(The first PRESS sequence parametem was deemed as A).Then,the sequence was repeated with alteration of the three parameters including the type of coil,TE and size of VOI.(Changed parameters deem as B).The data were analyzed with the Wilcoxon matched pairs signed test.0 mark:A is similar to B,1 mark:A better than B,-1 mark:A worse than B.Results SNR(-1 mark 0 pair,0 mark 1 pair,1 mark 10 pair,Z=-3.162,P=0.002)was better in data(n=11)with eight-channel torso phased-array coils(A)than that with the built-in body coil(B),but the autoshimming line width with eight-channel torso phased-array coils were inferior to those with built-in body coil (-1 mark 8 pair,0 mark 2 pair,1 mark 1 pair,Z=-2.511,P=0.012).SNR was better in data(n=13)with TE of 30 ms(A)than that at the sequence with TE of 90 ms(B)(-1 mark 2 pair,0 mark 0 pair,1 mark 11 pair,Z=-2.496,P=0.013).whereas baseline stability was,poorer in the former(-1 mark 10 pair,0 mark 2 pair,1 mark 1 pair,Z=-2.333,P=0.020).SNR at the sequence(n=10)with VOI of 2 cm×2 cm×3 cm(B)was better(-1 mark 6 pair,0 mark 4 pair,1 mark 0 pair,Z=-2.449,P=0.014)than that at the sequence(n=29)with VOI of 2 cm ×2 cm × 2 cm(A),but poorer(-1 mark 0 pair,0 mark 5 pair,1 mark 5 pair,Z=-2.041,P=0.041)auto-shimming line width was shown. By comparison the sequences with NSA of 128 times(B)and NSA of 64 times(A),the former could provide better spectrum SNR(-1 mark 21 pair,0 mark 7 pair,1 mark 1 pair,Z=-4.264,P=0.000).Conclusion It is more easy to achieve a homogeneous bo magnetic field using a small size of VOI and builtin body coli.The sequence with VOI of 2 cm ×2 cm ×3 cm.NSA of 128 times is recommended for clinical use. Increase VOI and NSA are helpful to improve SNR. Longer TE is helpful to improve baseline stability.

20.
Chinese Journal of Dermatology ; (12): 371-373, 2008.
Artículo en Chino | WPRIM | ID: wpr-400647

RESUMEN

In the first case, a 15-year-old girl presented with recurrent multiple erythematous edema,bullae and ulceration on the face and extremities for 3 years, which had developed into plaques and nodules on the face and trunk for 6 months. Histology revealed angiocentric and angiodestructive infiltrates with medium-sized atypical lymphoid cells positive for LCA, CD45RO, CD56 and EBV staining throughout the dermis. The patient was diagnosed with extra NK/T-cell lymphoma, nasal-type. She subsequently had a rapid downhill clinical course with resistance to systemic chemotherapy, and died one month later. In the second case, a 44-year-old male was admitted to the hospital with progressive infiltrated mass on the right waist for 1 year, and a 4-month-history of lymphadenectasis. Histologically, there was a massive and dense infiltrate with middle and large-sized, CD4 and CD56-positive lymphoblastics throughout the dennis and subcutaneous tissue. A diagnosis of blastic NK-cell lymphoma was made. The patient was managed with surgical excision followed by systemic chemotherapy. He had been followed up and free of relapse till the time of this writing.CD56 positive cutaneous lymphoproliferative disorders appear to be highly invasive.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA