Ab Interno Trabeculotomy Research Articles

Suture Trabeculotomy Ab Interno for Secondary Glaucoma Combined With Scleromalacia

To report 2 cases of secondary glaucoma combined with scleromalacia that were successfully treated with trabeculotomy ab interno. Retrospective case report : Trabeculotomy ab interno was used to treat secondary glaucoma combined with scleromalacia, which occurred due to refractory scleritis, in 2 cases. In case 2, goniosynechialysis was performed before the trabeculotomy to identify the trabecular meshwork. The sclera and conjunctiva were not incised in either case. The patients' postoperative intraocular pressure (IOP) levels (which were achieved without medication) were lower than their preoperative IOP levels (which were recorded during the administration of the maximum tolerable medication dosage); that is, they had dropped from 24 to 12 mm Hg in case 1 and from 33 to 11 mm Hg in case 2 by 12 postoperative months. No recurrent scleritis or postoperative worsening of the patient's scleromalacia was seen in either case. Trabeculotomy ab interno is a very valuable treatment for secondary glaucoma combined with scleromalacia.

Transient Ciliochoroidal Detachment After Ab Interno Trabeculotomy for Open-Angle Glaucoma: A Prospective Anterior-Segment Optical Coherence Tomography Study.

Although trabeculotomy is a glaucoma surgical procedure for modest intraocular pressure (IOP) reduction, some eyes exhibit very low IOP during the early postoperative period. To our knowledge, the reason and its effect have not been investigated. To investigate ciliochoroidal detachment (CCD) immediately after ab interno trabeculotomy and evaluate its effect on IOP immediately after surgery. This prospective, observational, case series was conducted at Kyoto University Hospital, Kyoto, Japan. Patients with open-angle glaucoma who underwent ab interno trabeculotomy using a microsurgical device by a single surgeon between July 1, 2014, and May 31, 2015, were included. Thirty-seven consecutive patients were enrolled, 33 of whom were included in the analysis. The dates of the analysis were August 1 to August 15, 2015. Imaging of CCD using anterior-segment optical coherence tomography (AS-OCT). The incidence of CCD immediately after ab interno trabeculotomy and its effect on IOP in the early postoperative period. The study cohort comprised 33 patients. Their mean (SD) age was 69.4 (13.2) years, and 19 (58%) were male. At postoperative day 3, CCD was detected in 14 of 33 eyes (42%) (CCD group) using AS-OCT. The CCD group had shorter axial length (mean [SD], 23.66 [1.67] vs 25.16 [1.59] mm) and thinner central corneal thickness (mean [SD], 505.9 [35.8] vs 533.9 [39.1] μm) than the non-CCD group. Only 5 eyes had CCD at postoperative day 10, and 4 of these eyes had CCD at 1 month after surgery. The postoperative IOPs at all follow-up periods were lower in the CCD group than in the non-CCD group, but the difference in the postoperative IOPs between the groups decreased as time passed. The mean (SD) IOPs for the CCD group vs the non-CCD group were 9.1 (3.0) vs 14.2 (5.8) mm Hg at day 1, 8.4 (2.4) vs 13.4 (5.0) mm Hg at day 3, 11.0 (3.0) vs 15.5 (6.3) mm Hg at day 10, 13.4 (2.4) vs 15.5 (3.3) mm Hg at 1 month, and 13.9 (3.4) vs 15.5 (4.0) mm Hg at 3 months. In several eyes in the CCD group, the AS-OCT images revealed a connection between the CCD and the anterior chamber via the trabeculotomy site. Ciliochoroidal detachment after ab interno trabeculotomy was not rare and was associated with low IOP immediately after surgery. Postoperative CCD may be partially attributed to the transient increase in uveoscleral aqueous outflow via the trabeculotomy site.

Assessment of Anterior Segment Measurements with Swept Source Optical Coherence Tomography before and after Ab Interno Trabeculotomy (Trabectome) Surgery.

Purpose. To compare the changes of anterior segment parameters, assessed by swept source anterior segment optical coherence tomography (AS-OCT) after combined Trabectome-cataract surgery and Trabectome-only surgery in open angle glaucoma patients. Methods. Thirty-eight eyes of 24 patients with open angle glaucoma were scanned with swept source AS-OCT before and 4 weeks after combined Trabectome-cataract or Trabectome-only surgery. Intraocular pressure, number of medications, and AS-OCT parameters, such as angle opening distance at 500 and 750 μm from the scleral spur (AOD500 and AOD750), trabecular-iris space area at 500 and 750 mm2 (TISA500, TISA750), angle recess area at 500 and 750 mm2 (ARA500, ARA750), trabecular iris angle (TIA), anterior chamber depth (ACD), anterior chamber width (ACW), and anterior chamber volume (ACV), were obtained before the surgery. These parameters were compared to evaluate whether the outcome of the surgery differed among the patients after the surgery. The width of the trabecular cleft was also measured for both groups. Results. The reduction of IOP and number of medications was found to be statistically significant in both groups (p < 0.001). ACD, ACV, and angle parameters such as AOD 500/750, TISA 500/750, ARA 500/750, and TIA500 showed significantly greater changes from the preoperative values to postoperative 1st month values in combined Trabectome-cataract surgery group (p < 0.05), whereas Trabectome-only group did not show statistically significant difference (p > 0.05). There was no statistically significant difference between two groups for the width of the trabecular cleft (p = 0.7). Conclusion. Anterior chamber angle parameters measured with swept source AS-OCT may be useful for evaluating glaucoma patients before and after Trabectome surgery with or without cataract surgery.

Efficacy and safety of combined cataract surgery with 2 trabecular microbypass stents versus ab interno trabeculotomy

To compare the outcomes of combined cataract surgery with trabecular microbypass stents and ab interno trabeculotomy in patients with open-angle glaucoma. University of Toronto, Toronto, Ontario, and University of Montreal, Montreal, Quebec, Canada, and Glaucoma Associates of Texas, Dallas, Texas, USA. Retrospective case series. Patients with primary open-angle, pseudoexfoliative, or pigmentary dispersion glaucoma were included. Primary outcome measures were intraocular pressure (IOP), postoperative medications, success (IOP ≤18 mm Hg, no glaucoma medications or reoperations), and postoperative adverse events. The average patient age was 76.5 years ± 12 [SD]. Forty-nine eyes had phacoemulsification and 2 had stent implantations; 52 eyes had phacoemulsification and trabeculotomy surgery with a 12-month postoperative follow-up. The analysis of variance indicated a significant reduction in mean IOP from baseline to 12 months for stent (19.6 ± 5.3 mm Hg to 14.3 ± 3.1 mm Hg; P < .001) and trabeculotomy (20.6 ± 6.8 mm Hg to 17.3 ± 6.5 mm Hg; P < .001) and lower mean IOP at 12 months in the stent group (P = .01). The median number of glaucoma medications decreased from baseline to 12 months in both groups and was lower in the stent group at 3, 6, and 12 months. Thirty-nine percent (19 eyes) in the stent group and 14% (7 eyes) in the trabeculotomy group achieved success at 12 months (P = .006). The incidence of hyphema was lower in the stent group (P = .008). Both types of surgery achieved a significant reduction in IOP and medication use at 12 months, with the stent group achieving higher success and a reduced incidence of postoperative hyphema. Dr. Ahmed is a consultant to and investigator for Glaukos Corp., Ivantis, Inc., Transcend Medical, Inc., and Aquesys, Inc., and has received speaker honoraria from Neomedix, Inc. Dr. Saheb has received travel funding from Glaukos Corp., Ivantis, Inc., and Transcend Medical, Inc., and a research grant from Ivantis, Inc. Dr. Harasymowycz has received a research grant from Ivantis, Inc. Dr. Fellman is a consultant to Endo Optiks, Inc., and has received honoraria from Optous and research funds from Ivantis, Inc., Glaukos Corp., and Transcend Medical, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Management of exfoliative glaucoma: challenges and solutions.

Exfoliative glaucoma is the most common type of secondary open-angle glaucoma worldwide. It is characterized by high intraocular pressure (IOP) and worse 24-hour IOP characteristics. In order to minimize progression, treatment of exfoliative glaucoma has to provide a low long-term mean IOP and good 24-hour IOP control. To achieve these goals, fixed-dose combination eye drops, argon and selective laser trabeculoplasty, and various forms of surgery (trabeculectomy, deep sclerectomy, viscocanalostomy, ab interno trabeculotomy, trabecular aspiration, and cataract surgery) all need to be considered during the long-term management of the disease. Since exfoliative glaucoma is a disease of the elderly, and is frequently associated with systemic vascular disease, interdisciplinary consultations are of great clinical importance. These management aspects and the current medical, laser, and surgical results are covered in this review, with a special focus on the needs of the general ophthalmologist.

Prospective, noncomparative, nonrandomized case study of short-term outcomes of 360° suture trabeculotomy ab interno in patients with open-angle glaucoma.

BackgroundIn this paper, we describe 360° suture trabeculotomy (360°LOT) ab interno and the short-term course in patients who underwent this procedure.MethodsWe prospectively studied 12 patients (12 eyes) with open-angle glaucoma who underwent 360°LOT ab interno at the Sato Eye Clinic between February and July 2014. The surgical procedure involved making a 1.7 mm temporal corneal incision, exposing an approximately 15° opening in the inner wall of Schlemm’s canal (nasal side) using a Trabectome with a gonioscope, and inserting a 5-0 nylon suture rounded at the tip into Schlemm’s canal opened via the anterior chamber. The suture was then threaded around Schlemm’s canal, and the tip of the suture that emerged on the other side was then advanced through the opening to make a circumferential incision. Intraocular pressure (IOP), number of anti-glaucoma medications used, complications, and the surgery completion rate were prospectively studied.ResultsMean IOP, which was 19.4 mmHg at baseline, showed a significant decrease at each of the monthly observation points, reaching 13.8 mmHg at 6 months after surgery (P=0.0004, paired t-test). The mean number of anti-glaucoma medications decreased from 3.2 at baseline to 1.1 at 6 months after surgery. IOP spikes ≥30 mmHg were seen in 25% of patients, but there were no other serious complications and the surgery completion rate was 92%.ConclusionThe 360°LOT ab interno procedure preserves the conjunctiva and sclera, and has a high surgery completion rate when using the anterior chamber approach, and could therefore be an effective short-term treatment of open-angle glaucoma.

Future Prospects: Assessment of Intraoperative Optical Coherence Tomography in Ab Interno Glaucoma Surgery

Purpose: Ab interno glaucoma surgery, such as trabecular aspiration or ab interno trabeculotomy, has been introduced as an alternative, non-filtering procedure to lower intraocular pressure in glaucoma patients. The purpose of the present study was to assess the feasibility of intraoperative spectral domain optical coherence tomography (iOCT) for improving ab interno glaucoma surgery.Materials and Methods: Intraoperative optical coherence tomography was performed to visualize the anterior chamber angle, the aspiration canula during trabecular aspiration, and the trabectome device during ab interno trabeculotomy. A commercially available 840-nm iOCT was used in a clinical setting, a 1310-nm spectral-domain OCT in an experimental setting.Results: In the clinical setting using the 840-nm iOCT, visualization of the aspiration canula and the trabectome device was possible, however, with rather limited visibility of the chamber angle and the trabecular meshwork. In the experimental setting, the 1310-nm OCT enabled excellent visualization of the chamber angle and detailed evaluation of the instrument–trabecular meshwork relation.Conclusions: Intraoperative use of optical coherence tomography may be helpful for ab interno glaucoma surgery. Adjustments of the commercially available iOCT, including longer wavelengths and oblique scanning options, are necessary for the clinical use.

Unterschiedliche Effekte der Trabektomoperation auf unterschiedliche Glaukomformen

Ab interno trabeculotomy using the trabectome device is a intraocular pressure (IOP) decreasing operation by ablation of the trabecular meshwork and the inner wall of Schlemm's channel. This prospective study analyses the effectiveness of the trabectome operation in 122 patients. The operation was conducted when topical medication was maxed out with the intraocular pressure (IOP) remaining above the desired target range. In addition to the evaluation of the whole study group further analysis concerned the effectiveness of the trabectome in different subclassifications of glaucoma. In some cases the procedure was combined with cataract surgery and subsequently the results were compared to the plain trabectome OP. The results were split into two groups: "complete success" (without postoperative medication) and "qualified success" (with medication). The evaluation was processed for the IOP levels ≤ 21 mmHg, ≤ 18 mmHg, ≤ 15 mmHg und ≤ 12 mmHg. Follow-up dates were 6 and 12 months after surgery. Baseline IOP was 20.15 ± 7.1 mmHg. After 6 months the average IOP of all patients was 16.53 ± 5.89 mmHg, after 12 months the IOP amounted to 15.6 ± 4.45 mmHg. At both follow-ups approximately 90 % of the "complete success" group exhibited an IOP ≤ 18 mmHg. Also at both follow-ups 75 % of the "qualified success" group achieved a range ≤ 18 mmHg - whereas 50 % gained an IOP ≤ 15 mmHg. In secondary glaucoma an IOP decrease of 36 % was achieved. In open-angle glaucomas and those with dysgenetic altered angles the operation evoked a pressure loss of ca. 20 %. The trabectome-only group as well as the group of combined surgery exhibited a significant lowering of IOP. This was accomplished by a significant reduction of eye drops. After surgery nearly half of all patients required none or 1 eye drop at most. The trabectome offers a safe and significant lowering of IOP for around 36 % and seems to be very effective in secondary glaucomas. In dysgenetic alterations and open-angle glaucoma a moderate lowering of IOP (ca. 20 %) may be expected. The amount of eye drops can be reduced for about 42 %. After surgery every second patient requires at most 1 eye drop. The technique can be combined with cataract surgery and permits a penetrating operation at a later date.

Minimally invasive glaucoma surgery using the trabectome

The main barrier reducing outflow of aqueous humor in open angle glaucomas is the juxtacanalicular trabecular meshwork. The trabectome removes this pathophysiologically altered tissue by electroablation, thus allowing for the collector channels draining Schlemm's canal to directly communicate with the anterior chamber. In studies published so far, about 30% decrease of intraocular pressure and a simultaneous 42% reduction of pressure-lowering eyedrops could be achieved in primary and secondary open angle glaucomas. A clear cornea tunnel is used to advance the trabectome to the trabecular meshwork, leaving the conjunctiva unaffected. Hence minimally invasive chamber angle surgery using this device is in particular suitable for patients with an altered ocular surface. Lowering of intraocular pressure and reduction of needed topical medication seems to be distinct in pseudoexfoliative glaucoma. Surgery with the trabectome and phacoemulsification can easily be combined in one procedure. Using a minimally invasive approach, the complication profile of the trabectome is rather advantageous, not exceeding the general risks of globe-opening surgery. Ab-interno trabeculotomy is a safe and effective method for treatment of patients with primary or secondary open angle glaucomas and moderate target pressures.

Corneal Crystalline Deposits Associated With Topically Applied Gatifloxacin

To report a case of corneal crystalline deposits from the use of gatifloxacin 0.5% topical antibiotic after combined cataract extraction and trabeculotomy ab interno surgery. A 59-year-old woman presented after combined cataract extraction and trabeculotomy ab interno with crystalline deposits in the anterior corneal stroma. Clinical examination and slit-lamp photography were performed. The slit-lamp examination showed inferior white crystal deposition in the anterior stroma with overlying punctate epithelial erosions 4 weeks postoperatively. The eye was asymptomatic, but the deposition was cosmetically noticeable to the patient. Serial slit-lamp photography demonstrated resolution of the crystalline deposits 30 days after the discontinuation of eye drops. The authors present a rare case of stromal crystallization from topical gatifloxacin treatment. Complete resolution of corneal deposits was seen 30 days after the discontinuation of the drops without sequelae.

Trabeculotomy ab interno with internal limiting membrane forceps for open-angle glaucoma

To describe a new technique to perform trabeculotomy ab interno on eyes with open-angle glaucoma (OAG). This was a retrospective study. We inserted a 25-gauge forceps that is usually used for internal limiting membrane peeling into the anterior chamber, and grasped and pulled the inner wall of Schlemm's canal away from the canal. The inner wall of Schlemm's canal was stripped for about 100° to 120° in 26 eyes of 23 patients. The intraocular pressure (IOP) and number of glaucoma medications were recorded before, and 1day, 1week, 2weeks, and 1, 3, 6, 10, 12, 15, 17, 19, 24, 27, 30, and 33months after the surgery. The intra- and postoperative complications were recorded. The mean ± standard deviation of the preoperative IOP was 20.0 ± 6.8mmHg with a range from 10 to 38mmHg (n = 26). The IOP was significantly reduced (P < 0.05; paired t-tests) at 1week, 2weeks, and 1, 3, 6, 10, 12, 15, 17, 24, 19, 27, 30, and 33months after the surgery. The mean preoperative number of glaucoma medications was significantly reduced (P < 0.001; paired t-tests) at 1week, 2weeks, and 1, 3, 6, 10, 12, 15, 17, 19, 24, 27, 30, and 33months after the surgery. No vision-threatening complications were found in any of the cases, but there were blood clots in the anterior chamber postoperatively in 92.3% of the cases. Trabeculotomy ab interno for OAG is effective but with some minor complications. A larger number of patients with longer follow-up periods are needed to determine the long-term effectiveness of this procedure.

Clinical Results of Ab Interno Trabeculotomy Using the Trabectome for Open-Angle Glaucoma: The Mayo Clinic Series in Rochester, Minnesota

To determine outcomes of ab interno trabeculotomy for treatment of open-angle glaucoma (OAG). Retrospective interventional single-surgeon, single-center case series. Data were collected from 246 patients undergoing ab interno trabeculotomy between September 1, 2006, and December 1, 2010, with 3 months' follow-up or longer. Kaplan-Meier analysis was performed using Criteria A (postoperative intraocular pressure [IOP] ≤21 mm Hg or ≥20% reduction from preoperative IOP) and Criteria B (IOP ≤18 mm Hg and ≥20% reduction in IOP). Failure included increased glaucoma medications or subsequent surgery. Failure risk factors were identified using Cox proportional hazards ratio (HR). Of 88 cases of ab interno trabeculotomy-only and 158 cases of ab interno trabeculotomy with cataract extraction, the retention rate was 70% for 1 year and 62% for 2 years. Preoperative mean IOP was 21.6 ± 8.6 mm Hg; the number of glaucoma medications was 3.1 ± 1.1. At 24 months postoperatively, mean IOP was reduced 29% to 15.3 ± 4.6 mm Hg (P < 0.001) and the number of glaucoma medications was reduced 38% to 1.9 ± 1.3 (P < 0.001) with a success rate of 62% (95% CI, 56%-68%) using Criteria A and 22% (95% CI, 16%-29%) using Criteria B. Failure risk factors using Criteria A included primary OAG (HR 3.14, P < 0.01, 95% CI, 1.91-5.17) and past argon laser trabeculoplasty (HR 1.81, P < 0.01, 95% CI, 1.18-2.77). Using Criteria B, the HR for pseudoexfoliative glaucoma was 0.43 (P < 0.01, 95% CI 0.27-0.67). Of the cases, 66 (26.8%) required subsequent surgery on an average of 10 months (2 days to 3.2 years) after ab interno trabeculotomy. For criteria involving IOP ≤18 mm Hg, the 24-month survival of ab interno trabeculotomy is low. This surgery is appropriate for patients requiring a target IOP of 21 mm Hg or above.

Update on Minimally Invasive Glaucoma Surgery (MIGS) and New Implants

Traditional glaucoma surgery has been challenged by the advent of innovative techniques and new implants in the past few years. There is an increasing demand for safer glaucoma surgery offering patients a timely surgical solution in reducing intraocular pressure (IOP) and improving their quality of life. The new procedures and devices aim to lower IOP with a higher safety profile than fistulating surgery (trabeculectomy/drainage tubes) and are collectively termed “minimally invasive glaucoma surgery (MIGS).” The main advantage of MIGS is that they are nonpenetrating and/or bleb-independent procedures, thus avoiding the major complications of fistulating surgery related to blebs and hypotony. In this review, the clinical results of the latest techniques and devices are presented by their approach, ab interno (trabeculotomy, excimer laser trabeculotomy, trabecular microbypass, suprachoroidal shunt, and intracanalicular scaffold) and ab externo (canaloplasty, Stegmann Canal Expander, suprachoroidal Gold microshunt). The drawback of MIGS is that some of these procedures produce a limited IOP reduction compared to trabeculectomy. Currently, MIGS is performed in glaucoma patients with early to moderate disease and preferably in combination with cataract surgery.

Delayed-Onset Symptomatic Hyphema After Ab Interno Trabeculotomy Surgery

To describe patients who have experienced delayed-onset hyphema after ab interno trabeculotomy surgery with the Trabectome (Neomedix Corp) for open-angle glaucoma. Retrospective case series. study population: Patients at Mayo Clinic, Rochester, Minnesota, who underwent Trabectome surgery between September 1, 2006, and December 31, 2010, and who had symptomatic hyphema at least 2 months after surgery. observation procedure: Patients with blurred vision at least 2 months after Trabectome surgery were examined for the presence of hyphema using a slit lamp and gonioscopy. main outcome measures: Proportion of patients experiencing delayed-onset symptomatic hyphema after Trabectome surgery. Associated factors and clinical course for these patients. Of 262 cases of Trabectome surgery, there were 12 cases of delayed-onset symptomatic hyphema (4.6%). The average age was 74.3 years (range, 66 to 82 years). Median time to onset of hyphema was 8.6 months (range, 2 to 31 months) after surgery. Symptom onset commonly occurred on awakening. The most common characteristic was maintaining a sleep position on the surgical side. Most hyphemas resolved within 1 to 2 weeks, except in 1 patient, who required trabeculectomy for a refractory intraocular pressure spike. This is a series of patients with symptomatic delayed-onset hyphema after Trabectome surgery in the absence of further surgeries or trauma. Likely mechanisms are exertion-related increase in episcleral venous pressure or ocular compression from sleeping on the surgical side, followed by sudden decompression and blood reflux. Symptomatic patients should identify and avoid associated triggers because delayed-onset hyphema may be associated with intermittent intraocular pressure spikes that may require medical or surgical treatment.

Combined Surgery in the Treatment of Patients with Cataract and Primary Open-angle Glaucoma

Cataract and glaucoma are the two leading causes of blindness worldwide and frequently co-exist in the ageing population. No uniform recommendations can be proposed when the two conditions are associated. In the presence of a visually significant cataract and uncontrolled glaucoma, clinicians should consider performing combined cataract surgery and trabeculectomy. Numerous phacotrabeculectomy techniques have been proposed. However, in the absence of strong evidence in support of a specific technique, surgeons’ preference and experience may dictate the choice. Unless contraindicated, mitomycin-C should be considered in all combined procedures. In addition, novel and minimally invasive glaucoma surgical procedures, such as ab interno trabeculotomy, have recently emerged and gained in popularity. In general, these procedures have shown the potential to be combined with phacoemulsification to further lower intraocular pressure (IOP) with relatively few post-operative complications. However, available data suggest that these techniques seem unlikely to be able to achieve a degree of IOP reduction comparable with that of trabeculectomy. Rigorous studies are necessary to better understand the long-term efficacy and safety profile of these novel procedures, when performed alone or in combination with cataract surgery.

Excimer laser trabeculotomy vs 180° selective laser trabeculoplasty in primary open-angle glaucoma. A 2-year randomized, controlled trial

To compare the effectiveness and safety of excimer laser trabeculotomy (ELT) ab interno vs selective laser trabeculoplasty (SLT) over 24 months of follow-up in patients with primary open-angle glaucoma (POAG) refractory to medical therapy. This prospective, randomized study included 30 consecutive eyes assigned randomly to either ELT or SLT group. ELT was carried out using a XeCl Excimer Laser with an emission wavelength of 308 nm. Eight spots were equally distributed at a distance of 500 microm from one another over the anterior trabeculum. The SLT patients were treated with a frequency-doubled q-switched neodymium:yytrium-aluminum-garnet laser (wavelength 532 nm). Approximately 50 adjacent, but not overlapping, laser spots were distributed over 180 degrees of the trabecular meshwork, using an energy level ranging from 0.7 to 1.0 mJ per pulse. The main outcome measure was intraocular pressure (IOP) lowering after ELT and SLT. Success was defined as >or=20% reduction in IOP without further glaucoma intervention. At 24 months, complete success rates were 53.3% for the ELT group and 40% for the SLT group (P=0.35, Fisher's exact test); qualified success rates were 33.3% for the ELT and 26.6% for the SLT group (P=0.5, Fisher's exact test).Mean IOP decreased from 25.0+/-1.9 to 17.6+/-2.2 mmHg (-29.6%; P<0.0001) in the ELT group and from 23.9+/-0.9 to 19.1+/-1.8 mmHg (-21%; P<0.0001) in the SLT group. Both ELT and SLT proved to be effective techniques in the treatment of POAG refractory to medical therapy.

Canal surgery in adult glaucomas

Outflow procedures for glaucoma surgery have remained popular in the last decade, including trabeculectomy, glaucoma drainage devices, and deep sclerectomy/viscocanalostomy. In the last few years, the surgical armamentarium for glaucoma has vastly increased. Surgeons are using more procedures aimed at creating bleb-free surgery. Schlemm's canal surgery is experiencing a renaissance. This article concentrates on three of the more commonly performed canal procedures: trabeculotomy ab interno (Trabectome), Canaloplasty, and trabeculotomy ab externo. Trabeculotomy ab interno performed with the Trabectome has been shown to lower intraocular pressure (IOP) almost 40% by 12 months with minimal complications. Trabectome alone, as well as combined with cataract surgery, appears to lower IOP quite well. Canaloplasty has also been shown to lower IOP by 38% and combined with cataract surgery, IOP was lowered 44% at 24 months. Trabeculotomy lowers IOP well, especially in older adults. Phacotrabeculotomy lowers IOP to 21 mmHg or less in 84% of patients with supplemental use of medications, and in 36% of patients without at 3 years. Canal surgery has proven to be an alternative to traditional glaucoma surgery, lowering IOP relatively well. Surgeons must be comfortable with the anatomy and proceed with the procedure in eyes that are amenable to various new surgical advances.

Excimer laser trabeculotomy: a new, minimally invasive procedure for patients with glaucoma

Excimer laser trabeculotomy (ELT) ab interno is a new surgical technique to reduce intraocular pressure (IOP) in patients with glaucoma or ocular hypertension. Our purpose was to examine IOP reduction and the use of antiglaucoma drugs (AGD) in patients treated with ELT and to evaluate the safety of this laser treatment. To increase the outflow of aqueous humor, ten microperforations of the trabecular meshwork were performed by an endoscope-guided photoablative laser probe (Excimer laser, AIDA, TUI-Laser, Munich; pulse energy: 1.2 mJ at fiber tip, pulse duration: 60 ns, repetition rate: 20 Hz). Average operation time usually was about 2 min. In our pilot study, one group of patients without cataract underwent ELT, the other group with cataract underwent phacoemulsification (PHACO) plus ELT. IOP, visual acuity, and AGD were determined preoperatively (T0) and 2-4 months (T1), 5-7 months (T2), 11-13 months (T3), and 22-26 (T4) months after surgery. Treatment was defined to be successful if (1) postoperative IOP was < or =21 mmHg, and (2) IOP reduction was at least 20%. ELT reduced the IOP from 24.1+/-0.7 (n=69) mmHg preoperatively to 18.8+/-0.4 (T1, n=66), 20.0+/-0.5 (T2, n=51), 18.8+/-0.8 (T3, n= 37), and 16.8+/-1.0 (T4, n=15) mmHg, respectively. However, 28% of the eyes needed repeat surgery due to insufficient IOP reduction. According to Kaplan-Meier statistics, the success rate was 60% (T1), 49% (T2), and 46% (T3), respectively. The number of AGD was 1.9+/-0.1 (T0), 1.2+/-0.2 (T1), 1.3+/-0.2 (T2), 1.8+/-0.2 (T3), and 1.5+/-0.3 (T4). Combined phacoemulsification plus ELT reduced the IOP from 22.4 mmHg+/-0.6 (T0, n=57) to 16.5+/-0.4 (T1, n=52), 16.1+/-0.5 (T2, n= 40), 16.4+/-0.4 (T3, n= 35), and 12.8+/-1.5 (T4, n=4) mmHg, respectively; 7% of the eyes treated with the combined procedure needed repeat surgery due to insufficient IOP reduction. According to Kaplan-Meier statistics, the success rate was 85% (T1), 74% (T2), and 66% (T3), respectively. The number of AGD was 1.1+/-0.2 (T0), 0.9+/-0.2 (T1), 1.1+/-0.2 (T2), 1.2+/-0.2 (T3), and 1.8+/-0.9 (T4). ELT, especially in combination with phacoemulsification, is a new, promising, minimally invasive laser treatment to reduce IOP for at least 1-2 years. ELT alone is less effective in IOP reduction.

The value of trabeculotomy in glaucoma surgery.

Trabeculotomy has received increasing interest as a glaucoma procedure not only in congenital glaucoma but also in adult-onset open-angle glaucoma. In this review, the development, surgical technique, mechanism of action, and results after trabeculotomy in different types of glaucoma are described. Combined trabeculotomy and trabeculectomy and combined cataract and trabeculotomy techniques are discussed. Some remarks are given on laser trabeculotomy ab interno and other developments of trabecular surgery.