Differentiation of focal liver lesions using three-dimensional ultrasonography: Retrospective and prospective studies

AIM: To differentiate focal liver lesions based on enhancement patterns using three-dimensional ultrasonography (3D US) with perflubutane-based contrast agent.METHODS: Two hundred and eighty two patients with focal liver lesions,including 168 hepatocellular carcinomas (HCCs),63 metastases,40 hemangiomas and 11 focal nodular hyperplasias (FNHs),were examined by 3D US with perflubutane-based contrast agent.Tomographic ultrasound images and sonographic angiograms were reconstructed.Among 282 lesions,enhancement patterns of 163 lesions between January 2007 and October 2007 were analyzed retrospectively.Then from November 2007 to May 2008,compared with contrast-enhanced (CE) 2D US,CE 3D US was performed on 119 lesions for prospective differential diagnosis.Sensitivity,specificity,area under receiver operating characteristic curve (Az) and inter-reader agreement were assessed.RESULTS: With the tridimensional view,dominant enhancement patterns were revealed as diffuse enhancement or peripheral ring-like enhancement,followed with washout change for HCCs or metastases,respectively,and peripheral nodular enhancement or diffuse enhancement with spoke-wheel arteries,followed by persistent enhancement for hemangiomas or FNHs,respectively.At CE 3D US,the prospective differentiation of lesions showed sensitivity 92% (mean for two readers),specificity 91% and Az value 0.95 for HCCs,84%,97%,and 0.95 for metastases,91%,98%,and 0.98 for hemangiomas and 80%,99%,and 0.99 for FNHs,respectively,while good to excellent inter-reader agreement was achieved.No significant difference exists between prospective diagnosis accuracy at CE 3D US and that at CE 2D US.CONCLUSION: CE 3D US provides a spatial perspective for liver tumor enhancement,and could help in differentiating focal liver lesions.

Real-time Three-Dimensional Color Doppler Flow Imaging： An Improved Technique for Quantitative Analysis of Aortic Regurgitation

The recently introduced real-time three-dimensional color Doppler flow imaging （RT-3D CDFI） technique provides a quick and accurate calculation of regurgitant jet volume （RJV） and fraction. In order to evaluate RT-3D CDFI in the noninvasive assessment of aortic RJV and regurgitant jet fraction （RJF） in patients with isolated aortic regurgitation, real-time three-dimensional echocardiographic studies were performed on 23 patients with isolated aortic regurgitation to obtain LV end-diastolic volumes （LVEDV）, end-systolic volumes （LVESV） and RJV, and then RJF could be calculated. The regurgitant volume （RV） and regurgitant fraction （RF） calculated by two-dimensional pulsed Doppler （2D-PD） method served as reference values. The results showed that aortic RJV measured by the RT-3D CDFI method showed a good correlation with the 2D-PD measurements （r= 0.93, Y=0.89X＋ 3.9, SEE= 8.6 mL, P〈0.001 ）; the mean （SD） difference between the two methods was - 1.5 （9.8） mL. % RJF estimated by the RT-3D CDFI method was also correlated well with the values obtained by the 2D-PD method （r=0.88, Y=0.71X＋ 14.8, SEE= 6.4 %, P〈0. 001）; the mean （SD） difference between the two methods was -1.2 （7.9） %. It was suggested that the newly developed RT-3D CDFI technique was feasible in the majority of patients. In patients with eccentric aortic regurgitation, this new modality provides additional information to that obtained from the two-dimensional examination, which overcomes the inherent limitations of two-dimensional echocardiography by depicting the full extent of the jet trajectory. In addition, the RT-3D CDFI method is quick and accurate in calculating RJV and RJF.

Prenatal assessment of normal fetal pulmonary grey-scale and lung volume by three-dimensional ultrasonography

Objective To quantitatively analyze the fetal lung echo and right lung volume in the third trimester by real-time three-dimensional ultrasound(3-D US)and evaluate the feasibility of fetal lung maturity.Methods A total of 732 women with normal singleton pregnancies between 28 and 42 weeks of gestation underwent ultrasound examination.The 3-D US equipment with a 3.5-5 MHz transabdominal transducer was used for the fetal biometric measurement.The echogenicity ratio between fetal lung and liver was compared.The fetal lung volume was calculated by the rotational multiplanar technique for volume measurement(VOCAL).Results The right fetal lung volume increased with the increase of gestational age with a linear positive correlation(r=0.884,P<0.01).After 34 weeks,the echogenicity ratio of fetal lung to liver was more than 1.1.Conclusion The echogenicity of lung/liver and fetal lung volume could be used as normal fetal predictable indicators for fetal lung maturity.

Prenatal diagnosis of isolated lateral facial cleft by ultrasonography and three-dimensional printing:A case report

BACKGROUND Lateral facial clefts are atypical with a low incidence in the facial cleft spectrum.With the development of ultrasonography(US)prenatal screening,such facial malformations can be detected and diagnosed prenatally rather than at birth.Although three-dimensional US(3DUS)can render the fetus'face via 3D reconstruction,the 3D images are displayed on two-dimensional screens without field depth,which impedes the understanding of untrained individuals.In contrast,a 3D-printed model of the fetus'face helps both parents and doctors develop a more comprehensive understanding of the facial malformation by creating more interactive aspects.Herein,we present an isolated lateral facial cleft case that was diagnosed via US combined with a 3D-printed model.CASE SUMMARY A 31-year-old G2P1 patient presented for routine prenatal screening at the 22nd wk of gestation.The coronal nostril-lip section of two-dimensional US(2DUS)demonstrated that the fetus'bilateral oral commissures were asymmetrical,and left oral commissure was abnormally wide.The left oblique-coronal section showed a cleft at the left oral commissure which extended to the left cheek.The results of 3DUS confirmed the cleft.Furthermore,we created a model of the fetal face using 3D printing technology,which clearly presented facial malformations.The fetus was diagnosed with a left lateral facial cleft,which was categorized as a No.7 facial cleft according to the Tessier facial cleft classification.The parents terminated the pregnancy at the 24th wk of gestation after parental counseling.CONCLUSION In the diagnostic course of the current case,in addition to the traditional application of 2D and 3DUS,we created a 3D-printed model of the fetus,which enhanced diagnostic evidence,benefited the education of junior doctors,improved parental counseling,and had the potential to guide surgical planning.

Clinical Application of Surface Mode on Three-dimensional Ultrasonography: A Preliminary Study

To investigate the methodology and evaluate the clinical value of surface mode on three- dimensional ultrasonography (3DUS) in static anatomical structures, 62 patients with various diseases were studied. The equipment used here was Voluson 530D 3DUS imaging system and 3D volume trahsducer with frequency being 3. 0-5. 0 MHz. The 3DUS rendering method was surface mode. The results showed that: 1 ) Surface mode of 3DUS could demonstrate clearly the anatomical characteristics of the region-of-interest (ROI) and the inner wall of lesions or organs that contained fluid. The anatomic details, such as location, size, shape, and number of the ROI, could be visualized intuitively; 2) The outer anatomic features (e. g. contour, edge, configuration, etc. ) of some organs or lesions surrounded by fluid could be displayed clearly. It could be concluded that surface mode on 3DUS could provide more diagnostic information than two-dimensional ultrasonography (2DUS) in some cases and could served as a beneficial supplement to ZDUS in clinical practice.

The value of color Doppler ultrasonography in monitoring normal orthotopic liver transplantation and postoperative complications

OBJECTIVE: To assess the value of color Doppler ultrasonography in monitoring normal orthotopic liver transplantation and postoperative complications. METHODS: Forty-one patients after orthotopic liver transplantation were examined by using color Doppler flow imaging to observe the hepatic blood flow and change of ultrasonography of the hepatic parenchyma and bile duct. The measured indexes included maximum blood flow velocity, time-average blood flow velocity (TAV), resistance index (RI) and diameter of the bile duct. RESULTS: Among 41 patients, 17 (41.5%) suffered from liver transplant rejection. Of the 17 patients, 13 (76.4%) showed decrease of TAV of the portal vein, 15 (88.25%) low-amplitude single-phase serrated wave or negative biphasic wave of the hepatic vein, 9 (52.9%) increased hepatic arterial RI, and 5 (29.4%) slightly dilated bile duct. Sonography showed disappearance of the hepatic artery blood flow around the portal vein in 5 (12.2%) of the 41 patients with hepatic artery thrombosis in the postoperative period. Slight dilatation of the intrahepatic bile duct was found in 3 (7.3%) of the 41 patients in the early postoperational period and it normalized within 2 weeks. Ultrasonography of 20 patients (48.8%) revealed a visible dilatation of the intrahepatic bile duct, which was worsening gradually. The causes of bile duct dilatation included biliary stricture in 2 patients (10%), stone in 15 patients (75%) and others in 3 patients (15%). CONCLUSIONS: Color Doppler ultrasonography is valuable for monitoring normal liver transplantation and postoperative complications.

Different hemodynamic responses by color Doppler ultrasonography studies between sildenafil non-responders and responders

Aim： To determine if there are different penile hemodynamic patterns between sildenafil non-responders and responders by using color Doppler ultrasonography. Methods： A total of 69 erectile dysfunction （ED） patients aged 22-79 years were enrolled into the present study. Thirty-eight （55.1%） men with ED who did not respond to four attempts of treatment with 100 mg sildenafil after re-education were classified as sildenafil non-responders. A com- bination of three vasodilator drugs, 1.25 mg papaverine, 0.4 mg phentolamine and 5 ug prostaglandin E1, was given by intracavernous injection before penile Doppler ultrasonography was carried out. The erectile response to intracavernous injection and vascular parameters including peak systolic velocity （PSV）, resistance index （RI）, end diastolic velocity （EDV） and cavernosa artery diameter （CD） were measured and the results between sildenafil nonresponders and responders were compared. Results： No statistical difference in vascular parameters measured by Doppler ultrasonography studies between non-responders and responders was noted. Sildenafil non-responders had a poorer penile rigidity response to intracavernous injection than responders （P 〈 0.05）. Among patients with adequate PSV （〉 30 cm/s） and abnormal EDV （〉 5 cm/s）, individuals in the non-responder group had fewer positive responses to intracavernous vasodilator injection than in the responder group （35.3% vs. 72.2%, P 〈 0.05）. Advanced age and comorbidity with diabetes mellitus were significantly associated with sildenafil non-response （P 〈 0.05）. Conclusion： Sildenafil non-responders were characterized by a poorer penile rigidity response to intracavernous injection and had an associated impaired veno-occlusive mechanism. Advanced age and comorbidity with diabetes mellitus were two common factors associated with non-response.

Use of color Doppler ultrasonography in the diagnosis of anomalous connection in pancreatobiliary disease

AIM: To estimate the detectability of anomalous connection in pancreatobiliary disease (ACPBD) cases, measuring gallbladder wall blood flow (GWBF).METHODS: In the retrospective study, we enrolled 42subjects with gallbladder wall thickening. GWBF velocity was determined as an average value of the peak velocity of color signals on the gallbladder wall, three times in each case. Based on the findings on endoscopic ultrasonography (EUS) or endoscopic retrograde cholangiopancreatography (ERCP), the 42 subjects were divided into 11 cases with ACPBD and 31 cases without ACPBD. In the prospective study, the subjects were 92 cases with gallbladder wall thickening. Using the cut-off level of the flow velocity obtained in the retrospective study, the usefulness of measuring GWBF velocity in diagnosing ACPBD was evaluated.RESULTS: In the retrospective study, imaging of GWBF was obtained in 40 of the 42 subjects. The mean GWBF velocity of the ACPBD cases was 29.4±3.9 cm/s(mean±SD), which was significantly different (P＜0.0001;95% CI 5.48-13.2) from that of the without ACPBD cases(20.1±5.9 cm/s). Based on this result, we prepared a receiver operating characteristic curve, and the cut-off level appropriate for diagnosing ACPBD was estimated to be 25 cm/s. In the prospective study, GWBF was detected in 86 of the 92 subjects. Based on the EUS or ERCP findings, the 92 subjects were divided into 15 cases with ACPBD and 77 cases without ACPBD. When a cut-off level of 25 cm/s was employed, ACPBD could be diagnosed with a sensitivity of 87.0% (13/15) and a specificity of87.3% (62/71).CONCLUSION: Measurement of GWBF velocity, which is less invasive and provides objective values, is very useful for diagnosing ACPBD prior to the development of malignant tumors in cases with gallbladder wall thickening.

COLOR DOPPLER ULTRASONOGRAPHY APPEARANCES OF RENAL VEIN THROMBOSIS AND ITS DIAGNOSTIC VALUE

Objective To evaluate color Doppler ultrasonography (CDU) appearances of renal vein thrombosis (RVT) and its diagnostic value.Methods Ten patients with RVT were analyzed retrospectively. Renal structure, distributions of intrarenal flow signals, echogenicity, and flow fullness in main renal veins were observed with CDU. Resistance index (RI) was recorded from the waveforms of segmental or interlobar renal artery.Results Ten kidneys in nine patients were confirmed to have thrombus within the main renal veins, and one patient was confirmed to have thrombus within the small intrarenal veins. The appearances of the main renal vein thrombosis included full of solid echogenicity or strip echogenicity and complete or partial filling defect within the main renal veins, and absent or a few intrarenal venous flow signals in 70% of kidneys involved. The appearances of intrarenal vein thrombosis included obscure renal structure and no venous flow signal within the involved part of the kidneys. Reverse diastolic flow in the intrarenal artery had only a sensitivity of 36% (4/11); in other 7 kidneys without intrarenal arterial reverse diastolic flow, increased RI (mean, 0.84; range, 0.74-0.96) was found.Conclusion CDU is helpful for rapid clinical diagnosis and follow-up of RVT, and therefore can be the first imaging modality of choice for RVT.

Pitfalls and sources of error of color duplex ultrasonography in detecting deep vein thrombosis of proximal lower extremities

Purpose To analyze the sources of errors and discuss the techniques to eliminate pitfalls in detecting deep vein thrombosis (DVT) of the proximal lower extremities with color duplex ultrasonography (CDUS). Methods Sixty-eight cases with initial and repeat venous CDUS of the proximal lower extremities were retrospectively reviewed. The repeat was done within 24 hours after initial CDUS scanning. Comparing repeated images to initial ones, the pitfalls and sources of error in CDUS of the proximal lower extremities were discussed. Results In total 68 repeat studies, there were 62 results as same as initials and 4 cases of false negative DVT and 2 cases of false positive DVT. Conclusion Venous CDUS in detecting DVT is observer dependent. Some pitfalls and errors can be eliminated and corrected with proper scan techniques. CDUS is the most valuable imaging modality for assessing suspected DVT in the proximal lower extremities.

A study of the hypoechoic hypertrophic lesions and hypoechoic cancer lesions in hypertrophic prostate inner glands with transrectal color doppler ultrasonography

Objective: To observe the sonographic and hemodynamic features of hypoechoic hypertrophic lesions and hypoechoic cancer lesions in the hypertrophic prostate inner glands, in order to raise the accuracy of early diagnosis rate for prostate cancer. Methods: 31 cases of hypoechoic hypertrophic lesions and 18 cases of hypoechoic cancer lesions in the hypertrophic prostate inner glands were observed by transrectal ultrasonography and comparatively analyze the shape, edge and the systolic peak velocity (Vs) , resistance index (RI) and pulsatility index (PI) of the lesions. Results: In contrast with hypertrophic group, the cancer group presented irregular shape and unclear edge, and obviously higher Vs, RI and PI. Conclusion: The sonographic appearance and Vs. RI. PI have important value in distinguishing hypoechoic hypertrophic lesions and hypoechoic cancer lesions in the hypertrophic prostate inner glands.

Value of identifying and diagnosing mammary carcinoma and non-lactation mastitis lump by color Doppler ultrasonography

Objective: To evaluate the value of identifying and diagnosing mammary carcinoma and non-lactation mastitis lump (NLM) by multicolor Doppler ultrasonography. Methods: We compared and analyzed the examination results of 69 cases of mammary carcinoma proved by surgical pathology and 22 cases of NLM before surgery by multicolor Doppler ultra-sonography. Results: The detection rates of mammary carcinoma and NLM focus by ultrasonic examining were 100%. The shape, envelope, foul line, blood stream between sound and image of two diseases were similar. Of the two diseases, the representation with slight calcification in lump, lower echo in low echo, bloodstream distribution and resistance were different. Conclusion: By analyzing the sound and image representation of mammary lump, we find color Doppler ultrasonography has significant value in identifying and diagnosing mammary carcinoma and non-lactation mastitis lump.

Radiation induced renal arterial stenosis detected by color duplex ultrasonography: case report

Renal artery stenosis as a complication from radiation therapy is not common, but it is life threatening and needs to be corrected urgently in order to prevent renal failure even losing kidney. The diagnostic criteria of renal artery stenosis in the adults by color duplex ultrasonography have been established, which may play an important role in screening radiation induced renal artery stenosis.

Graves' Disease Thyroid Color-Flow Doppler Ultrasonography Assessment: Review Article

Graves’ disease, as known today, is an autoimmune, diffuse, chronic disease of thyroid gland, as described by Robert Graves in 1835. It presents genetic predisposition and unknown etiology evidence, which is influenced in its development by several factors, including environment (dietary iodine intake, stress, drugs and infections). The disease is characterized by one or more changes: hyperthyroidism, goiter, ophthalmopathy, skin changes and pretibial myxedema, around 5% less common, and other symptoms 90% to 95%. One of the most relevant clinical practice aspects in Graves’ disease patients management is to distinguish Graves’ disease in initial phase, from other types of destructive thyrotoxicosis, in addition to evaluate therapeutic methods and efficient follow up, as well as predict early recurrence or remission of disease. Scintigraphy with pertechnetate (99 mTc) and TSH levels dosage are considered the choice for this purpose. However, they present some technical difficulties, as they are not widely available and have contraindications. In this scenario, thyroid color-flow doppler ultrasonography (US Doppler) presents a viable alternative, as a widely available, low cost, non-invasive and radiation free method, providing initial diagnosis and patients with Graves’ disease follow up. In adittion, this method is used in differential diagnosis with other causes of thyrotoxicosis in the early stage.

18 MHz彩色多普勒超声检查对黄斑前膜的临床诊断价值

目的:探讨18 MHz彩色多普勒超声对黄斑前膜的诊断价值。方法:收集2020-01/2022-01期间在我院经眼底检查拟诊白内障和玻璃体混浊的患者44例80眼,分别通过光学相干断层扫描法(OCT)与18 MHz彩色多普勒超声对患眼进行检查,比较18 MHz彩色多普勒超声与OCT对黄斑前膜诊断敏感度、特异性、准确度的差异。结果:经18 MHz彩色多普勒超声检测80眼中,62眼为黄斑前膜,18眼为非黄斑前膜;经OCT确诊确实为黄斑前膜的54眼,非黄斑前膜的13眼,漏诊5眼,误诊8眼;18 MHz彩色多普勒超声与OCT诊断一致性较高(Kappa=0.892,P<0.05);18 MHz彩色多普勒超声检测黄斑前膜敏感性为92%,特异性为62%,漏诊率为8%,误诊率为38%,正确率为84%;与OCT检测相比,18 MHz彩色多普勒超声检测特异性、正确率、阳性预测准确率、阴性预测准确率降低,误诊率升高(均P<0.05),诊断敏感性与漏诊率比较无差异(均P>0.05)。结论:18 MHz彩色多普勒超声对黄斑前膜病变具有一定鉴定价值,与OCT检验具有一致性。

Portalsystemic hemodynamic changes in chronic severe hepatitis B: An ultrasonographic study

AIM： To evaluate portalsystemic hemodynamic changes in chronic severe hepatitis B. METHODS： Hemodynamic parameters included portal vein diameter （PVD）, portal vein peak velocity （PVPV）, portal vein volume （PW）, spleen length （SPL）, spleen vein diameter （SPVD）, spleen vein volume （SPW） and umbilical vein recanalization. They were measured by Color Doppler ultrasonography in 36 patients with chronic severe hepatitis B, compared with 51 normal controls, 61 patients with chronic hepatitis B, 46 patients with compensable cirrhosis, and 36 patients with decompensable cirrhosis. RESULTS： In the group of chronic severe hepatitis B, PVD （12.38 ± 1.23 mm） was significantly different from the normal control, compensable cirrhosis and decompensable cirrhosis groups （P = 0.000-0.026）, but not significantly different from the chronic hepatitis group. PVPV （16.15 ± 3.82 cm/s） dropped more significantly in the chronic severe hepatitis B group than the normal control, chronic hepatitis B and compensable cirrhosis groups （P = 0.000-0.011）. PW （667.53 ± 192.83 mL/min） dropped significantly as compared with the four comparison groups （P = 0.000-0.004）. SPL （120.42 ± 18.36 mm） and SPVD （7.52 ± 1.52 mm） were longer in the normal control and chronic hepatitis B groups （P = 0.000-0.009）, yet they were significantly shorter than those in the decompensable cirrhosis group （P = 0.000）. SPW （242.51 ± 137.70 mL/min） was also lower than the decompensable cirrhosis group （P = 0.000）. The umbilical vein recanalization rate （75%） was higher than the chronic hepatitis B and compensable cirrhosis groups. In the course of progression from chronic hepatitis to decompensable cirrhosis, PVD, SPL and SPVD gradually increased and showed significant differences between every two groups （P = 0.000-0.002）. CONCLUSION： Patients with chronic severe hepatitis B have a tendency to develop acute portal hypertension, resulting in significantly reduced portal vein perfusion, Observation of the portalsystemic hemodynamic changes may be contributed to the disease progression of chronic liver disease.

Color Doppler sonography and angioscintigraphy in hepatic Hodgkin's lymphoma

AIM： To estimate the characteristics of Color Doppler findings and the results of hepatic radionuclide angiography （HRA） in secondary Hodgkin＇s hepatic lymphoma. METHODS： The research included patients with a diagnosis of Hodgkin＇s lymphoma with metastatic focal lesions in the liver and controls. Morphologic characteristics of focal liver lesions and hemodynamic parameters were examined by pulsed and Color Doppler in the portal, hepatic and splenic veins were examined. Hepatic perfusion index （HPI） estimated by HRA was calculated. was observed. Lesions were mostly hypoechoic and mixed, solitary or multiple. Some of the patients presented with dilated splenic veins and hepatofugal blood flow. A pulse wave was registered in the centre and at the margins of lymphoma. The average velocity of the pulse wave was higher at the margins （P 〉 0.05）. A continuous venous wave was found only at the margins of lymphoma. There was no linear correlation between lymphoma size and velocity of pulse and continuous wave （r = 390, P 〈 0.01）. HPI was significantly lower in patients with lymphomas than in controls （P 〈 0.05）, pointing out increased arterial perfusion in comparison to portal perfusion. CONCLUSION： Color Doppler ultrasonography is a sensitive method for the detection of neovascularization in Hodgkin＇s hepatic lymphoma and estimation of its intensity. Hepatic radionuclide angiography can additionally help in the assesment of vascularisation of liver lesions.

Endoanal ultrasonography in fecal incontinence: Current and future perspectives

Fecal incontinence has a profound impact in a patient's life, impairing quality of life and carrying a substantial economic burden due to health costs. It is an underdiagnosed condition because many affected patients are reluctant to report it and also clinicians are usually not alert to it. Patient evaluation with a detailed clinical history and examination is very important to indicate the type of injury that is present. Endoanal ultrasonography is currently the gold standard for sphincter evaluation in fecal incontinence and is a simple, well-tolerated and non-expensive technique. Most studies revealed 100%sensitivity in identifying sphincter defect. It is better than endoanal magnetic resonance imaging for internal anal sphincter defects, equivalent for the diagnosis of external anal sphincter defects, but with a lower capacity for assessment of atrophy of this sphincter.The most common cause of fecal incontinence is anal sphincter injury related to obstetric trauma. Only a small percentage of women are diagnosed with sphincter tears immediately after vaginal delivery, but endoanal ultrasonography shows that one third of these women have occult sphincter defects. Furthermore, in patients submitted to primary repair of these tears, ultrasound revealed a high frequency of persistent sphincter defects after surgery. Three-dimensional endoanal ultrasonography is currently largely used and accepted for sphincter evaluation in fecal incontinence, improving diagnostic accuracy and our knowledge of physiologic and pathological sphincters alterations. Conversely,there is currently no evidence to support the use of elastography in fecal incontinence evaluation.

Wide color gamut switchable autostereoscopic 3D display based on directional quantum-dot backlight

A switchable autostereoscopic 3-dimensional(3D) display device with wide color gamut is introduced in this paper. In conjunction with a novel directional quantum-dot(QD) backlight, the precise scanning control strategy, and the eye-tracking system, this spatial-sequential solution enables our autostereoscopic display to combine all the advantages of full resolution,wide color gamut, low crosstalk, and switchable 2D/3D. And also, we fabricated an autostereoscopic display prototype and demonstrated its performances effectively. The results indicate that our system can both break the limitation of viewing position and provide high-quality 3D images. We present two working modes in this system. In the spatial-sequential mode,the crosstalk is about 6%. In the time-multiplexed mode, the viewer should wear auxiliary and the crosstalk is about 1%,just next to that of a commercial 3D display(BENQ XL2707-B and View Sonic VX2268 WM). Additionally, our system is also completely compatible with active shutter glasses and its 3D resolution is same as its 2D resolution. Because of the excellent properties of the QD material, the color gamut can be widely extended to 77.98% according to the ITU-R recommendation BT.2020(Rec.2020).

TACC diagnosed by transoesophageal endoscopic ultrasonography:A case report

BACKGROUND Primary adenoid cystic carcinoma in the trachea(TACC)is a rare tumour.Tracheal bronchoscopy is always chosen as a routine approach to obtain a pathological diagnosis,but it can be associated with an increased risk of asphyxia.CASE SUMMARY We describe a case of TACC in a patient evaluated by chest computed tomography(CT)with three-dimensional reconstruction imaging and diagnosed by transoesophageal endoscopic ultrasonography.The pathological diagnosis confirmed tracheal adenoid cystic carcinoma.CONCLUSION We highlight the importance of CT and provide a successful exploration of transoesophageal biopsy as a safe alternative approach.