Clinical outcomes and significance of postoperative ultrasound biomicroscopy in patients with Boston type 1 keratoprosthesis.

PURPOSE: To determine the clinical outcomes in patients after type 1 Boston keratoprosthesis surgery and the significance of ultrasound biomicroscopy imaging for postoperative follow-up. METHODS: This retrospective analysis included 20 eyes of 19 patients who underwent corneal transplantation with type 1 Boston keratoprosthesis between April 2014 and December 2021. Data on patient demographics, preoperative diagnosis, visual acuity, and postoperative clinical findings were analyzed. RESULTS: Type 1 Boston keratoprosthesis implantation resulted in intermediate- and long-term positive outcomes. However, blindness and other serious complications such as glaucoma, retroprosthetic membrane formation, endophthalmitis, or retinal detachment also occurred. The use of ultrasound biomicroscopy imaging allowed for better evaluation of the back of the titanium plate, anterior segment structures, and the relationship of the prosthesis with surrounding tissues, which provided valuable postoperative information. CONCLUSION: Regular lifetime monitoring and treatment are necessary in patients who undergo Boston type 1 keratoprosthesis implantation for high-risk corneal transplantation. ultrasound biomicroscopy imaging can be a valuable imaging technique for the evaluation of patients with Boston type 1 keratoprosthesis, providing important information on anterior segment anatomy and potential complications. Further studies and consensus on postoperative follow-up protocols are required to optimize the management of patients with Boston type 1 keratoprosthesis.

A new technique to implant intracorneal ring-segments from the perilimbal region: one-year prospective pilot study report.

BACKGROUND: Recently a new surgical technique for intracorneal ring-segments (ICRS) assisted by femtosecond laser (FSL) called ByLimB was developed, involving the creation of the incision from a paralimbic region. This study aims to evaluate the safety and efficacy of the ByLimb technique following one year of follow-up. METHODS: A prospective, single-center study was conducted at the Zaldivar Institute in Buenos Aires, Argentina. Keratoconus patients with indication for ICRS-FSL assisted procedure, operated with the ByLimb technique were included. By using the ByLimb technique, the ICRS are placed without affecting the tunnel's roof, and the end of the ICRS is always away from the incision area. Visual acuity, topographic astigmatism, and the occurrence of complications were evaluated. Safety index was the main outcome and efficacy indes was a complimentary outcome. RESULTS: A total of 17 eyes completed the 12-month follow-up period. The safety index was 1.10 (mean postoperative corrected distance visual acuity (CDVA) in decimal: 0.76/preoperative CDVA: 0.69), while the efficacy index was 0.89 (mean postoperative uncorrected distance visual acuity UDVA in decimal: 0.62/preoperative CDVA: 0.69). Mean preoperative astigmatism was 5.3 ± 2.3, decreasing twelve months after surgery at 2.1 ± 1.2 (p < 0.001). No eye loss lines of vision and no intraoperative complications were observed. During the first month after surgery, an improper positioning of the ICRS based on topographic assessment was detected in five cases. A second procedure was performed, which consisted of opening the incision and introducing a Sinsky hook, through which the ICRS was mobilized and placed in its correct position. No incisional alterations, signs of infection, anterior segment anomalies, or fundus alterations were observed. CONCLUSION: FSL-assisted ICRS implantation through the perilimbal region has demonstrated an adequate safety index one year post-surgery. Additionally, this technique has facilitated accurate realignment of ICRS during secondary surgical interventions within one-month post-surgery. While the current findings are promising, continued follow-up of these cases is warranted.

Cataract surgery and artificial iris implantation in patient with oculocutaneous albinism: a case report.

We present a case report detailing the successful phacoemulsification surgery with artificial iris implantation for two individuals with oculocutaneous albinism. These women suffered from cataracts, resulting in reduced visual acuity and heightened photophobia due to iris pigmentary epithelium deficiency. The patients underwent phacoemulsification along with prosthetic artificial iris implantation into the posterior chamber. This intervention resulted in improved visual acuity, reduced photophobia and glare, and an overall enhanced quality of life. Our report highlights two cases of successful phacoemulsification and artificial iris implantation in patients with oculocutaneous albinism and cataracts, leading to improved visual acuity, reduced photophobia, and enhanced quality of life. Notably, there are no prior records in South American literature of cataract surgery combined with artificial iris implantation for oculocutaneous albinism patients up to the time of this publication.

Glaucoma drainage devices in children: an updated review.

Implantation of glaucoma drainage devices is a valuable therapeutic option, particularly in children with glaucoma refractory to primary surgical treatment. Glaucoma drainage devices are typically used when conjunctival scarring hampers filtration surgery or prior angle procedures are not effective in controlling intraocular pressure. Despite known complications, the use of glaucoma drainage devices in children has increased in recent years, even as the primary surgical option. In this review, we evaluate the results of recent studies involving the implantation of glaucoma drainage devices in children, discussing new advances, and comparing the success rates and complications of different devices.

The Scalloped Surgical Guide as an Alternative to Flat Bone Reduction Guide in Full-Arch Implant Restoration.

The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery.

Complicaciones perianales causadas por agentes modeladores inyectados en glúteos / Perianal complications caused by gluteal injection of modeling agents

En este reporte presentamos tres pacientes en quienes ocurrieron condiciones inflamatorias perianales tardías, luego de la administración de sustancias modeladoras no identificadas en los glúteos. El diagnóstico inicial y supuesto no fue correcto, ya que no se investigó durante la evaluación preliminar el antecedente de la administración de elementos modeladores. Recomendamos que los pacientes con patologías inflamatorias del ano, sobre todo aquellos cuyo curso es extraño, se les pregunte acerca de la administración de agentes modeladores en los glúteos. Esta práctica puede contribuir a la eficacia del diagnóstico de manifestaciones perianales caracterizadas por flogosis, que se presentan de forma inusual. (AU)

In this report we present three patients in which late perianal inflammatory conditions occurred after administration of unidentified modeling agents to the buttocks. The initial diagnosis was not correct because of the administration of modeling agents was not investigated during the initial eval-uation. We recommend inquiring patients with inflammatory pathologies of the anus, especially those whose course is unusual, about the adminis-tration of modeling agents to the buttocks. This approach can contribute to the efficiency of the diagnosis of perianal complaints characterized by inflammation, but rare in its appearance. (AU)

Evaluation of early ocular discomfort after glaucoma surgery: trabeculectomy versus Ahmed glaucoma valve implantation.

PURPOSE: This study aims to compare the initial ocular discomfort symptoms resulting from trabeculectomy and Ahmed glaucoma valve implantation surgeries. METHODS: A prospective comparative study was conducted. The evaluation of ocular discomfort employed a questionnaire designed to identify the frequency and severity of distinct symptoms: ocular pain, general discomfort, tearing, foreign body sensation, and burning. This questionnaire was administered prior to surgery as a baseline, and subsequently at 7, 30, and 90 days post-surgery. Simultaneously, the Ocular Surface Disease Index (OSDI) was applied at these same time intervals. RESULTS: The study encompassed a total of 17 patients (9 undergoing trabeculectomy and 8 undergoing Ahmed glaucoma valve implantation). The Ahmed glaucoma valve implantation group exhibited higher tearing levels at baseline (p=0.038). However, no statistically significant differences in symptoms were observed between the two surgeries at 7 and 30 days post-surgery. At the 90-day mark following surgery, patients who had undergone trabeculectomy reported a significantly higher foreign body sensation (p=0.004). Although OSDI scores did not differ between groups at baseline, the trabeculectomy group showed significantly higher OSDI scores than the Ahmed glaucoma valve implantation group at 7, 30, and 90 days after surgery (p<0.05). CONCLUSION: Post-surgery, patients who had undergone trabeculectomy experienced increased foreign body sensation. Trabeculectomy appears to cause greater early postoperative ocular discomfort compared to the Ahmed glaucoma valve implantation group.

Results of intrastromal corneal ring implantation in advanced keratoconus With the aim of postpoing or avoiding corneal transplantation.

PURPOSE: To evaluate the safety and efficacy of the surgery of intracorneal ring segment implantation with 320° of arc (320-ICRS) in patients with advanced keratoconus stage IV and maximum keratometry (Kmax) above 60 D. METHODS: A prospective, interventional case series study evaluating 25 eyes of 19 patients with keratoconus stage IV and Kmax > 60D in which 320-ICRS were implanted using VisuMax® femtosecond. Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), keratometric values (mean - mean-K, flat - K1, and steep - K2), maximum keratometry (Kmax), tomographic astigmatism, refractive astigmatism and asphericity (Q) were assessed preoperatively and at 3, 6 and 12 months after the procedure. RESULTS: The UDVA improved from 1.03 ± 0.28 LogMAR (20/200) to 0.54 ± 0.21 LogMAR (20/60), (p < 0.001), the CDVA (with glasses) improved from 0.63 ± 0.29 LogMAR (20/80) to 0.31 ± 0.16 LogMAR (20/40),(p = 0.004), K1 reduced from 54.41 ± 4.46 D to 49.36 ± 4.11 D (p < 0.001), K2 reduced from 61.15 ± 4.37 D to 53.715 ± 4.05 D, (p < 0.001), mean-K reduced from 57.55 ± 4,17 D to 51.44 ± 3,94 D (p < 0.001), Kmax reduced from 69.80 ± 8.20 D to 63.43 ± 6.31 D (p < 0.001) and asphericity (Q) changed from -1.57 ± 0.35 to -0.77 ± 0.56 (p < 0.001). A total of 89.9% patients reached BCVA wearing scleral contact lens  0.2 LogMAR(20/25). CONCLUSION: 320-ICRS to treat advanced keratoconus appears to be an efficacious and safe procedure, being a surgical alternative to delay or even prevent corneal transplantation.

Vision-Related Quality of Life in Patients With Keratoconus With Enantiomorphic Topography After Bilateral Intrastromal Corneal Ring Implantation.

PURPOSE: The aim of this study was to evaluate the quality of life (QOL) after intrastromal ring implantation in patients with keratoconus. METHODS: This was a prospective, randomized, interventional study. We analyzed 60 eyes of 30 patients aged 16 to 35 years who were treated at the Department of Ophthalmology and Visual Sciences, Federal University of São Paulo, Brazil. The Visual Function Questionnaire (VFQ-25) and Short-Form 36 Questionnaire (SF-36) were used before intracorneal ring segment (ICRS) implantation and at 3, 6, and 12 months after surgical intervention. RESULTS: The mean corrected visual acuity improved from a mean of 0.32 ± 0.2 logMAR (20/40) preoperatively to 0.14 ± 0.11 logMAR (20/25) 1 year postoperatively ( P = 0.001). The mean spherical equivalent varied from -7.24 ± 3.47 preoperatively to -4.13 ± 2.41 postoperatively ( P = 0.001). The overall composite score for the VFQ-25 improved from 55.1 preoperatively to 80.4 1 postoperatively ( P = 0.001). SF-36 showed statistically significant improvement in all scores. When analyzing the correlation between visual acuity and VFQ composite score, a significant correlation was found between both variables (Pearson correlation coefficient of -0.40, P = 0.001). CONCLUSIONS: Patients with keratoconus had increased psychological symptoms and lower QOL and improved psychosocial criteria associated with corneal remodeling and decreased visual dependence on others after surgery. Extrapolation of these data to the whole keratoconus population suggests that ICRS implantation could improve QOL in these patients.

Computational analysis of prosthesis production via topology optimization.

This work investigates the use of Topology Optimization (TO) to support the design of femur prosthesis to obtain more efficient solutions from the point of view of material distribution and internal forces. Computational tests were performed by the Interior-Point OPTimizer (IPOPT) method, seeking to explore the elastic mechanical characteristics of three real scenarios of daily loads on the femur. Numerical examples are presented to verify the novelty of the proposed method. The results obtained indicate that it is possible to reduce the volume of material up to 30% of the customize human femoral prosthesis, respecting all the boundary conditions.

Late-onset distal-apical intracorneal ring-segments keratopathy: an analysis of a large sample in a multicenter study.

PURPOSE: To review the prevalence and describe the characteristics, of cases with late-onset intracorneal ring segments (ICRS) keratopathy in a multicenter study. METHODS: A retrospective multicentric case-series study was performed in a specialized keratoconus service, from Buenos Aires, Argentina. An electronic clinical chart from patients with ICRS keratopathy between January 1999 and January 2019 was reviewed. We included cases with late-onset distal-apical ICRS keratopathy, which was defined as a persistent corneal lesion developed 12 months or later after implantation, located over, around, or closer to the ICRS. All the surgeries were performed by a manual corneal tunnel creation technique. Samples were taken to rule out infectious etiology. RESULTS: From 5217 eyes that underwent ICRS implantation, 13 cases (0.24%) were detected. The keratopathy onset was 72 ± 42.98 months (29-133) after ICRS implantation. Cultures were negative in all cases. An ICRS exchange was made for five cases in stage I and four in stage II. Four cases presented with partial ICRS extrusion in stage III. ICRS exchange was possible in two of them and a penetration keratoplasty was necessary for the rest. All cases remained stable 1 year after surgical procedures. CONCLUSIONS: A late-onset distal-apical ICRS keratopathy was detected with low prevalence (0.24%) in a large sample. It was classified into three stages according to its severity. Different treatments were selected for each stage, obtaining stable results 1 year after treatment.

Management of external ocular prosthesis by ocularists: results of an online survey conducted in Brazil and Spain.

PURPOSE: To analyse the ocularist's perspective on the management of the anophthalmic socket and external ocular prosthesis (EOP). METHODS: Ocularists from two countries were invited to participate in an online questionnaire. Data were collected on demographics, anophthalmic socket and EOP management (manufacturing, use, cleaning), complications, follow-up visits and multidisciplinary care. The frequency and proportions of the responses were statistically analysed. RESULTS: The questionnaire was addressed to 20 Brazilian and 17 Spanish ocularists, obtaining a response rate of 65% and 64.7%, respectively. 62.5% of respondents were men. The most common cause of anophthalmia in Brazil (69.2%) and Spain (36.4%) is an eye disease (chi square: p = 0.188). Polymethylmethacrylate (PMMA) is the most commonly used material in EOP manufacture (chi square: p = 0.448), and 70.8% reported using customized EOPs (chi square: p = 0.069). Deposits are frequently observed in both countries (chi square: p = 0.157). Changing the prosthesis is recommended after 5 to 10 years by Brazilian ocularists, and after less than 5 years of use by Spanish ocularists (81.8%) (chi square: p = 0.041). Annual follow-up is recommended by Spanish ocularists (45.5%), while semestral (38.5%) and case-dependent (38.5%) follow-up is recommended by Brazilian ocularists (chi square: p = 0.267). Daily cleaning is advocated by 61.5% of Brazilian ocularists and once a month by 45.5% of Spanish ocularists (chi square: p = 0.098), with 75% of ocularists from both countries not recommending EOP removal at night (Fisher´s exact test: p = 0.166). Good communication between ocularists and ophthalmologists was reported by 87.5% of our responders (chi square: p = 0.642). CONCLUSION: Although there are no unified protocols on the management of EOPs, Brazilian and Spanish ocularists follow similar guidelines. Differences between countries were the patients´ referral and the prosthesis´ useful life.

Surgical Management of Metastatic Pathologic Subtrochanteric Fractures: Treatment Modalities and Associated Outcomes.

BACKGROUND: Subtrochanteric pathological fractures (PFs) occur in approximately one-third of femur bone metastases. We seek to analyze surgical treatment strategies for subtrochanteric metastatic PFs and their revision rates. METHODS: A systematic review was performed using the PubMed and Ovid databases. Reoperations as a result of complications were analyzed according to initial treatment modality, primary tumor site, and type of revision procedure. RESULTS: We identified a total of 544 patients, 405 with PFs and 139 with impending fractures. The study population's mean age was 65.85 years with a male/female ratio of 0.9. Patients with subtrochanteric PFs who underwent an intramedullary nail (IMN) procedure (75%) presented a noninfectious revision rate of 7.2%. Patients treated with prosthesis reconstruction (21%) presented a noninfectious revision rate of 8.9% for standard endoprostheses and 2.5% for tumoral endoprostheses (p < 0.001). Revision rates because of infection were 2.2% for standard and 7.5% for tumoral endoprostheses. There were no infections within the IMN and plate/screws group (p = 0.407). Breast was the most common primary tumor site (41%) and had the highest revision rate (14.81%). Prosthetic reconstructions were the most common type of revision procedure. CONCLUSION: No consensus exists regarding the optimal surgical approach in patients with subtrochanteric PFs. IMN is a simpler, less invasive procedure, ideal for patients with a shorter survival. Tumoral prostheses may be better suited for patients with longer life expectancies. Treatment should be tailored considering revision rates, patient's life expectancy, and surgeon's expertise. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Prevalence of hypertensive phase and outcomes in patients with Ahmed valve implantation at one year of follow-up and evaluation of associated risk factors.

Purpose: To evaluate the prevalence of hypertensive phase (HP) and failure in patients who underwent Ahmed Glaucoma Valve (AGV) implantation and identify the possible risk factors for both HP and failure. Methods: A cross-sectional, observational study was conducted. Medical records of patients who underwent AGV implantation and had at least 1 year of follow-up were reviewed. HP was defined as an intraocular pressure (IOP) greater than 21 mmHg between the first week and the third postoperative month not attributable to other causes. Success was defined as an IOP between 6 and 21 mmHg, with preservation of light perception and no additional glaucoma surgeries. Statistical analysis was conducted to identify possible risk factors. Results: A total of 193 eyes of 177 patients were included. HP was present in 58%; a higher preoperative IOP and younger age were associated with HP. Pseudophakic or aphakic eyes had a lower HP rate. Failure was present in 29%; neovascular glaucoma, worse basal best corrected visual acuity (BCVA), higher baseline IOP, and postoperative complications were linked to a higher likelihood of failure. No difference in the HP rate between the failure and success groups was found. Conclusion: A higher baseline IOP and younger age are associated with HP development; pseudophakia and aphakia might be protective factors. Factors for AGV failure are a worse BCVA, neovascular glaucoma, postoperative complications, and a higher baseline IOP. At 1 year, a higher number of medications were needed to achieve IOP control in the HP group.

Spectrophotometric Analysis of Different Polymethyl Methacrylate Filters and their Importance in the Implantation of Corneal Rings.

PURPOSE: This study evaluated the luminous behavior applied to materials used in intraocular surgeries. METHODS: Discs of the different products were delivered in 19.00 mm × 3.00 mm. Each sample was fixed on support keeping it perpendicular to the spectrophotometer beam. Later, their analyses were carried out in the air/PMMA ratio. The graphs of individual profiles of the measurements along the length were constructed according to each of the filters from the spectrophotometric analysis. In addition, descriptive statistics of transmittance and absorbance for each wavelength presented were correlated for each filter. RESULTS: It is possible to observe that the minimum absorption measure was found in the Red Filter, especially in the blue and green light spectrum. CONCLUSION: Using filters in PMMA materials appears to improve visual quality in corneal implants, especially the red filter, due to greater absorbance of light leading to fewer light scattering phenomena through corneal rings. However, further studies comparing the effects of different filters on Intracorneal rings should be carried out to elucidate this field of study.

Surgical results of transcutaneous bone-anchored hearing aid comparing the C-shaped and linear incision techniques.

PURPOSE: The aim of the study is to compare the operative time and postoperative complication outcomes for bone-anchored hearing aid (BAHA) implants using two different techniques: the C-shaped incision technique and the linear incision technique. METHODS: An analysis was carried out of 38 patients implanted with transcutaneous BAHAs during a 4-year period in a single otolaryngology department. RESULTS: The implantation was carried out under general anesthesia. Operative time was significant lower with the linear technique compared to the C-shaped technique (76.55 min, SD 16.75 vs. 93.17 min, SD 19.82; p = 0.007). There was no difference in postoperative complications between the two techniques. CONCLUSIONS: The use of linear incision for transcutaneous BAHA system implantation is associated with a reduced surgery time compared to the C-shaped technique, with no increase in postoperative complications.

Management of glaucoma with Boston type 1 keratoprosthesis.

PURPOSE: To describe the frequency, clinical characteristics, complications, and management of glaucoma in eyes that underwent keratoprosthesis implantation. METHODS: Patients who underwent keratoprosthesis surgery between June 2010 and January 2020 were retrospectively evaluated for glaucoma association and prognoses. RESULTS: Among 17 patients who underwent keratoprosthesis surgery, 9 (52.9%) were associated with underlying or keratoprosthesis-induced glaucoma. Five eyes (29.4%) had underlying glaucoma and underwent a glaucoma drainage device implantation at least 6 months before keratoprosthesis surgery. One eye (5.9%) with normal intraocular pressure had glaucoma drainage device implantation at the same session with keratoprosthesis surgery due to high-risk characteristics of anterior segment structures. Four eyes with preexisting glaucoma showed progression after keratoprosthesis surgery. Additional antiglaucomatous treatment was commenced in two eyes whereas implantation of 2nd glaucoma drainage device was performed in two eyes. Postoperative complications in three eyes (100%) with glaucoma drainage device implanted 6 months before or at the same session with aphakic type keratoprosthesis surgery with partial vitrectomy included rhegmatogenous retinal detachment in two eyes and bacterial endophthalmitis in one eye. Migration of silicone oil through the tube to the subconjunctival area was seen after pars plana vitrectomy in one eye. None of the three eyes (0%) that underwent glaucoma drainage device implantation years before keratoprosthesis surgery experienced a posterior segment complication other than glaucomatous progression. Out of 11 eyes with no previous history of glaucoma, 3 (27.3%) showed high intraocular pressure and glaucomatous disc changes after keratoprosthesis surgery, which could be pharmacologically controlled. CONCLUSIONS: In this cohort, eyes with preexisting glaucoma were more difficult to manage compared to eyes with de novo glaucoma after keratoprosthesis surgery. Retinal complications appeared more often when glaucoma drainage device implantation was performed no more than 6 months before aphakic type keratoprosthesis surgery with partial vitrectomy.

Viscotrabeculotomy with anterior chamber irrigation versus Ahmed glaucoma valve implantation for silicone oil glaucoma in the pseudophakic eye.

PURPOSE: To compare viscotrabeculotomy with anterior chamber irrigation to Ahmed glaucoma valve implantation for secondary glaucoma following silicone oil removal. METHODS: A prospective study was conducted on 43 vitrectomized pseudophakic eyes with persistent glaucoma after silicone oil removal. Patients were randomized to either viscotrabeculotomy with anterior chamber irrigation or Ahmed glaucoma valve implantation. All patients were examined on day 1, week 1, and months 1, 3, 6, 9, 12, 18, and 24 postoperatively. Postoperative complications were noted. Success was defined as an intraocular pressure between 6 and 20 mmHg and with an intraocular pressure reduction of >30% compared with the preoperative intraocular pressure. RESULTS: There were 22 eyes in the viscotrabeculotomy with anterior chamber irrigation and 21 eyes in the Ahmed glaucoma valve implantation group. The mean preoperative and postoperative intraocular pressure in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 35.5 ± 2.6 mmHg and 35.5 ± 2.4 mmHg and 16.9 ± 0.7 mmHg and 17.9 ± 0.9 mmHg respectively (p˂0.0001). There was a statistically significant intraocular pressure reduction at all follow-up time points compared to preoperative values (p˂0.0001) in both groups. The unqualified success rate in the viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation groups were 72.73% and 61.9%, respectively. A minimal self-limited hyphema was the most common complication. CONCLUSIONS: Both viscotrabeculotomy with anterior chamber irrigation and Ahmed glaucoma valve implantation are effective in lowering the intraocular pressure in glaucoma after silicone oil removal with viscotrabeculotomy with anterior chamber irrigation providing greater reduction, higher success rates, and minimal complications.

Clinical and histopathological study of a hollow and posteriorly multiperforated polymethylmethacrylate implant in eviscerated rabbit eyes.

PURPOSE: The study aimed to evaluate the clinical and tissue response to a hollow polymethylmethacrylate orbital implant with a multiperforated posterior surface in an animal model after evisceration. METHODS: Sixteen New Zealand rabbits had their right eye eviscerated. All animals received a hollow polymethylmethacrylate implant 12 mm in diameter that is multiperforated in its posterior hemisphere. The animals were divided into four groups, and each one had the eye exenterated at 7, 30, 90, and 180 days post-evisceration. Clinical signs were assessed daily for 14 days post-evisceration and then every 7 days until 180 days. Inflammatory pattern, collagen structure, and degree of neovascularization generated with implant placement were analyzed with hematoxylin-eosin, picrosirius red, and immunohistochemistry staining. RESULTS: There were no signs of infection, conjunctival or scleral thinning, or implant exposure or extrusion in any animal during the study. On day 7, the new tissue migrated into the implant and formed a fibrovascular network through the posterior channels. Inflammatory response reduced over time, and no multinuclea-ted giant cells were found at any time. CONCLUSION: Hollow polymethylmethacrylate orbital implants with a multiperforated posterior surface enable rapid integration with orbital tissues by fibrovascular ingrowth. We believe that this orbital implant model can be used in research on humans.