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  • Anatomic evaluation of vitreous surgery of idiopathic macular hole with optical coherence tomography

    Purpose To evaluate the surgical effect of idiopathic macular hole (IMH),with optical coherence tomography (OCT). Methods To measure the diameter of holes and hole halos,the thickness of hole in edge,the changes of hole pattern in 19 cases (19 eyes) with IMH using OCT. Results By quantitatively measuring,OCT showed that after surgery the mean hole diameter lessened from (570.95plusmn;264.59 )mu;m to (337.05plusmn;335.95)mu;m.The mean diameter of hole halo lessened from (1043.53plusmn;278.80)mu;m to (695.00plusmn;483.00)mu;m and the mean thickness of the hole edge thinned from (389.78plusmn;60.58)mu;m to (298.78plusmn;109.80)mu;m.In 17 eyes the holes become closed or reduced in size or the hole halo,and thinned in hole edge.The anatomic successful rate of the surgery is 89%. Conclusion OCT can objectively,accurately and effectively judge the anatomic effect of IMH surgery. (Chin J Ocul Fundus Dis,2000,16:71-138)

    Release date:2016-09-02 06:05 Export PDF Favorites Scan
  • Analysis of changes of visual acuity, multifocal electroretinogram and optical coherence tomogram before and after successful idiopathic macular hole surgery

    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)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • A Denoising Method for Low-dose Small-animal Computed Tomography Image Based on Globe Dictionary Learning

    Considering the survival rate of small animals and the continuity of the experiments, high-dose X-ray shooting process is not suitable for the small animals in computed tomography (CT) experiments. But the low-dose process results with images might be polluted by noises which are not conducive for the experiments. In order to solve this problem, we in this paper introduce a global dictionary learning based denoising method to apply the promotion of the low dose CT image. We at first adopted the K-means singular value decomposition (K-SVD) algorithm to train a global dictionary based on the high dose CT image. Then, the noise image could be decomposed into sparse component which was free from noise through the orthogonal matching pursuit (OMP) algorithm. Finally, the noise-free image could be achieved by reconstructing the image only with its sparse components. The experiments results showed that the method we proposed here could decrease the noise efficiently and remain the details, and it would help promote the low dose image quality and increase the survival rate of the small animals.

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  • Clinical application of three-dimensional technique in segmentectomy

    More and more relevant research results show that anatomical segmentectomy has the same effect as traditional lobectomy in the surgical treatment of early-stage non-small cell lung cancer (diameter<2.0 cm). Segmentectomy is more difficult than lobotomy. Nowadays, with the promotion of personalization medicine and precision medicine, three-dimensional technique has been widely applied in the medical field. It has advantages such as preoperative simulation, intraoperative positioning, intraoperative navigation, clinical teaching and so on. It plays a key role in the discovery of local anatomical variation of pulmonary segment. This paper reviewed the clinical application of three-dimensional technique and briefly described the clinical application value of this technique in segmentectomy.

    Release date:2021-06-07 02:03 Export PDF Favorites Scan
  • Predictive Value of Preoperative 64 MDCT for Stage Ⅳ Gastric Cancer

    Objective  To evaluate the accuracy of preoperative 64 multidetector spiral computed tomography (MDCT) in the diagnosis of stage Ⅳ gastric cancer. Methods The data of patients with stage Ⅳ gastric cancer between July 2007 and April 2008 were collected. Twenty-nine patients underwent preoperative 64 MDCT were retrospectively analyzed. All computed tomography scans were prospectly analyzed by 2 abdominal radiologists separately. Pathological tumor stage was based on TNM stage according to the revised Japanese Classification of Gastric Carcinoma from the Japanese Gastric Cancer Association. All CT results were compared with clinical, surgical and histopathologic results. Results The 65.2% (15/23), 47.8% (11/23) and 70.8% (17/24) of the stage Ⅳ patients were accurately predicted of T, N and M stage, respectively. Moreover, 58.6% (17/29) of the stage Ⅳ patients were accurately predicted of TNM stage. But 6/9 cases with peritoneal metastases were not detected by preoperative 64 MDCT. Conclusion The 64 MDCT is a promising technique for detection and preoperative staging of stage Ⅳ gastric cancer. It was difficult to detect peritoneal metastases, but it may not increase the rate of exploratory laparotomy.

    Release date:2016-09-08 11:47 Export PDF Favorites Scan
  • Observation of vortex venous anastomosis in central serous chorioretinopathy

    Objective To observe the anastomotic status of the vortex veins in patients with central serous chorioretinopathy (CSC). MethodsA cross-sectional study of clinical practice. From July 2021 to July 2022, 50 cases (50 eyes) of monocular CSC patients diagnosed through ophthalmic examination at the First Affiliated Hospital of Zhengzhou University were included in the study. Among them, there were 37 males (74.0%, 37/50) and 13 females (26.0%, 13/50), with the mean age of (44.30±9.59) years old. The course of disease from the onset of symptoms to the time of treatment was less than 3 months. The affected eye and contralateral eye of CSC patients were divided into the affected eye group and contralateral eye group, respectively. Fifty healthy volunteers of the same age and gender were selected as the normal control group with 50 eyes. The macular area scanning source optical coherence tomography (OCT) vascular imaging examination was performed with Visual Microimaging (Henan) Technology Co., Ltd. VG200D. Horizontal watershed vortex veins anastomosis rate and asymmetric vortex-venous dilation rate were observed by en face OCT. The device comes with software to calculate the central foveal choroidal thickness (SFCT), mean choroidal thickness (MCT), and choroidal vascular index (CVI). One-way analysis of variance and χ2 test were used to compare the three groups. When variances were unequal between groups, nonparametric tests were performed. ResultsThe SFCT values of the affected eye group, contralateral eye group, and normal control group were (567.12±129.02), (513.26±133.17), (327.64±97.40) μm, respectively; MCT were (407.38±97.54), (388.24±94.13), (275.46±60.55) μm, respectively; CVI were 0.34±0.05, 0.32±0.04, and 0.27±0.04, respectively; anastomosis rates of vortex veins were 98% (49/50), 78% (39/50), and 40% (20/50), respectively; asymmetric dilation rates of vortex veins were 96% (48/50), 88% (44/50), and 48% (24/50), respectively. The differences of SFCT (F=53.974), MCT (Z=51.415), CVI (F=28.082), vortex vein anastomosis rate (χ2=43.056), asymmetric dilation rate of vortex veins (χ2=37.728) among three groups were statistically significant (P<0.001). Compared with the contralateral eye group, the SFCT, MCT, CVI, vortex vein anastomosis rate, and vortex vein asymmetric dilation rate in the affected eye group were significantly higher than those in the contralateral eye group. Among them, the differences of SFCT (t=2.054), CVI (t=2.211), and vortex vein anastomosis rate (χ2=9.470) were statistically significant (P<0.05); the differences of MCT (Z=7.490), asymmetric dilation rate of vortex veins(χ2=2.714) were not statistically significant (P=1.000, 0.140). ConclusionsSFCT, MCT, and CVI in the affected and contralateral eyes of monocular CSC patients significantly increase. The anastomotic rate and asymmetric dilation rate of the vortex vein in the opposite eye were lower than those in the affected eye.

    Release date:2023-05-18 10:05 Export PDF Favorites Scan
  • Diagnostic Value and Post-operative Evaluation of MRA and CTA in Vascular Lesions of Low Extremity Caused by Crush Injury after Earthquake

    目的:探讨磁共振血管造影(MRA)以及计算机断层扫描血管成像(CTA)对地震挤压伤下肢血管病变的临床价值。方法:对5·12汶川大地震中我院收治的已确诊为地震挤压伤致双下肢横纹肌溶解症3例患者进行双下肢MRA检查,并对严重挤压伤及下肢毁损,并行截肢的另三名患者进行术后CTA检查。对MRA图象双下肢动脉进行回顾性分析,总结MRA征象,同时总结截肢术后患者CTA表现及临床价值,并评价二者检查在挤压伤所至横纹肌溶解症的临床诊治中的作用。结果:3例未行截肢患者MRA双下肢主要动脉未见确切狭窄及闭塞征象,管腔内未见充盈缺损影。3例已行截肢患者可见残余肢体的明显肿胀,双侧髂血管以及部分截断肢体远端血管内见止血弹簧钢圈影像,部分截断肢体远端动脉分支变细。截断血管未见再通,周围无渗血改变。结论:MRA、CTA能直观显示双下肢动脉损伤及术后情况,在临床应用中各有优势和局限性。对二者的合理选择能为临床诊治提供有利信息。

    Release date:2016-09-08 09:54 Export PDF Favorites Scan
  • CT 扫描诊断下胫腓联合损伤的应用评价

    目的 评估CT 扫描诊断下胫腓联合损伤的应用价值,为临床诊断下胫腓联合损伤提供有效的诊断方法。 方法 2007 年3 月- 2009 年2 月,收治68 例闭合性踝部骨折患者。男45 例,女23 例;年龄18 ~ 63 岁,平均36.7 岁。Lange-Hanson 分型:旋前外旋型23 例,旋前外展型19 例,旋后外旋型12 例,旋后内收型11 例,垂直压缩型3 例。Denis-weber 分型:A 型7 例,B 型28 例,C 型33 例。受伤至手术时间6 ~ 144 h,平均94 h。术前常规摄X 线片及行CT扫描诊断下胫腓联合损伤情况。采取切开复位内固定治疗,术中探查下胫腓联合损伤情况并作为“金标准”,与术前X 线片和CT 扫描结果进行统计学比较分析。 结果 术中手术探查46 例存在下胫腓联合损伤,22 例未见损伤。术前X 线片诊断下胫腓联合损伤真阳性25 例,真阴性16 例,假阳性6 例,假阴性21 例,灵敏度54.34% ± 14.38%,特异度72.72% ±18.60%,准确度60.29% ± 11.62%,阳性预测值80.64% ± 13.89%,阴性预测值43.24% ± 20.34%;术前CT 扫描诊断真阳性43 例,真阴性21 例,假阳性1 例,假阴性3 例,灵敏度93.47%±7.11%,特异度95.45% ± 8.66%,准确度94.11% ± 5.58%,阳性预测值97.72% ± 4.39%,阴性预测值87.50% ± 13.21%;CT 扫描各指标均明显高于X 线片(P lt; 0.05)。Kappa 指数显示CT 扫描与手术探查结果存在一致性,可靠性高;X 线片可靠性低。 结论 单纯根据X 线片诊断下胫腓联合损伤可靠性低,CT 扫描诊断下胫腓联合损伤可靠性高、真实性好,能够提供重要的临床参考价值。

    Release date:2016-09-01 09:08 Export PDF Favorites Scan
  • 国际抗癫痫联盟诊断方法委员会儿科手术治疗协作组报告——诊断性检查在可外科治疗的儿童癫痫中的应用

    对于经过严格筛选的儿童耐药性局灶性癫痫病例, 外科手术是取得无痫性发作的成功手段。医学技术的发展使癫痫患者可以获得更精准的术前评估, 同时患者获得癫痫外科手术治疗的机会也有所增加。如今已在临床应用的癫痫灶评估方法不仅耗费资源而且在特定病例中不起作用, 抑或是副作用大。因此有必要及时制定标准化的术前评估流程。各项检查在特定临床病理类型的病例中的作用尚缺乏1级或2级证据支持。基于这一现状, 国际抗癫痫联盟(ILAE)的诊断与儿科学组的儿童癫痫外科协作组将各成员间的共识总结为专家建议发表。旨在减少将各项检查的利用不足, 同时促进临床更灵活地运用各项检查, 使现有的儿童癫痫中心尽可能标准化地进行癫痫的术前评估。

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  • Correlation study of alterations of macular outer retinal reflectivity and the associations with macular vessel density in nonproliferative diabetic retinopathy

    ObjectiveTo observe alterations of macular outer retinal reflectivity (ORR) and the associations with macular vessel density in patients with nonproliferative diabetic retinopathy (NPDR). Methods A retrospective cross-sectional study. From August 2021 to March 2022, a total of 63 NPDR patients with 63 eyes (NPDR group) diagnosed by Department of Ophthalmology of Guangdong Provincial People's Hospital were included in the study. There were 39 males with 39 eyes and 24 females with 24 eyes. Age was 60 (52, 68) years. A total of 66 eyes of 66 healthy volunteers matching age and sex were selected as the control group. Among them, 40 men had 40 eyes and 26 women had 26 eyes. Age was 58 (52, 67) years. Optical coherence tomography (OCT) and OCT angiography (OCTA) were performed in all affected eyes. Image J software was used to calculate ORR, including the optical density of ellipsoid zone (EZ), photoreceptor outer segment (OS), photoreceptor inner segment (IS) and outer nuclear layer (ONL) by OCT examination. The sampling sites were horizontal and vertical scanning of the fovea of the macula on 500 μm (nasal500, temporal500, superior500, inferior500), 1 000 μm (nasal1 000, temporal1 000, superior1 000, inferior1 000) and 2 000 μm (nasal2 000, temporal2 000, superior2 000, inferior2 000). The software automatically divided the retina within 6 mm of the macular fovea into the fovea with a diameter of 1 mm, the parafovea with a diameter of 1-3 mm, and the perifovea with a diameter of 3-6 mm by macular OCTA examination. The blood density of superficial capillary plexus and deep capillary plexus in different zones in the macular area were measured by the built-in software of the device. Spearman correlation analysis was used to analyze the correlation between ORR and blood flow density. ResultsCompared with the control group, retinal reflectivity of EZ in NPDR group was significantly decreased at other sites except the fovea, retinal reflectivity of OS was significantly decreased at nasal2 000, temporal2 000, superior2 000 and superior1 000; retinal reflectivity of IS was significantly decreased at superior1 000, superior500 and inferior500. The retinal reflectivity of ONL in macular fovea was significantly decreased, and the differences were statistically significant (P<0.05). The ORR was positively correlated with blood flow density, and the correlation coefficient in NPDR group was lower than that in control group. The results of multifactor linear regression analysis showed that the superior and temporal ORR were correlated with blood flow density (P<0.05). ConclusionsCompared with the control group, ORR is reduced and less correlated with vessel density in NPDR patients. ORR is more affected by retinal blood flow density in temporal and superior parts.

    Release date:2023-11-16 05:57 Export PDF Favorites Scan
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