[The value of dynamic contrast-enhanced MRI in the differentiation between benign and malignant lacrimal epithelial tumors].

Objective: To investigate the diagnostic performance of multiparametric dynamic contrast-enhanced MRI(DCE-MRI) for the differentiation between benign and malignant larcrimal gland epithelial tumors. Methods: The clinical and imaging data of 104 patients with epithelial tumors of the lacrimal gland who underwent orbital MRI scan and met the inclusion criteria in Beijing Tongren Hospital from January 2011 to December 2017 were retrospectively collected, including 48 males and 56 females, aged from 12 to 77 (43±7) years. Sixty-three cases of benign epithelial tumors and 41 cases of malignant epithelial tumors were examined by DCE-MRI. The parameters of semiquantitative analysis including: time to peak enhancement (Tpeak), maximum enhancement ratio (ERmax), Slope, washout ratio (WR) and time-signal intensity curve (TIC) types. The parameters of quantitative analysis including: volume transfer constant (Ktrans), the extravascular extracellular volume fraction (Ve) and rate constant (Kep). Receiver operating characteristic (ROC) curve analysis was performed for DCE-MRI parameters with statistically significant differences, the area under the curve (AUC) was calculated, the diagnostic threshold was determined, and the diagnostic performance was evaluated. Logistic regression analysis was used to determine the best parameters for differential diagnosis of benign and malignant epithelial tumors of the lacrimal gland. Results: For the semiquantitative analysis of DCE-MRI, malignant lacrimal gland epithelial tumor had a significantly shorter Tpeak than benign masses [(103.77±57.87) s vs (187.80±77.01) s,P<0.001)], while had a higher value in ERmax, Slope [M(Q1,Q3)] and WR in malignant masses compared with benign one [1.55±0.39 vs 1.36±0.33; 1.76 (0.97,2.27) vs 0.62 (0.50,0.93); 7.70%(1.40%, 21.60%)% vs 0(0, 0),all P<0.05)].The TICs of benign lacrimal tumors mainly showed a persistent type (49/63),while most malignant lacrimal tumors mainly showed a plateau type (25/41). For the quantitative analysis of DCE-MRI, the values of Ktrans and Kep[M(Q1,Q3)] in malignant tumors were significantly greater than those of benign tumors (0.99±0.52/min vs 0.43±0.23/min, P<0.001; 1.33(0.83, 1.55)/min vs 0.55(0.46, 0.68)/min, P<0.001). No significant difference in Ve was found between the groups (0.76±0.20 vs 0.73±0.22,P=0.467). Through the statistical analysis, TIC types (OR=3.887,95%CI: 1.409-10.725) and Ktrans(OR=50.979,95%CI: 6.046-429.830) can provide superior diagnostic performance for predicting malignant lacrimal gland epithelial tumors, with a sensitivity of 78.05%, specificity of 77.78%,and sensitivity of 70.73%, specificity of 95.24%, respevtively. Furthermore, the comprehensive diagnostic performance of Ktrans in AUC was proven to be significantly better than that of TIC [0.875 (0.796-0.932) vs 0.798 (0.708-0.870),P=0.049]. Conclusions: Multiparametric DCE-MRI is helpful for the differential diagnosis of benign and malignant epithelial tumors of lacrimal gland. TIC type and Ktrans have higher diagnostic value, and the diagnostic performance of Ktrans is better than that of TIC.

[Analysis of the cognitive effects of monocular blindness and related influencing factors].

Objective: To investigate the cognitive effects of monocular blindness and related influencing factors. Methods: A cross-sectional study was conducted. The patients with monocular blindness (the age of onset <16 years) were enrolled from Beijing Tongren Eye Center, Beijing Tongren Hospital between January 2018 and June 2020. The Montreal cognitive assessment (MoCA) scale was applied to assess seven cognitive domains including visuospatial and executive function, naming, attention, etc. Based on MoCA scores, all the patients were classified into two groups: normal cognitive functions and cognitive impairment. Spearman's correlation was used to perform the single factor analysis of the influencing factors of cognitive functions. Multivariate linear regression analyses were applied to identify the independent influencing risk factors. Results: A total of 45 patients with monocular blindness were enrolled. There were 25 males and 20 females, with age at testing being (27±10) years.The incidence of cognitive impairment in 45 patients was 60.0% (27/45). The abnormal items ranking from a high to low rate were language (95.6%, 43 cases), delayed recall (75.6%, 34 cases), visuospatial and executive function (60.0%, 27 cases), abstract (44.4%, 20 cases), attention (35.6%, 16 cases), naming (20.0%, 9 cases), and orientation (0%). There were statistically significant differences (all P<0.05) in total score (21.9±3.3 vs. 27.4±1.4), visuospatial and executive function (3.2±1.7 vs. 4.6±0.7), naming (2.7±0.6 vs. 2.9±0.2), attention (5.3±1.0 vs. 5.8±0.4), language (1.1±0.8 vs. 1.8±0.8), abstract (1.1±0.8 vs. 1.8±0.5) and delayed recall (2.3±1.3 vs. 4.4±0.8) between two groups of patients with and without cognitive impairment. Spearman's correlation analysis showed visuospatial and executive functions, attention, abstract and MoCA total score were positively correlated with education years (correlation coefficients being 0.355, 0.424, 0.434 and 0.370, respectively; all P<0.05). Multiple linear regression showed that duration of blindness was correlated with naming (ß=-0.325), and years of education correlated with attention (ß=0.472), abstract ability (ß=0.441) and MoCA total score (ß=0.390) (all P<0.05). Conclusions: Monocular blindness may affect language, delayed memory and visuospatial executive functions. The duration of blindness is an independent risk factor, and higher education is a protective factor of the cognitive impairment.

[The value of ultrasonic elastography in the differential diagnosis of choroidal melanoma and choroidal hemangioma].

Objective: To explore the role of the scoring and strain ratio methods of ultrasonic elastography in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Methods: A cross-sectional study. Twenty-five patients (25 eyes) with choroidal melanoma treated in the Department of Ophthalmology, Beijing Tongren Hospital, Capital Medical University from July to October 2016 were included in this study. There were 13 males and 12 females, with an average age of (48±12) years old. Twenty-five patients (25 eyes) with choroidal hemangioma treated in the same period were selected for differential diagnosis, including 12 males and 13 females, with an average age of (37±13) years. The lesions were examined by ultrasound elastography and scored, and the strain ratio of the tumor to the orbital tissue was measured. Two independent sample t test was used to compare the difference in the elasticity score and strain ratio between choroidal melanoma and choroidal hemangioma. The sensitivity, specificity and area under the receiver operating characteristic (ROC) curve were calculated to analyze the value of the two methods in the differential diagnosis of choroidal melanoma and choroidal hemangioma. Results: The elastography score of choroidal melanoma was (3.48±0.77) points, including 2 points in 3 cases, 3 points in 8 cases, 4 points in 13 cases, and 5 points in 1 case. The elastography score of hemangioma was (2.28±0.46) points, including 2 points in 18 cases and 3 points in 7 cases. The difference in the elasticity score between patients with the two kinds of tumors was statistically significant (t=6.694, P<0.01). The strain ratio was 42.97±15.83 and 12.21±9.24 in the patients with choroidal melanoma and choroidal hemangioma, respectively, and the difference was statistically significant (t=8.392, P<0.01). Using 3 points as the diagnostic critical point of the elastography score, the sensitivity was 88.0%, the specificity was 72.0%, and the area under the ROC curve was 0.80 (95% cofidence interval: 0.663 to 0.900, P<0.01). Using 21.67 as the diagnostic critical point of the strain ratio, the sensitivity was 92.0%, the specificity was 92.0%, and the area under the ROC curve was 0.92 (95% cofidence interval: 0.808 to 0.978, P<0.01). Conclusions: Ultrasound elastography plays a role in the differential diagnosis of choroidal melanoma and choroidal hemangioma. The differential diagnostic value of the strain ratio method is higher than the scoring method. (Chin J Ophthalmol, 2020, 56: 676-680).

Upper airway morphological changes in obstructive sleep apnoea: effect of age on pharyngeal anatomy.

OBJECTIVE: To evaluate the upper airway morphology changes associated with ageing in adult Chinese patients with obstructive sleep apnoea. METHODS: A total of 124 male patients diagnosed with obstructive sleep apnoea by overnight polysomnography, who underwent upper airway computed tomography, were enrolled. The linear dimensions, cross-sectional area and volume of the upper airway region and the surrounding bony frame were measured. The association between ageing and upper airway morphology was analysed. RESULTS: Soft palate length, minimum cross-sectional area of the retroglossal region, lateral dimensions at the minimum cross-sectional area of the retropalatal and retroglossal regions, nasopharyngeal volume, and average cross-sectional area of the nasopharyngeal region were found to significantly increase with ageing in all patients, while the upper airway shape flattened with ageing. The volume of the retropalatal region increased with ageing among the patients with a body mass index of less than 24 kg/m2. The volume of parapharyngeal fat pad increased with ageing among patients with a body mass index greater than 28 kg/m2. CONCLUSION: A number of dimensional, cross-sectional and volumetric parameters of the pharynx increased with age, indicating that non-anatomical factors may play a more important role in the pathogenesis of obstructive sleep apnoea in aged patients.

[Value of CT in the differential diagnosis of Pseudomonas aeruginosa sinusitis and fungal ball in paranasal sinus caused by Aspergilus flavus].

Objective: To evaluate the value of CT in the differential diagnosis of Pseudomonas aeruginosa sinusitis and fungal ball in paranasal sinus caused by Aspergilus flavus. Methods: In this retrospective study, CT results of 74 cases of Pseudomonas aeruginosa sinusitis including 31 male cases and 43 female cases with age onset from 15 to 74 years old (mean±SD was 50±13) and 72 cases of fungal ball in paranasal sinus caused by Aspergilus flavus including 28 male cases and 44 female cases with age onset from 25 to 78 years old (mean±SD was 53±15) at Beijing Tongren Hospital confirmed by histopathology were enrolled from January 2013 to May 2017. The CT characteristics of the two groups of cases were compared using χ(2) test, and P<0.05 was considered statistically significant. Results: Soft tissue opacification of the involved paranasal sinus was found on CT in each case of the two groups. There were significant differences in the rate of single sinus involvement (44.6% and 90.3% respectively), the incidence of lesion associated with maxillary sinus (91.9% and 70.8% respectively), ethmoid sinus (41.9% and 2.8% respectively), frontal sinus (29.7% and 0 respectively), calcification (50.0% and 72.2% respectively), and the enlargement of maxillary sinus opening (13.2% and 35.3% respectively), in addition to the central calcification (83.8% and 59.6% respectively) between the two groups (all P<0.05). However, the incidence of sphenoid sinus involvement (32.4% and 34.7% respectively), bone sclerosis (56.8% and 62.5% respectively) or destruction(18.9% and 16.7% respectively) were not found different between the two groups (P>0.05). Conclusion: Though the CT findings are similar between the two diseases such as soft tissue opacification of the involved paranasal sinus with calcification and bone sclerosis or destruction, there are still a few characteristics on CT in differentiating the one from the other. The involvement of multi-sinuses, maxillary sinus, ethmoid sinus and frontal sinus, the central calcification are more common in the Pseudomonas aeruginosa sinusitis. However, the CT features including single sinus involvement, calcification and enlargement of maxillary sinus opening, can be seen more often in the fungal ball in paranasal sinus caused by Aspergilus flavus.

[Comparison of biometry with the Pentacam AXL, IOLMaster 700 and IOLMaster 500 in cataract patients].

Objective: To compare biometry with new biometers of Pentacam AXL and IOLMaster 700 and the widely used biometer of IOLMaster 500 in cataract patients. Methods: Cross-sectional study. A total of 223 eyes of 147 cataract patients from Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University during 4-8 December 2017 were recruited. There were 67 males and 80 females with an age of (64±11) years.The axial length (AL), mean keratometry (Km), anterior chamber depth (ACD) and white-to-white corneal diameter (WTW) from each device were recorded. The difference and agreement between the measurements were evaluated by ANOVA, LSD test, intraclass correlation coefficient and Bland-Altman analysis. Results: The success rate of AL measurement was 85.2% (190/223) with the Pentacam AXL, 96.9% (216/223) with the IOLMaster 700 and 90.6% (202/223) with the IOLMaster 500. There was no difference among devices in measuring the AL, Km and ACD (all P>0.05). Significant difference was found in WTW [(11.36±0.42) vs. (11.69±0.45) vs. (11.45±0.42) mm; F=34.696, P=0.000]. Intraclass correlation coefficient was 0.859-1.000, and Bland-Altman analysis showed good agreement among three devices. Conclusions: The new biometers of Pentacam AXL and IOLMaster 700 and the widely used IOLMaster 500 show no difference in measuring AL, Km and ACD. All three devices show good agreement in biometry of cataract patients. (Chin J Ophthalmol, 2019, 55: 515-521).

[The effect of genioglossus activity to velopharyngeal surgery in patient with obstructive sleep apnea hypopnea syndrome].

Objective: To investigate the effect of genioglossus (GG) activation at sleep onset on the outcome of velopharyngeal surgery in obstructive sleep apnea hypopnea syndrome (OSAHS) patients. Methods: Thirty-five patients between April 2014 and February 2015 in Beijing Tongren Hospital with OSAHS underwent overnight polysomnography with synchronous genioglossus electromyography (GGEMG) using intraoral electrodes. The upper airway (UA) anatomy was evaluated by three-dimensional computer tomography (3D-CT) in OSAHS patients. Then, all of the patients received velopharyngeal surgery, including revised uvulopalatopharyngoplasty (UPPP) with uvula preservation or UPPP combined transpalatal advancement pharyngoplasty. All patients were followed-up using polysomnography 3-6 months after surgery. T-test or Wilcoxon test were used to compare the variables between groups, and Spearman correlation analysis was used to test the correlation between parameters. Results: Thirty-five patients received velopharyngeal surgery. Twenty-two patients (62.86%) were responders, and 13 patients (37.14%) were non-responders. Responders had a higher mean GGEMG during sleep onset (15.31±3.74 vs. 9.92±2.93, t=4.504, P=0.001). The decreased AHI was significantly positively related to the sleep onset mean GGEMG (r=0.541, P=0.004) and the change in GGEMG (r=0.422, P=0.028). The decreased AHI was significantly negatively related to the minimal cross sectional airway area (mCSA,ρ=0.629,P=0.000) and the minimal lateral airway dimension (mLAT, ρ=0.484, P=0.009) at velopharynx. Conclusions: The outcome of velopharyngeal surgery was affected by the mean GGEMG during sleep onset. We speculated that the patient with higher GGEMG at sleep onset and narrower velopharynx were more suitable candidates for velopharyngeal surgery.

[Quantitative dynamic contrast enhancement MR imaging parameters in the prediction and evaluation of the treatment response of malignant sinonasal tumors to chemotherapy:a preliminary result].

Objective: To investigate the value of quantitative dynamic contrast enhancement MR imaging (DCE-MRI) parameters in the prediction and evaluation of the response to neoadjuvant chemotherapy in patients with malignant sinonasal tumors by comparing the parameter values before and after chemotherapy. Methods: DCE-MRI was performed in 14 patients (6 male cases, 8 female cases, 16-83 years) with malignant sinonasal tumors before chemotherapy in Beijing Tongren Hospital from January 2012 to December 2013 in which DCE-MRI was performed in 8 patients on the 7th, 21st and 42nd days after chemotherapy. The values of quantitative parameter including K(trans), K(ep), and V(e) of the tumor were assessed and the change rate of these quantitative parameter values after chemotherapy was calculated. Results: Response to chemotherapy of the tumor was found in 11 patients with malignant sinonasal tumors,whereas no response to chemotherapy of the tumor was confirmed in 3 patients. K(trans) ((0.75±0.28)/min) and K(ep) ((3.23±1.48)/min) values of the tumor before chemotherapy in patients with response to chemotherapy were significantly bigger than those ((0.43±0.41)/min, (1.34±0.42)/min) in patients with no response to chemotherapy (all P<0.01).There was no significant difference in V(e) values between two groups (P=0.165). Compared with K(trans) values of the tumor before chemotherapy,the change rate of K(trans) values decreased more than 40% on the 7th,21st and 42nd days after chemotherapy in the patients with treatment response,whereas the change rate did not decrease significantly in the patients without treatment response. Conclusion: The bigger K(trans) and K(ep) values of the tumor before chemotherapy,the better the treatment response of the tumor to chemotherapy.

[Application of MRI in the etiological diagnosis of special forms of strabismus].

Objective: To explore the imaging features of patients with special forms of strabismus and summarize the subtypes by using MRI imaging techniques. Methods: A retrospective case series study. Among the patients who visited the Beijing Tongren Hospital between 2006 and 2016, 1 113 patients were identified with special forms of strabismus after complete ophthalmic and orthoptic evaluations. These patients were further evaluated using several types of high-resolution MRI techniques of the oculomotor nerves in the brain, the cavernous sinus, and the orbits. Results: Among the 1 113 patients, 818 patients (73.5%) were identified with MRI abnormal conditions, and 295 patients (26.5%) were identified with MRI normal conditions. Nine different disease types were identified in the studied populations, which included 257 patients (23.1%) with congenital cranial dysinnervation disorders, 209 patients (18.8%) with thyroid associated ophthalmopathy, and 169 patients (15.2%) with abnormalities of the extraocular muscles. Other diseases included orbital fractures (3.3%, 37 patients), intraorbital inflammations (2.7%, 30 patients), tumors (2.3%, 26 patients), injuries of medial rectus muscle after endoscopic sinus surgery (1.2%,13 patients), and lesions of cavernous sinus (2.0%, 22 patients). Additional 55 patients (4.9%) were identified with other causes such as high myopia fixed esotropia, and so on. Conclusion: Summarizing the common clinical characteristics and rules with the help of MRI can further clarify the etiology of special forms of strabismus, and accurately guide the diagnosis and treatment of strabismus. (Chin J Ophthalmol, 2019, 55: 361-368).

[Magnetic resonance imaging study of endolymphatic hydrops based on 3D-FLAIR sequence after single-dose intravenous gadolinium injection].

Objective: To investigate the visualization of endolymph in patients with otogenic vertigo by intravenous administration of single dose of gadolinium contrast agents and magnetic resonance three-dimensional fluid-attenuated inversion recovery sequence (3D-FLAIR MRI), and further assess the extent of endolymphatic hydrops. Methods: From Beijing Tongren Hospital of Capital Medical University between October 2017 and June 2018, 30 patients (16 males, 14 females) with unilateral otogenic vertigo were involved in this study, with the age of 30 to 68 years, mean age of (53±10) years. Eight hours after intravenous administration of single dose (0.1 mmol/kg, body weight) of gadopentetate (Gd-DTPA), 3D-FLAIR sequence was performed in 30 patients. The location of endolymphatic hydrops was observed and then the degree of hydrops was quantitatively elevated by two radiologists. The consistency test was used to analyze the location and degree of endolymphatic hydrops in the two radiologists and the paired t-test was used to compare the difference between the affected and healthy side of endolymphatic spaces of the patients with otogenic vertigo. Results: In 30 patients, the gadolinium distributed in all parts of the perilymph inside the inner ear, and can accurately outline the boundaries of the peri-and endolymph. Twenty-six patients (26/30, 86.7%) were found to have unilateral endolymphatic hydrops, including 18 mild hydrops, 8 significant hydrops. The two radiologists had a very good agreement on the assessment of endolymphatic hydrops(kappa=0.864, ICC=0.959). In the 3D-FLAIR MR images of 26 patients with endolymphatic hydrops, the saccule (26/26, 100%) had a higher rate of hydrops than the cochlea and utricle(16/26, 61.5%; 14/26, 53.8%), and two radiologists had a very good agreement on the location of endolymphatic hydrops(kappa=0.820). Moreover, there was a significantly statistical difference between the affected and healthy area of the endolymphatic space in this study (P<0.01). Conclusion: The technique of 3D-FLAIR MR imaging through single dose intravenous gadolinium injection is feasible, which can estimate endolymphatic hydrops in patients with otogenic vertigo, and accurately classify the degree of hydrops.

[Value of the apparent diffusion coefficient in diffusion weighted imaging at 3.0T MR for differentiating lacrimal gland tumors].

Objective: To investigate the diagnostic value of apparent diffusion coefficient in diffusion weighted imaging at 3.0 T MR for the differentiation in the larcrimal gland tumors. Methods: A total of 73 cases, 36 males and 37 female; mean age 14-81(44±15)years, with lacrimal gland tumors confirmed by pathology in Beijing Tongren Hospital were retrospectively analyzed between January 2011 and April 2016.All cases underwent the preoperative routine MRI and DWI scan, the ADC values were measured in region of interest within the solid zone. The cases were divided into benign and malignant group by the histopathology, according the different pathological categories, the malignant cases were further divided into the epithelial and non-epithelial malignacy. The receiver operating characteristic curve (ROC) was constructed using various cut points of ADC for different parameters to confirm the diagnostic threshold value and evaluate the diagnostic efficacy. Results: There were totally 77 lesions in 73 cases, of which 69 involved unilateral lacrimal gland,4 bilateral lacrimal glands. The mean ADC value of malignant and benign masses in lacrimal gland was (1.36±0.16) and (0.90±0.30)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both(t=-8.319, P<0.01). The mean ADC value of epithelial and non-epithelial malignacy in lacrimal gland was (1.08±0.18) and (0.54±0.09)×10(-3) mm(2)/s respectively. There was significantly statistical difference between the both(t=11.988, P<0.01). The area under the ROC for distinguishing malignant from benign lesions was 0.940. Using an ADC value of 1.275×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 94.4%(34/36), specificity of 82.9%(34/41), accuracy of 88.3%(68/77). The area under the ROC for differentiating non-epithelial from epithelial malignacy was 1.0. Using an ADC value of 0.736×10(-3) mm(2)/s as the threshold value, the best result obtained had a sensitivity of 100%, specificity of 100%, accuracy of 100%. Conclusion: The ADC value is helpful in differentiation among different kinds of tumors in lacrimal masses.

[Reproducibility and comparison study of two methods evaluating the optic nerve subarachnoid space sectional area using MRI].

Objective: To optimize the method of acquiring the ONSAS parameter and to access the repeatability of the new method comparing with the traditional one. Methods: This is a cross-sectional study. Standard operation procedure of an optimized method of acquiring the ONSAS sectional area was made against the defect of the traditional method. Ten healthy volunteers (20 eyes) in different ages were recruited from March 2016 to October. Two times of MRI scan were proceeded with the interval of one week. The optimized and traditional methods were both applied for each scanning. The images were analyzed by two ophthalmologists. The rate of high quality images between two groups was compared with matching chi-square test. The orbital subarachnoid space areas between groups at different locations were compared using analysis of variance of repeated measurement data. The ICC between different scans and different ophthalmologists was calculated. Results: The mean age of the volunteers was 43.8±13.1 years old. Male/Female was 1∶1. The rates of high quality images from the optimized method (100%, 83%, 78%) was higher than those of the traditional method(80%, 78%, 70%). The orbital subarachnoid space area at 3 mm, 9 mm and 15 mm behind the eye ball acquired from the new method(7.2±1.8, 6.1±1.8, 5.9±1.4 mm(2)) were bigger than those of the traditional method (9.0±2.9, 7.6±2.4, 7.1±1.6 mm(2)). Statistical significances were found at 9 mm(F=4.30, P=0.048) and 15 mm(F=5.67, P=0.026) behind the eye ball. The ICC between two different scans (0.879, 0.857, 0.857 vs 0.741, 0.762, 0.639) and two different ophthalmologists (0.864, 0.890, 0.894 vs 0.785, 0.609, 0.753) were higher in the new method group than in the traditional method group. Conclusions: The optimized method of acquiring the parameters of optic nerve subarachnoid space is easier to get the sectional cross area. The measuring reproducibility is better than the traditional one. (Chin J Ophthalmol, 2017, 53: 440-444).

[Value of DCE-MRI and DWI in the differential diagnosis of inflammatory pseudotumor and lymphoma in the lacrimal gland].

Objective: To evaluate the value of dynamic contrast-enhanced MR (DCE-MRI) and diffusion weighted MR (DWI) in differential diagnosis of inflammatory pseudotumor and lymphoma in the lacrimal gland. Methods: In this retrospective study, a total of 24 cases of inflammatory pseudotumor and 22 cases of lymphoma in the lacrimal gland at Beijing Tongren Hospital confirmed by histological results were enrolled from January 2010 to January 2015.DCE-MRI and DWI were performed in these cases, and the type of time-signal intensity curve (time-intensity curve, TIC), the peak contrast index (CIpeak), maximum enhancement ratio (ERmax), washout ratio (WR) and ADC value were analyzed.Differences of these parameters between inflammatory pseudotumor and lymphoma in the lacrimal gland was evaluated by independent samples t test or Mann-Whitney U test.The receiver operating characteristic analysis was used to evaluate the utility of these parameters in discriminating the two diseases. Results: Type of TIC, CIpeak, WR, ERmax and ADC values were statistically different (all P<0.05) between the inflammatory pseudotumor and lymphoma in the lacrimal gland.ERmax, CIpeak and ADC values of inflammatory pseudotumor were greater than those of lymphoma, but the WR values of inflammatory pseudotumor was less than those of lymphoma.The area under the ROC of the CIpeak, WR, ERmax and ADC values was 0.68±0.08, 0.70±0.08, 0.70±0.08, 0.84±0.81 respectively.Using an ADC(b=0, 1000) value of 1.005×10(-3) mm(2)/s as the diagnostic threshold, the sensitivity, specificity and accuracy to differentiate benign lesions from malignant lesions were 84.2%, 65.0% and 75.0% respectively.The diagnostic ability of DWI combined with DCE-MRI was superior to that of DCE-MRI(P=0.000) or DWI alone(P=0.008) with overall sensitivity, specificity and accuracy of 86.3%, 87.5% and 86.9%. Conclusion: DCE-MRI and DWI may improve the diagnostic accuracy in differentiation of the inflammatory pseudotumors and lymphomas in the lacrimal gland, and play an important role in differentiation among them.

[Study of optic radiations in patients with primary open-angle glaucoma with diffusion tensor imaging].

Objective: To study the alteration of the optic radiations in patients with primary open-angle glaucoma (POAG) by diffusion tensor imaging (DTI) and tractography, and to reveal the correlation between the DTI derived parameters and the severity of the disease. Methods: A total of 24 patients with POAG and 20 age- and gender-matched healthy controls were enrolled in this study from January 2011 to June 2013.All subjects underwent ophthalmoscopy, standard automatic perimetry, intraocular pressure measurement and MRI scanning.All the eyes of POAG patients were evaluated by Hodapp-Anderson-Parrish (HAP) system.Then the stages of bilateral eyes were added together to evaluate the disease severity.Tractography was used to measure the fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD) of the optic radiations of these subjects.The results of the two groups were compared.Partial correlation was then used to reveal the correlation between these derived DTI parameters and the severity of POAG. Results: Compared with health controls, POAG patients showed significant decreased FA (t=-3.299, P=0.002) and AD (t=-2.485, P=0.013), increased RD (t=2.365, P=0.018) in optic radiation .The alteration of MD was not significant (t=0.719, P=0.454). Mean FA values of the optic radiations were negatively correlated with POAG stages (r=-0.643, P= 0.001), while mean RD values (r=0.570, P= 0.004) and mean MD values (r= 0.448, P= 0.028) were positively correlated with POAG stages.No correlation between AD values and severity of POAG was found. Conclusion: In the optic radiations of POAG patients, the FA values and AD values decrease, while RD values increase, indicating the fiber integrity changes.The alterations of FA, RD and MD are correlated with disease severity.

Association between GSTM1, GSTT1, and GSTP1 polymorphisms and gastric cancer risk, and their interactions with environmental factors.

Glutathione S-transferase (GST) is an important member of phase II metabolic enzymes; GSTM1, GSTT1, and GSTP1 belong to three subfamilies of the GST enzyme. Polymorphisms in GSTM1, GSTT1, and GSTP1 could affect detoxification processes, and increase individuals' susceptibility to cancers. We aimed to investigate the association between GSTM1, GSTT1, and GSTP1 polymorphisms and the risk of gastric cancer in a Chinese population. In addition, we also examined the effect of gene-environmental interactions, and their effect on risk of this cancer. Between July 2013 and June 2015, we recruited 242 gastric cancer patients and 396 healthy controls for our study. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to characterize genetic polymorphisms in GSTM1, GSTT1, and GSTP1. We observed that the Val/Val genotype of GSTP1 was associated with increased risk of gastric cancer when compared with the Ile/Ile genotype (OR = 3.19, 95%CI = 1.84-5.56). Moreover, the Val allele of GSTP1 was associated with higher susceptibility to gastric cancer as compared with the Ile allele (OR = 1.52, 95%CI = 1.19-1.93). However, GSTM1 and GSTT1 polymorphisms did not affect the development of gastric cancer. In conclusion, our study indicated that GSTP1 Ile105Val, but not GSTM1 and GSTT1 polymorphisms, was associated with risk of gastric cancer.

Analysis of ADH1B Arg47His, ALDH2 Glu487Lys, and CYP4502E1 polymorphisms in gastric cancer risk and interaction with environmental factors.

Gastric cancer is the fourth commonly diagnosed cancer and the second most frequent cause of cancer death worldwide. Genetic variations in ADH1B and ALDH2 may alter the function and activity of the corresponding enzymes, leading to differences in acetaldehyde exposure between drinkers. Cytochrome P4502E1 (CYP4502E1) is a phase I enzyme that plays an important role in metabolizing nitrosamine compounds and the bioactivation of procarcinogens. During the period of July 2013 to July 2015, 246 patients and 274 controls were enrolled from the First Affiliated Hospital of Jinan University. In the codominant model, the AA genotype of ALDH2 Glu487Lys significantly elevated the risk of gastric cancer in comparison with the GG genotype of ALDH2 Glu487Lys. In the recessive model, the AA genotype of ALDH2 Glu487Lys significantly increased the risk of gastric cancer compared to the GG+GA genotype (OR = 2.34 95%CI = 1.02-5.70). We found in the codominant model that individuals harboring the C2/C2 genotype of CYP4502E1 had a higher risk of developing gastric cancer than those with the C1/C1 genotype. In addition, in the recessive model, we found that the C2/C2 genotype correlated with an elevated risk of gastric cancer in comparison with the C1/C1+C1/C2 genotype (OR = 4.90, 95%CI = 2.04-13.51). However, no significant relationship was measured between ADH1B Arg47His and gastric cancer risk. In summary, the results of our study indicate that ALDH2 Glu487Lys and CYP4502E1 polymorphisms could be risk factors for the development of gastric cancer in the Chinese population.

[Manganese enhanced magnetic resonance imaging investigation in the central auditory pathway of the cat].

OBJECTIVE: To compare enhancement of the central auditory pathway in cats receiving auditory stimulation between manganese enhanced magnetic resonance imaging (MEMRI) with intraperitoneal manganese injection route and MEMRI with intratympanic manganese injection route, and investigate the optimal method for displaying enhancement of the central auditory pathway. METHODS: Twenty-seven normal hearing adult cats were randomly divided into three groups, receiving intraperitoneal manganese injection, left intratympanic manganese injection or left intratympanic gadolinium injection respectively.All cats received white noise stimulation of 80 dB in twenty-four hours after injection.Three dimensionally coronal T1-weighted imaging of the cat brain was obtained with an animal dedicated MRI scanner.The signal noise ratios (SNRs) of bilateral cochlear nuclei (CN), dorsal nuclei of the trapezoid bodies (DNTB), caudal colliculi (CC) and auditory cortices (AC) were measured on reconstructed images and compared. RESULTS: Obvious increased SNRs on both sides were shown in intraperitoneal mangasese injection group while left predilection was shown in intratympanic manganese injection group: left CN 45.7±6.0, 37.4±11.9, 23.9±2.7, F=17.694, P=0.000; left DNTB 50.5±11.2, 37.1±11.2, 27.6±7.3, F=11.781, P=0.000; left CC 37.6±3.9, 22.6±3.1, 17.9±0.7, F=111.898, P=0.000; left AC 27.7±2.5, 17.3±2.3, 14.5±1.0, F=105.132, P=0.000; right CN 42.7±8.3, 23.9±3.0, 22.7±2.1, F=41.492, P=0.000; right DNTB 44.1±8.3, 21.9±3.0, 23.9±4.0, F=27.862, P=0.000; right CC 38.0±4.0, 21.9±3.0, 17.6±0.9, F=120.032, P=0.000; right AC 26.7±3.4, 17.1±2.9, 14.9±1.3, F=64.587, P=0.000.Compared with the left intratympanic gadolinium injection group, the intraperitoneal manganese injection group showed higher SNRs in bilateral CN and CC (P<0.05), and the left intratympanic manganese injection group showed higher SNRs in left CN, AC and bilateral CC.The SNRs of right CN, bilateral DNTB, CC and AC were significantly higher in the intraperitoneal manganese injection group than those in the left intratympanic manganese injection group (P<0.05). CONCLUSION: MEMRI with intraperitoneal manganese injection might be the optimal method for displaying enhancement of the central auditory pathway in cats receiving auditory stimulation.

Radiation dose reduction in temporal bone CT with iterative reconstruction technique.

BACKGROUND AND PURPOSE: Iterative reconstruction of CT images is characterized by reduced image noise and may allow reduction in radiation exposure. We investigated the influence of an IRT technique on image quality and radiation dose savings when applied to temporal bone CT. MATERIALS AND METHODS: Based on the typical image quality level of adult subjects using routine radiation dose and FBP, an exsomatized cadaveric head with CNR characteristics closest to the level of clinical subjects was identified. Cadaver acquisitions were performed at multiple levels of tube current exposure. Reconstructions were performed using FBP and IRT (iDose), with multiple iDose levels applied for each acquisition. Transverse and coronal reformations of all reconstructions were evaluated subjectively and objectively. Phantom tests were performed to validate the protocol optimizations with iDose, specifically the spatial resolution relative to routine dose acquisitions. Finally, the results of protocol optimization with iDose were clinically validated in 50 patients. RESULTS: At the same radiation dose, the image CNR of iDose reconstructions was higher than that of FBP and progressively increased with higher iDose levels. The combination of 100 mAs/section and iDoseL5 was the lowest dose that met the requirements for diagnostic acceptability, with CNR slightly higher than our routine institution protocol of 200 mAs/section with FBP reconstruction. Spatial resolution characteristics were similar between FBP and iDose at all different strengths. The findings were consistent among the cadaver, phantom, and clinical acquisitions. CONCLUSIONS: The iDose IRT can help reduce radiation dose of temporal bone CT by 50% relative to routine institution protocols with FBP, while maintaining diagnostic image quality.

MR evaluation of sinonasal angiomatous polyp.

BACKGROUND AND PURPOSE: SAP is a rare lesion of the sinonasal cavity, which may be misdiagnosed as a benign or malignant neoplasm. The purpose of our study was to comprehensively evaluate the MR imaging features of SAP. MATERIALS AND METHODS: Forty patients with SAP confirmed pathologically were retrospectively reviewed. Of the 40 patients undergoing MR imaging, 39 had postcontrast T1WI; 30, DCE MR imaging; and 17, DWI. The image features assessed included the location, shape, margin, size, signal intensity, and enhancement pattern on DCE MR imaging and ADC maps. RESULTS: All 40 SAPs originated from the maxillary sinus, but the lesions frequently extended into the ipsilateral nasal cavity (38/40), toward the choana (19/40), and into the nasopharynx (8/40). The lesions demonstrated hypointensity on T1WI and heterogenous hyperintensity on T2WI. All 40 lesions showed a peripheral hypointense rim on T2WI. Postcontrast MR imaging revealed marked heterogeneous nodular and patchy enhancement. Progressive enhancement was found on DCE MR imaging in 30 cases. The TIC showed a steady enhancement pattern in 3 cases, a rapidly enhancing and slow washout pattern in 6 cases, and a rapidly enhancing and rapid washout pattern in 21 cases. On DWI, the mean ADC value was (1.40 ± 0.20) × 10(-3) mm(2)/s. CONCLUSIONS: Distinctive features of SAP on conventional MR imaging include internal heterogeneous hyperintensity and a peripheral hypointense rim on T2WI, as well as strong nodular and patchy enhancement on postcontrast MR images. The progressive enhancement on DCE MR imaging can also suggest the diagnosis.

Experimental study and optimization of scan parameters that influence radiation dose in temporal bone high-resolution multidetector row CT.

BACKGROUND AND PURPOSE: MDCT has some specific scan parameters that may systematically increase or decrease radiation dose to patients. This study explored the scan protocol parameters that impact radiation dose in temporal bone MDCT and determined the optimal scan parameters that balance radiation dose with diagnostic image quality. MATERIALS AND METHODS: Using exsomatized cadaveric heads, traditional axial scanning, and helical scanning were performed with different detector collimations. Helical scans of the same scan region were then acquired by using the determined optimal detector collimation and various tube voltages, whereas other scan parameters remained fixed. Next, the scans were repeated by using various tube current-time products by using the determined optimal tube voltage. Last, with fixed tube current-time product, the scans were repeated with various pitches. All thin-section, helically acquired scans were reformatted to axial and coronal images with respect to the relevant scanning baseline. In each of the image volumes, the mean and SD HU values in regions of interest were measured in the central section of the internal auditory canal, and CNR values were calculated. RESULTS: In agreement with theory, wider detector collimations such as 16 × 0.625 mm and 64 × 0.625 mm were associated with lower radiation doses than narrower collimations due to their lower overbeaming and higher geometric efficiency. In helical scanning, the detector collimation of 16 × 0.625 mm had higher image quality and the minimum DLP. Axial and coronal images acquired by using a 140-kVp tube voltage had significantly lower noise than scans acquired at 120 or 80 kVp with equivalent volume CT dose index. Diagnostic image quality was achieved when using a minimum tube current-time product of 120 mAs. Noise, CNR, and dose were jointly optimized with a pitch of 0.685. CONCLUSIONS: Temporal bone CT scanning parameters may be optimized by following a systematic procedure that allows for the optimization of diagnostic image quality and the minimization of radiation dose. One such procedure for a particular 64-section MDCT scanner has been presented.