Objective To investigate the early influences of laser photocoagulation on macular retinal thickness in diabetic retinopathy(DR). Methods Optic coherence tomography examination was performed in 30 eyes with DR(phase Ⅲ~Ⅳ) before, and on the 3rd day and the 7th day after photocoagulation respectively. The thickness of neuroretina and pigment epithelium were measured in the areas of fovea macula and 750 μm from fovea macula. Results Three days after photocoagulation, significant thickening of neuroretina was observed in the fovea macula, which is positively related with age, fasting blood sugar and duration of DR. There was no significant changes in the thickness of pigment epithelium in macula and in the thickness of neuroretina 750 μm from fovea macula. Conclusion Significant thickening of neuroretina in fovea macula in DR early after photocoagulation reveals progressed macular edema induced by photocoagulation which is positively related with age, fasting blood sugar and duration of DR. (Chin J Ocul Fundus Dis, 2002, 18: 31-33)
Lung diseases such as lung cancer and COVID-19 seriously endanger human health and life safety, so early screening and diagnosis are particularly important. computed tomography (CT) technology is one of the important ways to screen lung diseases, among which lung parenchyma segmentation based on CT images is the key step in screening lung diseases, and high-quality lung parenchyma segmentation can effectively improve the level of early diagnosis and treatment of lung diseases. Automatic, fast and accurate segmentation of lung parenchyma based on CT images can effectively compensate for the shortcomings of low efficiency and strong subjectivity of manual segmentation, and has become one of the research hotspots in this field. In this paper, the research progress in lung parenchyma segmentation is reviewed based on the related literatures published at domestic and abroad in recent years. The traditional machine learning methods and deep learning methods are compared and analyzed, and the research progress of improving the network structure of deep learning model is emphatically introduced. Some unsolved problems in lung parenchyma segmentation were discussed, and the development prospect was prospected, providing reference for researchers in related fields.
ObjectiveTo observe and classify the characteristics of optical coherence tomography (OCT) for several common diseases which could lead to submacular choroidal neovascularization (CNV), and to provide the warrant to make the differential diagnosis and treatment of CNV.MethodsThe data of OCT of 165 patients (187 eyes) with CNV due to AMD, CEC, high myopia and ICNV diagnosed by fundus photography and fundus fluorescein angiography (FFA) were retrospectively analyzed, and the images of OCT were classified considering the results of FFA, and the characteristics of different types of the images were sumerized.ResultsWell-defined fusiform thickening of retinal pigment epithelial (RPE) and choriocapillary layer in CNV with well-defined border (60 eyes), dispersed backscattering increase in poorly-defined CNV (101 eyes), optic darkspace beneath RPE layer in serous detachment of RPE layer (19 eyes), quickly decreased high backscattering region under RPE layer in hemorrhagic detachment of RPE layer (11 eyes), slight to moderate backscattering region between RPE layer in fibrovascular detachment of RPE layer (10 eyes), and detachment of neurepithelial layer from RPE layer with the optic darkspace between the layers in detachment of neurepithelial layer (45 eyes) were observed.ConclusionsThe images of OCT for the common diseases which could lead to submacular choroidal neovascularization may be divided into 6 types. Analyzing the characteristics of images of OCT is helpful in differential diagnosis and treatment of CNV. (Chin J Ocul Fundus Dis, 2005,21:69-73)
Objective To observe the changes of visual acuity、multifocal electroretinogram (mfERG) and optical coherence tomogram（OCT）before and after successful idiopathic macular hole (IMH) surgery, and evaluate the efficiency of the IMH surgery. Methods A total of 28 eyes of 28 patients with IMH who underwent vitrectomy during February 2001 and May 2002 in our hospital were collected. visual acuity, mfERG, and OCT were examined preoperatively and 1, 3, 6, and 12 months postoperatively, respectively. The results were analyzed statistically compared with 33 eyes in control group. Results (1) OCT showed that 27 eyes (96.43%) had anatomic closure of the macular hole 1 month after the surgery without recurrence in 12 months. Just 1 eye (3.57%) failed in the closure within 1 year. (2) The visual acuity was much higher in the eyes 1 year after surgery, especially within 6 months postoperatively, than that before the vitrectomy（P＜0.01）. (3) Before the operation, the mfERG topographies of IMH eyes seem like volcanoes becase the response densities of wave P1 of ring 1 and ring 2 were lower than control group while the other three rings kept in normal. The central peaks of mfERG topographies reappeared little by little during 1 year after the surgery, and the response densities of wave P1 of ring 1 and ring 2 were higher than before, which was still lower than the control group（P＜0.05）. (4) The thickness of neuroepithelial layer (NEL) of fovea measured by OCT of 27 eyes with anatomic closure was no longer varied and kept lower than control group throughout the follow-up time （P＜0.05）. (5) One year after the operation, there were positive correlations among visual acuity, mfERG and NEL（P＜0.05）. Conclusions Vitrectomy is useful for IMH, which could be evaluated by visual acuity mfERG and OCT efficiently. The three factors had consistency. (Chin J Ocul Fundus Dis，2004，20：221-225)
目的:探讨外伤性颅内迟发性血肿CT表现特点和规律,为临床即时诊治提供可靠依据。方法:对136例外伤性颅内迟发性血肿患者首次CT及伤后迟发性血肿发生时间进行分析。结果:外伤性颅内迟发性血肿患者多数首次CT检查,可仅表现为蛛网膜下腔出血、脑肿胀、脑挫裂伤和颅骨骨折;颅内迟发性血肿发生的高峰期为伤后24～72小时。结论:外伤性颅内迟发性血肿首次CT检查多有异常,但无颅内血肿者,应在24~72小时内进行CT复查,以发现颅内迟发性血肿,方不至贻误诊治。
ObjectiveTo investigate the course of the idiopathic macular hole (IMH) clinically diagnosed as at stage Ⅰ-Ⅳ by optical coherence tomography (OCT), and analyze the relationship between the posterior vitreous detachment (PVD) and the course of IMH. MethodsHadn′t undergone any operation, periodical OCT were performed on 72 eyes of 58 patients with IMH at stage Ⅰ-Ⅳ confirmed by Gass standard and the features of OCT images.ResultsThe longest follow-up period was 43 months (average 13.4 months), and the examine times of OCT on each eye were between twice to 10 times (average 4.7 times). During the followup period, 23 eyes were in stage I in which 9 (39.1%) developed to stage II and 2 had recovered normal curve of fovea after PVD; 19 were in stage II in which 13 (68.4%) developed to Ⅲ-Ⅳ and 1 had closed hole after PVD; 11 were in stage III in which 5 (45.5%) developed to stage IV and 1 had partly closed hole 12 months later. The images of OCT showed that the process of macular hole was consistent with the course that vitreous depart from retina from the circumference of fovea till entire posterior detachment.Fifteen affected eyes in this series of patients had undcrygong surgical treatment due to serious progression of IMH in follow-up period. ConclusionsThere is a close relationship between the formation and development of macular hole and the occurrence of PVD. OCT can show the progress of the macular hole directly and offer an important technique in diagnosis, classification and surgical treatment of IMH. (Chin J Ocul Fundus Dis, 2005,21:79-82)
ObjectiveTo explore the application of pulmonary ventilation and perfusion imaging (V/P SPECT/CT) in quantitative evaluation of ventilation and perfusion function and its potential value in guiding local treatment of lung in patients with asthma.MethodsA total of 20 patients with asthma were included in this study. All patients underwent V/P SPECT/CT and pulmonary function test, and symptoms were assessed by the ACT questionnaire. Patients were graded for degree of airway obstruction according to V/ P SPECT/CT image visual scoring criteria. The comprehensive lung function (%) of the patients was quantitatively evaluated by combining the ventilation and perfusion defect of each lung segment in V/P imaging. The correlation between the degree of airway obstruction, comprehensive lung function, pulmonary function test and ACT score was analyzed.ResultsV/P SPECT/CT imaging can be used to grade the degree of airway obstruction in asthma patients (0-3 grade). Airway obstruction grading by V/P SPECT/CT visual score was associated with predictive forced expiratory volume in one second (FEV1%pred) of patients (r=–0.74, P<0.001). V/P SPECT/CT can also comprehensively evaluate ventilation and perfusion function in patients with asthma, and comprehensive lung function measured by this method was also correlated with FEV1%pred (r=0.629, P=0.003). V/P SPECT/CT can be used to quantitatively analyze the percentage of ventilation and perfusion function in each lung lobe. Compared with V/P SPECT/CT results, the CT volume overestimates the contribution in the upper lobes, and underestimates the lower lobes contribution to overall function.ConclusionsV/P SPECT/CT can be used as a new method to directly reflect the degree of airway obstruction in patients with asthma. Moreover, it can comprehensively and quantitatively evaluate the ventilation and perfusion function of asthma patients. V/P SPECT/CT can also be used to evaluate lobe function in patients with asthma, helping to identify the heterogeneity of changes in pulmonary function in patients with asthma, and has potential value for future treatment targeting specific areas of the lung.
Objective To observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with macular edema, and investigate relationship between the retinal thickness at the central fovea and the best corrected visual acuity. Methods Fourty-seven patients (54 eyes) with macular edema diagnosed by direct and indirect ophthalmoscopy, three mirror contactlens, or fundus fluorescein angiography (FFA) underwent OCT which was also performed on 50 healthy individuals as the control. The examination focused on the horizontal and vertical planes crossing the central fovea to measure the thickness of the fovea. The correlation between retinal thickness at the central fovea and best-corrected visual acuity was analyzed, and the images of OCT in the patients with macular edema were classified according to the macular configuration. Results Significant difference of the macular configuration and best-corrected visual acuity was found between the control and macular edema group. Three characteristics were found in the images of OCT in the patients with macular edema: sponge-like retinal swelling in 20 eyes (37.1%), macular cystoid edema in 26 eyes (48.1%), and serous retinal detachment in 8 eyes (14.8%). The statistical analysis showed that there was a negative correlation between the thickness at the central fovea and best-corrected visual acuity of affected eyes (r=-0.569, P=0.000). Conclusions The images of OCT in macular edema include 3 types: sponge-like retinal swelling, macular cystoid edema, and serous retinal detachment. The retinal thickness at the central fovea of the eyes with macular edema was thicker than that of the normal ones, and the thicker the fovea is, the poorer the visual acuity will be. (Chin J Ocul Fundus Dis，2004，20：152-155)