Intracameral Air Research Articles

Does Same-Day Postoperative Increased Intraocular Pressure Affect Endothelial Cell Density After Descemet Membrane Endothelial Keratoplasty?

High intraocular pressure (IOP) is common in association with intracameral air and gas tamponade after Descemet membrane endothelial keratoplasty (DMEK); yet its influence on endothelial cell survival is unknown. Our aim was to determine the effect of high IOP measured 2 hours after DMEK on 1-month endothelial cell density (ECD). The influence of other potentially relevant factors was also investigated. Retrospective, consecutive series. Inclusions: low-to-moderate risk DMEK surgery alone or combined with phacoemulsification. previous penetrating keratoplasty or glaucoma surgery; grafts with any of the following in the first month: rebubble, rejection, or graft failure. Sixty-two grafts met inclusion with 60 having IOP recorded at 2 hours. Thirty-eight percent (23/60) had IOP >30 mm Hg and 22% (13/60) had IOP >40 mm Hg at 2 hours. All grafts with IOP >30 mm Hg had air released and immediate normalization of pressure. One-month ECD (mean ± standard error of mean) was 1872 ± 58 cells/mm, representing cell loss of 29.8 ± 2.0%. Two-hour IOP was highly insignificant against 1-month ECD when tested as a continuous variable (P = 0.78). Lower 1-month ECD was statistically correlated with lower donor count (P = 0.002) and combined DMEK-phaco surgery (P = 0.01) on univariate and multivariate analysis. Insignificant factors (P > 0.05) against 1-month ECD included patient age, sex and race, surgical indication (Fuchs endothelial dystrophy vs. non-Fuchs endothelial dystrophy), and donor age. Increased IOP at 2 hours is common after DMEK, but does not seem to influence early endothelial cell survival. One-month ECD was influenced by donor counts and combined cataract surgery.

Descemet's membrane endothelial keratoplasty: surgical outcomes and endothelial cell count modelling from a UK centre.

To report surgical outcomes and endothelial cell density (ECD) trends up to 2 years post-operatively in the first cohort of eyes undergoing Descemet's membrane endothelial keratoplasty (DMEK) for low-to-moderate risk indications at our UK centre. Tight corneal sutures were used to ensure high intraoperative pressure from intracameral air for 10-min and to maintain a good post-operative air fill. Outcomes were compared to a prior series at our unit of similar eyes having Descemet's stripping endothelial keratoplasty (DSEK). Retrospective, interventional series. Inclusions: all DMEKs with a minimum of 1-month follow-up. prior glaucoma surgery, penetrating keratoplasty or anterior chamber lens. 88 DMEKs met inclusion. Median follow-up: 332 days. Main indication: Fuchs dystrophy (90%). re-bubbling 2%, primary failure 6%, retinal detachment 2%, rejection 3%. At 3 months, BCVA ≥6/6 and ≥6/9 were 67% and 86%, respectively. Graft survival at both 1 and 2 years was 94 ± 2%. Mean(±SD) cell-loss at 1 month, 3 months, 6 months, 12 months and 24 months: 30 ± 15%, 29 ± 16%, 33 ± 17%, 35 ± 17% and 48 ± 16%, respectively. Compared to a prior series at our unit of 210 low-to-moderate risk DSEKs, cell loss was lower for DMEK at all time-points (p < 0.001) through to 12 months but was not statistically different at 24 months. Mixed-modelling of ECD over time demonstrated the convergence of DMEK and DSEK curves by 2 years. DMEK using tissue from UK eye-banks resulted in high survival and excellent visual acuity. ECD through 1 year was superior to DSEK in a similar cohort. Our low re-bubble rate (2%) may be attributable to use of intracameral air at temporarily elevated intraocular pressure.

Modeling Floppy Iris Syndrome and the Impact of Phenylephrine on Iris Buckling

Abnormal iris movement (floppy iris syndrome) during intraocular surgery is associated with an increased risk of intraoperative complications. We have previously investigated this scenario with respect to intracameral air in corneal endothelial transplantation, and described the concept of iris buckling. As a number of clinical interventions are recommended for addressing floppy iris syndrome, we wished to evaluate the impact of intracameral phenylephrine on iris buckling and so refine our mathematical model. We considered the stability of an iris structure under a uniform pressure loading. We performed mathematical and computational simulations to demonstrate iris buckling, and then altered the parameters to assess the impact of phenylephrine on the model. We elucidated a number of buckled iris configurations which become unstable as the intraocular pressure increased, for transversely isotropic iris material properties, and identified a positive correlation between the critical pressure and the iris stiffness. A mechanical analysis with a dilated pupil (mimicking phenylephrine use) was also conducted, and demonstrated a significant increase in the critical pressure required to induce iris buckling. We have shown that iris buckling can arise at lower pressures when the iris stiffness is reduced, as in floppy iris syndrome. The use of phenylephrine was shown to prevent iris movement (buckling) by increasing the required critical pressures. This refined model demonstrates the positive effectiveness of phenylephrine in the management of floppy iris syndrome and gives evidence to the clinical practice of using this as a preventative measure.

Descemet's membrane detachment following uneventful phacoemulsification surgeries: A case report.

Rationale:Descemet's membrane detachment (DMD) may occur during or following cataract surgery, causing corneal edema and visual loss1. The incidence of DMD after phacoemulsification surgery is only approximately 0.5%, and mostly surgical-related. Late onset bilateral spontaneous DMD after sequential uneventful cataract surgeries, is even rarer, and may result from not only surgery itself, but also from an underlying anatomic abnormality 2.Patient concerns:We present a 80 year old female developed bilateral descemet's membrane detachment after sequential uncomplicated cataract surgeries.Diagnosis:Bilateral Descemet's membrane detachment.Interventions:One eye (left eye) was treated with intracameral air injection and the fellow eye (right eye) was treated with medical treatment only.Outcomes:The DMDs were reattached in both eyes after treatment. Surgical intervention accelerated the duration of recovery and there were no significant outcome differences between the right and the left eye.Lessons:Even if there is a large area of DMD with visual axis involvement, conservative treatment with close observation might still provide a satisfactory result if Descemet's membrane is separated from the posterior corneal stroma by ≤1 mm.

Triple chamber: a clinical rarity after deep anterior lamellar keratoplasty and role of optical coherence tomography in management

To report a case demonstrating triple chamber following deep anterior lamellar keratoplasty (DALK) and its successful intra-operative optical coherence tomography-guided management. Case report of a young male with macular corneal dystrophy, who underwent DALK in his left eye by Big-Bubble technique. The surgery was uneventful. On the first post-operative day, triple chamber was observed and followed-up with serial clinical photography and anterior segment optical coherence tomography. Due to decrease in graft clarity and increase in volume of the two extra chambers, interface drainage along with descemetopexy was undertaken 4days later. The compartments constituting the triple chamber were those in-between the donor tissue and host pre-Descemet layer (Dua's layer), the latter and host Descemet membrane and the true anterior chamber. Presence of viscoelastic in the interface was identified as the cause. Microscope integrated optical coherence tomography (MiOCT) guided drainage followed by intracameral air tamponade ensured near total disappearance of the two extra chambers at the end of surgery. Examination on the next day confirmed complete apposition of the graft and host. To the best of our knowledge, this is a unique demonstration of Dua's layer in vivo by slit lamp biomicroscopy and description of MiOCT guided management of triple chamber.

An alternative technique for Descemet\u2019s membrane detachment following phacoemulsification: case report and review of literature

BackgroundDescemet’s membrane detachment (DMD) is one of the most serious complications of modern cataract surgery. We present an alternative technique for management of DMD with a review of the literature on current strategies for the treatment of DMD.Case presentationA 74-year-old woman developed DMD after phacoemulsification and failed the first descemetopexy with air tamponade. An alternative method was used to drain the pre-descematic fluid and reposition the detached Descemet’s membrane in this rare case. This technique involved completely filling the anterior chamber with an intracameral air injection, followed by using a 23-gauge needle to puncture the peripheral cornea to drain the pre-descematic fluid. The Descemet’s membrane was completely reattached to the stroma during the follow-up.ConclusionsDrainage of pre-descematic fluid combined with intracameral air tamponading was used as an alternative surgical option for the management of this severe case of DMD.

Surgical management of spontaneous, late-onset Descemet membrane detachment after penetrating keratoplasty for keratoconus: a case report

BackgroundTo report a surgical method for treating corneal oedema in a case of late-onset Descemet membrane detachment after penetrating keratoplasty.Case presentationA 55-year old patient presented with sudden visual loss in his left eye 28 years after penetrating keratoplasty for keratoconus. Slit-lamp biomicroscopy revealed a distortion of the corneal graft anatomy with protrusion of the graft and peripheral thinning and steepening in the residual host tissue, accompanied by corneal graft oedema. Anterior segment optical coherence tomography revealed detachment of Descemet membrane localized to the area of the graft oedema. We proceeded with a full-thickness, partially circumferential incision in the graft-host junction, followed by repositioning and re-suturing of the graft in place, and intracameral air injection in order to achieve reattachment of Descemet membrane.ConclusionsCorneal graft repositioning in combination with re-bubbling may represent an effective therapeutic option in keratoconic patients with peripheral thinning in the residual host corneal tissue and subsequent Descemet membrane detachment.

Rebubbling in Descemet Membrane Endothelial Keratoplasty: Influence of Pressure and Duration of the Intracameral Air Tamponade

To explore the impact of intracameral air tamponade pressure and duration on graft attachment and rebubbling rates. A prospective, interventional, nonrandomized study. setting: Department of Ophthalmology, Charité - Universitätsmedizin Berlin. One hundred seventeen patients who underwent Descemet membrane endothelial keratoplasty (DMEK). Intraocular pressure (IOP) at the end of the surgery, immediately after filling the anterior chamber with air, categorized into low (<10mm Hg), normal (10-20mm Hg), and high (>20mm Hg), and the time until partial removal of the air. Rebubbling rates and endothelial cell density over a 3-month follow-up period analyzed by a multivariable Cox regression model and an analysis of covariance model. Thirty-two patients required a rebubbling (27% [95% CI 19%-35%]). Nine patients required more than 1 rebubbling (7% [95% CI 3%-12%]). Compared with normal IOP, lower (HR 8.98 [95% CI 1.07-75.41]) and higher IOP (HR 10.63 [95% CI 1.44-78.27]) increased the risk of requiring a rebubbling (P= .006). Independent of the IOP, an air tamponade duration beyond 2 hours reduced the risk of rebubbling (HR 0.36 [95% CI 0.18-0.71, P= .003]). One month after surgery, the mean endothelial cell loss was 13% (95% CI 2%-25%) and 23% (95% CI 17%-29%) in the group with air tamponade duration of below and above 2 hours, respectively (P= .126). At 3months after surgery, it was 31% (95% CI 17%-42%) and 42% (95% CI 32%-52%) in the respective groups (P= .229). A postsurgical air tamponade of at least 2 hours with an IOP within the physiological range could help to reduce rebubbling rates.

Air bubble-induced intraocular lens opacification in hydrophobic intraocular lens following posttraumatic cataract surgery: A first-ever case report

A 19 year old male presented with complaints of diminution of vision in right eye. He had undergone cataract surgery in right eye elsewhere 6 years ago for firecracker injury. On examination, eccentric pupil is noticed with intraocular lens (IOL) opacity. on dilatation, rest of the intraocular lens is clear. As the rest of the IOL, which was protected by iris, was noted to be clear, the opacification at pupillary area suggests it to be secondary to air bubble contact .IOL exchange was done and explanted was tested and got confirmed as hydrophobic material. There are cases reports of IOL opacification post intra cameral air injection in hydrophilic lenses, to our knowledge this is the first case report of IOL opacification in hydrophobic lenses. with this case report we want to highlight the fact that one should be careful before intracameral air injection in eyes with both types of IOL.

Intraocular lens opacification after Descemet's stripping automated endothelial keratoplasty

Compared with conventional penetrating keratoplasty, Descemet's stripping automated endothelial keratoplasty (DSAEK) more effectively maintain global integrity and rapid vision rehabilitation with less ocular surface disorders in patients with endothelial dysfunction. Here, we report a case of a 76-year-old woman who experienced opacification of a hydrophilic intraocular lens (IOL) approximately 10 months after DSAEK. The patient with no history of systemic disease developed pseudophakic bullous keratopathy in the right eye 2 years after undergoing cataract surgery. The best-corrected visual acuity (BCVA) of the right eye was Snellen 0.01 when presented to our hospital. DSAEK was arranged and performed smoothly. However, the graft detached over the upper part of the cornea on postoperative day 1. Thus, rebubbling was performed immediately. After the procedure, the graft was well attached, and the cornea became clear gradually. The BCVA returned to Snellen 0.6. However, progressive opacification over the anterior surface of the IOL was observed 10 months postoperatively. Vision deteriorated to 0.5 with various refractive errors during 2-year follow-up. IOL exchange may be considered if the vision is getting worse. IOL opacification may result from a direct contact between the IOL surface and exogenous air, particularly in a hydrophilic IOL, and can be a rare but significant complication after DSAEK. Clinicians planning to perform DSAEK should consider the composition of the IOL, the amount of intracameral air, duration of air filling, and high intraocular pressure.

Management of Descemet’s Membrane Detachment by Intra Cameral Air Injection

Management of Descemet’s Membrane Detachment by Intra Cameral Air Injection

Management of acute corneal hydrops in keratoconus with pre‐Descemet's membrane sutures

PurposeTo report three cases of corneal hydrops in patients with keratoconus that were managed with pre‐descemet's membrane (DM) sutures associated with intracameral air injection assisted with the ZEISS RESCAN 700 surgical microscope under general anesthesia to shorten the period of corneal edema, to achieve corneal stability and to reduce the duration of the use of carbonic anhydrase inhibitor.MethodsThe first patient, a 27‐year‐old man affected by a Down's syndrome associated with a bilateral keratoconus presented with corneal hydrops in his right eye resulting from a central vertical tear in DM. Three horizontal pre‐DM sutures were performed. The second patient, a 26‐year‐old man affected by a Down's syndrome associated with a bilateral keratoconus presented with corneal hydrops in his left eye resulting from a central horizontal tear in DM. Five vertical pre‐DM sutures were achieved. The third patient, a 43‐year‐old woman with bilateral keratoconus presented with corneal hydrops in her left eye resulting from a central vertical tear in DM. Four horizontal pre‐DM sutures were achieved.ResultsOne month after the pre‐DM sutures, the edema resolved clinically and the pachymetry dramatically decreased on anterior segment OCT. The visual acuity of the Two first patients, while subjectively improved, were not measurable, the third patient visual acuity improved from counting fingers at 1 foot to 1,4logMAR at 20 foots from day one to month six.ConclusionsIntrastromal pre‐DM sutures and intracameral air injection could promptly restore imperviousness of posterior stroma. This technique seems to be a useful procedure to shorten acute corneal hydrops. This impressive clinical response to stromal sutures led us to hypothesize that the pathogenesis of corneal hydrops may correspond to an acute ‘fracture’ of the corneal stroma secondarily leading to DM tear.

Rebound tonometry over an air-filled anterior chamber in the supine child after intraocular surgery

Intracameral air is a critical component of multiple ophthalmic surgical procedures and is frequently used in pediatric intraocular surgery. Among other benefits, it helps to facilitate postoperative examination in uncooperative children by allowing quick confirmation of a formed anterior chamber. The purpose of this study was to evaluate the usefulness and accuracy of a position-independent rebound tonometer (Icare PRO) in measuring intraocular pressure (IOP) intraoperatively in pediatric eyes with intracameral air compared to a commonly used handheld applanation tonometer (Tono-Pen XL). In this prospective study of sequential children undergoing intraocular surgery, IOP was measured immediately following general anesthesia induction using both Icare PRO rebound tonometry and Tono-Pen XL tonometry, with instrument order randomized, in the supine child's eye(s). At completion of surgery after standard placement of intracameral air IOP was again measured using both instruments. A total of 42 eyes of 30 children were included. Surgeries included glaucoma (25), cataract-related (16), and both (1). Mean preoperative IOP by Tono-Pen XL was 23.52±9.76mm Hg; by Icare PRO, 20.94±10.01mm Hg (P=0.0012). Mean IOP over intracameral air at surgery conclusion by Tono-Pen XL (n=41) was 12.66±4.90; by Icare PRO (n=42), 12.96±5.10mm Hg (P=0.46). One eye had postoperative IOP unrecordable by Tono-Pen XL but 7.9mm Hg by Icare PRO. Bland-Altman analysis, which included only paired measurements, showed a preoperative mean difference in IOP (ΔIOPT-I) of 2.58mm Hg (95% CI, -6.86 to 12.02); postoperative mean ΔIOPT-I of -0.42mm Hg [95% CI, -7.57 to 6.73]. Position-independent rebound tonometry (Icare PRO) accurately measured IOP in supine children's eyes postoperatively in the presence of intracameral air.

Evaluation of Time to Donor Lenticule Apposition Using Intraoperative Optical Coherence Tomography in Descemet Stripping Automated Endothelial Keratoplasty.

To evaluate the time to donor lenticule apposition in cases of Descemet stripping automated endothelial keratoplasty (DSAEK) using microscope-integrated intraoperative optical coherence tomography (iOCT). Thirty eyes of 27 patients planned to undergo Descemet stripping automated endothelial keratoplasty were enrolled in this prospective study. In group I (n = 10), continuous intracameral positive pressure was maintained for 8 minutes. In group II (n = 10) and group III (n = 10), external corneal massage was initiated simultaneously with positive intracameral air pressure. The external corneal massage was continued till complete resolution of interface fluid; the positive intracameral pressure was maintained for 8 minutes in group II and for 5 minutes in group III. The host-donor relationship was continuously monitored with the iOCT. The main outcome measure was time to complete donor lenticule apposition. In group I, the interface fluid persisted after 8 minutes of positive intracameral pressure in all eyes (10/10); hence an external corneal massage was required to achieve optimal donor adherence. In groups II and III, all eyes (20/20) had complete resolution of the interface fluid at the end of 3 minutes. In 100% of the eyes (30/30), the grafts were attached after anterior chamber decompression as seen on the iOCT. In all cases, the donor lenticules were adhered in the postoperative period. iOCT helps in understanding that the donor lenticule is well apposed within 1 to 3 minutes with the technique of simultaneous positive intracameral pressure and external corneal massage. This knowledge minimizes the waiting time for graft apposition and prevents prolonged intraocular pressure elevation.

Morphometric changes of corneal endothelial cells following intracameral air for micro perforation of the Descemet Membrane during big-bubble deep anterior lamellar keratoplasty

AimThe aim of this study was to assess the effect of intracameral air on the endothelial cell morphometrics. Patients and methodsThis is a retrospective controlled interventional cohort study of 26 patients (18 males and 8 females) who underwent unilateral deep anterior lamellar keratoplasty (DALK) for moderate keratoconus. The DALK patients were divided into two groups: a treatment group (14), which had micro perforations of the Descemet Membrane (DM) intraoperatively and received intracameral air at the end of the surgery; and an independent control group (12), which had no micro perforation and thus no intracameral air was injected. Postoperative best corrected visual acuity (BCVA), sphere, cylinder, spherical equivalent (SEQ), central corneal thickness, and endothelial cell morphometric features consisted of the endothelial cell density (ECD), polymegathism, and pleomorphism were compared between treatment and control groups. ResultsThe mean BCVA was 0.36±0.36 logMAR in the treatment group and 0.17±0.11 logMAR in the control group (p=0.081), and the mean corneal thickness was 507.86±62.69μm in the treatment group and 525.67±37.54μm in the control group air (p=0.399). Furthermore, the mean sphere was −5.14±4.17D and −1.02±3.29D, the mean cylinder was −3.16±2.20D and −2.88±1.21D, and the mean SEQ was −6.72±4.66D and −2.46±3.14D and in the treatment and control groups respectively (p=0.011, 0.693, and 0.013). As to morphometric features, the mean ECD was 2176.76±549.18cell/mm2 and 2257.30±436.12cell/mm2 in the treatment and control groups respectively (p=0.686), and the mean pleomorphism 0.48±0.09 and 0.54±0.10 in the treatment and control groups respectively (p=0.139). In contrast, the mean polymegathism was 0.37±0.06 and 0.31±0.05 in the treatment and control groups respectively (p=0.009). ConclusionThe presence of air inside the anterior chamber for a short term may not cause further endothelial cell loss and can be safely performed to prevent postoperative Descemet Membrane detachment in case of micro perforations.

Immediate Postoperative Intraocular Pressure Changes After Anterior Chamber Air Fill in Descemet Membrane Endothelial Keratoplasty.

To monitor the intraocular pressure (IOP) changes immediately after anterior chamber air tamponade in Descemet membrane endothelial keratoplasty (DMEK). Twenty-four patients undergoing DMEK and 16 patients undergoing rebubbling after DMEK were enrolled (n = 40). All DMEK patients had inferior iridectomy and nearly full intracameral air tamponade with an aimed IOP of 25 mm Hg at the end of surgery. The IOP was measured at 1, 2, 3, 5, 12, 24 hours and 1 week postoperatively. After anterior chamber air fill in DMEK, the IOP increased from preoperative baseline, 12.1 ± 2.9 mm Hg, to 26.3 ± 4.7 mm Hg, P < 0.001. Mean IOP was significantly elevated in the first 2 hours, 19.4 ± 10.5 mm Hg and 17.0 ± 7.4 mm Hg, P = 0.007 and 0.006, respectively. Then, it lowered to the baseline level, 14.0 ± 4.7 mm Hg, P > 0.05, and remained stable during follow-ups. An asymptomatic IOP elevation above 30 mm Hg was detected in 3 patients (12.5%) within the first 2 hours. None had preexisting glaucoma. Most episodes could be controlled by antiglaucoma medications and upright positioning. The pattern of IOP changes after rebubbling was similar to that after DMEK but the IOP dropped sharply to the baseline level after 1 hour and had no incidence of IOP elevations beyond 30 mm Hg. Adequate inferior iridectomy greatly alleviates the risk and severity of acute IOP rises after nearly full anterior chamber air tamponade in DMEK. Standard IOP adjustment at the end of DMEK surgery with postoperative IOP monitoring especially in the first 2 postoperative hours is advisable when there is no postoperative default air release.

Anterior Segment Optical Coherence Tomography-Guided Management Algorithm for Descemet Membrane Detachment After Intraocular Surgery.

To evaluate the role of anterior segment optical coherence tomography (ASOCT) in the detection and management of Descemet membrane detachment (DMD) in cases of persistent corneal edema after intraocular surgery. An ASOCT-guided new algorithm for the management of such DMDs is described. Thirty-seven consecutive cases of persistent corneal edema of more than 2-week duration after intraocular surgery were included. All cases referred had no response to medical therapy. ASOCT was performed in all eyes. DMDs that were in the superior half of the cornea with a planar configuration alone were managed using intracameral air, and those with scrolled edges were managed using intracameral 14% perfluoropropane (C3F8). DMDs that were in the inferior half of the cornea with planar or scrolled edges were managed using intracameral C3F8 injection. The parameters evaluated were the type and morphology of DMD, resolution of DMD, and best-corrected visual acuity. Using ASOCT, DMD was found to be present in 25 eyes. All cases had planar edges, and 52% (13/25) cases had scrolled edges. In 48% (12/25) cases, DMD was peripheral. Descemetopexy with intracameral air or 14% C3F8 gas showed resolution in all cases with the mean time to resolution being 16.0 ± 7.1 days. ASOCT is a useful tool for timely diagnosis, characterization, and management of DMD in cases of nonresolving postoperative corneal edema. A new algorithm for intracameral injection of air or C3F8 in these cases helps to defer corneal transplantation.

Rebound tonometry over an air-filled anterior chamber in the supine child after intraocular surgery

To evaluate the usefulness/accuracy of a position-independent rebound tonometer (Icare Pro) to measure intraocular pressure (IOP) intraoperatively in pediatric eyes with intracameral air, by comparing with applanation tonometry (Tonopen XL) as gold standard.

Comparison of Sulfur Hexafluoride 20% versus Air Tamponade in Descemet Membrane Endothelial Keratoplasty

To compare clinical outcomes using 20% sulfur hexafluoride (SF6) versus 100% air as a tamponade for graft attachment in Descemet membrane endothelial keratoplasty (DMEK). Retrospective, comparative, interventional case series. Pseudophakic patients with Fuchs' endothelial dystrophy or pseudophakic bullous keratopathy that underwent DMEK using either 20% SF6 (group 1; 42 eyes) or 100% air (group 2; 39 eyes) tamponade between April 2010 and August 2011. A bimanual infusion technique was used to introduce and position the donor endothelium-Descemet membrane graft tissue. Outcome measures were analyzed at the following time points: before surgery, 3 and 6 months after surgery, and at yearly intervals up to at least 3 years. Corrected distance visual acuity (CDVA), manifest refraction, pachymetry, central endothelial cell count (cECC), complications, and rebubbling rates. Three years after surgery, mean CDVA improved from 0.48±0.45 logarithm of the minimum angle of resolution (logMAR) to 0.04±0.23 in group 1 (P < 0.001) and from 0.67±0.45 logMAR to 0.09±0.13 logMAR in group 2 (P < 0.001). The percentage of eyes with CDVA of 20/25 or more was 85.71% (36/42 eyes) in group 1 and 82.05% (32/39 eyes) in group 2 (P = 0.43). Mean preoperative cECCs and at last follow-up were: group 1, 2525±338 cells/mm(2) and 1758 ± 398 cells/mm(2) (mean cell loss, 30±11%; P = 0.008); and group 2, 2492±204 cells/mm(2) and 1678±373 cells/mm(2) (mean cell loss, 32±13%; P = 0.008). Endothelial cell loss was similar in both groups (P = 0.65). Intracameral air reinjection was needed in 1 patient in group 1 (2.38%) and in 5 patients in group 2 (12.8%). The rebubbling rate was significantly higher in group 2 (P = 0.004). No episodes of immunologic graft rejection were documented. Although clinical outcomes and corneal endothelial cell loss were similar in both groups, tamponade with 20% SF6 yielded a significantly lower incidence of graft detachments that may warrant its routine use in DMEK. Longer-term, randomized studies are needed to recommend this approach fully.

Management of corneal hydrops using air and micro-punctures

Case reportA 22-year-old woman with an acute hydrops and Descemet membrane detachment was managed by intracameral air injection combined with multiple corneal stromal venting incisions for the drainage of intrastromal fluid. No intraoperative complications were encountered, and the intrastromal fluid was resolved over 2 weeks. DiscussionAcute corneal hydrops is a significant complication of keratoconus. If not treated, resolution usually occurs over a period of 2–4 months. The persistent edema can cause complications, such as corneal neovascularisation, infection and corneal perforation.