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Combined Trabeculotomy and Trabeculectomy: Outcome For Eye (2011) 25, 77–83 & 2011 Macmillan Publishers Limited All rights reserved 0950-222X/11 $32.00 www.nature.com/eye 1 2 3 Combined VA Essuman , IZ Braimah , TA Ndanu and CLINICAL STUDY CT Ntim-Amponsah1 trabeculotomy and trabeculectomy: outcome for primary congenital glaucoma in a West African population Abstract Conclusion The overall success for combined trabeculotomy–trabeculectomy in Ghanaian Purpose To evaluate the surgical outcome of children with primary congenital glaucoma combined trabeculotomy–trabeculectomy in was 79%. The probability of success reduced Ghanaian children with primary congenital from more than 66% in the first 9 months glaucoma. postoperatively to below 45% after that. Materials and methods A retrospective case Eye (2011) 25, 77–83; doi:10.1038/eye.2010.156; series involving 19 eyes of 12 consecutive published online 5 November 2010 1Department of Surgery, children with primary congenital glaucoma University of Ghana Medical who had primary trabeculotomy– Keywords: primary congenital glaucoma; School, College of Health Sciences, University of trabeculectomy from 12 August 2004 to 30 June combined trabeculotomy–trabeculectomy; Ghana, Accra, Ghana 2008, at the Korle-Bu Teaching Hospital, intraocular pressure Ghana. Main outcome measures were 2Eye Unit, Department of preoperative and postoperative intraocular Surgery, Korle-Bu Teaching pressures, corneal diameter, corneal clarity, Introduction Hospital, Accra, Ghana bleb characteristics, duration of follow-up, surgical success, and complications. Primary congenital glaucoma (PCG) is a 3University of Ghana Dental Results A total of 19 eyes of 12 patients met hereditary childhood glaucoma resulting from School, College of Health the inclusion criteria. Six of the patients were abnormal development of the filtration angle, Sciences, University of Ghana, Accra, Ghana males. Mean age at diagnosis was 4.4 (range which occurs unassociated with other ocular or 2–8) months. Mean age at surgery was 5.9 1,2 systemic abnormalities. Correspondence: months (range 3–16). Eight (67%) infants Surgical interventions are the main treatment V Essuman, Department of had bilateral disease. Mean duration of for PCG3 and are designed to eliminate the Surgery, University of Ghana follow-up was 13.1 (range 5–38) months. The resistance to aqueous outflow created by Medical School, College of preoperative mean horizontal corneal diameter structural abnormalities in the anterior chamber Health Sciences, University of Ghana, PO Box GP 4236, was 13.4±1.1(range 12–16) mm. Complete 4,5 angle. Goniotomy and trabeculotomy have Korle-Bu, Accra, KB, Ghana. success (intraocular pressure o21 mm Hg) was traditionally been regarded as procedures of E-mail: vadessuman@ obtained in 15 (79%) eyes. The probability of choice for PCG because of high reported success yahoo.com success was 94.4, 83.3, 66.7, 44.4, 38.9, 33.3, and rates. Goniotomy has the advantage of 13.3% at 3, 6, 9, 12, 15, 18, and 21 months, preserving the conjunctiva for future use, but Received: 23 March 2010 respectively (Kaplan–Meier analysis). All eyes requires a clear cornea and may have to be Accepted in revised form: 19 September 2010 had corneal oedema preoperatively. Seventeen 6 repeated more than once. Trabeculotomy is Published online: 5 eyes (90%) had clear cornea at their last technically easier and produces a more November 2010 follow-up. Mean preoperative and postoperative predictable result than goniotomy.9,10 intraocular pressures were 30.3±8.8 and Trabeculotomy has the added advantage of Presented as e-poster at the 18.1±6.8 mm Hg respectively (Po0.001, t-test). being possible in eyes in which visualization is 1st World Congress of Paediatric Ophthalmology Twelve (63%) eyes had well-functioning blebs not possible, but has the disadvantage of and Strabismus in at the last follow-up. One eye (5%) developed damaging the conjunctiva. In developing Barcelona, Spain, seclusio pupillae and cataract postoperatively. countries, majority of the children with September 2009. Trabeculotomy-trabeculectomy outcome for PCG VA Essuman et al 78 congenital glaucoma present with severe disease and same setting for the EUA. Both eyes were examined cloudy cornea precluding goniotomy.7,8,12 Recent reports under anaesthesia but surgery was performed in one eye. have found combined trabeculotomy–trabeculectomy In bilateral cases surgery was performed in the fellow (CTT) to yield superior results in comparison with eye after 1 or 2 week(s). conventional procedures.9–16 The IOP was measured at the initial phase of halothane In Ghana, majority of children with PCG present with inhalation 1–1.5% when the patients were just sedated, severe disease and cloudy cornea. Conventional using Goldmann applanation method (Perkins trabeculectomy has been the surgical method commonly tonometer by Clement Clarke International, Harlow, UK) used for PCG treatment, but anecdotal data show poor in some patients, and in a few patients by indentation outcomes. A modified trabeculectomy has been tried in method using Shio¨tz tonometer when the former was not the past on some children in the same population available. showing initial success rate more than 90% at 1 year The cornea was assessed under high magnification follow-up (FUP),17 but poor FUP and the small numbers using handheld slit lamp (Zeiss HSO 10 Hand slit lamp studied rendered this procedure of little hope and and ophthalmoscope illuminator H, Carl Zeiss Meditec inconclusive for better outcome. A primary surgical AG, Jena, Germany) in the office setting or with a procedure that yields higher long-term success rate will torchlight and a 20 D lens in theatre before induction of therefore be of great benefit to these children. To the best of anaesthesia. Corneal clarity was assessed based on the our knowledge, there are no published reports on the following criteria: success of CTT from the West African subregion to review. Grade 1: iris texture and pupil seen clearly The purpose of this study was to determine the Grade 2: iris texture and pupil seen hazily surgical outcome of CTT for PCG in Ghanaian children. Grade 3: iris and pupil seen, texture not visible clearly Grade 4: iris and pupil seen very hazily Grade 5: iris and pupil not seen. Materials and methods Horizontal corneal diameter (white to white) was The medical records of all children who had CTT as a measured using callipers. Assessment of the rest of the primary procedure from 12 August 2004 to 30 June 2008 eyes including anterior segment and fundoscopy was were retrieved. As an institutional practice, all clinical and carried out when cornea was clear enough to allow this. surgical notes of all children are routinely recorded on pre- Visual acuity could not be checked in most of the designed forms at the time of diagnosis, during FUP children preoperatively because of photophobia and evaluation and surgery for every child. All surgeries were some aged less than 3 months. Postoperative visual performed by a single surgeon. A total of 32 glaucoma acuity was checked where possible using fixation surgeries were performed and 24 of these were CTT. Patients methods or Cardiff cards. with o3 months FUP were excluded from the study. Data were compiled using pre-designed forms on: age at onset of symptoms (months), age at presentation Surgical procedure (months), age at which surgery was performed (months), Surgery was performed by one surgeon (EVA). Under gender, preoperative visual acuity, postoperative visual general anaesthesia and aseptic technique, superior acuity at the last visit, horizontal corneal diameter (mm), rectus bridal suture or corneal stay suture was placed corneal clarity at presentation, corneal clarity at the last using 4–0 or 6–0 silk. A limbus- or fornix-based FUP, preoperative intraocular pressure (IOP; mm Hg), conjunctival flap was raised and haemostasis was IOP at the last FUP (mm Hg), preoperative optic disc secured with cautery. A 4 Â 4 mm partial thickness scleral vertical cup/disc ratio (VC/D), postoperative VC/D at flap was dissected into about 1 mm of clear cornea. the last FUP, preoperative medications used, A2Â 2 mm inner trabeculectomy groove was carried out. postoperative medications used, complications, A radial incision was then carried out across the inner refractive errors, and duration of FUP. trabeculectomy site about 2 mm from the limbus or the junction between white and bluish transitional zone Examinations of the sclera (this marks externally the site of the Initial examination of all children was performed in the Schlemm’s canal), until the Schlemm’s canal was entered; office setting to make a provisional diagnosis of evidenced by a gush of aqueous humour and/or blood. congenital glaucoma. Diagnosis was confirmed under Trabeculotomy ab externo was then performed using general anaesthesia using 1–1.5% halothane. The Child’s the internal arm of Harm’s trabeculotome probes, first condition was explained to parents and consent was to the left then to the right to complete about 100–1201 obtained for the examination under general anaesthesia of the circumference. The pre-marked 2 Â 2 mm inner (EUA) and for the surgery that was performed at the block tissue comprising trabecular meshwork and scleral Eye Trabeculotomy-trabeculectomy outcome for PCG VA Essuman et al 79 spur was excised with Vannas scissors and peripheral age at diagnosis was 4.4 months (range, 2–8; median, iridectomy was performed with a base of at least 2 mm. 4.0 months). The mean age at surgery was 5.9 months The partial thickness scleral flap was sutured using three (range, 3–16 months; median, 4.0 months). Eight (67%) interrupted sutures (at apex and the two sides) with 10–0 of the infants had bilateral disease. nylon. The conjunctival flap was closed with 8–0 or 6–0 vicryl (polyglactin) continuous stitches. At the end of the Intraocular pressure surgery, the patency of the peripheral iridectomy and scleral flap and how watertight the conjuctival flap were The mean preoperative IOP was 30.3 mm Hg (range, assessed.
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