Leukemia is a common, multiple and dangerous blood disease, whose early diagnosis and treatment are very important. At present, the diagnosis of leukemia heavily relies on morphological examination of blood cell images by pathologists, which is tedious and time-consuming. Meanwhile, the diagnostic results are highly subjective, which may lead to misdiagnosis and missed diagnosis. To address the gap above, we proposed an improved Vision Transformer model for blood cell recognition. First, a faster R-CNN network was used to locate and extract individual blood cell slices from original images. Then, we split the single-cell image into multiple image patches and put them into the encoder layer for feature extraction. Based on the self-attention mechanism of the Transformer, we proposed a sparse attention module which could focus on the discriminative parts of blood cell images and improve the fine-grained feature representation ability of the model. Finally, a contrastive loss function was adopted to further increase the inter-class difference and intra-class consistency of the extracted features. Experimental results showed that the proposed module outperformed the other approaches and significantly improved the accuracy to 91.96% on the Munich single-cell morphological dataset of leukocytes, which is expected to provide a reference for physicians’ clinical diagnosis.
Objective To evaluate the visual function before and after photodynamic therapy(PDT) in patients with subfoveal choroidal neovascularization ( CNV) caused by age-related macular degeneration (AMD). Methods Twenty-five consecutive patients (34 eyes) treated with PDT (verteporfin) for subfoveal CNV in age-related macular degeneration diagnosed by fluorescein angiography (FFA), indocyanine green angiography (ICGA) and optical coherence tomography (OCT). Visual function including best corrected visual acuity, contrast sensitivity frequency, binocular function, confusion, stereo-vision, color vision, metamorphopsis and central scotoma were examed before photodynamic therapy and 1 week, 1 month, 3 month after photodynamic therapy. The follow-up time varied from 3 months to 2 years (mean 7.6 months). Results The changes of visual function at the 3rd month after photodynamic therapy revealed improving in 13 eyes (38.24%), without any change in 17 eyes (50.00%), and decreasing in 6 eyes (17.65%). Visual acuity with logMRA improved after photodynamic therapy, but without statistic difference. All spatial contrast sensitivity improved. Contrast sensitivity for spatial frequencies 5 cycles per degree (cpd) was better after photodynamic therapy with significant difference (P=0.045).Binocular function, fusion function, stereo function and color vision were slightly improved without statistic difference. Conclusion Damage of visual function in macular degeneration is many-sided. The treatment of PDT for exudative AMD can improve part visual function. (Chin J Ocul Fundus Dis，2004，20：289-291)
Objective To investigate the degree of retinal developmen t in pret erm infants and compare the electroretinograms between preterm and fullterm in fants. Methods Flash electroretinogram (ERG) were obtained wit h contact lens el ectrodes in one eye from ten preterm infants (10 eyes) and twenty full-term inf a nts (20 eyes) in seven days after birth. The rod cell, cone cell, maximal combi nation, oscillatory potentials, and 30 Hz flicker responses were recorded. Results Compared with the full-term infants, the implicit time of rod cell respon s e (t=3.216，P=0.003) was longer and the amplitudes were lower (t=6.0 50，P=0.000) in the preterm infants; the difference of implicit time of maximal response was not significant (t=0.465，P=0.650; t=1.068，P=0.295), while th e amplitudes dec reased (t=6.584, P=0.000; t=6.649, P=0.000). The a- and b-wav e implicit time of cone response was not differed much between the two groups (t=0.077, P=0.939; t=0.935,P=0.358); the amplitudes was obvious lower in preterm group (t =3 .417，P=0.002；t=6.310，P=0.000); the difference of implicit t ime of 30 Hz flic ker betw een the two groups was not significant (t=3.745，P=0.001). The difference of b/a value of maximal combination response was not obvious between the two groups ( t=0.215, P=0.831). Conclusions The development of retinal function is slower in preterm infants than that in full-term ones．
Purpose To observe the color motion perception of patients with diabetic retinopathy (DR) in very early stage and find a good way to diagnose early DR in time． Methods The motion perceptions of patients with early DR and normal subjects were tested by using equiluminant moving chromatic grating and moving luminance grating generated on VGA monitor in a PC compatible computer and the results were compared with those of electroretinogram(ERG),oscillatory potentials(OPs) and color perception． Results When the two gratings were of equal spatial frequency and equal time frequency,the normal subjects judged that chromatic grating moved faster than luminance grating．Very signifincant differences were detected between blue/yellow grating and black/white grating while the luminance contrast of was 80% and the velocity was 20.2 mm/s or 14.3mm/s(Plt;0.01).The abnormal ratio of color motion perception(69.2%)was higher than that of color vision(43.6%) and ERG OPs(48.9%) when the luminance contrast of black/white grating was 80% and the velocity was 20.2mm/s. Conclusion The test of color motion perception provides new method for diagnosing early DR. (Chin J Ocul Fundus Dis,1998,14:135-138)
ObjectiveTo observe the clinical characteristics of patients with visual impairment caused by fungal sphenoid sinusitis and analyze the influencing factors related to visual prognosis. Methods A retrospective clinical study. From January 2006 to December 2020, 44 patients (55 eyes) with visual impairment caused by fungal sphenoid sinusitis confirmed by imaging and pathological examination in the Department of Ophthalmology of Beijing Tongren Hospital were included in the study. Patients was first diagnosed in the Department of Ophthalmology due to monocular or binocular vision loss, or binocular diplopia, limited eye movement and ptosis. All patients underwent visual acuity examination and fundus color photography. CT examination of paranasal sinus or orbit was performed in 37 cases; magnetic resonance imaging (MRI) of paranasal sinus, brain or orbit was performed in 34 cases. All patients underwent endoscopic sinus opening combined with intrasinus lesion clearance; 14 cases were treated with antifungal drugs after operation. The average follow-up time was 59.61±37.70 months. Comparison of clinical characteristics between invasive and non-invasive fungal sphenoid sinusitis were by χ2 test or Fisher exact test. The influencing factors with P＜0.2 in univariate analysis were selected for multivariate regression analysis. ResultsAmong the 44 patients, there were 19 males and 25 females; the ratio of male to female was 1:1.3; the average age of visual symptoms was 61.48 ± 12.17 years; 23 cases (52.3%, 23/44) suffered from immune dysfunction, including 21 cases of diabetes mellitus. The visual acuity decreased in 33 cases (44 eyes) (75.0%, 33/44). There were 15 cases of binocular diplopia with eye movement disorder (34.0%, 15/44), including 6 cases with visual impairment. The visual acuity of the affected eye was no light perception-0.8. There were 35 cases with headache (79.5%, 35/44). Nasal symptoms were found in 14 cases (31.8%, 14/44). There were 40 and 4 cases of Aspergillus and Mucor infection in sphenoid sinus, respectively. Among the 37 cases who underwent CT examination of paranasal sinus or orbit, there were soft tissue filling in the sinus cavity, including 19 cases of high-density calcification in the sinus cavity (51.4%, 19/37); bone defect of sinus wall were in 24 cases (64.9%, 24/37). There were 26 cases (70.3%, 26/37) of sinus wall osteosclerosis. MRI of paranasal sinus, brain or orbit was performed in 34 cases. T1WI of sphenoid sinus lesions showed low signal, high signal and equal signal in 14, 10 and 9 cases, respectively; T2WI showed high signal, low signal and equal signal in 13, 16 and 2 cases respectively. After enhancement, the lesions were strengthened in 11 cases, no obvious enhancement in 23 cases, and the surrounding mucosa was thickened and strengthened. The lesions involved the orbital apex and cavernous sinus in 18 and 16 cases, respectively; orbital apex and cavernous sinus were involved in 12 cases. Six months after operation, visual acuity was significantly improved in 27 eyes (65.9%, 27/41); visual acuity did not improve in 14 eyes (34.1%, 14/41). Multivariate regression analysis showed that the change of sinus wall osteosclerosis was associated with higher visual acuity improvement rate (odds ratio= 0.089, 95% confidence interval 0.015-0.529, P=0.008). ConclusionsFungal sphenoid sinusitis related visual impairment is relatively common in elderly female patients with low immune function; monocular vision loss with persistent headache is the most common clinical symptom; imaging findings of sphenoid sinus lesions are an important basis for diagnosis. Sphenoid sinus opening combined with sinus lesion clearance is an effective treatment. After operation, the visual acuity of most patients can be improved. The prognosis of visual acuity was relatively good in patients with hyperplasia and sclerosis of sphenoid sinus wall bone.
Objective To investigate the clinical characte ristic of vernier acuity in age-related macular degeneration (AMD) patients. Methods The vernier acuity test soft wear system was developed to detect the 23 cases (39 eyes) of AMD patients. Tweenty-one eyes were atrophic type and 17 eyes were exudative type. Two fixed targets and a movable target are shown on the computer screen. The examinee was asked to adjust the position of the central target and the relationship between it and align them by using a track ball. The computer automatically recorded the deviations of distances between the movable target and the specific one, and then computed and analysed the results of average threshold and variance.Results Both the atrophic and exudative AMD had higher vernier acuity threshold and its variance than normal subjects, and the differences were significant (P＜0.01). The correlation coefficient between visual acuity and vernier acuity threshold was -0.78, and that between visual acuity and threshold variance was -0.80. The results suggest that vernier acuity thre shold and its variance were reliable parameters that reflect the visual acuity in AMD patients.Conclusions The results suggest that vernier acuity threshold and its variance were reliable parameters that reflect the visual acuity in AMD patients.(Chin J Ocul Fundus Dis，2003，19：201-268)
ObjectivesTo evaluate the effects of physical exercises on the vision of students in China.MethodsTrials of the effects of physical exercises on students' vision were retrieved in databases of CNKI, WanFang Data, VIP, Web of Science, EBSCO, PubMed and The Cochrane Library from inception to September 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies. Meta-analysis was carried out with RevMan 5.3 and Stata 13.0 software.ResultsA total of 8 studies including 681 students in the experimental group and 679 in the control group were included. The results of meta-analysis showed that physical exercises were beneficial to improving students' vision (SMD=1.02, 95%CI 0.90 to 1.13, P<0.000 01). The results of subgroup analysis showed that physical exercises in the elementary school students group (SMD=1.361, 95%CI 0.873 to 1.850, P<0.000 01), long period (>24 weeks) (SMD=1.502, 95%CI 0.984 to 2.019, P<0.000 01), medium frequency (3 times/week) (SMD=1.631, 95%CI 1.022 to 2.240, P<0.000 01), and short time (<90 min) (SMD=1.410, 95%CI 0.758 to 2.062, P<0.000 01) had superior results.ConclusionsPhysical exercises have beneficial effects on improving vision. Limited by quantity and quality of subjects, the above conclusions requires verification by more high-quality studies.
ObjectiveTo evaluate the characteristics of electroretinagram (EGR) in children with history of pre-threshold or threshold retinopathy of prematurity (ROP). MethodsA total of 24 children (48 eyes) with history of pre-threshold ROP or threshold ROP received F-ERG examination.Ten age and body weight-matched children with a history of premature birth (20 eyes) but without ROP were recruited as control group. The rod response, maximal rod-cone response and cone response of F-ERG were recorded respectively following the International Standard Protocal of ISCEV (2000 version).The latency and amplitude of a-wave and b-wave of various responses were analyzed. The trial was approved by the Ethic Committee of Hunan Children's Hospital and informed consent was obtained from the parents of patients prior to any medical procedure. ResultsThere was significant difference between ROP and control group in rod response,the latency was longer (t=5.643,P<0.05) and the amplitude was lower in ROP group(t=7.068,P<0.05).In maximal rod-cone response both in a and b wave, the latency wave was longer(t=3.099, 2.886;P<0.05) and the amplitude was lower(t=5.614, 2.850;P<0.05) in ROP group. But there is no difference between ROP and control group in cone response latency(t=0.819, 0.948)and amplitude(t=0.904, 0.850). ConclusionERG in ROP children with history of pre-threshold or threshold ROP is abnormal, which mainly in rod response,but the cone response remains normal.
Objective To observe the clinical features and visual function of recurrent neuromyelitis optica (NMO). Methods Thirty-four patients with NMO were enrolled in this retrospective case series study. The patients included two males and 32 females. The average first onset age was (35.03plusmn;14.56) years old and the average recurrent rate were (4.24plusmn;2.45) times. The recurrent rate of optic neuritis (ON) ranged from two to 12 times. The recurrent rate of ON was two times in 15 eyes of 10 patients, ge;three times in 37 eyes of 24 patients. Vision acuity, direct ophthalmoscope, fundus pre-set lens examination, visual field and visual evoked potential (VEP) were evaluated. Clinical features were observed. The abnormal rate of optic nerve including optic edema and atrophy; abnormal rate of visual field including decreasing retinal sensitivity, central and paracentral scotoma, ring scotoma, half field defects, tunnel visual field, visual field centrality constriction; abnormal rate of VEP including Prolonged latent phase and/or decreasing amplitude of P100 wave from patients of first episode or recurrence was analyzed. Serum NMO-IgG was detected from 28 patients by indirect immunofluorescence technique to observe its positive rate. Results All patients were characterized by repeated episodes of ON and myelitis. The main clinical feature of ON was visual loss, and the main clinical features of myelitis included sensory disability, dyskinesia and vesicorectal disorder. Blindness rate was 41.67% after the first attack of ON, 33.33% after two relapses, and 64.86% after ge; three relapses. The difference of blindness rate between first attack and two episodes was not significant (chi;2=0.270,P=0.603). However, the blindness rate in patients having ge; three episodes was significantly higher than those having two episodes (chi;2=4.300,P=0.038). With recurrence rate increasing, the abnormal rate of the optic nerve (chi;2=6.750,P=0.034）and VEP（chi;2=6.990,P=0.030）increased. But the abnormal rate of visual field did not increase along with recurrent rate (chi;2=0.660,P=0.718). Seropositive rate of NMO-IgG did not differ significantly between patients with first attack ON and that with recurrent ON (chi;2=1.510,P=0.470). But the seropositive patients had significantly higher bilateral blindness rate than seronegative patients (chi;2=5.063,P=0.027). Conclusions NMO are characterized by recurrent ON and myelitis. Visual loss, sensory disability, dyskinesia and vesicorectal disorder are the main clinical features. With recurrence rate increasing, the blindness rate, abnormalities the optic nerve and the abnormity rate of VEP increase. Seropositive recurrent NMO patients have higher bilateral blindness rate than seronegative patients.
Objective To evaluate the causes of the metamorphopsia in patients with reattached retina after scleral buckling surgery. Methods Amsler grid test, ophthalmoscopic examination, fundus fluores cein angiography (FFA) and optical coherence tomography (OCT) were performed on 79 patients (79 eyes) with reattached retina at the 2nd week, 2nd, 6th month and 1st year after scleral buckling operation. Results Two weeks after the operation, 51 patients (51 eyes, 64.56%) complained of metamorphopsia,and 44 patients (44 eyes, including 35 with and 9 without metamorphopsia) were examined by OCT and FFA. In patients with metamorphopsia, the results of OCT in 31 (88.57%) revealed abnormal macula with seven kinds consisting mostly of stratum neuroepithelium detachment (74.29%), while of FFA in 6 patients showed abnormal macular (17.14%) including 4 with neuroepithelium detachment (66.67%). In patients without metamorphopsia, abnormal macula could be found in 2 by OCT while nothing special was seen in FFA. Most abnormal macula in patients followed-up 2 months, 6 months and 1 year postoperatively meliorated as time went by, with alleviative or disappeared metamorphopsia; while the patients with persistently existing macular membrane had aggravating metamorphopsia. Conclusions Abnormal macula is the main reason for metamorphopsia after scleral buckling surgery. Neuroepithelium detachment and macular membrane are the main causes of metamorphopsia at the early and terminal stage after operation.(Chin J Ocul Fundus Dis，2004，20：94-97)