Motility Changes and Diplopia After Baerveldt Glaucoma Drainage Device Implantation or After Trabeculectomy

Efficacy of Micropulse Laser Cyclophotocoagulation Therapy in Primary Angle Closure Glaucoma

PRCIS

In primary angle closure glaucoma (PACG), micropulse cyclophotocoagulation resulted in a significant reduction in intraocular pressure (IOP), and the number of antiglaucoma medications without any sight-threatening complications. However, the IOP lowering efficacy decreased over time.

PURPOSE

The purpose of this study was to evaluate the efficacy and safety of micropulse trans-scleral cyclophotocoagulation (MP-TSCPC) in PACG.

PATIENTS AND METHODS

Thirty-three phakic PACG eyes with patent laser peripheral iridotomy and IOP uncontrolled on maximum tolerable antiglaucoma medications (AGMs), scheduled for trabeculectomy, were given a trial of MP-TSCPC (810 nm laser, 2000 mw power for 180 seconds, 360 degrees). The primary outcome measure was a success at 1 year with IOP ≤18 mm Hg and ≤15 mm Hg with (qualified success) or without (absolute success) AGMs after a single session of MP laser. Secondary outcome measures were changes in pupillary diameter, visual acuity, central macular thickness, and subjective pain perception.

RESULTS

Thirty-two out of 33 PACG patients completed 12 months of follow-up. The mean age of patients was 54.7±8.9 years; male:female ratio was 1:1. The baseline IOP was 25.7±5.3 mm Hg, which reduced to 17.9±4.6 mm Hg at the end of 12 months (P<0.0001). Twenty eyes (62.5%) achieved qualified success, and 1 eye (3.125%) had absolute success at 12 months for IOP ≤18 mm Hg; 6 eyes (18.75%) had qualified success, and 1 eye (3.125%) had absolute success for IOP ≤15 mm Hg at 12 months follow-up. A significant reduction was also observed in the number of AGMs (4.4±0.8 at baseline to 2.9±1.1 at 12 months; P <0.0001). Five eyes (15.6%) received additional treatment-3 eyes (9.4%) requiring a subsequent filtering procedure, and 2 eyes (6.2%) requiring an additional MP-TSCPC session. No significant change in pupillary diameter (P=0.489) or central macular thickness (P=0.938) was noted at 12 months. There was a transient drop of visual acuity >2 lines in 1 patient due to cystoid macular edema, and no major postlaser complications were noted.

CONCLUSIONS

MP-TSCPC can be used as an interim procedure to reduce IOP in PACG eyes and delay the need for invasive surgery. Most patients require continued use of glaucoma medications, and target IOPs achieved are in the high teens.

Magnetic resonance imaging reveals possible cause of diplopia after Baerveldt glaucoma implantation

Purpose

To assess if ocular motility impairment, and the ensuing diplopia, after Baerveldt Glaucoma device (BGI) implantation, is related to the presence of a large fluid reservoir (bleb), using Magnetic Resonance Imaging (MRI).

Methods

In a masked observational study (CCMO-registry number: NL65633.058.18), the eyes of 30 glaucoma patients with (n = 12) or without diplopia (n = 18) who had previously undergone BGI implantation were scanned with a 7 Tesla MRI-scanner. The substructures of the BGI-complex, including both blebs and plate, were segmented in 3D. Primary outcomes were a comparison of volume and height of the BGI-complex between patients with and without diplopia. Comparisons were performed by using an unpaired t-test, Fisher’s Exact or Mann-Whitney test. Correlations were determined by using Spearman correlation.

Results

The median volume and height of the BGI-complex was significantly higher in patients with compared to patients without diplopia (p = 0.007 and p = 0.025, respectively). Six patients had an excessively large total bleb volume (median of 1736.5mm³, interquartile range 1486.3–1933.9mm³), four of whom experienced diplopia (33% of the diplopia patients). Fibrotic strands through the BGI plate, intended to limit the height of the bleb, could be visualized but were not related to diplopia (75% versus 88%; p = 0.28).

Conclusions

With MRI, we show that in a significant number of diplopia cases a large bleb is present in the orbit. Given the large volume of these blebs, they are a likely explanation of the development of diplopia in at least some of the patients with diplopia after BGI implantation. Additionally, the MR-images confirm the presence of fibrotic strands. As these strands are also visible in patients with a large bleb, they are apparently not sufficient to restrict the bleb height.

Ocular motility changes and diplopia in sutured versus unsutured implantation of the Baerveldt glaucoma device

Purpose

To investigate the effect of two surgical techniques in primary Baerveldt glaucoma implant (BGI) surgery, that is the sutured technique and the unsutured (free) plate technique, on the ocular motility and prevalence of diplopia. We hypothesize that the free plate technique results in a lower diplopia prevalence.

Methods

We performed a prospective study of patients who underwent BGI surgery with the free plate technique and compared them with patients from a previous study who had undergone BGI surgery with the sutured technique. Their ductions, ocular alignment and fusion range and the prevalence of diplopia were measured before surgery and at 3 months, 6 months and 1 year postoperatively.

Results

We analysed 57 free plate and 51 sutured plate patients. One year postoperatively, we found no statistically significant difference in the prevalence of diplopia between the two techniques. All duction changes between baseline and 1‐year follow‐up were restrictions and occurred statistically significantly more frequently in the free plate than in the sutured plate group (p = 0.03; 60% versus 34%). About the ocular alignment, in the horizontal direction, a change in exodirection was more common in both groups, while in the vertical direction, a hyperdeviation of the operated eye was more common. The vertical ocular alignment change was smaller in the free plate group than in the sutured plate group (p = 0.04 at near and p = 0.02 at distance).

Conclusions

One year postoperatively, the prevalence of diplopia was not significantly different between patients with the sutured plate and patients with the free plate technique. Both surgical techniques induce diplopia and changes in ocular motility and/or in ocular alignment.

Rates of Diplopia in Ahmed FP7, Baerveldt 250, and 350 Glaucoma Patients Compared With Medical Controls

PRECIS

Diplopia was present in ~20% of patients with Ahmed FP7 (FP7) or Baerveldt 350 (B350), compared with 5% to 6% in those with Baerveldt 250 (B250) or controls, suggesting risk of diplopia should be included in preoperative counseling.

PURPOSE

The purpose of this study was to examine the prevalence of diplopia and strabismus in patients with B250, B350, or FP7 glaucoma drainage devices (GDD).

MATERIALS AND METHODS

In this cohort study, glaucoma patients 18 years and above who had received, or would be receiving, a B250, B350, or FP7 GDD, and medically treated controls were consecutively enrolled from August 8, 2017, through July 31, 2019. The Diplopia Questionnaire was administered ≥30 days postoperatively, and upon enrollment to the controls. All diplopic patients underwent orthoptic measurements, which were reviewed by a strabismus specialist. Patients with GDDs in quadrants other than superotemporal, multiple GDDs, or scleral buckles were excluded. Bonferroni correction was applied for pairwise comparisons.

RESULTS

Diplopia was reported in 23/129 (17.8%) GDD patients and 5/99 (5.1%) control patients (P=0.003): 8/35 (22.9%) FP7, 2/32 (6.3%) B250, and 13/62 (21.0%) B350, with significant differences between FP7 versus controls (P=0.014) and B350 versus controls (P=0.011). Diplopia was attributable to GDD in 2 FP7 (5.9%, 95% confidence interval: 0.7-19.2), 0 B250, and 4 B350 (6.5%, 95% confidence interval: 1.7-15.2) patients, without significant differences between the GDDs.

CONCLUSIONS

Patients with the larger (B350) or the higher profile plate (FP7) GDDs were more likely to experience diplopia than controls, and diplopia was attributable to the GDD in ~6% of patients with either a FP7 or a B350 GDD. Since diplopia can affect patients' quality of life, preoperative counseling for GDD surgery, particularly B350 and FP7, should include a discussion of the risk of diplopia.

Orbital anatomy magnetic resonance imaging in diplopic versus non-diplopic patients after glaucoma drainage device placement

PURPOSE

New-onset persistent diplopia has become a common complication after glaucoma drainage device (GDD) placement. Understanding the orbital anatomy of such patients may provide information regarding risk of diplopia, GDD selection, and post-operative management. The purpose of this study was to examine the orbital anatomic differences in diplopic and non-diplopic patients after GDD implantation using high-resolution MRI.

METHODS

Seven eyes (N = 4 with diplopia and N = 3 without diplopia after GDD placement) of seven patients that had undergone placement of Baerveldt 250 (B250), Baerveldt 350 (B350), or Ahmed FP7 (FP7) GDD were prospectively enrolled at a single institution. All patients underwent a 3.0T orbital MRI with 3D volumetric T1 and T2 weighted sequence. Images were analyzed for orbital volume, axial length, orbital distances, presence of superior rectus-lateral rectus (SR-LR) band, position of GDD, and SR-LR angles.

RESULTS

Patients with diplopia had smaller mean ± SD orbital axial (911.5 ± 111.8 mm³ vs 931.7 ± 79.7 mm³) and coronal volumes (1162.5 ± 145.5 mm³ vs 1180 ± 34.6 mm³) compared to non-diplopic patients. Average orbital rim distances were larger for the diplopic group. The SR-LR displacement angle for diplopic patients was larger (101.6° ± 8.1 vs 94.7° ± 17.6) while the SR-LR quadrantic angle (86.6° ± 4.2 vs 89.1° ± 4.3) was smaller. SR-LR band was present and intact in all patients. GDD malpositioning was not evident in any patient.

CONCLUSION

The decreased orbital axial and coronal volumes as well as increased orbital rim distances in diplopic patients suggests the need for further studies to understand the role of orbital anatomy in occurrence of diplopia. Dynamic MRI imaging may be helpful in identifying differences in extraocular muscle function that reveal an etiology of diplopia in patients with GDD implantation.

Retrobulbar tube shunt: anterior chamber to back of the eye (A2B) efficacy in glaucomatous eyes with uncontrolled IOP

PURPOSE

The purpose of this study is to examine the efficacy and safety of a commercial model of the retrobulbar shunt, anterior chamber to back of the eye (A2B), in lowering intraocular pressure (IOP) and medication requirements after the failure of all other IOP-lowering therapies, including trabeculectomy with antimetabolites and tube shunt procedures.

METHODS

This is a single-site, prospective, nonrandomized concept study. Patients with prior failed tube shunts, or moderate to severe glaucoma refractory to treatment, were included. All subjects underwent A2B shunt implantation. Each subject's IOP and number of medications were assessed from baseline at each time interval using paired t tests. Primary outcome measures were IOP and glaucoma medication use pre- and postoperatively. Complete success is defined as (1) IOP ≤ 21 mmHg; (2) IOP reduction from baseline of ≥ 20%; (3) no reoperation for glaucoma; (4) no loss of light perception vision; (5) no chronic hypotony defined as IOP ≤ 5 mmHg; and (6) no use of supplemental glaucoma medication. "Qualified success" required satisfaction of the same criteria as "complete success" but with the use of supplemental glaucoma medication at 6 months.

RESULTS

Nineteen eyes of 19 patients (mean age 39.5 ± 6.4) were followed for 6 months. The mean IOP (mmHg±SEM) at 6 months dropped from baseline of 35.3 ± 2.3 to 18.5 ± 1.1(- 16.8, - 47%; p < 0.0001). The mean number of glaucoma medications (±SEM) at 30, 90, and 180 days decreased from a baseline of 2.4 ± 0.3 to < 0.3 at each interval (p < 0.0002). The complete and qualified success rates at 6 months were 46.6% (7/15) and 66.6% (11/15), respectively. The mean number of prior incisional glaucoma surgeries was 3.2. The percent of patients that had previously failed sub-Tenon tube shunt surgeries was 79%.

CONCLUSIONS

The A2B shunt is an effective rescue therapy in patients that have failed other IOP-lowering procedures. By shunting aqueous humor into the retrobulbar space, IOP and number of glaucoma medications required were substantially reduced for the 6-month postoperative assessment interval. The intrinsic properties of the retrobulbar space may limit the risk of fibrosis, the principal cause of bleb failure.

Removal of a Baerveldt Glaucoma Implant and Fibrous Adhesion for Refractory Mechanical Strabismus

Although strabismus is a well-known complication of glaucoma implant surgery, its surgical treatment is still challenging. We present a case with refractory strabismus after Baerveldt glaucoma implant (BGI) surgery, which was not sufficiently improved by strabismus surgery, but by removal of the BGI and fibrous adhesion. The patient was a 35-year-old woman who had multiple surgeries for secondary glaucoma. She had severe limitations of the movement of her right eye and binocular diplopia in all gaze positions after BGI surgery. Although she underwent two strabismus surgeries, the strabismus was not resolved. The surgery was performed by two specialists in glaucoma and strabismus. The BGI plate and the fibrous capsule were carefully removed. The fibrous tissue involved the muscle bellies of the inferior and particularly lateral rectus (LR) muscles and induced tight and wide adhesion between the muscle bellies and sclera. The adhesion was released after tenotomy at the insertion of the LR muscle, and the LR muscle was additionally resected by 6.0 mm. The ocular position and movement dramatically improved; however, intraocular pressure (IOP) increased immediately after the surgery. Then, Ahmed glaucoma valve implantation was performed 5 days after BGI removal. The IOP decreased and has been controlled. The improvement of ocular position and movement remained 9 months postoperatively and she obtained cosmetic satisfaction without diplopia or worsening of visual acuity. Removal of BGI and fibrous adhesion is a potential option for refractory mechanical strabismus following BGI surgery; however, it is important to prepare additional procedures for the subsequent IOP increase in advance.

Comparative Outcomes of the Molteno3 and Baerveldt Glaucoma Implants

PURPOSE

To compare outcomes between 2 nonvalved glaucoma drainage devices (GDDs) used to treat refractory glaucoma or in patients with neovascular/uveitic glaucoma likely to be poorly responsive to less aggressive therapies.

DESIGN

Retrospective, nonrandomized, multicenter comparative study.

PARTICIPANTS

A total of 117 eyes from 117 patients.

METHODS

Retrospective chart review of patients who underwent implantation of the Baerveldt (BGI) (Abbott Medical Optics, Abbott Park, IL) or the Molteno3 glaucoma implant (MGI) (Molteno Ophthalmic Limited, Dunedin, New Zealand). Noninferiority of the MGI versus the BGI was tested with Cox and mixed-effects regression models. Interventions in each group were analyzed with chi-square tests.

MAIN OUTCOME MEASURES

The primary outcome was time until device failure, defined as intraocular pressure (IOP) >21 mmHg or a reduction <20%, hypotony, reoperation for glaucoma, or loss of light perception. Secondary outcomes were intraoperative time, postoperative IOP, number of IOP-lowering medications, and visual acuity (VA).

RESULTS

The MGI could not be deemed noninferior to the BGI with regard to time until device failure (hazard ratio [HR], 0.83; confidence interval [CI], 0.41-1.65). The MGI was noninferior to the BGI when comparing postoperative IOP, a difference of -0.40 mmHg (95% CI, -1.74-0.93). The MGI needed 2% fewer medications (ratio of 0.98, 95% CI, 0.79-1.22), but noninferiority could not be claimed. With regard to VA, the MGI's mean was 0.10 logarithm of the minimum angle of resolution (logMAR) higher (95% CI, -0.01-0.21), but noninferiority testing was again inconclusive. Intraoperative time for the MGI was 15.7 minutes shorter versus the 350 mm² plate size BGI (P < 0.001) and 4.3 minutes shorter versus the 250 mm² plate size BGI (P = 0.32). More patients in the MGI group needed secondary operative management (11%, P = 0.03).

CONCLUSIONS

The MGI was noninferior to the BGI in lowering IOP. Differences in time until device failure, VA outcomes, and medication use were inconclusive. The MGI required more secondary operative interventions. The MGI required less time to implant than the BGI's 350 mm² plate size implant. Overall, the use of both GDDs is justifiable to lower IOP when more conservative management has failed.

Primary baerveldt versus trabeculectomy study after 5 years of follow-up

PURPOSE

Although the Baerveldt glaucoma implant (BGI) initially was reserved for refractory glaucoma, its role in the surgical management of glaucoma has shifted towards a primary treatment choice. We performed a randomized prospective study to compare BGI surgery and trabeculectomy (TE) in patients without previous ocular surgery.

METHODS

We included 119 glaucoma patients without previous ocular surgery. One eye of each subject was randomized to either a BGI or TE. Follow-up visits were at 1 day, 2 weeks, 6 weeks, 3 months, 6 months and 1, 2, 3, 4 and 5 years postoperatively. Primary outcomes were intraocular pressure (IOP) and failure rate. Secondary outcomes were medication, anterior chamber laser flare value and complications.

RESULTS

After 5 years, an IOP of 12.7 ± 3.9 mmHg (mean ± SD) was achieved in the TE group and 12.9 ± 3.9 mmHg in the BGI group. We found no statistically significant difference in failure rate between the groups (p = 0.72). More BGI patients needed additional medication to control their IOP (85%; 1.9 ± 1.2 types of glaucoma medication) compared to the TE patients (57%; 0.5 ± 0.9 types of glaucoma medication). Diplopia was significantly more present in the BGI group than in the TE group (27% versus 4%; p < 0.001). The self-limiting complication rate was similar in both groups.

CONCLUSIONS

Our study demonstrates that, in the long term, the final IOP and failure rate are similar after TE and BGI surgery. However, the need for additional medication after BGI surgery is higher than after TE. Also, the increased risk of developing diplopia after BGI surgery must be taken into consideration.