Baixe aqui a versão em PDF da RBO - Sociedade Brasileira de ...

More documents

Recommendations

Info

ARTIGO ORIGINAL95Corneal topographic changes after 20-gaugepars plana vitrectomy associated withscleral buckling for the treatment ofrhegmatogenous retinal detachmentAlterações topográficas da córnea após vitrectomia viapars plana 20-gauge associada à introflexão escleralpara o tratamento do descolamento de retina regmatogênicoAlexandre Achille Grandinetti 1 , Janaína Dias 2 , Ana Carolina Trautwein 3 , Natasha Iskorostenski 3 , Luciane Moreira 4 ,Ana Tereza Ramos Moreira 4ABSTRACTPurpose:To evaluate the changes in corneal topography after 20-gauge pars plana vitrectomy associated with scleral buckling for therepair of rhegmatogenous retinal detachment. Methods: Twenty-five eyes of 25 patients with rhegmatogenous retinal detachment wereincluded in this study. 20-gauge pars plana vitrectomy associated with scleral buckling was performed in all patients. The cornealtopography of each was measured before surgery and one week, one month, and three months after surgery by computer-assistedvideokeratoscopy.Results: A statistically significant central corneal steepening (average, 0,9 D , p
96Grandinetti AA, Dias J, Trautwein AC, Iskorostenski N, Moreira L, Moreira ATRINTRODUCTIONThe treatment of rhegmatogenous retinal detachments andit complications continue to be one of the most importantindications for vitreoretinal surgery, being a well-knowncause of ocular refractive changes. The use of an encircling bandcreates an indentation of the eye that increases the anteroposterioraxial length and can change the corneal shape (1,2) . A myopicshift or lowering hypermetropia and irregular corneal astigmatismowing to the explants can be found (3) . More recently, withthe advent of small gauge transconjunctival vitrectomy, the effectsof the vitrectomy surgery on the cornea have been comparedwhen using different techniques (4) . Some studies haveevaluated corneal changes after pars plana vitrectomy andscleral buckling surgery, and although some studies found statisticallysignificant corneal shape changes (5,6) , others found no significantchanges (7) .Current techniques of rhegmatogenous retinal detachmentrepair allow most detachments to be repaired successfully. However,even after successful retinal reattachment, postoperativevision may be unsatisfactory for the patient in some cases due tosevere myopia or astigmatism that might persist after surgery (8) .The cornea’s refracting surface is responsible for about twothirds of the refractive power of the eye and plays an importantrole in focusing images on the retina. This function can be definedin terms of corneal shape, regularity, clarity and the refractiveindex (5) , all of which might be susceptible to intraoperativecompromise after vitreoretinal surgery.In this study, we investigated the possible corneal changesafter 20-gauge pars plana vitrectomy (PPV) associated withscleral buckling for the treatment of rhegmatogenous retinaldetachment using computer-assisted videokeratography.METHODSTwenty-five patients with rhegmatogenous retinal detachmentwho underwent 20-gaugePPV combined with scleral bucklingwere prospectively included in this study. Approval from theappropriate ethics committee was obtained, and informed consentwas acquired from all patients before surgery.Patients with a history of corneal changes prior to surgery (rigidcontact lens use, refractive surgery, cataract surgery, corneal trauma,corneal transplant, keratoconus, corneal ulcers) and other causes ofretinal detachment (proliferative diabetic retinopathy, tractional, traumatic,associated with tumors of the choroid, and inflammation, amongothers) were excluded from the study. All surgeries were plannedand performed by the same surgeon successfully (AAG).All patients underwent a 20-gauge PPV combined withscleral buckling, which consisted on the placement of a infusioncannula 4 mm from the corneal limbus in the inferior temporalquadrant between the insertions of the rectus muscles, and twosclerotomies 4mm from the corneal limbus in the upper quadrants,always located at the top of the line of the rectus muscles insertion.Total vitrectomy was performed, demarcation of the tearswith endodiatermy, drainage of subretinal fluid followed byendolaser photocoagulation around the retinal tears. Scleral bucklingtechnique was performed using a silicone band number 42(Labtician S2971; Labtician Ophthalmic Inc, Canada), which wassutured in the 4 quadrants at a distance of 11 mm from the corneallimbus, using Mersilene 5.0 sutures to hold the band in the middleof the quadrant. After the surgery was performed, the vitreouscavity substitute was chosen according to the discretion of thesurgeon (perfluoropropane gas or silicone oil) and the sclerotomiesand conjunctiva were closed using 7.0 vicryl sutures.Twenty-five eyes of these 25 patients were analyzed usingcomputerized videokeratography (EyeSys 2000; Corneal AnalysisSystem v4.0). Corneal topography was measured before surgery,as well as one week, one month and three months aftersurgery. At least three videokeratographs were recorded fromeach patient, and the data were obtained from the best qualitykeratograph. The analysis of the corneal videokeratographs wasbased on the Holladay Diagnostic Summary (HDS) softwarepackage. The HDS gives four color-coded maps and 15 cornealparameters. The maps include two refractive power maps on standardand auto scales, a profile difference map for determiningthe corneal shape, and a distortion map that provides informationabout the visual performance and optical quality of the cornea.The parameters from the HDS provide information of thecentral 3mm of the cornea. It should be noted that optical distortionsoutside this 3.0mm pupil zone are shown to have little effecton the visual performance except when the pupil is dilated.In this study, steep refractive power, flat refractive power,and total astigmatism parameters from the HDS were used toinvestigate the changes in corneal topography. The steep refractivepower (K2) is the strongest refractive power in the centralcornea, whereas the flat refractive power (K1) is the weakestrefractive power. The difference between these two parametersis defined as the total astigmatism of the cornea.RESULTSOf the twenty-five patients included in this study, 15 (60%)were male and 10 (40%) were female. The left eye was affectedin 14 patients (56%) and the right eye in 11 patients (44%).The mean age ofthe patients admitted to surgeries was54.52 years, the youngest being 28-year-old and the oldest 68-year-old.The assessment of the macula in the preoperative periodwas defined as attached in 6 cases (24%) and detached in 19cases (76%).The vitreous substitute most commonly used wasperfluoropropane gas (C3F8), in 19 patients (72%), and siliconeoil in 7 cases (28%).After surgery, an average of a 0,9 diopter (D) increase incentral corneal steepening, was detected in the first week. Thedifference was statistically significant when compared with preoperativevalues (p
Page 1 and 2: Versão impressavol. 72 - nº 2 - M
Page 3 and 4: 80Revista Brasileira de Oftalmologi
Page 5 and 6: 82108 Efeitos de algumas drogas sob
Page 7 and 8: 84Kara-Junior Ninúmeras vezes ante
Page 9 and 10: 86Ambrósio Júnior Raplicação de
Page 11 and 12: 88Monte FQ, Stadtherr NMINTRODUÇÃ
Page 13 and 14: 90Monte FQ, Stadtherr NMFigura 1AFi
Page 15 and 16: 92Monte FQ, Stadtherr NMtempo (3) .
Page 17: 94Monte FQ, Stadtherr NM11. Höffli
Page 21 and 22: 98Grandinetti AA, Dias J, Trautwein
Page 23 and 24: 100Ambrósio Jr R, Ramos I, Luz A,
Page 25 and 26: 102Ambrósio Jr R, Ramos I, Luz A,
Page 27 and 28: 104Caballero JCS, Centurion VINTROD
Page 29 and 30: 106Caballero JCS, Centurion VDISCUS
Page 31 and 32: ARTIGO ORIGINALEfeitos de algumas d
Page 33 and 34: 110Almodin J, Almodin F, Almodin E,
Page 35 and 36: 112 ARTIGO ORIGINALFluência do las
Page 37 and 38: 114Lucena AR, Andrade NL, Lucena DR
Page 39 and 40: 116RELATO DE CASOAsymptomatic ocula
Page 41 and 42: 118Freitas LGA, Gabriel LAR, Isaac
Page 43 and 44: 120Ticly FG, Lira RPC, Fulco EAM, V
Page 45 and 46: 122RELATO DE CASOAssociation of mac
Page 47 and 48: 124Tavares RLP, Novelli FJ, Nóbreg
Page 49 and 50: 126Marback EF, Freitas MS, Spínola
Page 51 and 52: 128RELATO DE CASONeurofibromatose t
Page 53 and 54: 130Moraes FS, Santos WEM, Salomão
Page 55 and 56: 132 ARTIGO DE REVISÃOAntifúngicos
Page 57 and 58: 134Müller GG, Kara-José N, Castro
Page 65 and 66: 142 ARTIGO DE REVISÃOImportância
Page 67 and 68: 144Rehder JRCL, Paulino LV, Paulino
Page 69 and 70:
146Rehder JRCL, Paulino LV, Paulino
Page 71 and 72:
148Instruções aos autoresA Revist
Page 73:
150RevistaBrasileira deOftalmologia
show all

Baixe aqui a versão em PDF da RBO - Sociedade Brasileira de ...

Create successful ePaper yourself

Delete template?

Save as template?