Microhook Ab Interno Trabeculotomy Research Articles

Comparing Corneal Biomechanic Changes between Solo Cataract Surgery and Microhook Ab Interno Trabeculotomy

Background/Objectives: This study aimed to examine the postoperative changes in the corneal biomechanical properties between solo cataract surgery and solo microhook ab interno trabeculotomy (LOT). Methods: This retrospective case–control study included 37 eyes belonging to 26 patients who underwent solo cataract surgery and 37 eyes belonging to 31 patients who underwent solo µLOT. These two groups were matched according to their preoperative intraocular pressure (IOP), axial length (AL), and age. Corneal Visualization Scheimpflug Technology (Corvis ST) was used to obtain four biomechanical parameters representing the corneal stiffness or corneal deformation at the highest concavity, including stiffness parameter A1 (SP-A1), stress–strain index (SSI), peak distance (PD), and deflection amplitude max (DefAmpMax). These parameters were compared preoperatively and 6 months postoperatively, and between the two surgical groups. Results: Preoperatively, the patients’ IOP, age, and AL, as well as their results in four Corvis ST parameters, were similar between the two groups (p > 0.05). No significant difference was observed in SP-A1; however, PD and DefAmpMax were significantly larger, and SSI was significantly smaller postoperatively in the LOT group than in the cataract group. Conclusions: Corneal stiffness was reduced, and the cornea was more deformed with LOT than cataract surgery.

Short-term outcomes of Tanito microhook ab interno trabeculotomy combined with phacoemulsification in primary open-angle glaucoma - A pilot study.

The aim of the study was to assess the early postoperative efficacy and safety of Tanito microhook (TMH) ab interno trabeculotomy combined with phacoemulsification in patients with primary open-angle glaucoma (POAG). This prospective interventional study was conducted on consecutive patients with visually significant cataract and mild-moderate POAG. All patients underwent a temporal clear corneal phacoemulsification combined with TMH ab interno trabeculotomy. Postoperative evaluation was done on day 1, 1 month, and 3 months. The outcome measures included intraocular pressure (IOP) at different follow-ups and postoperative complications. In total, 30 eyes of 30 patients were included in the study. There were 16 (53.3%) females and 14 (46.7%) males with a mean age of 62.63 ± 6.7 years. The mean IOP reduced from 23.57 ± 1.65 to 17.33 ± 2.84 at 3 months (P < 0.001). All eyes had a corrected distance visual acuity ≥6/9 at 1 month postoperatively. Postoperative complications included corneal stromal edema in eight (26.7%) eyes, hyphema in four (13.3%) eyes, and IOP spike in one (3.3%) eye. TMH ab interno trabeculotomy combined with phacoemulsification in patients with mild-moderate POAG is an effective and safe procedure with fewer complications.

Comparing corneal biomechanic changes among solo cataract surgery, microhook ab interno trabeculotomy and iStent implantation

Minimally invasive glaucoma surgery has expanded the surgical treatment options in glaucoma, particularly when combined with cataract surgery. It is clinically relevant to understand the associated postoperative changes in biomechanical properties because they are influential on the measurement of intraocular pressure (IOP) and play an important role in the pathogenesis of open-angle glaucoma (OAG). This retrospective case–control study included OAG patients who underwent cataract surgery combined with microhook ab interno trabeculotomy (µLOT group: 53 eyes of 36 patients) or iStent implantation (iStent group: 59 eyes of 37 patients) and 62 eyes of 42 solo cataract patients without glaucoma as a control group. Changes in ten biomechanical parameters measured with the Ocular Response Analyzer and Corneal Visualization Scheimpflug Technology (Corvis ST) at 3 and 6 months postoperatively relative to baseline were compared among the 3 groups. In all the groups, IOP significantly decreased postoperatively. In the µLOT and control groups, significant changes in Corvis ST-related parameters, including stiffness parameter A1 and stress‒strain index, indicated that the cornea became softer postoperatively. In contrast, these parameters were unchanged in the iStent group. Apart from IOP reduction, the results show variations in corneal biomechanical changes from minimally invasive glaucoma surgery combined with cataract surgery.

Comparison of surgical outcomes between iStent inject W implantation and microhook ab interno trabeculotomy in combination with phacoemulsification in primary open-angle glaucoma patients.

To examine primary open-angle glaucoma patients after undergoing combined cataract surgery with microhook ab interno trabeculotomy (μLOT-Phaco) or iStent inject W implantation (iStent-Phaco), and then evaluate the surgical outcomes after a minimum of 6 months of follow-up. Between October 2020 and July 2022, 39 μLOT-Phaco eyes and 55 iStent-Phaco eyes that underwent surgery were evaluated in this retrospective, multicenter comparative case series. Data that included preoperative and postoperative intraocular pressure (IOP), number of glaucoma medications, and occurrence of complications were collected from medical records and then examined. Surgical failure was defined as patients exhibiting a < 20% reduction in the preoperative IOP or an IOP > 18 mmHg on two consecutive follow-up visits, or when patients were required to undergo reoperation. Success rates were determined based on a Kaplan-Meier survival analysis. At 3, 6 and 12 months postoperatively, there was a significant postoperative reduction in the IOP (p < 0.001) and in the medications scores (p < 0.001) for both of the groups. In the μLOT-Phaco and iStent-Phaco groups, the probabilities of success at 6 and 12 months were 55.3 and 45.5%, and 48.4 and 45.5% (p = 0.38; log-rank test), respectively. In the iStent-Phaco group, there was a significant decrease in the hyphema. Comparable surgical outcomes occurred for both the μLOT and iStent inject W procedures.

Which is More Effective and Safer? Comparison of Propensity Score-Matched Microhook Ab Interno Trabeculotomy and iStent Inject.

The purpose of this study was to compare the surgical outcomes between abinterno trabeculotomy (LOT) and iStent injectW implantation (iStent) both combined with cataract surgery, matching the background factors including age, intraocular pressure (IOP), medication score, central corneal thickness (CCT), and axial length. A total of 100 eyes from 75/79 patients with primary open-angle glaucoma were included in the LOT/iStent groups. The background factors were matched between the two groups using the propensity score. There were no significant differences in age, IOP, medication score, CCT, and axial length, preoperatively. The postoperative medication scores were 1.3 ± 1.2 and 1.2 ± 1.2 in the LOT and iStent groups. The postoperative IOPs were 12.8 ± 2.8 and 13.1 ± 2.4mmHg in the LOT and iStent groups, respectively. The changes in the medication score were - 0.64 ± 1.4 and - 0.44 ± 1.6 in the LOT and iStent groups, respectively. The changes in the IOP were - 2.1 ± 3.3 and - 1.5 ± 3.0mmHg in the LOT and iStent groups, respectively. These values were not significantly different between the two groups. The postoperative IOP and changes in the IOP were significantly associated with preoperative IOP and CCT. There was no significant difference in the occurrence of postoperative complications (hyphema, 11.0% and 6.0%, and transient ocular hypertension, 8.0% and 5.0%, in the LOT and iStent groups, respectively). LOT and iStent have similar surgical outcomes with sufficient safety. Postoperative IOP was significantly associated with preoperative IOP and CCT in both groups.

Comparison of the 1-year surgical outcomes of ab interno trabeculotomy using three types of microhooks.

We compared the 1-year surgical outcomes of microhook ab interno trabeculotomy (μLOT) using three types of microhooks. We retrospectively analyzed 81 eyes that underwent μLOT, in which three microhooks, the Sinskey hook, Tanito Micro-Hook-trabeculotomy-device (TMH), and Matsushita ed. TMH, were used. We collected the data from the medical records. We analyzed the success rates and risk factors. Failure was defined as the need for additional surgery for IOP reduction, loss of light perception, and IOP ≧22 mmHg and IOP reduction <20% (definition 1), IOP ≧17 mmHg and IOP reduction <20% (definition 2), IOP ≧15 mmHg and IOP reduction <25% (definition 3), or IOP ≧12 mmHg and IOP reduction <30% (definition 4) at two consecutive follow-up visits. Twenty-six eyes underwent μLOT using the Sinskey microhook (group S), 21 eyes using the TMH (group T), and 34 eyes using the Matsushita ed. TMH (group M). The mean postoperative IOP and IOP-lowering medication score decreased significantly. The respective success rates among groups S, T, and M did not differ significantly (definition 1, 65.4%, 61.9%, and 55.9%; definition 2, 42.3%, 47.6%, and 32.3%; definition 3, 15.4%, 28.6%, and 23.5%; definition 4, 0%, 9.5%, and 2.9%). In group S, the hyphema-related IOP spikes decreased within 2 weeks postoperatively, and in group M, the non-hyphema-related IOP spikes decreased significantly. The 1-year surgical outcomes and complications after μLOT did not differ significantly among the three microhooks. The differences in the microhook tips might be associated with postoperative transient IOP spikes.

Vision-Related Quality of Life following Combined Cataract and Minimally Invasive Glaucoma Surgery or Cataract Surgery Alone in Glaucoma Patients.

This study examined glaucoma patients after undergoing combined cataract and minimally invasive glaucoma surgery (MIGS), microhook ab interno trabeculotomy and goniotomy with the Kahook Dual Blade (KDB), or cataract surgery alone, and it then evaluates their vision-related quality of life (VR-QOL) following the procedure. A total of 75 eyes of 75 consecutive glaucoma patients in this prospective cohort study underwent phacoemulsification (Phaco) or phaco and MIGS (Phaco-TLO) between October 2019 and March 2022. In all cases, the National Eye Institute Visual Function Questionnaire (VFQ-25) was used to evaluate the 20 eyes in the Phaco group and the 55 eyes in the Phaco-TLO group before and at 2 months after surgery. There was a significant increase in the visual acuity (logMAR) at 2 months post-operatively (Phaco group; 0.34 ± 0.10 to -0.07 ± 0.1, p < 0.0001, Phaco-TLO group; 0.37 ± 0.43 to 0.09 ± 0.32, p < 0.0001). The median (25-75th percentile) total VFQ scores in the Phaco group before and at 2 months after surgery were 71.1 (62.4-80.6) and 79.4 (69.0-84.0), respectively. (p = 0.006). The median (25-75th percentile) total VFQ scores in the Phaco-TLO group before and at 2 months after surgery were 69.8 (55.3-78.6) and 74.7 (65.1-83.3), respectively. (p = 0.005). Glaucoma patients who underwent not only cataract surgery alone but also combined cataract surgery and MIGS exhibited significant improvement in the VR-QOL.

Favorable effect of ripasudil use on surgical outcomes of microhook ab interno trabeculotomy.

We have previously demonstrated that prolonged use of glaucoma medications was associated with a poor surgical outcome of ab interno trabeculotomy (µTLO). Given that almost all types of glaucoma eye drop either enhance the drainage through the uveoscleral pathway or reduce aqueous humor production, we hypothesized that prolonged use of these medications might cause disuse atrophy of the conventional pathway. In contrast, ripasudil increases the conventional outflow and eventually shows a favorable outcome of µTLO. This study aimed to evaluate the effect of ripasudil use on µTLO outcomes. The medical charts of 218 patients who underwent µTLO were analyzed retrospectively. We compared the 1-year outcome between ripasudil users versus nonusers by using propensity score matching. We set the covariates as age, sex, glaucoma types, preoperative intraocular pressure (IOP), the mean deviation values of visual field tests, the presence or absence of concomitant cataract surgery, trabecular meshwork incision range, the presence or absence of any glaucoma medication except ripasudil and duration of glaucoma medical therapy. Success was defined as a postoperative IOP between 5 and 21mmHg, a ≥ 20% IOP reduction from baseline, and no additional glaucoma surgery at postoperative 1year. Fifty-seven patients each were allocated to the ripasudil users or nonusers. The 1-year success rates were 74% in ripasudil users and 51% in nonusers (p = 0.01). Kaplan‒Meier survival curves also showed that the ripasudil users had a higher survival distribution (p = 0.01). The patients who took ripasudil showed a favorable 1-year outcome of µTLO.

Comparison of Mid-Term Outcomes between Microhook ab Interno Trabeculotomy and Goniotomy with the Kahook Dual Blade.

This study retrospectively examined the mid-term surgical outcomes between microhook ab interno trabeculotomy (μLOT) and goniotomy when one was using the Kahook Dual Blade (KDB) in combination with phacoemulsification in primary open-angle glaucoma and exfoliation glaucoma patients. Between December 2016 and December 2020, the current study examined 47 μLOT and 52 KDB eyes that underwent surgery. When there was a &lt; 20% reduction in the preoperative intraocular pressure (IOP) or when the IOP was &gt; 18 mmHg (criterion A), the IOP was &gt; 14 mmHg (criterion B) at two consecutive follow-up visits, or when there was a requirement for reoperation, these were all considered to indicate that the surgery failed. A genetic algorithm that used the preoperative IOP was used to determine the score matching. After score matching, a total of 27 eyes were evaluated. In the μLOT and KDB groups, the mean postoperative follow-up periods were 31.2 ± 13.3 and 37.2 ± 16.3 months, respectively. The results for both of the groups show there were significant postoperative reductions in the IOP (p &lt; 0.05) and medication scores (p &lt; 0.05) at 6, 12, 24 and 36 months. At 12, 24, and 36 months, the probabilities of success in the μLOT and KDB groups for criterion A were 70.4% and 48.2%, 61.9% and 48.2%, and 55.0% and 48.2% (p = 0.32; log-rank test), respectively. For criterion B, the results for the two groups were 55.6% and 33.3%, 44.4% and 33.3%, and 44.4% and 33.3% (p = 0.15; log-rank test), respectively. Similar postoperative complications were found between the groups. Comparable mid-term surgical outcomes were found for the uses of μLOT and KDB.

Microhook ab interno trabeculotomy for secondary glaucoma in patients with hereditary transthyretin amyloidosis.

To report surgical outcomes of a Microhook ab interno trabeculotomy (µLOT) procedure for glaucoma secondary to hereditary transthyretin amyloidosis (ATTRv). Retrospective case series. Medical records of patients with glaucoma secondary to ATTRv with transthyretin Val30Met variant, who underwent µLOT, were retrospectively reviewed. Surgical success was categorized according to the postoperative intraocular pressures (IOPs, mmHg) as follows: (a) 6 ≤ IOP ≤ 21; (b) 6 ≤ IOP ≤ 18; and (c) 6 ≤ IOP ≤ 15, without light perception loss or additional glaucoma surgery. Secondary outcomes were glaucoma medication scores and postoperative complications. This study included 18 eyes (13 patients, 6 men). The mean follow-up period was 25.2±9.8 months (7-38 months). Kaplan-Meier analysis indicated success rates of (a) 1.00 at 6, 1.00 at 12, and 0.43 at 24 months; (b), 1.00 at 6, 0.93 at 12, and 0.43 at 24 months; (c) 0.94 at 6, 0.75 at 12, and 0.27 at 24 months after operation. Postoperative IOPs were significantly reduced from the baseline of 25.2±5.8 mmHg to 11.5±2.7 at 3, 12.3±4.1 at 6, and 13.8±3.9 at 12 months (Dunnett's test). Medication scores were also improved at 3 and 6 months but without a significant reduction at 12 months. There were no severe complications requiring surgical intervention except for additional glaucoma surgery. µLOT for secondary glaucoma in ATTRv is safe and effective 1 year after surgery, but the effects diminish after 2 years.

Transient ciliochoroidal detachment after microhook ab interno trabeculotomy: Its frequency and potential risk factors.

To investigate ciliochoroidal detachment (CCD) frequency and risk factors after performing microhook ab interno trabeculotomy (μLOT). A retrospective evaluation of 62 eyes of 62 patients who underwent μLOT and were subsequently examined by anterior-segment optical coherence tomography (AS-OCT) found CCD at 1 day, and 1 and 2 months after surgery. In the 62 patients (mean age 67.3 ± 13.9 years), AS-OCT detected CCD in 18 eyes (29%) at 1 day after surgery, which disappeared within 1 month. Comparisons between the CCD vs. the non-CCD group showed the mean IOPs were 11.7 ± 1.5 mmHg vs. 14.4 ± 1.0 mmHg at day 1 (P = 0.13), 12.2 ± 1.1 mmHg vs. 14.8 ± 0.7 mmHg at day 7 (P = 0.06), 12.2 ± 0.7 mmHg vs. 12.9 ± 0.5 mmHg at 1 month (P = 0.48), and 11.3 ± 0.7 mmHg vs. 12.7 ± 0.5 mmHg at 2 months (P = 0.09). For postoperative IOP, there were no significant differences observed. After undergoing μLOT, multiple regression analysis demonstrated that the CCD development might be influenced by the presence of a thinner central corneal thickness. Approximately one-third of all patients exhibited CCD after μLOT. A thinner central corneal thickness was found to be a risk factor for developing CCD.

Comparison of minimally invasive glaucoma surgery with trabecular micro-bypass stent and microhook ab interno trabeculotomy performed in conjunction with cataract surgery.

To evaluate the effectuality and safety of cataract surgery combined with either ab interno trabeculotomy by the microhook (µLOT) or a single iStent® trabecular bypass implantation (iStent) in eyes with cataract and mild-to-moderate glaucoma. This study enrolled subjects with mild-to-moderate open angle glaucoma with visually significant cataract who used two or more ophthalmic antiglaucoma agents between 60 and 90y of age. Patients underwent cataract surgery cooperated with either implantation of an iStent (iStent-phaco) or excisional goniotomy with the µLOT (µLOT-phaco). Patients underwent µLOT-phaco in the eye with lower the mean deviation, according to the Humphrey field analyzer, while iStent-phaco was carried out on the other eye. Intraocular pressure (IOP) pre- and post-surgery, alterations in anterior chamber flare (ACF), and corneal endothelial cell density (ECD) were estimated. Twenty subjects were enrolled (mean age: 73.6±7.3y). The mean medicated preoperative IOP was 16.7 mm Hg in the µLOT and 16.2 mm Hg in the iStent eyes. The mean final IOP at 12mo was 13.6 mm Hg in the µLOT eyes and 13.6 mm Hg in the iStent eyes, representing a 17.8% and 17.2% reduction, respectively. The preoperative ACF in the µLOT eyes was 9.5 pc/ms and it returned to normal in 30d postoperatively, with a value of 11.4 pc/ms. In the iStent eyes, ACF was 9.6 pc/ms preoperatively and it returned to normal by 7d postoperatively (11.2 pc/ms at day 7), demonstrating that postoperative inflammation was less in the iStent eyes. The corneal ECD in both groups was not significantly decreased. In this study, iStent and µLOT are both effective through 12mo of follow-up. Safety is more favorable in the iStent eyes, based on early anterior chamber inflammation.

Outcomes of Microhook ab Interno Trabeculotomy in Consecutive 36 Eyes with Uveitic Glaucoma.

Microhook trabeculotomy (μLOT), recently developed by Tanito belongs to minimally invasive glaucoma surgery and contributes to intraocular pressure (IOP) control in eyes with glaucoma resistant to medical therapy. In this study, we aimed to investigate the effectiveness and safety of μLOT for uveitic glaucoma. The medical records of consecutive 36 eyes from 30 patients who underwent μLOT and were followed up over post-operative 1 year were reviewed. The surgical success (IOP = 5–20 mmHg and ΔIOP ≥ 20% with additional anti-glaucoma drugs) was achieved in 67% of eyes at post-operative 12 months. The median IOP significantly decreased from 30.5 mmHg pre-operatively to 15 mmHg at 12 months post-operatively (p = 0.001), and the median glaucoma drug score changed from 5 pre-operatively to 2.5 at 12 months post-operatively (p = 0.301). Intraocular inflammation scores at post-operative 6 weeks did not show a significant worsening as compared to pre-operatively, and 8 (22%) eyes exhibited exacerbation of inflammation during the 12-month follow-up period. Post-operative complications were confirmed in 58% of eyes, but most of them were mild and transient or successfully managed. With its favorable benefit–risk profile, μLOT would be an option worth considering as the first glaucoma surgery for uveitic glaucoma.

One-year outcomes and predictable factors for microhook ab interno trabeculotomy.

To investigate the one-year outcomes and factors that influence the results of microhook ab interno trabeculotomy (µLOT). The medical records of consecutive patients with open angle glaucoma who underwent µLOT (including combination of µLOT and cataract surgery) between February 2018 and July 2019 were retrospectively reviewed. Surgical success was defined as the following: an intraocular pressure (IOP)≤21 mm Hg or IOP≤preoperative IOP with a reduced number of glaucoma eye drops, without additional glaucoma surgery, and assessed using Kaplan-Meier survival analysis. A multivariate Cox proportional-hazards regression model was used to investigate the factors associated with surgical failure. The 59 eyes of 59 patients comprising 28 eyes with primary open angle glaucoma (POAG) and 31 with secondary open angle glaucoma (SOAG) were included. The mean IOP and number of glaucoma eye drops significantly decreased from 25.3±7.2 mm Hg and 3.9±1.1, preoperatively to 16.1±4.4 mm Hg (P<0.01) and 2.1±1.8 (P<0.01), respectively, 12mo postoperatively, with a cumulative success rate of 63.1%. The one-year success rate was significantly higher in POAG eyes than in SOAG eyes (80.0% vs 48.0%; P=0.011, log-rank test). Multivariate analyses revealed SOAG [P=0.017, adjusted hazard ratio (aHR): 3.468, 95%CI: 1.246-9.654] and the postoperative IOP spike (IOP>25 mm Hg within 2wk post-surgery; P<0.001, aHR: 5.382, 95%CI: 2.113-13.707) as independent factors associated with surgical failure. The µLOT is a good treatment option for POAG eyes. However, the postoperative course should be carefully followed in cases with postoperative IOP spike.

Comparison of Postoperative Hyphemas between Microhook Ab Interno Trabeculotomy and iStent Using a New Hyphema Scoring System.

We have been using our in-house scoring system of hyphemas, i.e., Shimane University RLC postoperative hyphema scoring system (SU-RLC), which we designed to classify postoperative hyphema. SU-RLC classifies the severities of hyphemas based on three factors, i.e., red blood cells (RBCs) (R) 0–3, layer formation (L) 0–3, and clot (C) 0–1, by slit-lamp observation. To test the clinical usefulness of the SU-RLC for quantifying the postoperative hyphema severity, the SU-RLC scores were compared between eyes that underwent different minimally invasive glaucoma surgery (MIGS) procedures, i.e., Tanito microhook ab interno trabeculotomy and cataract extraction (TMH-CE) (n = 64 eyes of 64 subjects; mean age ± standard deviation, 72.4 ± 8.1 years) and iStent-CE (n = 21 eyes of 21 subjects; 76.1 ± 10.6 years). Compared to the iStent-CE, higher hyphema scores with the TMH-CE were found for the R scores on postoperative days 1, 2, and 3; for the L score on postoperative day 1; and for the C score on postoperative day 2. The sums of the R, L, and C scores (RLC) on postoperative day 1 were 3.2 ± 1.1 with the TMH-CE and 1.1 ± 1.3 with the iStent-CE; the scores reached almost 0 by 2 weeks in both groups. Significant differences in the RLC scores between the surgical groups were found on postoperative days 1, 2, and 3. Multivariate analyses showed that the TMH-CE rather than iStent-CE was associated with higher R, C, and RLC scores; anticoagulant/antiplatelet use was associated with higher R score; and myopia was associated with a higher C score. In the TMH-CE group, myopia was associated with a higher C score. In the iStent-CE group, anticoagulant/antiplatelet use was associated with higher R and RLC scores; and higher postoperative 1-day intraocular pressure was associated with a higher C score. The SU-RLC successfully detected the difference in hyphema severity between different MIGS procedures; thus, we concluded that our classification system may be feasible to evaluate hyphemas after glaucoma surgery.

Corneal Higher-Order Aberrations after Microhook ab Interno Trabeculotomy and Goniotomy with the Kahook Dual Blade: Preliminary Early 3-Month Results.

We examined postoperative corneal higher-order aberrations (HOAs) present after combined phacoemulsification with either microhook ab interno trabeculotomy (μLOT-Phaco) or goniotomy, using the Kahook Dual Blade (KDB-Phaco). Retrospective study: A total of 45 eyes underwent μLOT-Phaco and KDB-Phaco (LOT-Phaco) procedures, with 21 eyes that underwent cataract surgery alone used as controls. Visual acuity and corneal HOAs, coma-like aberrations, and spherical-like aberrations were analyzed before and at 1, 2, and 3 months after the surgeries. Risk factors that could potentially influence HOAs were evaluated. No significant postoperative changes were noted for corneal HOAs, coma-like aberrations, and spherical-like aberrations after cataract surgery alone. The mean corneal HOAs, coma-like aberrations, and spherical-like aberrations were 0.222 ± 0.115 μm, 0.203 ± 0.113 μm, and 0.084 ± 0.043 μm at baseline and 0.326 ± 0.195 μm (p < 0.001), 0.302 ± 0.289 μm (p = 0.03), and 0.150 ± 0.115 μm (p < 0.001) at 3 months after LOT-Phaco, respectively. Results of the analysis for risk factors suggested that a longer incision in Schlemm’s canal could influence corneal HOAs, coma-like aberrations, and spherical-like aberrations after LOT-Phaco. Although no significant postoperative changes were observed in corneal HOAs and coma-like or spherical-like aberrations after cataract surgery alone, a significant increase in corneal HOAs and coma-like or spherical-like aberrations remained after the LOT-Phaco procedure.

Effects of Preoperative Intraocular Pressure Level on Surgical Results of Microhook Ab Interno Trabeculotomy.

To assess the roles of preoperative intraocular pressure (IOP) level on the IOP reducing efficacy of microhook ab interno trabeculotomy (µLOT), 126 consecutive open-angle glaucomatous eyes (90 primary open angle glaucoma, 36 exfoliation glaucoma) of 126 Japanese subjects (60 men, 66 women; mean age ± standard deviation, 70.5 ± 11.4 years) who underwent µLOT alone (25 eyes, 20%) or combined µLOT and cataract surgery (101 eyes, 80%) were retrospectively included, and subdivided into four groups based on the quartile of preoperative IOP: Q1, ≤15 mmHg; Q2, 15–18 mmHg, Q3, 18–21 mmHg, and Q4, >21 mmHg. Preoperative and 12 months postoperative IOPs and numbers of antiglaucoma medications were compared among IOP groups. Factors associated with postoperative IOP were assessed using multivariate analysis, and the success of IOP control was assessed with various definitions. Postoperatively, IOP was significantly higher in Q3 (p < 0.0146) and Q4 (p = 0.0320) groups than Q1 group, while the number of medications was not significantly different among four IOP groups (p = 0.1966). Older age was associated with lower postoperative IOP, and higher preoperative IOP was associated with higher postoperative IOP, while sex, glaucoma type, surgical procedure, lens status, extent of trabeculotomy incision, and preoperative number of medications were not associated with postoperative IOP. The success rates for IOP ≤ 18 and ≤15 mmHg were higher in lower preoperative IOP groups (i.e., Q1 and Q2) than higher preoperative IOP groups (Q3 and Q4), while the success rate for ≥20% IOP reduction was higher in higher preoperative IOP groups than in lower preoperative IOP groups; the success rate for ≥0% IOP reduction was equivalent among groups. By reviewing the previous studies in ab interno trabeculotomy/goniotomy procedures, positive correlation between preoperative and postoperative IOPs was preserved throughout the studies and surgical procedures. After the µLOT, larger %IOP reduction was achieved in higher preoperative IOP groups than in lower preoperative IOP groups, while postoperative IOP was still lower than in lower preoperative IOP groups.

Comparison of Efficacy between 120° and 180° Schlemm's Canal Incision Microhook Ab Interno Trabeculotomy.

We compared surgical outcomes in patients with either primary open-angle glaucoma or exfoliation glaucoma after undergoing combined phacoemulsification with either a 120° or 180° incision during a Schlemm’s canal microhook ab interno trabeculotomy (μLOT-Phaco). This retrospective comparative case series examined 52 μLOT-Phaco eyes that underwent surgery between September 2017 and December 2020. Surgical qualified success was defined as an intraocular pressure (IOP) of ≤20 mmHg, ≥20% IOP reduction with IOP-lowering medications, and no additional glaucoma surgery. Success rates were evaluated by Kaplan-Meier survival analysis. The number of postoperative IOP-lowering medications and occurrence of complications were also assessed. Mean preoperative IOP in the 120° group was 16.9 ± 7.6 mmHg, which significantly decreased to 10.9 ± 2.7 mmHg (p < 0.01) and 11.1 ± 3.1 mmHg (p = 0.01) at 12 and 24 months, respectively. The mean number of preoperative IOP-lowering medications significantly decreased from 2.8 ± 1.4 to 1.4 ± 1.4 (p < 0.01) at 24 months. Mean preoperative IOP in the 180° group was 17.1 ± 7.0 mmHg, which significantly decreased to 12.1 ± 3.2 mmHg (p = 0.02) and 12.9 ± 1.4 mmHg (p = 0.01) at 12 and 24 months, respectively. The mean number of preoperative IOP-lowering medications significantly decreased from 2.9 ± 1.2 to 1.4 ± 1.5 (p < 0.01) at 24 months. The probability of qualified success at 24 months in the 120° and 180° groups was 50.4% and 54.6%, respectively (p = 0.58). There was no difference observed for hyphema formation or IOP spikes. Surgical outcomes were not significantly different between the 120° and 180° incisions in Schlemm’s canal.

Refractive Status in Eyes Implanted with Toric and Nontoric Intraocular Lenses during Combined Cataract Surgery and Microhook Ab Interno Trabeculotomy.

Purpose To compare the refractive status between eyes implanted with toric and nontoric intraocular lenses (IOLs) during combined cataract surgery and microhook ab interno trabeculotomy (μLOT), a minimally invasive glaucoma surgery (MIGS). Methods Twenty eyes of 20 patients who had open-angle glaucoma, cataract, and preexisting regular corneal astigmatism exceeding 1.5 diopters (D) and underwent combined μLOT and phacoemulsification were recruited retrospectively. Ten eyes were implanted with a toric IOL and 10 eyes with a nontoric IOL. The primary outcomes were the uncorrected visual acuity (UCVA) and refractive cylinder at 3 months postoperatively. Results The mean UCVA of the toric IOL group (logarithm of the minimum angle of resolution (logMAR), 0.23 ± 0.25) was significantly better than that of the nontoric IOL group (logMAR, 0.45 ± 0.26) at 3 months postoperatively (p < 0.05). The mean absolute residual refractive cylinder of the nontoric IOL group (2.25 ± 0.62 D) was significantly greater than that of the toric IOL group (1.30 ± 0.68 D) (p < 0.05). Postoperatively, 60% of eyes in the toric IOL group and 10% in the nontoric IOL group had an absolute refractive astigmatism level of 1.5 D or less. Surgically induced astigmatism (0.77 ± 0.43 D for toric group and 0.60 ± 0.32 D for nontoric group) and IOP reduction (33.9 ± 15.6% for toric group and 29.4 ± 11.7% for nontoric group) were not different between groups. Conclusions Use of toric IOL during combined cataract surgery and μLOT is possible and better than not, but physician should prevent their patient of persisting residual astigmatism. The study was registered at https://www.umin.ac.jp/, and the clinical trial accession number is https://clinicaltrials.gov/ct2/show/UMIN000043141.

Fellow-Eye Comparison between Phaco-Microhook Ab-Interno Trabeculotomy and Phaco-iStent Trabecular Micro-Bypass Stent.

The aim of this study is to compare the surgical efficacy and safety between microhook ab-interno trabeculotomy (µLOT) and iStent trabecular micro-bypass stent implantation when both were combined with cataract surgery in both eyes of patients. Sixty-four glaucomatous eyes (32 participants; mean age, 75.9 ± 7.6 years; 15 men, 17 women) were included retrospectively. Intraocular pressure (IOP), number of antiglaucoma medications, best-corrected visual acuity (BCVA), anterior chamber flare (ACF) and corneal endothelial cell density (CECD) were evaluated preoperatively, as well as 2, 3, 6, and 12 months postoperatively. Surgical complications and interventions were compared between the procedures. The preoperative IOP and medications with µLOT (18.8 ± 5.7 mmHg and 3.0 ± 1.2, respectively) were higher than with the iStent (15.5 ± 3.4 mmHg and 2.7 ± 1.2, respectively) (p = 0.0001 and p = 0.0437, respectively). At 12 months, the µLOT values (12.6 ± 2.3 mmHg and 2.3 ± 0.9, respectively) were identical to iStent (12.8 ± 2.5 mmHg and 2.3 ± 0.9, respectively) (p = 0.0934 and p = 0.3251, respectively). At 12 months, the IOP decreased more with µLOT (6.2 mmHg, 29.5%) than iStent (2.7 mmHg, 15.6%) (p = 0.0003). The decrease in medications was greater with µLOT (0.7) than iStent (0.4) (p = 0.0437). Survival rate of IOP control ≤15 mmHg and IOP reduction ≥20% was significantly higher after µLOT (40.6% at 12 months) than iStent (18.8%) (p = 0.0277). The frequency of layered hyphema was significantly greater with µLOT (8 eyes, 25%) than iStent (0 eyes, 0%) (p = 0.0048). The increase in the ACF at 2 weeks postoperatively was significantly greater with µLOT than iStent (p = 0.0156), while changes in the BCVA and CECD were identical between groups. The fellow-eye comparison showed that the IOP reduction was greater with µLOT than iStent when combined with cataract surgery.