Objective To establish a rat model of chronic pulmonary infection by inoculating Pseudomonas aeruginosa to Sprague-Dawley(SD) rats.Metods Sixty SD rats were divided into 2 groups,ie.the P.aeruginosa group and the control group. Silicone tube precoated with P.aeruginosa was placed into the main bronchus. For the control group, sterile silicon tube was intubated. Results P ． aeruginosa was detected from lung tissue of rats in infected groups.Bacterial number was higher than 103cfu ／ g 28 days after inoculation.The pathological study showed fibrinous proliferation and granulomas formation in the lungs of infected rats 28 days after inoculation.Microscopy examination showed a inflammation predominantly with lymphocyte infiltration.In control group, no bacterial and pathological changes could be detected. Conclusions The animal model with P.aeruginosa chronic pulmonary infection can be established successfully by silicone tubes precoated with P.aeruginosa intubated into the main bronchus.
Objective To establish and evaluate a hydrocephalus model in dogs. Methods Twelve healthy adult male mongrel dogs (weight, 10-15 kg) were randomly divided into the control group (n=6) and the experimental group (n=6). All the dogs were given CT and neurological examination to exclude congenital ventricular enlargement and neurological abnormity before they received hydrocephalus induction. Surgical procedures included the exposing of the foramen magnum area, the opening of the atlantooccipita anadesma, and the injecting of silicone oil (0.3 ml/kg) into the fourth ventricle through a silicone tube. Normal saline was injected in the control group. The Tarlov neurological fitness assessment and the Evan’s ratio were used to evaluatethe degree of hydrocephalus at 3, 14 and 56 days after operation. Results In the experimental group, the dogs were dull and unsteady in walking,and they drank and ate less. The lateral ventricle began to expand 3 days afteroperation, and then the temple horn of the lateral ventricle and the third ventricle were also affected 14 days after operation. The ventricles were enlarged progressively after operation. The Tarlov scores measured at 3, 14 and 56 days afteroperation had a significant difference at the same time point between the control group(5.83±0.75，6.50±0.55，6.00±0.63) and the experimental group (4.00±0.89，4.83±1.17，4.50±1.05，P＜0.01), but had no significant difference within the same group at different time points (P＞0.05). The Evan’s ratios measured at 3, 14 and 56 days after operation were 0.33±0.04,0.39±006，0.44±0.03，respectively,in the experimental group; and were 0.27±0.06，0.25±0.09, 0.26±0.05,respectively,in the control group. There was a significant difference atthe same time point between the two groups, and at different time points within the experimental group (P＜0.05).Conclusion The dog model of hydrocephalus induced by the injecting of silicone oil into the fourth ventricle has a highsuccess rate, and the model is appropriate for the studies on diagnosis and therapy of hydrocephalus.
Objective To study the curative effects of keloid by operation combined with postoperative β radiation and silicone gel sheeting. Methods From 1996 to 2002, 598 patients with keloid(243 males, 355 females, aging 15-55 years with an average of 28.6 years) were treated by integrated therapy. Their disease courses were from 6 months to 6 years. The keloid area ranged from 1.0 cm×1.5 cm~8.0 cm×15 cm. First, keloid was removed by operation, and then the wounds weresutured directly(group suture) or covered with skin graft(group graft). In groupsuture, the operational sites were managed by β ray radiotherapy 24-48 hours after operation. The total doses of radiation were 12-15 Gy, 5 times 1 week(group suture A) and 10 times 2 weeks (group suture B). Radiotherapy was not taken until stitches were taken out in group graft, and then the same methods were adopted as group suture B. After radiotherapy, silicone gel sheeting was used in 325 cases for 3-6 months. Results All patients were followed up for 12-18 months. (1) The overall efficacy was 91.3% in group suture A(n=196), and 95.8% in group suture B (n=383), respectively. There was significant difference between the two groups(Plt;0.01). (2) Radiotherapy was of no effect in 6 cases of group graft(n=19). (3) Silicone gel sheeting had effectivenessin 185 cases. Silicone gel sheeting had no obvious effect on the overall efficacy, but it could improve the quality of texture and color of skin. Conclusion By use of integrated methods to treat keloid, if the wound can be sutured directly, skin grafting should not be adopted. The results in group suture B are better than those in group suture A; silicone gel sheeting should be used as possible.
OBJECTIVE To search an ideal carrier of transferred keratinocytes for transplantation. METHODS The transferred keratinocytes were seeded on the surfaces of the artificial dermis and the silicone membrane and cultured in vitro for 2 weeks. The growth of the keratinocytes was observed by microscope and scanning electron microscope. RESULTS The keratinocytes implanted on the artificial dermis began to rupture and died after 2 to 3 days. While the keratinocytes adhered well on the surface of silicone membrane with pseudopodia formation after 1 week under scanning electron microscope, and the cells kept normal morphological and proliferative properties 2 weeks later. CONCLUSION The silicone membrane can be applied as an useful carrier for the keratinocytes transplantation.
In order to improve the therapeutic effect of non-neural tissue in bridging the peripheral nerve defect and increase the blood supply of the implant, the silicone tube was chosen to bridge the gap, and the vessel bundle was inserted into the tube. The procedures were performed as following: resected the pseudoneuroma and enveloped the proximal and the distal ends in a silicone tube, and then sutured the epineurium and the tube wall with 7/0 stitch. In patients, eleven cases with fifteen nerves were treated, including seven median nerves, five ulnar nerves and three radial nerves. The lengths of the nerve defects were within 3 cm in 13 nerves and 3 cm-5 cm in 2 nerves. They were followed up from one to five years and the result was excellent (M4S4) in 8 nerves, good (M3S3) in 3 and poor (M1S1) in 2. It was discussed that the indication for the procedure should be included: the nerve defect could not be sutured directly, and the patient would not agree to use his own nerve for graft.
Along with the wide application of silicone gel implants in augmentation mammaplasty, more complications appeared. The author reported 24 cases of complicationssince 1989, including one case of heamtoma, one case of infection, two cases of injury of the sensory nerves to the nipple, four cases of asymmetric breast (as ymmetry in position and size), three cases of deformed appearance, six cases of constracture of the fibrous coating membrane, one case of rupture of prosthesis,one case of sinus formation and three cases of abnormal milk secretion. The causes of the complications and their prevention were discussed.
Objective To observe the effect of pars plana vitrectomy (PPV) with epiretinal membrane peeling (ERMP) and (or) internal limiting membrane peeling (ILMP) and silicone oil tamponade for highly myopic macular hole retinal detachment (MHRD) with posterior staphyloma. Methods Eighty-five highly myopic MHRD patients (85 eyes) were enrolled in this study. All the patients were examined for corrected visual acuity (CVA), slit lamp microscope and preset lens, indirect ophthalmoscope, A/B ultrasound, optical coherence tomography (OCT) and intraocular pressure examination. The average axial length was (29.1plusmn;1.8) mm. There were 24 eyes with diffuse choroid atrophy and 61 eyes with partial choroid atrophy. The CVA was converted into a logarithm of the minimal angle of resolution (logMAR) for statistical analysis. The average logMAR CVA was 1.93plusmn;0.37. All the patients were treated with PPV and triamcinolone acetonide or indocyanine green (ICG) assisted ILMP and (or) ERMP and silicone oil tamponade. TA assisted ERMP was performed in 21 eyes; with ICG assisted ILMP in 56 eyes and TA assisted ILMP in eight eyes. The duration of silicone oil tamponade was (6.2plusmn;1.6) months. CVA, retina and macular hole status and complications were observed postoperatively. Differences between preoperative and postoperative CVA were evaluated by the t test and correlation analysis. Multiple logistic regression analysis was performed to assess the influence of individual preoperative factors on the initial anatomical success. Differences in the macular hole closure rate between eyes with or without macular schisis were evaluated for statistical significance using corrected chi-square. Results The mean logMAR CVA was 1.34plusmn;0.48 after surgery, which significantly improved compared to that before surgery (t=39.38, P＜0.01). The CVA after surgery was independent of axial length (r=0.142, P＞0.05), choroid atrophy (t=0.23, -0.165,P＞0.05) and macular hole closure (t=0.12, -0.005, P＞0.05). The retina reattached in 79 eyes (92.9%) and recurrence of retinal detachment occurred in six eyes (7.1%). Multiple logistic regression analysis indicated that recurrence of retinal detachment was independent of choroid detachment, proliferative vitroretinopathy, axial length, choroid atrophy and ILMP (OR=1.428, 5.039, 0.815, 2.578, 0.432; P＞0.05). Of these 85 eyes, macular hole closed in ten eyes (11.8%), macular hole did not close in 75 eyes (88.2%). There were 24 eyes (28.2%) experienced high intraocular pressure during the first 2 weeks after surgery, all of them were under control with drugs. There were 12 eyes (14.1%) presented with high intraocular pressure before the silicone oil removal, all of them were under control only by silicone oil removal. Conclusion For the treatment of MHRD with posterior staphyloma, PPV combined with ERMP and (or) ILMP and silicone oil tamponade show a high retinal reattachment rate.
Objective To compare the outcome of C3F8 versus silicone oil intraocular tamponade after pars plana vitrectomy (PPV) for the treatment of severe highly myopic macular hole retinal detachment (MHRD). Methods Thirty-two highly myopic MHRD patients (32 eyes) with extreme long axial lengths (ge;29.0 mm), quot;severequot; retina pigment epithelium (RPE) and chorioretinal atrophy, and posterior staphyloma who underwent PPV, were enrolled in this study. The patients were divided into two groups according to different intraocular tamponade agents: C3F8 (group A, 15 eyes) and silicone oil (group B, 17 eyes). The patients with retinal re-detachment after surgery received PPV again. The differences of sex (P=1.000), age (t=0.444, P=0.660), best-corrected visual acuity (t=0.084, P=0.934), diopter (t=0.449, P=0.978), lens state (P=1.000), time of the symptoms (t=0.375, P=0.710) and degree of retinal detachment (chi;2=0.014, P=0.907) between group A and B were not statistically significant. The anatomic reattachment of the retina, macular hole closure, and vision acuity were observed at one week, one, three, six and 12 months after surgery. Results The rates of retinal reattachment and macular hole closure were 60.00% and 13.33 % in group A, 82.35% and 29.41% in group B in the first time of surgery. There was no difference in rates of retinal reattachment and macular hole closure between two groups (P=0.243, 0.402). The rates of retinal reattachment and macular hole closure were 86.67% and 20.00% in group A, 94.12% and 29.41% in group B in the second time of surgery. There was no difference in rates of retinal reattachment and macular hole closure between two groups (P=0.589, 0.691). Twelve months after surgery, the vision acuity improved in five eyes, unchanged in seven eyes , and decreased in three eyes in group A; the vision acuity improved in seven eyes , unchanged in eight eyes , and decreased in two eyes in group B. The differences of vision result was not statistically significant between two groups (chi;2=0.209, P=0.647). Conclusion The rates of retinal reattachment and macular hole closure with silicone oil tamponade was higher than that with C3F8 tamponade in eyes with severe highly myopic MHRD, but the differences are not statistically significant.
Objective To investigate the main causes and risk factors of recurrent retinal detachment (RRD) after silicone oil removal (SOR) in eyes with complex retinal detachment. Methods It was a retrospective case series study. A total of 458 eyes of 455 consecutive patients who underwent pars plana vitrectomy with silicone oil tamponade were recruited in this study. All patients underwent vitrectomy operation. Additionally, they were given heavy water, membrane peeling, retinotomy or partial cutting, intraocular laser photocoagulation or frozen, gas-liquid exchange or direct oil exchange operation accordingly. Ninety-eight eyes with multiple holes, old retinal detachment, hyperplasia and serious traction lesions underwent scleral buckling surgery simultaneously. Intravitreal silicone oil was padded at the end of operation. Cutting, stripping or resection and 360° preventive laser photocoagulation were applied while the epiretinal membrane was found and need treatment during SOR. Holes or suspicious hiatus underwent intraocular laser photocoagulation or cryotherapy during the operation. One week after SOR and during follow-up, the visual acuity, intraocular pressure (IOP), slit lamp microscope, and ophthalmoscope examination were examined with the same technique and methods as preoperation. The eyes were divide into two groups based on the attachment status of retina after SOR, which were reattached group (419 eyes) and redetached group (39 eyes) respectively. The following data were recorded: the age of patients, ocular axial length, logarithm of minimum angle of resolution (logMAR) best corrected visual acuity (BCVA) and IOP before vitrectomy operation and before and after SOR, the number of retinal breaks, the duration of silicone oil filling, the duration of followup, and the related factors during vitrectomy operation and SOR. The relation of age, sex, high myopia, the size and location of holes, aphakic eye, proliferative vitreoretinopathy (PVR) C3 level and above, previous history of failed retinal detachment operation, 360° preventive laser photocoagulation, assistant scleral buckling surgery, SOR via corneal puncture to RRD after SOR were analyzed. Odds ratio (OR) and its 95% confidence interval (CI) were calculated for the age ＜40 years old and gender. High myopia, assistant scleral buckling surgery and SOR via corneal puncture were further analyzed by multiple regression equation. Results After SOR operation, the total average logMAR BCVA was 0.86±0.63. The average logMAR BCVA was 0.82±0.59 and 0.99±0.70 respectively for the reattached and redetached groups, which was not statistically different (F=1.559,P＞0.05). The number of high myopia eyes in the reattached and redetached groups were 116 and 22 eyes, respectively, accounted for 27.7% and 56.4%, and the difference was statistically significant (χ2=13.984,P＜0.01). Three eyes underwent vitrectomy with scleral buckling occured RRD, accounting for 3.1%; while 36 eyes underwent vitrectomy without scleral buckling occured RRD, accounting for 10.0%. The incidence of RRD between them was statistically significant (χ2=4.761,P＜0.05). The incidence of RRD was not retated to the PVR levels before the operation, previous history of failed retinal detachment operation, aphakic eye and preventive laser photocoagulation (OR=1.626, 1.699, 1.986, 0.709; 95%CI:0.836-3.162, 0.832-3.658, 0.921-4.279, 0.268-1.875; P＞0.05) . RRD had a close relation with high myopia and assistant scleral buckling surgery (OR=3.380, 0.284; 95%CI:1.733 -6.595, 0.086-0.944; P＜0.05). The raise of risk derived from SOR via corneal puncture had no statistical significance (OR=2.119; 95%CI: 1.043-4.306; P＞0.05). The incidence of RRD after SOR was 8.5%; of which, 35.9% originated from new breaks and 69.2% were related to new breaks, in contrast, only 5.1% originated from PVR but 51.3% were related to PVR. ConclusionsHigh myopia is an independent prognostic risk factor of RRD after SOR. Combined scleral buckling surgery is a protective factor of RRD after SOR. To the well reattached eyes before SOR, the new breaks seems to be the main cause of RRD, wheras PVR was probably a secondary phenomenon.
Objective To investigate the feasibility of using magnetic resonance imaging (MRI) to measure the visual axis length in silicone oil filled eyeballs. Methods Thirty-two silicone oil-filled eyes of 32 patients were studied. The antesilicone oil spaces (ASS) and retro-silicone oil spaces (RSS) on the visual axis was measured on the cross-sectional T1 weighted images (T1 WI) and T2WI, the length of the visual axis was measured on the fatsuppressed T2WI. The length of the visual axis was the distance from the corneal vertex to the macular fovea, and it was also measured by A-mode ultrasound in sitting position with different ultrasonic velocity. The postoil gap was also measured by A-mode ultrasound in supine position. Results Compared with the signal of the contralateral vitreous body, the silicone oil signal was higher on T1WI images, lower on T2WI images. After fat suppression, the silicone oil signal and chemical shift artifact were reduced. There were different levels of ASS and RSS in the vitreous cavity of all 32 cases, the RSS depth was (2.47plusmn;1.31) mm on average by MRI. However, RSS was detected in only 56.25% (18 cases)eyeballs by A-mode ultrasound. The visual axis length of silicone oil-filled eyes was (23.52plusmn;4.67) mm by MRI, and (20.57plusmn;5.32) mm by A-mode ultrasound in sitting position. The differences between two measurements was statistically significant (t=30.17, P＜0.05). Conclusions In addition to A-mode ultrasound, MRI might be another effective method to detect RSS and ASS, and to measure the axial length of silicone oil-filled eyes.