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1.
Retina ; 42(2): 306-312, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35050929

RESUMO

PURPOSE: To report the long-term outcomes of lens capsular flap transplantation (LCFT) as initial treatment for large macular holes (MHs). METHODS: Thirteen consecutive eyes with large MHs who received LCFT as primary treatment were reviewed retrospectively. All enrolled eyes underwent standard 23-gauge vitrectomy, internal limiting membrane peeling, LCFT, and 15% perfluoropropane tamponade. Autologous whole blood was applied in selected eyes to make the LCT intact. A face-down position maintained for 2 weeks postoperatively. Data including demographic information, medical history, anatomical and functional outcomes, and complications were recorded. RESULTS: The mean preoperative MHs diameter was 979.42 ± 388.28 µm. Eight eyes received autologous LCFT, and the other five eyes received allogenic LCFT. Whole blood was applied in seven eyes. The mean follow-up duration was 19.57 ± 6.24 months (range: 12.0-32.2 months). The macular hole was successfully closed in all cases (13/13). The median best-corrected visual acuity improved from 1.76 (interquartile range, 1.23-1.91) logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,150) preoperatively to 1.16 ± 0.47 logarithm of the minimum angle of resolution (mean Snellen acuity: 20/290) (P < 0.01) at the last visit. No severe complications were noted. CONCLUSION: Lens capsular flap transplantation may help to improve the closure rate and visual outcomes in large MHs, which could be an alternative method as primary treatment for large MHs.


Assuntos
Tamponamento Interno , Cápsula do Cristalino/transplante , Perfurações Retinianas/cirurgia , Retalhos Cirúrgicos/transplante , Vitrectomia , Idoso , Extração de Catarata , Criança , Feminino , Fluorocarbonos/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Decúbito Ventral , Perfurações Retinianas/diagnóstico por imagem , Perfurações Retinianas/fisiopatologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Transplante Autólogo , Resultado do Tratamento , Acuidade Visual/fisiologia
2.
Retina ; 41(4): 726-734, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32732611

RESUMO

PURPOSE: To report long-term surgical outcomes of autologous and allogenic lens capsular flap transplantation (LCFT) in refractory macular hole (MH) treatment. METHODS: Fifty consecutive eyes with refractory MH who received LCFT were reviewed retrospectively. Twelve eyes underwent autologous LCFT (LCF obtained from the same eye in 7 eyes and the fellow eye in 5 eyes) and 38 eyes with allogenic LCFT. All eyes underwent complete vitrectomy, internal limiting membrane peeling if not peeled, LCF transplantation, and 15% perfluoropropane tamponade. Simultaneous autologus whole-blood application was applied in 31 eyes to reduce LCF dislocation. The patients maintained a facedown position for 2 weeks postoperatively. Demographic information, functional results, and structural changes were evaluated. RESULTS: The mean preoperative MH diameter was 1,102.00 µm ± 561.63 µm. The mean follow-up duration was 18.50 months ± 6.05 months (range, 12.0-38.9 months). The MH was completely closed in 48 eyes (96.00%) (18 eyes receiving autologous LCFT and 30 receiving allogenic LCFT). There are no differences of age, previous MH surgery times, MH diameter, preoperative and postoperative best-corrected visual acuity, and closure rate between the subgroups. The median visual acuity improved from 1.78 (interquartile range, 1.28-1.85) logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,200) preoperatively to 1.00 (interquartile range, 0.90-1.70) logarithm of the minimum angle of resolution (median Snellen acuity: 20/200) (P < 0.01) in all patients. CONCLUSION: Both autologous and allogenic LCFT application may provide anatomical and visual improvements in refractory MH cases. Blood application can be applied in selected cases to reduce LCF dislocation. LCFT can be performed as first-line treatment for refractory MHs.


Assuntos
Cápsula do Cristalino/transplante , Perfurações Retinianas/cirurgia , Adulto , Idoso , Membrana Basal/cirurgia , Fenômenos Fisiológicos Sanguíneos , Tamponamento Interno , Feminino , Fluorocarbonos/administração & dosagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Perfurações Retinianas/fisiopatologia , Estudos Retrospectivos , Tomografia de Coerência Óptica , Transplante Autólogo , Transplante Homólogo , Resultado do Tratamento , Acuidade Visual/fisiologia , Vitrectomia
3.
Ophthalmic Surg Lasers Imaging Retina ; 50(10): 649-652, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31671198

RESUMO

A patient with acquired optic disc pit (ODP) maculopathy underwent vitrectomy with anterior capsule transplantation to the ODP and gas tamponade. Structural changes were evaluated by enhanced depth imaging optical coherence (OCT) tomography. During vitrectomy, the eye was confirmed to have preexisting posterior vitreous detachment. Postoperative OCT showed complete closure of the optic pit resulting in rapid absorption of subretinal fluid. The authors' observations suggest that the anterior capsule is a useful material for achieving optic pit closure. To the authors' knowledge, this is the first report describing application of the anterior capsule to the treatment of ODP maculopathy. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:649-652.].


Assuntos
Cápsula do Cristalino/transplante , Disco Óptico/cirurgia , Doenças do Nervo Óptico/cirurgia , Doenças Retinianas/cirurgia , Vitrectomia/métodos , Idoso , Feminino , Humanos , Estudos Retrospectivos
4.
Ophthalmic Surg Lasers Imaging Retina ; 49(11): 901-903, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30457651

RESUMO

The authors report a case of a retinal detachment secondary to multiple eccentric macular holes (MEMHs) following an uneventful pars plana vitrectomy and epiretinal membrane peel, successfully treated by autologous lens capsule graft. Anatomical and functional changes were also evaluated. Autologous lens capsule graft is a safe and effective treatment for MEMHs that may improve anatomical and functional results. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:901-903.].


Assuntos
Cápsula do Cristalino/transplante , Descolamento Retiniano/cirurgia , Perfurações Retinianas/complicações , Retalhos Cirúrgicos , Acuidade Visual , Vitrectomia/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/etiologia , Perfurações Retinianas/diagnóstico , Perfurações Retinianas/cirurgia , Tomografia de Coerência Óptica , Transplante Autólogo
5.
Retin Cases Brief Rep ; 12(4): 286-290, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28033231

RESUMO

PURPOSE: To report the use of anterior lens capsule flap transplantation in two cases with chronic full-thickness macular hole (MH). METHODS: Case series. RESULTS: Two cases of chronic MH with a new treatment approach were reported. In the first case, a 66-year-old man presented with a chronic idiopathic MH in the left eye for 2 years. Presenting visual acuity was hand motion. The patient underwent phacoemulsification and vitrectomy with anterior lens capsule flap transplantation in the MH. At 5 months postoperatively, the visual acuity was 20/200 with MH closure. In the second case, a 68-year-old woman presented with decreased visual acuity for 2 years. Her visual acuity was hand motion in the right eye. The patient underwent phacoemulsification and vitrectomy with anterior lens capsule flap transplantation in the MH. Visual acuity improved to 20/400 with reduction in the MH diameter. Vision and MH diameter remained stable over 5 months postoperatively. CONCLUSION: Lens capsular flap transplantation is useful in closing chronic MH in the short term.


Assuntos
Cápsula do Cristalino/transplante , Facoemulsificação/métodos , Perfurações Retinianas/cirurgia , Vitrectomia/métodos , Idoso , Segmento Anterior do Olho/cirurgia , Doença Crônica , Feminino , Humanos , Retalhos Cirúrgicos , Resultado do Tratamento
6.
Retina ; 38(11): 2177-2183, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29045320

RESUMO

PURPOSE: To report results of lens capsular flap transplantation (LCFT) and autologous whole blood application in refractory macular hole (MH) treatment. METHODS: Seven phakic and three aphakic eyes with persistent MH after standard surgery with internal limiting membrane peeling were studied. Lens capsule flap was acquired from the same eye in eight cases (seven phakic and one aphakic). The fellow eye was used in two aphakic eyes without sufficient lens capsule. The fellow eye underwent simultaneous phacoemulsification. All eyes underwent complete vitrectomy, LCFT into the MH, whole blood application, and 15% perfluoropropane (C3F8) tamponade. The patients were instructed to maintain a face-down or prone position for two weeks postoperatively. Structural and functional changes were evaluated. RESULTS: The mean preoperative MH diameter was 1,472.78 ± 736.88 µm. The MH was completely closed in nine eyes: eight eyes receiving same-eye LCFT and one receiving fellow-eye LCFT. In the other fellow-eye LCFT recipient, the MH was partially closed. Visual acuity improved from 1.84 ± 0.49 logarithm of the minimum angle of resolution (median Snellen acuity: 20/1,750, range: 20/4,000-20/125) preoperatively to 1.34 ± 0.59 logarithm of the minimum angle of resolution (median Snellen acuity: 20/450, range: 20/4,000-20/63) postoperatively (P = 0.009). CONCLUSION: Lens capsular flap transplantation and autologous whole blood application may improve anatomical and visual outcomes in refractory MH cases. The lens equator and fellow eye may be promising sources of LCF.


Assuntos
Transfusão de Sangue Autóloga/métodos , Cápsula do Cristalino/transplante , Perfurações Retinianas/cirurgia , Retalhos Cirúrgicos , Acuidade Visual , Vitrectomia/métodos , Adulto , Idoso , Tamponamento Interno , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Retina/diagnóstico por imagem , Perfurações Retinianas/diagnóstico , Estudos Retrospectivos , Tomografia de Coerência Óptica , Transplante Autólogo , Resultado do Tratamento
7.
Semin Ophthalmol ; 33(2): 143-148, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27533623

RESUMO

PURPOSE: To evaluate the efficacy of autologous anterior lens capsule (ALC) in phacotrabeculectomy. MATERIAL AND METHODS: In this prospective, randomized case control study, after obtaining institutional ethical clearance and informed consent, 88 eyes posted for phacotrabeculectomy were divided into ALC and non-ALC groups. Combined phacoemulsification, with posterior chamber intraocular lens implantation and trabeculectomy, was performed in both groups. Anterior lens capsule transplantation was done in the first group beneath the sclera flap. Follow-up of three months was carried out and the morphology of bleb, intraocular pressure (IOP), requirement for additional medications, and complications were compared between the two groups. RESULT: Statistical difference favoring the ALC group was seen in IOP reduction (p < 0.05) at each follow-up, qualified success rate and failure rate at the three-month follow-up (p = 0.006), but no difference in bleb morphology was seen. CONCLUSION: ALC implantation is beneficial in maintaining filtration in a combined surgery with minimal complications.


Assuntos
Catarata/complicações , Glaucoma de Ângulo Aberto/cirurgia , Cápsula do Cristalino/transplante , Facoemulsificação/métodos , Esclera/cirurgia , Retalhos Cirúrgicos , Trabeculectomia/métodos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante Autólogo , Resultado do Tratamento , Acuidade Visual
8.
Retina ; 36(1): 163-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26200509

RESUMO

PURPOSE: To report the clinical results of lens capsular flap transplantation in refractory macular hole (MH). METHODS: This retrospective, interventional, consecutive case series included 20 eyes with persistent MH after previous standard MH surgery. All eyes underwent vitrectomy, lens anterior or posterior capsule transplantation into the MH, gas tamponade, and a 1-week postoperative head down. Structural and functional changes were evaluated. RESULTS: The predisposing conditions to surgical failure included high myopia with MH and retinal detachment in four eyes, MH after myopic foveoschisis surgery in one eye, high myopia with a large MH in one eye, proliferative diabetic retinopathy with MH in three eyes, MH with severe retinal detachment in one eye, retinal detachment with concurrent peripheral breaks and MH in one eye, and large or chronic MH in nine eyes. Macular hole was closed in all the 10 eyes receiving anterior capsular flap transplantation. In the 10 eyes with posterior capsular flap transplantation, MH was closed in 5, partially closed in 3, and not closed in 2. Visual acuity in logarithm of minimal angle of resolution improved from 1.53 ± 0.39 preoperatively to 1.07 ± 0.35 postoperatively. CONCLUSION: Lens capsular flap transplantation may close the MH and improve visual outcome in the majority cases of refractory MH.


Assuntos
Tamponamento Interno , Cápsula do Cristalino/transplante , Perfurações Retinianas/cirurgia , Retalhos Cirúrgicos , Vitrectomia , Idoso , Feminino , Fluorocarbonos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Miopia Degenerativa/complicações , Decúbito Ventral , Descolamento Retiniano/complicações , Perfurações Retinianas/etiologia , Perfurações Retinianas/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Hexafluoreto de Enxofre/administração & dosagem , Acuidade Visual/fisiologia
10.
J Glaucoma ; 20(8): 514-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20717048

RESUMO

AIM: Efficacy of using the anterior lens capsule removed during combined phacotrabeculectomy as an adjunct to trabeculectomy and comparing it to Mitomycin-C. METHODS: Prospective randomized study. Two site phacotrabeculectomy and at the end of the surgery, the removed anterior lens was placed under the scleral flap in group I and Mitomycin C in group II. RESULTS: No significant difference between the intraocular pressure, antiglaucoma medications, or visual acuity. No complications were related to anterior lens capsule. CONCLUSIONS: Anterior lens capsule is effective in phacotrabeculectomies.


Assuntos
Alquilantes/administração & dosagem , Glaucoma/cirurgia , Cápsula do Cristalino/transplante , Mitomicina/administração & dosagem , Facoemulsificação , Trabeculectomia , Idoso , Catarata/complicações , Catarata/terapia , Feminino , Glaucoma/complicações , Humanos , Pressão Intraocular/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Retalhos Cirúrgicos , Técnicas de Sutura , Tonometria Ocular , Acuidade Visual/fisiologia
11.
Ophthalmic Surg Lasers Imaging ; 39(3): 260-1, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18556957

RESUMO

A new method is presented for the closure of the lens capsule based on laser welding of suitably prepared patches of anterior capsular tissue. Experiments were performed in freshly enucleated porcine eyes. The patches were previously stained with a solution of indocyanine green in sterile water and then welded on the recipient capsule by means of diode laser radiation at 810 nm. The welded tissue revealed mechanical properties comparable to those of healthy tissue. This technique is proposed to repair capsular breaks and to provide the closure of the capsulorhexis in lens refilling procedures.


Assuntos
Capsulorrexe/métodos , Lasers Semicondutores , Cápsula do Cristalino/cirurgia , Cápsula do Cristalino/transplante , Animais , Implante de Lente Intraocular , Suínos
12.
Biomaterials ; 27(8): 1670-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16199085

RESUMO

We have investigated human anterior lens capsule as a potential replacement for Bruch's membrane as a treatment for age-related macular degeneration. Any substrate to replace Bruch's membrane should possess certain characteristics to maintain proper function of the overlying retina. One of the important properties of Bruch's membrane is allowing the flow of nutrients and waste between the retinal pigment epithelium and the choriocapillaris. Here, we measured the permeability of the lens capsule by studying the diffusion of various molecular weight FITC-dextran molecules. Expressions for extraction of diffusion coefficients from concentration vs. time data from a blind-well chamber apparatus were derived for both a single and double membrane experiments. The diffusion coefficients in the lens capsule were found to be in the range of 10(-6) to 10(-10)cm2/s. We demonstrated a power law relationship, with the diffusion coefficient possessing a -0.6 order dependence on molecular weight. The molecular weight exclusion limit was determined to be 150+/-40 kDa. We have compared this value with reported values of Bruch's membrane molecular weight exclusion limit and find that the lens capsule has the potential to act as a substitute Bruch's membrane.


Assuntos
Lâmina Basilar da Corioide/cirurgia , Cápsula do Cristalino/metabolismo , Cápsula do Cristalino/transplante , Degeneração Macular/cirurgia , Dextranos/metabolismo , Difusão , Estudos de Viabilidade , Humanos , Peso Molecular , Permeabilidade , Soluções
13.
Cornea ; 23(8): 797-803, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15502481

RESUMO

PURPOSE: This study provides ultrastructural morphology and quantitative analysis of allotransplants of anterior lens capsule in the treatment of recurrent corneal ulcers. METHODS: Mechanical ulcers of uniform size were created with a 6-mm corneal trephine in 9 eyes at one-third corneal depth in 6 white New Zealand male rabbits. Following initial epithelial regrowth, an identical injury was created in the same area of each cornea a second time. In 6 eyes (treated group), an anterior lens capsule from a healthy donor rabbit was sutured into the ulcer bed, followed by antibiotic/steroid drops 3 times daily for 1 week. The remaining 3 control eyes were allowed to heal without surgical intervention using the same antibiotic/steroid drops only. Slit-lamp examination, histopathology, and electron microscopic findings with hemidesmosome counts and size were recorded over a 3-month follow-up period. RESULTS: The control injured group had discontinuous epithelial basement membrane with significant reduction in hemidesmosome count compared with noninjured controls (P<0.0001). The treated subgroup 7 days after surgery showed linear basement membrane with identifiable lamina lucida and densa and newly-formed hemidesmosomes, which were significantly more numerous than in the injured but nontreated group (P<0.0001). Numerous hemidesmosomes and firm adhesion of epithelium to underlying stroma were seen in this group with lens capsule allografts 3 months after surgery. The number and size of hemidesmosomes did not significantly differ between groups 7 days and 3 months after surgery. CONCLUSIONS: On the ultrastructural level, anterior lens capsule allotransplants in mechanically induced corneal ulcer heal with continuously formed epithelial basement membrane and numerous hemidesmosomes. This enables significant reformation of hemidesmosomes that are identical in size to hemidesmosomes in healthy corneas and helps forming a stronger apposition for epithelial cells to underlying structures in eyes where epithelial basement membrane has been destroyed from chronic ulceration.


Assuntos
Úlcera da Córnea/cirurgia , Cápsula do Cristalino/transplante , Cápsula do Cristalino/ultraestrutura , Animais , Segmento Anterior do Olho , Membrana Basal/ultraestrutura , Adesão Celular/fisiologia , Doença Crônica , Úlcera da Córnea/patologia , Modelos Animais de Doenças , Epitélio Corneano/ultraestrutura , Hemidesmossomos/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão , Coelhos , Recidiva , Técnicas de Sutura , Transplante Homólogo , Cicatrização
14.
Cesk Slov Oftalmol ; 60(4): 261-6, 2004 Jul.
Artigo em Eslovaco | MEDLINE | ID: mdl-15369262

RESUMO

This study uses immunofluorescent analysis to find out in histologic corneal sections a possible rejection reaction in anterior lens capsule allotransplantation for chronic corneal ulcers. The experiment included control group of rabbit corneas with repeat injury to epithelium and anterior stroma as well as surgically treated group. Fluorescein-conjugated human antibodies to IgA, IgM, IgG, complement and fibrinogen were used in the study. For detection we used method of direct immunofluorescence. Positive was only examination on fibrinogen in sections of treated group eyes 2 days after surgery. Last examination after 3 months failed to detect positivity in any of the tested markers. We preliminarily conclude that anterior lens capsule allotransplantation for chronic corneal ulcers does not result in rejection reaction and that components of humoral immunity do not participate in immune reaction.


Assuntos
Úlcera da Córnea/cirurgia , Cápsula do Cristalino/imunologia , Cápsula do Cristalino/transplante , Animais , Doença Crônica , Complemento C3/análise , Técnica Direta de Fluorescência para Anticorpo , Imunoglobulinas/análise , Coelhos , Transplante Homólogo
15.
Cornea ; 22(4): 359-62, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12792481

RESUMO

PURPOSE: This study was designed to measure the value of allografted anterior lens capsule in the reepithelialization of recurrent corneal ulcers. METHODS: Mechanical ulcers of uniform size were created with a 6-mm corneal trephine in both eyes of four Chinchilla male rabbits at one-third corneal depth. Following initial epithelial regrowth, an identical injury was created in the same area of each cornea a second time. In four eyes (treated group), an anterior lens capsule from a healthy donor rabbit was sutured into the ulcer bed followed by antibiotic/steroid drops three times daily for 1 week. The remaining four control eyes were allowed to heal without surgical intervention using the same antibiotic/steroid drops only. Slit-lamp examination and histopathology findings were recorded over a 6-month follow-up period. RESULTS: The four treated eyes reepithelialized after the second injury at a faster rate than the control group eyes and had a lower percentage of corneal opacification at all follow-up exam dates. Histopathology revealed normal epithelium overlying the transplanted anterior lens capsule and no infiltration of inflammatory cells in the subepithelial stroma. CONCLUSIONS: In experimental conditions, allotransplantation of anterior lens capsule speeds up reepithelialization after repeated mechanical trauma to the cornea. To our knowledge, this is the first experimental transplantation of an anterior lens capsule to create an artificial Bowman's layer in recurrent corneal ulcerations to aid reepithelialization and minimize corneal scarring.


Assuntos
Córnea/cirurgia , Úlcera da Córnea/cirurgia , Cápsula do Cristalino/transplante , Animais , Chinchila , Doença Crônica , Córnea/patologia , Córnea/fisiopatologia , Úlcera da Córnea/patologia , Úlcera da Córnea/fisiopatologia , Epitélio Corneano/fisiopatologia , Masculino , Coelhos , Recidiva , Transplante Homólogo
16.
Acta Ophthalmol Scand ; 80(1): 76-81, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11906309

RESUMO

PURPOSE: To investigate the consequences of transplantation of a new basement membrane to the subretinal space (SRS) as a substitution of Bruch's membrane. METHODS: Porcine anterior lens capsules (ALC) were transplanted to the subretinal space of 20 eyes from 19 young Danish landrace pigs. All pigs underwent a three port localized pars plana vitrectomy. Seventeen eyes received naked ALC. In three experiments the ALC was embedded in gelatine, in order to prevent curling of the ALC. The observation period varied between zero and 49 days. The pigs were examined by ophthalmoscopy and fundus photography. Histopathological examination of enucleated eyes was performed at the end of the experiment. RESULTS: ALCs transplanted to the subretinal space were well-tolerated and caused no inflammation when Bruch's membrane was left undamaged. After 11 days host RPE and glial cells started to cover the ALC in a competitive fashion. When Bruch's membrane was damaged, ingrowths of choroidal vessels and fibroblasts was prominent. The use of gelatine to flatten the ALC did not prevent curling, and gelatine caused pronounced inflammation. CONCLUSIONS: It is possible to transplant porcine ALC to the SRS of the pig. ALCs are well-tolerated in the SRS and are covered with well-differentiated monolayers of host RPE-cells, if Bruch's membrane is left intact.


Assuntos
Cápsula do Cristalino/transplante , Retina/cirurgia , Animais , Segmento Anterior do Olho , Espaço Extracelular , Cápsula do Cristalino/patologia , Neuroglia/fisiologia , Oftalmoscopia , Fotografação , Epitélio Pigmentado Ocular/citologia , Retina/patologia , Suínos , Transplante Homólogo , Vitrectomia
17.
Cell Transplant ; 9(6): 759-72, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11202563

RESUMO

We have developed a new type of polymer/cell/matrix implant and tested whether it can promote the regrowth of retinal ganglion cell (RGC) and other axons across surgically induced tissue defects in the CNS. The constructs, which consisted of 2-2.5-mm-long polycarbonate tubes filled with lens capsule-derived extracellular matrix coated with cultured neonatal Schwann cells, were implanted into lesion cavities made in the left optic tract (OT) of 18-21-day-old rats. In one group, to promote Schwann cell proliferation and perhaps also to stimulate axon regrowth, basic fibroblast growth factor (bFGF) was added to the lens capsule matrix prior to implantation. In another group, to determine whether application of growth factors to the somata of cells enhances the regrowth of distally injured axons, the neurotrophin NT-4/5 was injected into the eye contralateral to the OT lesion. NT-4/5 and bFGF treatments were combined in some rats. After medium-term (4-10 weeks) or long-term (15-20 weeks) survivals, axon growth into implants was assessed immunohistochemically using a neurofilament (RT97) antibody. RGC axons were visualized after injection of WGA/HRP into the right eye. Viable Schwann cells were present in implants at all times after transplantation. Large numbers of RT97+ axons were consistently found within the bridging implants, often associated with the peripheral glia. Axons were traced up to 1.7 mm from the nearest CNS neuropil and there was immunohistochemical evidence of myelination by Schwann cells and by host oligodendrocytes. There were fewer RGC axons in the implants, fibers growing up to 1.6 mm from the thalamus. Neither NT-4/5 nor bFGF, alone or in combination, significantly increased the extent of RGC axon growth within the implants. A group of OT-lesioned rats was implanted with polymer tubes filled with 2-2.5-mm-long pieces of predegenerate peripheral nerve. Surprisingly, polymer/cell/matrix constructs contained comparatively greater numbers of RGC and other axons and supported more extensive axon elongation. Thus, implants of this type may potentially be useful in bridging large tissue defects in the CNS.


Assuntos
Axônios/fisiologia , Transplante de Células/métodos , Cápsula do Cristalino/transplante , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/cirurgia , Células Ganglionares da Retina/ultraestrutura , Células de Schwann/transplante , Animais , Astrócitos/química , Astrócitos/citologia , Biopolímeros , Células Cultivadas , Matriz Extracelular , Fator 2 de Crescimento de Fibroblastos/farmacologia , Proteína Glial Fibrilar Ácida/análise , Imuno-Histoquímica , Cápsula do Cristalino/citologia , Teste de Materiais , Compressão Nervosa , Fatores de Crescimento Neural/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oligodendroglia/fisiologia , Ratos , Ratos Endogâmicos , Proteínas S100/análise , Células de Schwann/citologia , Nervo Isquiático/citologia , Nervo Isquiático/cirurgia , Conjugado Aglutinina do Germe de Trigo-Peroxidase do Rábano Silvestre
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