Repair Of Blebs Research Articles

Safety and Efficacy of the Preserflo® Microshunt in Refractory Glaucoma: A One-Year Study.

Purpose: To evaluate the safety and efficacy of Preserflo® microshunt implantation in eyes with refractory glaucoma. Methods: In this retrospective study, a cohort of patients who underwent Preserflo® microshunt implantation between April 2019 and August 2020 for refractory glaucoma were evaluated. At the time of surgery, all eyes had uncontrolled intraocular pressure (IOP) despite maximally tolerated medical therapy and at least one previous failed glaucoma filtering surgery. The primary outcome was a complete success, defined as postoperative IOP ≤ 21 mm Hg with an IOP reduction ≥ 20% and no repeat filtering surgery. The secondary outcome was qualified success, defined as a complete success with the use of antiglaucoma medications. The rates of needling, bleb repair, and postoperative complications were also recorded. Results: Forty-seven eyes with a mean preoperative IOP of 30.1 ± 7.1 mm Hg and a mean of 3.4 ± 1 glaucoma medications were included. The mean number of previous surgeries prior to microshunt implantation was 2.3 ± 1.3. After 1 year, the mean IOP was significantly reduced to 18.8 ± 4.6 mm Hg, with the mean number of medications significantly reduced to 1.4 ± 1.2. Complete success was achieved in 35% of eyes, and a qualified success in 60% of eyes. A decrease in IOP of at least 30% was found in 55% of eyes. Needling or bleb repair was performed in 49% of eyes. Complications were minimal and transient, except for one eye which presented with tube extrusion, and another eye with a transected tube. A repeat glaucoma surgery had to be performed in 17% of eyes. Conclusions: The Preserflo® Microshunt provided moderate success but a significant reduction in IOP, with a good safety profile after one year of follow-up in eyes at high risk for failure of filtering surgery.

Spontaneous Pneumothorax: A Rare Complication of Neurofibromatosis Type 1 Associated Diffuse Lung Disease

The visually striking neurocutaneous findings of neurofibromatosis type 1 (NF1) are well recognized and have been well documented throughout scientific literature. While not uncommon, the pulmonary manifestations of NF1 are unknown to many physicians. Complications of NF1 associated diffuse lung disease (NF-DLD) include pulmonary hypertension, pulmonary artery stenosis, subpleural cysts, and spontaneous pneumothorax. We present a case of a 34-year-old male with NF-DLD found incidentally in adolescence with previous apical bleb repair, presenting nearly twenty years later with spontaneous pneumothorax. In NF1 patients with pulmonary complaints, NF-DLD should be assessed with computed tomography (CT) and physicians should be familiar with associated complications.

Bleb revision with bleborhexis and clear corneal lamellar patch graft for overhanging cystic bleb.

Background:Trabeculectomy is associated with several complications. One of the common complications with mitomycin assisted trabeculectomy is thin cystic bleb leading to bleb leak, hypotony and infections. Various technique of bleb repair and reconstruction have been described, such as conjunctival advancement, or scleral, pericardial or corneal patch graft.Purpose:To demonstrate bleb revision by bleborhexis and clear corneal lamellar patch graft for a patient with thin cystic leaking bleb leading to hypotony and decreased vision.Synopsis:This was a 75-year-old one-eyed lady, diagnosed with primary angle-closure glaucoma in both eyes with absent light perception in the left eye, had undergone a combined trabeculectomy and cataract surgery in the right eye 6 years ago. She presented with diminution of vision (6/18p), introacular pressure (IOP) of of 6 mmHg, thin cystic leaking overhanging bleb, and dysesthesia. Bleb repair by bleborhexis with lamellar corneal patch graft was performed. Bleborhexis is a technique in which the overhanging fibrosed thin cystic conjunctival bleb is peeled off the cornea smoothly to leave a uniform clear corneal surface. Clear cornea, uniform diffuse bleb, well-formed anterior chamber with and IOP of 15 mmHg was noted on the first post-operative day, with a vision of 6/12p. This procedure helped meticulous reconstruction of the bleb, early recovery of vision, maintanance of normotensive eye, and save the eye from potential infections.Highlights:Bleborhexis with lamellar corneal patch graft provides for an easy and a elegant surgical technique with minimal corneal tissue damage, faster healing and patient comfort. It could be the favored technique in patients with thin overhanging clebs.Video link: https://youtu.be/GeFYHWToueU

Intraoperative Optical Coherence Tomography-Guided Bleb-sparing Epithelial Exchange: A Modified Approach.

With the advent of newer technologies, real-time anterior segment optical coherence tomography (OCT) integrated with the operating microscope has become possible. We are proposing the technique of bleb revision with greater precision under direct visualization of bleb anatomy and extent of tissue depth allowing better localization and easy maneuvering with lesser complications. In this surgical technique, bleb revision was performed using intraoperative real-time OCT incorporated in OPMI LUMERA 700 microscope. Live surgical and OCT view were seen on a common screen together. A moderately elevated, diffuse functional bleb was noted after three months of bleb revision in both cases with controlled intraocular pressure. Intraoperative OCT-guided bleb-sparing epithelial exchange is an adjunctive technique for bleb repair surgery with an increased precision of surgery which can reduce complications, minimize surgical time and maximize surgical outcome.

Ologen collagen matrix for bleb repair in long standing sweating bleb- A case report with histopathological correlation

A 68-year-old man, presented with reduced vision and hypotony 6 years after combined cataract + glaucoma (phacoemulsification + trabeculectomy + intraocular lens) surgery with Mitomycin-C, clinical evaluation depicted a sweating bleb. Surgical repair was done with the use of donor scleral patch graft and collagen matrix implant along with conjunctival advancement. Histopathology of the excised thinned-out bleb wall showed a single layer of metaplastic conjunctival epithelium with the complete absence of goblet cells. The use of adjuvant mitomycin-C in trabeculectomy is known to cause bleb leak and associated complications in the long run. However, the histopathological features of sweating blebs and their surgical management is not well defined in the literature.

Pericardium Patch Graft (Tutoplast) for Bleb Repair and Bleb Remodelling After Nonpenetrating Filtering Surgery: 6-Month Outcomes.

The purpose of this study was to evaluate the outcome of pericardium patch graft (Tutoplast) as an adjuvant to either bleb repair or bleb reduction after nonpenetrating filtering surgery. Retrospective study, at a tertiary glaucoma center. Bleb revision with Tutoplast positioning was performed either for bleb repair to treat early leaks or hypotony with maculopathy, either for bleb reduction to improve ocular pain, discomfort, burning, foreign body sensation, tearing, and fluctuations of visual acuity. Intraocular pressure (IOP), best corrected visual acuity, number of antiglaucoma medications, and postoperative complications were analyzed postoperatively at 1 week, 1, 3, 6 months, and compared with the preoperative baseline. Surgical success was defined as achieving an IOP between 8 and 16 mm Hg. Six-month data were available from 15 eyes of 15 patients; mean patient age was 69.6±11.7 (66.7% male). Bleb revision was necessary for 10 patients due to bleb dysesthesia (bleb reduction), and in 5 patients due to leaking filtering bleb (bleb repair). The success rate was 73.3% at 6 months, with a significant IOP increase from 4.9±2.2 mm Hg preoperatively to 12.7±3.5 mm Hg at 6 months (P=0.0001), and a concomitant rise of best corrected visual acuity from 0.5±0.3 to 0.6±0.3 (P=0.2871). To control IOP, antiglaucoma medications were needed for 3 patients (20%) at 6 months. Overall, 3 patients (20%) required additional bleb revision for persistent hypotony, and 1 patient underwent a subsequent glaucoma surgery (transscleral cyclodestruction). Pericardium patch graft (Tutoplast) is a safe and effective adjuvant for bleb revision due to bleb dysesthesia of leaking filtering bleb after nonpenetrating filtering surgery.

Outcomes of Bleb Repair for Delayed Bleb Leaks and Sweating Blebs.

To report the outcomes of bleb repair for delayed onset leaking blebs and sweating blebs following glaucoma filtering surgery. Medical records of 76 eyes of 76 subjects that underwent bleb repair for either leaking bleb or sweating bleb between 1990 and 2015 were reviewed. Complete success was resolution of bleb leak and or hypotony with intraocular pressure ≥5 and ≤21 mm Hg with no antiglaucoma medication. There were 45 eyes with leaking bleb and 31 eyes with sweating bleb that underwent bleb repair by either conjunctival autograft or conjunctival advancement (P=0.11). Before bleb repair, complications like blebitis and hypotony maculopathy were significantly higher in sweating bleb group (13/31) compared with bleb leak group (5/45) (P=0.002). Median follow-up after bleb repair was >2 years in both groups (P=0.69). After repair, eyes in leaking bleb group had higher immediate (P=0.01) and long-term intraocular pressure elevation (P=0.06) compared with sweating bleb group. Complete success probability in sweating bleb group was significantly better (88%, 78%, and 71%) compared with leaking bleb group (54%, 45%, and 40%) at 1, 3, and 6 years, respectively (P=0.01). One eye in each group had blebitis, 2 eyes in leaking bleb group and 1 eye in sweating bleb group needed repeat glaucoma intervention. Higher complication rate before bleb repair in eyes with sweating bleb warrants early bleb repair. Bleb repair helped retain bleb function in majority of the eyes with sweating blebs, strengthening our recommendation.

Amniotic membrane in ophthalmology: A versatile wonder

Amniotic membrane is a unique biological product that has been in use for a myriad of bodily conditions, both ophthalmic and non-ophthalmic. However, the ophthalmic use are still increasing day by day. Its unique properties like anti-inflammatory, antimicrobial, antifibrotic, antiangiogenic and source of growth factors make it into a biological bandage which can be life-saving to the eye. Harvested from the human placenta, it has found extensive use in ocular surface reconstruction, chemical injury to the eye, corneal perforation, persistent epithelial defects, ocular surface neoplasia, pterygium surgery, trabeculectomy, glaucoma bleb repair and lid surgeries, to name a few. This article outlines in detail the properties and utility of amniotic membrane.

Outcomes of Bleb Excision With Free Autologous Conjunctival Patch Grafting for Bleb Leak and Hypotony After Glaucoma Filtering Surgery

To determine the outcomes of bleb excision with free autologous conjunctival patch grafting for bleb leak and hypotony after glaucoma filtering surgery. Retrospective, consecutive, noncomparative case series. Outcome measures were closure of bleb leak, intraocular pressure (IOP), and best corrected visual acuity after patch grafting and complications from intervention. Complete success was defined as resolution of the bleb leak or hypotony, with IOP between 6 and 18 mm Hg. Fifty-eight eyes (57 patients) were included: 51 with bleb leaks and 7 with hypotonous maculopathy without a bleb leak. Eight eyes required scleral flap resuturing and 2 required scleral patch grafts in addition to free conjunctival patch grafting. The mean postoperative follow-up period was 112.65 ± 128.74 weeks (median 80.0 wk). At 6 weeks and final follow-up, the IOP increased from baseline of 4.41 ± 4.61 mm Hg (median 4.00 mm Hg) to 11.98 ± 6.25 mm Hg (median 11.50 mm Hg) (P<0.001) and 12.67 ± 4.83 mm Hg (median 12.00) (P<0.001), respectively. Visual acuity increased from baseline of 0.87 ± 0.95 logMAR (median 0.60) to 0.65 ± 0.80 logMAR (median 0.48) (P=0.001) and 0.76 ± 0.93 logMAR (median 0.48) (P=0.35) at 6 weeks and last follow-up, respectively. The complete and qualified success rates at the final follow-up were 75.8% and 79.3%, respectively. Failure events occurred in 12 (20.6%) eyes, including 2 eyes with hypotony, 5 with raised IOP, and 3 with postoperative bleb leaks. Free conjunctival patch grafting is a successful procedure for bleb repair and hypotony providing moderate IOP control with minimal postoperative complications in majority of patients.

Buccal Mucous Membrane for the Reconstruction of Complicated Leaking Trabeculectomy Blebs

Late onset trabeculectomy bleb leaks often require surgical repair to avoid hypotony and/or infection. Repair using local conjunctiva is typically performed. However, in cases in which local conjunctiva is limited and/or has failed, buccal mucous membrane can be used as a conjunctival substitute. Four cases of buccal mucous membrane repair for leaking trabeculectomy blebs are reported. Surgical technique is described. In each case of bleb leak, multiple nonincisional techniques failed to control the leak. In 3 of 4 cases, earlier reconstruction attempts with conjunctival advancement and/or free flaps failed. Each was ultimately repaired with buccal membrane autograft. One case required additional minimally invasive procedures to control postoperative leaking. One case required a second adjacent buccal graft for leaking residual conjunctival bleb. Each graft was functioning well at most recent follow-up ranging from 1 to 17 months. Buccal membrane is an abundant and effective conjunctival substitute for the repair of recalcitrant leaking trabeculectomy blebs. It may be useful in cases in which earlier conjunctival-based repairs have failed.

Surgical revision of dysfunctional filtration blebs with bleb preservation, sliding conjunctival flap and fibrin glue

The introduction of anti-metabolite regimens to glaucoma filtration surgery has improved post-operative intraocular pressure (IOP) control; however, it has also increased the frequency of dysfunctional blebs. In this study, we report a surgical technique for the repair of trabeculectomy blebs using bleb preservation, a sliding conjunctival flap, and fibrin glue. This study is a retrospective, non-comparative, consecutive case series involving 10 eye samples collected from 10 patients (6 M : 4 F) with one or a combination of bleb overfiltration, dysesthesia, thinning, leak, or blebitis, in which a conjunctival flap was advanced over the failing bleb and secured in place using fibrin glue and sutures. All patient eyes had symptom resolution post-operatively. There were no bleb leaks or hypotonous eyes after an average follow-up of 15.2 months (range: 6-31 months). Three patients required needling augmented with 5-fluorouracil needling to maintain IOP control. IOP decreased from a mean of 13.6+/-1.8 mm Hg (with a mean of 0.7 glaucoma medications) pre-operatively to 11.7+/-0.9 mm Hg (with a mean of 0.9 glaucoma medications). Conjunctival flap advancement with bleb preservation and adjunctive fibrin glue is a successful technique used for the treatment of bleb dysfunction. The major advantages compared with other techniques are preservation of IOP control and reduced post-operative complications, such as wound leak and the need for re-suturing.

Combined Conjunctival Relieving Incisions and Advancement for the Repair of Late-onset Leaking Trabeculectomy Blebs

To describe a surgical technique for the repair of late-onset leaking blebs. A surgical technique is described followed by a retrospective review of 5 clinical cases. All patients had a minimum of 12 months follow up. In all cases the leaks were successfully closed and bleb function was maintained. Of 5 patients, 3 required subsequent topical glaucoma medication though none required further drainage surgery. The mean intraocular pressure at last follow up was 16 mm Hg (range 10 to 27 mm Hg). This technique can be considered as an option for patients who require surgical revision for a leaking trabeculectomy bleb.

Histopathologic Features of Conjunctival Filtering Blebs

To characterize and compare the histological features of conjunctiva obtained during the repair of trabeculectomy and inadvertent blebs and to assess the effects of antifibrotic agents. We used routine paraffin processing and light microscopy to examine conjunctival specimens from 28 eyes undergoing late bleb revision: 19 leaking trabeculectomy blebs, 5 nonleaking trabeculectomy blebs, and 4 inadvertent blebs. Quantitative analysis of histological characteristics included conjunctival epithelial thickness, stromal vascularity, squamous metaplasia, stromal inflammatory cell infiltrate, and goblet cell density. The type of surgery, presence of leaks, prior topical medication, and antifibrotic use were correlated with histological findings. Trabeculectomy blebs (leaking and nonleaking) showed decreases in overall epithelial thickness (P<.02), goblet cell density (P<.001), and vascularity (P<.001) compared with inadvertent bleb controls. Conjunctiva exposed to antifibrotics had fewer layers of epithelial cells than those with no prior exposure (P<.05). Histological analysis of thin blebs excised following trabeculectomy demonstrated decreases in epithelial thickness and goblet cell density compared with inadvertent blebs. Both leaking and nonleaking trabeculectomy blebs exhibited decreases in localized stromal vascularity and increases in surrounding stromal vascularity compared with normal conjunctiva.

Free conjunctival autologous graft for bleb repair and bleb reduction after trabeculectomy and nonpenetrating filtering surgery.

To describe methods and outcomes of excisional revision of a filtering bleb (bleb revision) using free conjunctival autologous graft either for bleb repair or for bleb reduction after trabeculectomy and deep sclerectomy with an implant. Retrospective medical records were reviewed for a consecutive non-comparative case series comprising patients who underwent excisional revision of a filtering bleb between May 1998-January 2001. Excisional revision using free conjunctival autologous graft (bleb revision) was performed either for bleb repair, to treat early and late leaks and hypotony with maculopathy, or for bleb reduction, to improve ocular pain, discomfort, burning, foreign body sensation, tearing, and fluctuations of visual acuity. The revision consisted of bleb excision and free conjunctival autologous graft. The bleb histopathology was analyzed in patients who underwent bleb repair. Sixteen patients were included in the study, consisting of nine patients who had a trabeculectomy and seven patients who had a deep sclerectomy with an implant. Bleb revision was necessary in 14 patients due to leaking filtering bleb (bleb repair), and in 2 patients due to bleb dysesthesia (bleb reduction). After a follow-up of 15.1 +/- 8.4 months, the mean intraocular pressure (IOP) rose from 7.8 +/- 6.3 mm Hg to 14.3 +/- 6.5 mm Hg, and the visual acuity from 0.4 +/- 0.3 to 0.7 +/- 0.3, with a P value of 0.008 and 0.03, respectively. The complete success rate at 32 months, according to the Kaplan-Meier survival curve, was 38.3%, and the qualified success rate was 83.3%. Four patients (25%) required additional suturing for persistent bleb leak. To control IOP, antiglaucoma medical therapy was needed for six patients (37.5%) and repeated glaucoma surgery was needed for one patient. Free conjunctival autologous graft is a safe and successful procedure for bleb repair and bleb reduction. However, patients should be aware of the postoperative possibility of requiring medical or surgical intervention for IOP control after revision.

Bleb reduction and bleb repair after trabeculectomy

Objective To describe methods and outcomes for repair of bleb-related complications of trabeculectomy surgery. Design Retrospective, consecutive, noncomparative case series. Participants Thirty-one persons having bleb revision by two surgeons at the Wilmer Institute from 1994 to the present. Intervention One of two types of revision surgery was performed: bleb reduction to decrease symptoms from large blebs or bleb repair to improve hypotony, using conjunctival rotation flap or free conjunctival autograft. Main outcome measures Visual acuity, intraocular pressure (IOP), reported symptoms, complications, and number of glaucoma medications at the final visit. Results The mean time from trabeculectomy to bleb revision was 4.4 years. Bleb reduction was performed because of symptomatic, high blebs in 11 eyes of 11 persons. Bleb repair was performed to end bleb leakage in 13 eyes of 13 persons and to increase IOP in 8 eyes of 7 persons with hypotony. Median visual acuity improved from 20/50 before revision to 20/30 at most recent follow-up. Mean IOP increased after treatment from 7.7 ± 4.9 to 12.4 ± 4.0 mmHg ( P < 0.001). Symptoms that caused the revision surgery were eliminated in all cases. None of these eyes has lost IOP control, none has required repeat trabeculectomy, and only 2 of the 32 (6%) require topical glaucoma medication. More than one revision procedure was required in 8 of 32 (25%) eyes. Conclusions Surgical bleb revisions for complications after trabeculectomy surgery are safe and effective. Bleb reduction for large, symptomatic blebs or bleb repair for leaking blebs and hypotony did not lead to loss of IOP control.

Reconstruction of Filtering Blebs with Free Conjunctival Autografts

Situations arise in which the surgical repair or revision of filtering blebs is either technically impossible or inadequate, and total reconstruction becomes necessary. This is most frequently encountered in eyes that have undergone multiple procedures, resulting in significant bulbar conjunctival scarring and episcleral fibrosis. To preserve the pre-existing filtration site, the authors successfully treated five such patients in whom conjunctival scarring adjacent to and surrounding the blebs precluded local revision, by transplanting free conjunctival autografts. Two patients required grafting from the fellow eye. Specific modifications from previously reported conjunctival flap techniques were used to enhance graft healing and continued filtration. Satisfactory intraocular pressure control was maintained in all patients receiving minimal to no anti-glaucomatous medications with an average follow-up of 42.6 months (range, 7-90 months). No patient had a significant decrease in visual acuity or surgical complications. Free conjunctival autografting techniques are a useful adjunct in the surgical revision of leaking, failed, or migrating filtration blebs.

Electropulsing of acinar cells isolated from rat pancreas: Studies of reversible membrane perforation and blebbing

Electropulsing of pancreas cells was performed by the charge pulse technique. Injury to the cells and their repair were determined by means of trypan blue exclusion. The voltage and the capacitance were selected such that membrane perforation and membrane deformation (as blebs) in standard cells (cells with a survival rate in excess of 92% after 4 h) was reversible. Depending on the electrical conditions, the percentage of cells without membrane perforation one minute after electropulsing ranged from 15% to 62%, and the percentage of cells without membrane deformation ranged from 26% to 51%. Irrespective of the electrical parameters, repair of membrane perforation was complete after 15 min. In contrast, 30 min to 2 h were required for repair of blebs to finish. Identical investigations were conducted with injured cells. The percentages after electropulsing were higher than those for standard cells. No repair was observed. Injury and repair were found to also depend on the functionality of cells. Comparison between standard cells and the cells to be studied permits the functionality of such cells to be assessed.

Electropulsing of acinar cells isolated from rat pancreas: Studies of reversible membrane perforation and blebbing

Electropulsing of pancreas cells was performed by the charge pulse technique. Injury to the cells and their repair were determined by means of trypan blue exclusion. The voltage and the capacitance were selected such that membrane perforation and membrane deformation (as blebs) in standard cells (cells with a survival rate in excess of 92% after 4 h) was reversible. Depending on the electrical conditions, the percentage of cells without membrane perforation one minute after electropulsing ranged from 15% to 62%, and the percentage of cells without membrane deformation ranged from 26% to 51%. Irrespective of the electrical parameters, repair of membrane perforation was complete after 15 min. In contrast, 30 min to 2 h were required for repair of blebs to finish. Identical investigations were conducted with injured cells. The percentages after electropulsing were higher than those for standard cells. No repair was observed. Injury and repair were found to also depend on the functionality of cells. Comparison between standard cells and the cells to be studied permits the functionality of such cells to be assessed.

Repair of filtering blebs following cataract surgery.

In a consecutive series of 710 cataract extractions, unintentional postoperative filtering blebs occurred in 18 eyes. The incidence of filtering blebs after limbus based conjunctival flaps vs after fornix based conjunctival flaps was 7:1. Postoperative complications were the most common etiologic factor associated with the production of filtering blebs. Site of suture placement, incision site into the anterior chamber, use of enzymatic zonulolysis, or operative complications could not be correlated either with development, size, or location of blebs. Indications for operative bleb closure include foreign body sensation, tearing, persistent leakage of aqueous, interference with contact lens wear, and macular edema. The technique for repairing the unintentional filtering bleb has proven safe and effective.