Localization of Ectopic Hyperparathyroidism: Ultrasound Versus 99mTc-sestamibi, 4-Dimensional Computed Tomography, and 11C-choline Positron Emission Tomography/Computed Tomography.

OBJECTIVE: To investigate the usefulness of ultrasound (US) for the localization of ectopic hyperparathyroidism and compare it with 99mTc-sestamibi (99mTc-MIBI), 4-dimensional computed tomography (4D-CT), and 11C-choline positron emission tomography/ computed tomography (PET/CT). METHODS: Of the 527 patients with surgically confirmed primary hyperparathyroidism, 79 patients with ectopic hyperparathyroidism were enrolled. The diagnostic performance of US, 99mTc-MIBI, US + MIBI, 4D-CT, and 11C-choline PET/CT was calculated, and the factors affecting the sensitivity of US and 99mTc-MIBI were analyzed. RESULTS: Eighty-three ectopic parathyroid lesions were found in 79 patients. The sensitivity was 75.9%, 81.7%, 95.1%, 83.3%, and 100% for US, 99mTc-MIBI, US + MIBI, 4D-CT, and 11C-choline PET/CT, respectively. The difference in sensitivity among these different modalities did not achieve statistical significance (P > .05). The US sensitivity was significantly higher for ectopic lesions in the neck region than for those in the anterior mediastinum/chest wall (85.9% vs. 42.1%, P < .001). The 99mTc-MIBI and 4D-CT sensitivity was not significantly different between these two groups (84.1% vs. 94.6%, P = .193 and 81.3% vs. 85.7%, P = 1). The 11C-choline PET/CT sensitivity was 100% in both groups. CONCLUSIONS: US is a valuable tool for the localization of ectopic hyperparathyroidism, especially for ectopic lesions in the neck region.

Sudden Sensorineural Hearing Loss after Pituitary Adenoma Resection-A Case Series with Literature Review.

Objective Complications after transsphenoidal surgery for pituitary adenoma have been well documented in the literatures, but the occurrence of delayed sudden sensorineural hearing loss (SNHL) after pituitary adenoma resection is extremely rare. In this study three cases who developed sudden SNHL 3 to 7 days after pituitary adenoma surgery without experiencing cerebrospinal fluid leak or meningitis were presented, and the possible causes of SNHL were discussed. Methods Three cases with sudden hearing loss after transsphenoidal surgery for pituitary adenoma were reviewed. The past medical history, onset of sudden hearing loss, accompanying symptoms such as headache, tinnitus, dizziness and aural fullness, and the post-operative MRI images, therapy, and hearing results were reported. Results Three cases developed profound sudden SNHL on the 3rd to 7th post-operative day, all accompanied by prior headache, tinnitus and dizziness. One patient developed episodic vertigo, ear fullness accompanying with fluctuating hearing loss in the first post-operative month. Two patients had past medical history of arteriosclerosis and coronary heart disease or cerebral infarction. Two of three demonstrated obstructive hydrocephalus on MRI on the first post-operative day. Under treatment with prednisone orally, dexamethasone intratympanic injection, neurotrophic and vasodilatation drugs for 3 to 8 months, hearing of all three improved partially. Obstructive hydrocephalus and ischemia might be responsible for the hearing loss. Conclusion Post-operative obstructive hydrocephalus and ischemia of labyrinthine arteries might lead to the delayed SNHL after transsphenoidal surgery for pituitary adenoma.

[Correlations of 18F-Fluorodeoxyglucose Positron Emission Tomography/Magnetic Resonance Imaging Parameters with the Pathological Differentiation of Head and Neck Squamous Cell Carcinoma and Their Diagnostic Efficiencies].

Objective To evaluate the correlation of the positron emission tomography/magnetic resonance imaging (PET/MR) parameters with the pathological differentiation of head and neck squamous cell carcinoma(HNSCC) and the diagnostic efficiencies of PET/MR parameters. Methods Patients with clinical suspicion of HNSCC were included and underwent PET/MR scan. HNSCC was pathologically confirmed in all these patients. The PET/MR examination included PET and MR sequences of diffusion-weighted imaging (DWI) and T2-and T1-weighted imaging. The multiple parameters of PET/MR included the mean values of apparent diffusion coefficient(ADCmean) and the maximum and mean values of standardized uptake value (SUVmax and SUVmean) were measured and estimated. The correlations of all the parameters and distribution between the different tumor differentiation groups were analyzed. Logistic regression was utilized to build the model as the PET/MR combined parameter for predicting the differentiation by multiple parameters of PET/MR. The receiver operating characteristic curve was calculated for each parameter and the combination. Results Totally 23 patients were included in this study:9 patients (9 males and 0 female) had well-differentiated tumor,with an average age of (61.0±6.8)years;14 cases had moderately-differentiated (n=10) or poorly-differentiated tumors (n=4),with an average age of (62.0±9.1) years. All the patients were males. There was statistical correlation between SUVmean and SUVmax (P<0.001);however,ADCmean showed no statistical correlation with SUVmax and with SUVmean (P=0.42,P=0.13). ADCmean and SUVmean showed significant difference between well-differentiated group and moderately-poorly-differentiated group (P=0.005,P=0.007). Compared with the individual parameters,the combination of PET/MR parameters with SUVmean and ADCmean had higher efficacy in predicting tumor differentiation,with an area under curve of 0.84. Conclusions The distributions of ADCmean,SUVmax and SUVmean differ among HNSCC with different pathological differentiation. Compared with the individual parameters,the combination of the PET/MR parameters has higher efficiency in predicting tumor differentiation.

A reassessment of cervical surface anatomy via CT scan in an adult population.

Surface landmarks in the neck are important for orientations of cervical glands, arteries, veins, nerves, and vertebrae. Recent research suggests some orientations are not correct. What are the cervical landmark orientations in the Chinese population? In this study, two essential cervical anatomy planes, the thyroid cartilage and C7 planes, were assessed in living adult Chinese subjects using computed tomography (CT), and the hyoid, carotid bifurcation, cricoid cartilage, thyroid arteries, and vertebral artery were simultaneously positioned. After excluding patients with distorting pathology, a total of 108 cervical CT scans were examined. The thyroid cartilage plane commonly passed through the C5 (in males) or C4 (in females) vertebral level. The carotid artery bifurcated most commonly at C3 (left) or C4 (right), more than 10 mm above the thyroid cartilage plane bilaterally in most cases. Orientation of the carotid bifurcation according to the body or greater horn of the hyoid was more accurate. The superior thyroid artery was found a finger-breadth below the thyroid cartilage plane, and the inferior thyroid artery in the C7 plane. The inferior border of the cricoid cartilage was most often at C7 (in males) or C6 (in females). The vertebral artery entered the C6 transverse foramen in more than 80% of scans. This reassessment of cervical surface anatomy using modern imaging tools in vivo provides both qualitative and quantitative information for surgeons in clinical practice. Clin. Anat. 30:330-335, 2017. © 2017 Wiley Periodicals, Inc.

Value of CT Density Measurements in Distinguishing Parathyroid Adenoma,Thyroid,and Lymph Node.

Objective To explore the value of multi-phase contrast-enhanced computed tomography in the differential diagnosis of parathyroid adenoma,lymph node,and thyroid. Methods The enhanced multi-slice CT (MSCT) results of 21 parathyroid adenoma patients were analyzed,and their postoperative pathological specimens were examined. During the MSCT,the plain CT scan was recorded,along with the density of thyroid adenoma,lymph nodes,and thyroid at 35 s and 65 s (D0,D35,D65) following the injection of contrast medium. Results During the D0 phase,there was significant difference in CT values between the parathyroid adenoma and thyroid parenchyma[(45?12) HU vs.(90?15)HU,P=0.007]. According to ROC curve,75 HU,with 95.2% sensitivity and specificity,was the critical value for distinguishing the density of parathyroid adenoma and that of thyroid parenchyma. At 35 s following the injection of contrast medium,there was significant difference in the enhancement degree between parathyroid adenoma and lymph node[(182?39) HU vs.(80?20)HU,P=0.004]. According to ROC curve,111 HU,with 95.2 % sensitivity and specificity,was the critical value for distinguishing the density of parathyroid adenoma and that of lymph node 35 s following the injection of contrast medium. At 35 s to 65 s following the injection of contrast medium,the parathyroid adenoma experienced a decline in density,which was dramatically different from parathyroid adenoma,however,lymph node experienced a rise in density. Conclusion Enhanced CT measurements at different time points enable the differentiation among parathyroid adenomas,lymph nodes,and thyroid.

[Three-dimensional Pseudo-continuous Arterial Spin Label Non-contrast Enhanced Perfusion Imaging of Head and Neck Tumors with High-field MR System].

OBJECTIVE: To evaluate the feasibility of three-dimensional pseudo-continuous arterial spin label (3D pCASL) non-contrast enhanced perfusion imaging applied to head and neck tumors in high-field MR and detect the effects of different postlabeling delay (PLD) time on image quality and the reliability of repeated measurements of tumor blood flow (BF) in different 3D pCASL groups. METHODS: In this prospective study,all the 25 patients received neck 3D pCASL non-contrast enhanced perfusion examinations in a 3.0 T MR system by using an 8-channel head and neck joint coil. Conventional T1-weighted (TIWI) and T2-weighted imaging (T2WI) were performed firstly. Finally,three 3D pCASL with different PLD time [ASL1(PLD1=1525 ms),ASL2 (PLD2=2025 ms), ASL3(PLD3=2525 ms)] were acquired. Patients' perfusion-weighted images acquired from different 3D pCASL sequences underwent the analysis of signal to noise ratio (SNR) and contrast noise ratio (CNR) for tumors. Two observers performed the qualitative assessments on spiral artifacts and vascular artifacts of perfusion-weighted images from different 3D pCASL sequences. Blood flow (BF) of tumors from different 3D pCASL sequences were measured by the two observers respectively for the first time and by observer 2 for the second time. RESULTS: Seventeen enrolled patients (age:50.1 ± 12.7 years,M/F=10:7) with histopathologic. RESULTS: underwent the evaluation of image quality and measurements of BF values. The SNRs and CNRs of ASL1,ASL2, and ASL3 showed a descending trendency. SNRs (P=0.011) and CNRs (P=0.009) of ASL1 were significant higher than those of ASL3. There was no significant difference of scores of spiral artifacts among the three ASL groups (P=0.932). The scores of vascular artifacts of ASL1,ASL2,and ASL3 showed a descending trendency,also. And scores of ASL1 was significant higher than that of ASL3(P=0.000). The intraclass correlation coefficient (ICC) of intre-and intraobserver were high (ICC>0.9). Although the BF values of ASL1,ASL2, and ASL3 showed an ascending trendency,there was no significant difference among the three groups (P=0.977). CONCLUSIONS: The 3D pCASL no-contrast enhanced perfusion MR imaging can be used for head and neck tumor. The image quality of perfusion weighted images and reliability of BF measurements were satisfied. The 3D pCASL series with PLD of 1525 ms and 2025 ms have better image quality than PLD of 2525 ms. And BF values do not show significant statistic difference among the three groups. Therefore, 3D pCASL series with PLD of 1525 ms and 2025 ms are more suitable for the perfusion imaging of head and neck tumors

Deep learning reconstruction improves the image quality of low-dose temporal bone CT with otitis media and mastoiditis patients.

Objective: To evaluate the image quality of low-dose temporal bone computed tomography (CT) in otitis media and mastoiditis patients by using deep learning reconstruction (DLR). Materials and methods: A total of ninety-seven temporal bones from 53 consecutive adult patients who had suspected otitis media and mastoiditis and underwent temporal bone CT were prospectively enrolled. All patients underwent high resolution CT protocol (group A) and an additional low-dose protocol (group B). In group A, high resolution data were reconstructed by filter back projection (FBP). In group B, low-dose data were reconstructed by DLR mild (B1), DLR standard (B2) and DLR strong (B3). The objective image quality was analyzed by measuring the CT value and image noise on the transverse image and calculating the signal-to-noise ratio (SNR) on incudomallear joint, retroauricular muscle, vestibule and subcutaneous fat. Subjective image quality was analyzed by using a five-point scale to evaluate nine anatomical structures of middle and inner ear. The number of temporal bone lesions which involved in five structures of middle ear were assessed in group A, B1, B2 and B3 images. Results: There were no significant differences in the CT values of the four reconstruction methods at four structures (all p > 0.05). The DLR group B1, B2 and B3 had significantly less image noise and a significantly higher SNR than group A at four structures (all p < 0.001). The group B1 had comparable subjective image quality as group A in nine structures (all p > 0.05), however, the group B3 had lower subjective image quality than group A in modiolus, spiral osseous lamina and stapes (all p < 0.001), the group B2 had lower subjective image quality than group A in modiolus and spiral osseous lamina (both p < 0.05). The number of temporal bone lesions which involved in five structures for group A, B1 and B2 images were no significant difference (all p > 0.05), however, the number of temporal bone lesions which involved in mastoid for group B3 images were significantly more than group A (p < 0.05). The radiation dose of high resolution CT protocol and low-dose protocol were 0.55 mSv and 0.11 mSv, respectively. Conclusion: Compared with high resolution CT protocol, in the low-dose protocol of temporal bone CT, DLR mild and standard could improve the objective image quality, maintain good subjective image quality and satisfy clinical diagnosis of otitis media and mastoiditis patients.

Normative measurements of extraocular musculature by multislice computed tomography.

Objective To establish the normal measurements of diameter of extraocular muscles (EOMs) by multislice computed tomography (CT). Methods Orbits of 50 volunteers (25 male and 25 female) were scanned with a multislice CT scanner. For each subject, one axial image at the central level of the eyeball, one coronal image about 1 cm behind globe, and two oblique sagittal images respectively along the left and right optic nerve were used for measurements of the thickness and width of EOMs. The statistic significance of measurement value between male and female and between left and right eyes was evaluated. Results There were no significant differences in the thickness and width of superior muscle group, lateral rectus, medial rectus, lateral rectus, superior oblique, inferior oblique and the thickness of levator palpebrae superioris between the left and right eyes as well as between male and female groups (all P>0.05). The thickness of superior muscle group and inferior rectus had not significant difference (2.9±0.7 vs. 3.3±0.8 mm, P=0.162), while the thickness of medial rectus was significantly higher than that of lateral rectus (3.1±0.5 vs. 2.2±0.6 mm, P=0.000). Conclusions The CT measurement of extraocular musculature is simple and time-saving and can be applied in the clinical work. The normative data obtained may be useful in determining pathologic enlargement of the EOMs in both thyroid-associated orbitopathy patients and other various orbital conditions.

Quantitative evaluation of extraocular muscle with high-field magnetic resonance in patients with Graves' ophthalmopathy with upper-lid retraction.

OBJECTIVE: To evaluate the feasibility of high-field magnetic resonance in measuring the thickness and width of extraocular muscles, calculate the ratio of thickness to width, and summarize the characters of the diameters and its ratio in patients with Graves' ophthalmopathy (GO) with upper-lid retraction. METHODS: Sixteen GO patients with upper-lid retraction (GO group) and 14 healthy control group were enrolled in this study. All the patients underwent enhanced high-field magnetic resonance orbital scan. The thickness and width of extraocular muscles were measured on axial, coronal or oblique sagittal enhanced T1 weighted images. The ratio of thickness to width (R1) and width to thickness (R2) were calculated. The diameters or ratio was evaluated as enlarged when they were 2 standard deviation greater than mean values of extraocular muscle in healthy control. RESULTS: The thickness of levator palpebrae superioris, medial rectus, and inferior rectus muscles in GO group were significantly larger than those in the control group (P=0.000, P=0.017, P=0.032, respectively. The width of superior oblique muscles in GO group was significantly larger than that in control group (P=0.000). The R1 values of levator palpebrae superioris, inferior rectus, medial rectus, and lateral rectus muscles in GO group were significant larger than those in the control group (P=0.000,P=0.037, P=0.019,P=0.032, respectively. The R2 value of superior oblique muscles was significant larger than that in the control group (P=0.027). Aslo in GO group, 32 extraocular muscles showed an increased thickness. 47% of thickened extraocular muscles had an increased R1. CONCLUSIONS: Enhanced orbit imaging with high-field magnetic resonance is helpful in the quantitative assessment of the thickness and width of extraocular muscles. In GO patients, in addition to the levator palpebrae superioris muscles, some other extraocular muscles also becomes thicker. Moreover, the increased diameters of superior oblique muscles is mainly due to the increase of its width R1 and R2 values can reflect the thickness and width of extraocular muscles and their relationship.

Triamcinolone acetonide injection in the treatment of upper eyelid retraction in Graves' ophthalmopathy evaluated by 3.0 Tesla magnetic resonance imaging.

Purpose: To evaluate changes in the levator palpebrae superioris (LPS) muscle on 3.0 T magnetic resonance imaging (MRI) after triamcinolone acetonide injection for treating upper lid retraction (ULR) with Graves' ophthalmopathy (GO) and to explore the value of LPS muscle quantitative measurement for clinical treatment. Methods: Patients with GO showing ULR were studied retrospectively and they underwent 3.0 T MRI scans before and after subconjunctival injection o f triamcinolone acetonide. The largest thickness (T) and highest signal intensity (SI) of LPS muscle on the affected eyes were measured in the sequences of coronal T2-weighted, fat-suppressed fast spin echo imaging (T2WI-fs) and T1-weighted, fat-suppressed, contrast-enhanced fast spin echo imaging (T1WI-fs + C), respectively. The SI ratio (SIR) (LPS muscle SI/ipsilateral temporalis SI) was calculated individually. Depending on the therapeutic effect, patients were divided into effective group and non-effective group. Independent t-test was used to compare SIR and T of LPS muscle in different treatment groups before treatment, and paired sample t-test was used to compare SIR and T of LPS muscle before and after treatment. Then cut-off level for predicting therapeutic effect and the receiver operating characteristic curve (ROC) curve were analyzed. Results: Sixty-two patients (77 eyes) were enrolled. After treatment, the T of LPS muscle showed significant decrease in all sequences in both effective and non-effective treatment groups. However, changes in SIR of LPS muscle in the two groups were different; SIR of LPS muscle on T2WI-fs and T1WI-fs + C decreased after treatment in the effective group (PT2 < 0.001, PT1 + C < 0.001) and SIR of LPS muscle showed no statistically difference in all sequences (all P > 0.05) in the non-effective group. There was a correlation between SIR of LPS muscle before treatment and after treatment with triamcinolone acetonide injection, which was that SIR of LPS muscle in the effective treatment group was lower than that in the non-effective treatment group on T1WI-fs + C (P < 0.001). SIR of LPS muscle on T1WI-fs + C showed 87.5% sensitivity and 66.7% specificity to predict therapeutic effect (area under the ROC curve [AUC] = 0.840). Conclusion: In GO patients with ULR, 3.0 T MRI can be used to evaluate the response of triamcinolone acetonide injection. SIR of LPS may be a predictor of its efficacy.

Effects of Danhong Injection () on Peri-Procedural Myocardial Injury and Microcirculatory Resistance in Patients with Unstable Angina Undergoing Elective Percutaneous Coronary Intervention: A Pilot Randomized Study.

OBJECTIVE: To evaluate the effect of Danhong Injection (, DH) on the index of microcirculatory resistance (IMR) and myocardial injury in patients with unstable angina undergoing elective percutaneous coronary intervention (PCI). METHODS: Seventy-eight patients with unstable angina were randomly divided into DH group (39 cases) and the control group (39 cases) during elective PCI. Randomization was performed using a random-number table. The DH group received DH at a dosage of 40 mL (mixed with 250 mL saline, covered by a light-proof bag, intravenous drip) during PCI and daily for 7 consecutive days, while the control group only received the same dosage of saline. Both groups received standardized treatment. The IMR and fractional flow reserve (FFR) were measured at maximal hyperemia before and after PCI. Myocardial markers, including myoglobin, creatine kinase (CK), creatine kinase MB (CK-MB), and coronary troponin T (cTnT) values were measured at baseline and 24 h after PCI. RESULTS: Among the 78 patients enrolled, the baseline and procedural characteristics were similar between the two groups. There was no significant difference in pre-PCI myocardial markers and coronary physiological indexes between the two groups. However, post-PCI CK and CK-MB levels in the DH group were significantly lower than those in the control group (111.97 ± 80.97 vs. 165.47 ± 102.99, P=0.013; 13.08 ± 6.90 vs. 19.75 ± 15.49, P=0.016). Post-PCI myoglobin and cTNT-positive tend to be lower in the DH group than in the control group but did not reach statistical significance (88.07 ± 52.36 vs. 108.13 ± 90.94, P=0.52; 2.56% vs.7.69%, P=0.065). Compared with the control group, the post-IMR levels of the DH group tended to decrease, but there was no statistical difference (20.73 ± 13.15 vs. 26.37 ± 12.31, P=0.05). There were no statistical differences in post-FFR in both groups. The peri-procedural myocardial injury of the DH group was significantly lower than that of the control group (2.56% vs. 15.38%, P=0.025). During the 30-d follow-up period, no major adverse cardiovascular events occurred in either group. CONCLUSION: This study demonstrated benefit of DH in reducing myocardial injury and potential preserving microvascular function in patients with unstable angina undergoing elective PCI.

Resveratrol inhibits MUC5AC expression by regulating SPDEF in lung cancer cells.

BACKGROUND: MUC5AC was recently identified to play important roles in the proliferation and metastasis of malignant mucinous lung tumor cells. Resveratrol (Res), a natural compound with anticancer effects in lung cancer cells, has been reported to inhibit mucin production in airway epithelial cells. This study aimed to investigate the inhibitory effect of Res on MUC5AC expression in lung mucinous adenocarcinoma cells and the potential mechanisms. METHODS: Mucus-producing A549 human lung carcinoma cells were used to test the effects of Res on SPDEF and MUC5AC expression. Gene and protein expression was assessed by real-time quantitative PCR (qPCR), immunofluorescence and western blotting assays. SPDEF lentivirus was used to upregulate SPDEF expression levels in mucus-producing A549 human lung carcinoma cells. Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay. RESULTS: Res decreased MUC5AC expression in an SPDEF-dependent manner in mucus-producing A549 human lung carcinoma cells, and this change was accompanied by decreased ERK expression and AKT pathway activation. Moreover, SPDEF was found to be overexpressed in lung adenocarcinoma (LUAD), especially in mucinous adenocarcinoma. In-vitro functional assays showed that overexpression of SPDEF reduced the chemosensitivity of A549 cells to cisplatin (DDP). In addition, Res treatment increased A549 cell chemosensitivity to DDP by inhibiting the SPDEF-MUC5AC axis. CONCLUSION: Our results indicate that the SPDEF-MUC5AC axis is associated with DDP sensitivity, and that Res decreases SPDEF and MUC5AC expression by inhibiting ERK and AKT signaling in A549 cells, which provides a potential pharmacotherapy for the prevention and therapeutic management of mucinous adenocarcinoma.

[Assessment of coronary stent lumen visibility and patency by dual-source computed tomographic angiography].

OBJECTIVE: To assess the in-stent lumen visibility and image quality of coronary stents by dual-source computed tomography (DSCT) coronary angiography, and the diagnostic accuracy of DSCT in the detection of coronary in-stent restenosis. METHODS: DSCT was performed at 147 stents in 78 patients at an interval of (21.8?22.2) months after coronary stent implantation. Axial multi-planar reconstruction of the stents and curved-planar reconstruction through the median of the stents were evaluated for stent image quality on a 5-point scale, and the stent lumen diameters were detected. Thirty out of these 78 patients underwent conventional coronary angiography within one month after CT angiography. The patency of 60 stents were independently evaluated by two blinded readers. RESULTS: Image quality was good to excellent on average score (1.6?0.6) . Stent image quality score was correlated with stent diameter, stent location, and heart rate. All stents were assessable in lumen visibility with an average visible lumen diameter percentage of (72.2?12.2) %. Visible lumen diameter percentage was correlated with stent diameter and stent location. For the stents with calcified plaques, the visible lumen diameter percentage at the calcified site was significantly lower than that at the non-calcified site (P<0.001) . Compared with the conventional coronary angiography, 12 out of 14 in-stent stenoses were correctly detected. The sensitivity, specificity, positive predictive value, and negative predictive value for the detection of in-stent stenosis was 85.7%, 95.7%, 85.7%, and 95.7%, respectively. For stents whose diameter >0.275cm, the sensitivity, specificity, positive predictive value, and negative predictive value were all 100%. The agreement between CT findings and coronary angiography results was 93.3%, and it was correlated with stent diameter and heart rate. CONCLUSIONS: Using a DSCT, coronary stent lumen is partially visible and the image quality is high. Stent diameter and location can influence the stent lumen visibility and image quality. DSCT has a high diagnostic accuracy for the detection of in-stent restenosis and may be a valuable modality for the follow-up of coronary artery stent patency."

[Coronary computed tomographic angiography using low-dose prospectively electrocardiographic triggered high-pitch spiral acquisition by dual-source computed tomography: image quality and radiation dose].

OBJECTIVE: To evaluate image quality (IQ) and radiation exposure of coronary computed tomographic angiography (CTA) with prospectively electrocardiographic (ECG) triggered high-pitch spiral acquisition using dual source CT. METHODS: Totally 75 consecutive patients with a stable heart rate (HR) ≤65 bpm underwent coronary CTA. patients were divided into two groups according to their HR (group A HR≤60 bpm, group B HR >60 bpm to≤65 bpm) . A dual-source CT scanner was used (0.6mm collimation, 0.28s rotation time, 80~100 kV, 370 mAs/rot) . Data acquisition was prospectively ECG-triggered at 60% of the R-R interval with a pitch of 3.4. Images were reconstructed with 75ms temporal resolution, 0.75mm slice thickness and 0.5mm increment. IQ was evaluated using a four-point scale (1=excellent, 4=unevaluable) . RESULTS: The mean HR and scan time of all patients was (57.2 ± 4.8) bpm and (0.42 ± 0.02) s. Of 1103 coronary artery segments, 934 (84.7%) had an IQ score of 1, 135 (12.2%) score of 2, 18 (1.6%) score of 3,and 16 (1.5%) were rated as unevaluable. There was no significant difference between the two groups in IQ [mean score (1.19 ± 0.52 vs. 1.22 ± 0.55;Z=-1.107,P=0.268) . The rate of evaluable segments showed no significant difference between the two groups (98.5% vs. 98.6%;X2=0.000,P=1.000) . Mean dose-length product of all patients was (67.2 ± 30.4) mGy × cm, mean effective dose was (0.94 ± 0.43) mSv. CONCLUSION: In patients with a stable HR of 65 bpm or less, prospectively ECG-triggered high-pitch spiral CT acquisition provides high IQ at low radiation dose.

Validation and Precision of Mixed Reality Technology in Baha Attract Implant Surgery.

OBJECTIVE: To test the feasibility of image-guided Baha Attract implant surgery with mixed reality (MR) in the form of the HoloLens to visualize critical structures and facilitate precise Baha implant placement. METHODS: A cadaveric case study of bilateral Baha Attract implant approaches was conducted using Star Atlas MR three-dimensional (3D) medical interaction system guidance at the Otolaryngology Department of PUMCH, Beijing, China. The accuracy of visual surface registration was determined by the target registration error (TRE) between the predefined points on the preoperative 3D holographic Baha Attract implant model and the postoperatively reconstructed 3D model. RESULTS: Bilateral Baha Attract implantation was completed successfully for all four cadaveric heads using the Star Atlas MR 3D medical interaction system with the HoloLens. The preoperative 3D digital model characteristics (including bone quality and thickness and avoidance of cranial vessels, air cells, and cranial sutures) corresponded well with the 3D model of the actual implantation reconstructed postoperatively. The median TRE of our system was 2.97 mm (ranging from 1.98 to 4.58 mm) in terms of distance and 2.76 degrees (ranging from 0.59 to 6.4 degrees) in terms of angle. CONCLUSIONS: Applying MR technology in the form of the HoloLens in Baha Attract implant surgery is feasible and could improve the accuracy of the surgery. The described MR system for Baha Attract implantation has the potential to improve the surgeon's confidence, as well as the surgical safety, efficiency, and precision.

Pulmonary manifestations of Sjögren's syndrome.

BACKGROUND: Primary Sjögren's syndrome (PSS) is associated with various histological patterns of interstitial lung disease. Although chest images and lung function studies showed that lung involvement predominantly occurs in small airways, pathological findings were not consistent with the results of high-resolution CT (HRCT) and lung function tests. OBJECTIVES: To investigate the pathological characteristics of PSS-associated interstitial lung disease (PSS-ILD) and their relationship with HRCT lung function tests. METHODS: Fourteen patients diagnosed as PSS who underwent surgical lung biopsy in Peking Union Medical College Hospital from October 2000 to October 2006 were reviewed. Histopathologic findings, radiologic findings and lung function tests were analyzed. RESULTS: The study included 13 women. The median age was 46 years. Most patients presented with dyspnea and cough. CT scans revealed bilateral ground-glass, consolidative, reticular and nodular opacities and cyst lesions. The histological patterns included nonspecific interstitial pneumonia (NSIP) cellular pattern associated with organizing pneumonia (OP), NSIP mixed pattern associated with OP, noncaseating granulomas, chronic bronchiolitis, follicular bronchiolitis, constrictive bronchiolitis, lymphocytic interstitial pneumonia associated with follicular bronchiolitis, NSIP mixed pattern associated with follicular bronchiolitis, NSIP mixed pattern coexisting with chronic bronchiolitis, OP associated with chronic bronchiolitis, and noncaseating granulomas coexisting with OP. Treatment included prednisone and cyclophosphamide. During the follow-up period (median 38 months), most patients improved or remained stable. The patient with constrictive bronchiolitis died from progression of primary disease. CONCLUSIONS: The histopathologic patterns of PSS-ILD included lung interstitial involvement and small airway involvement or both. Corticosteroid therapy combined with cyclophosphamide was administered with a favorable response in the majority of patients.

Assessment of coronary stents by 64-slice computed tomography: in-stent lumen visibility and patency.

OBJECTIVE: To assess lumen visibility of coronary stents by 64-slice computed tomography (CT) coronary angiography, and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation. METHODS: Totally, 60 patients (54 males, aged 57.0+/-12.7 years) and 105 stents were investigated by 64-slice CT at a mean interval of 20.0+/-16.6 months after coronary stents implantation. Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale (1=excellent, 5=non-assessable), and stent lumen diameter was detected. Conventional coronary angiography was performed in 18 patients, and 32 stents were evaluated. RESULTS: Image quality was good to excellent on average (score 1.71+/-0.76). Stent image quality score was correlated to heart rate (r=0.281, P<0.01) and stent diameter (r=-0.480, P<0.001). All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7%+/-13.6%. Visible lumen diameter percentage was correlated to heart rate (r=-0.193, P<0.05), stent diameter (r=0.403, P<0.001), and stent image quality score (r=-0.500, P<0.001). Visible lumen diameter percentage also varied depending on the stent type. In comparison with the conventional coronary angiography, 4 of 6 in-stent stenoses were correctly detected. The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6%, respectively. CONCLUSIONS: Using a 64-slice CT, the stent lumen is partly visible in most of the stents. And 64-slice CT may be useful in the assessment of stent patency.

[Comparison of imaging characteristics of magnetic resonance myocardial delayed enhancement between ischemic and nonischemic myocardial diseases].

OBJECTIVE: To compare the imaging characteristics of magnetic resonance (MR) delayed enhancement between ischemic and nonischemic myocardial diseases. METHODS: We retrospectively analyzed the imaging and clinical characteristics of 25 patients who had MR delayed enhancement. RESULTS: Among the 25 cases, 19 cases were ischemic heart diseases, in which the delayed enhancement was subendocardium, non-transmural or transmural; two cases were hypertrophic cardiomyopathy, in which the delayed enhancement was midwall in the hypertrophic myocardium, strip- and patch-shaped; one case was dilated cardiomyopathy, in which the delayed enhancement was diffuse small midwall spots two cases was restrictive cardiomyopathy, in which the delayed enhancement was located in the area of the subendocardium both of the right and left ventricles; and one case was a mass of the lateral wall of the left ventricle, in which the delayed enhancement with a clumpy shape was shown. CONCLUSIONS: MR myocardial delayed enhancement is not a specific sign of myocardial infarction of ischeminc heart disease. The differentiation of the etiology of the delayed enhancement relies upon both the MR images and the clinical history.

[Evaluation of cardiac structure and function by cardiac magnetic resonance imaging in healthy volunteers].

OBJECTIVE: To evaluate the role of cardiac magnetic resonance (CMR) sequence in assessing the cardiac structure and function. METHODS: A total of 36 healthy volunteers were examined with fast imaging employing steady-state acquisition cine MR sequence. All the MR images were processed on Report Card software to test the cardiac dimensions and function. The relationships between the CMR results and the ultrasonic cardiography (UCG) results were analyzed. RESULTS: CMR analysis showed that interventricular septum thickness, left ventricle posterior wall thickness, end diastolic dimension of left ventricle, and end systolic dimension of left ventricle were (9.2 +/- 2.1), (8.0 +/- 2.1), (48.6 +/- 5.5), and (30.3 +/- 5.3) mm, respectively. Major dimension of right ventricle, minor dimension of right ventricle, index of major, dimension of right ventricle and index of minor dimension of right ventricle were (69.2 +/- 9.7), (30.6 +/- 6.6) mm, and (39.4 +/- 5.5), (18.1 +/- 3.4) min/m2, respectively. The left ventricle indicators above measured by CMR correlated with those by UCG (r = 0.843, 0.784, 0.686, 0.730, all P < 0.01). CMR analysis showed that left ventricular end diastolic volume, right ventricular end diastolic volume, left ventricular end systolic volume, and right ventricular end systolic volume were (93.6 +/- 17.2), (108.6 +/- 28.2), (39.5 +/- 13.0), and (45.6 +/- 15.1) ml, respectively. The left ventricular ejection fraction and right ventricular ejection fraction were (58.5 +/- 8.19)% and (58.2 +/- 7.4)% , respectively. Left ventricular ejection fraction measured by CMR was correlated with that (64.1 +/- 6.8)% by UCG (r = 0.75, P < 0.01). CONCLUSIONS: CMR sequence with standard location is well applicable for accurate measurement of left and right ventricle dimensions and function, especially for right ventricle. CMR can be used to diagnose the heart disease and monitor the efficacy.

[Diagnostic value of dual-source CT coronary angiography on the detection of coronary artery disease with myocardial perfusion defect].

OBJECTIVE: To determine the accuracy of dual-source CT (DSCT) coronary angiography (CAG) for the diagnosis of coronary artery disease (CAD) that induces perfusion defects at myocardial perfusion imaging (MPI) with single photon emission computed tomography (SPECT), by using SPECT and conventional CAG as the reference standard. METHODS: Thirty-five patients with suspected or known CAD underwent both DSCT coronary angiography and MPI (using exercise or adenosine stress-rest protocol) with technetium-99m sestamibi SPECT. All the patients were beta-blockers-naïve before DSCT scan. The DSCT CAG studies were classified as having no stenosis, non-obstructive (< 50% luminal narrowing) stenosis, or obstructive (> or = 50% luminal narrowing) stenosis. MPI examinations were classified as showing normal or abnormal (reversible and/or fixed defects). A comparative regional analysis of coronary stenosis on DSCT versus myocardial perfusion on SPECT was made. In a subset of 20 patients, CAG was performed as a reference standard for CT angiography. RESULTS: On the basis of the DSCT data, 98.4% of coronary segments were assessable. Twenty-seven branches were classified as having no stenosis, among which 85% had normal MPI. Nine branches showed non-obstructive stenosis and 69 branches showed at least one obstructive lesion. Only 50 (64%) branches with an abnormal DSCT had abnormal MPI; even in branches with obstructive stenosis on DSCT, 23 (33%) still had a normal MPI. By receiver operating characteristic curve analysis, at the optimal cutoff value of 58% stenosis, the sensitivity and specificity of DSCT to detect myocardial perfusion defect as defined by SPECT were 85% and 65%. In the subgroup compared with CAG, the sensitivity and specificity of DSCT to identify obstructive stenosis were 93% and 96%. CONCLUSIONS: DSCT and SPECT provide mutually complementary information on CAD. CT angiography can help rule out functionally relevant CAD, but has poor capability in predicting ischemia. DSCT provides high-quality diagnostic image without heartbeat controlling and has a high accuracy in detecting obstructive stenosis.