Rupture Of Descemet's Membrane Research Articles

Blast injury: Impact to the cornea

Visual disorders are common even after mild traumatic brain injury (mTBI) or blast exposure. The cost of blast-induced vision loss in civilians, military personnel, and veterans is significant. The visual consequences of blasts associated with TBI are elusive. Active military personnel and veterans report various ocular pathologies including corneal disorders post-combat blasts. The wars and conflicts in Afghanistan, Iraq, Syria, and Ukraine have significantly increased the number of corneal and other ocular disorders among military personnel and veterans. Binocular vision, visual fields, and other visual functions could be impaired following blast-mediated TBI. Blast-associated injuries can cause visual disturbances, binocular system problems, and visual loss. About 25% of veterans exposed to blasts report corneal injury. Blast exposure induces corneal edema, corneal opacity, increased corneal thickness, damage of corneal epithelium, corneal abrasions, and stromal and endothelial abnormality including altered endothelial density, immune cell infiltration, corneal neovascularization, Descemet membrane rupture, and increased pain mediators in animal models and the blast-exposed military personnel including veterans. Immune response exacerbates blast-induced ocular injury. TBI is associated with dry eyes and pain in veterans. Subjects exposed to blasts that cause TBI should undergo immediate clinical visual and ocular examinations. Delayed visual care may lead to progressive vision loss, lengthening/impairing rehabilitation and ultimately may lead to permanent vision problems and blindness. Open-field blast exposure could induce corneal injuries and immune responses in the cornea. Further studies are warranted to understand corneal pathology after blast exposure. A review of current advancements in blast-induced corneal injury will help elucidate novel targets for potential therapeutic options. This review discusses the impact of blast exposure-associated corneal disorders.

Retrospective Analysis of a New Intrastromal Dissection Technique Using the Retinal Reflex for Deep Anterior Lamellar Keratoplasty.

The purpose of this study was to describe a new surgical technique for deep anterior lamellar keratoplasty. All pupils in the recipient eyes were dilated preoperatively. Vertical grooving was performed using a crescent blade with a width of 5 mm and a depth of one-third to half corneal thickness on the temporal side of the limbus. Stromal dissection was performed as close as possible to Descemet membrane by observing the gap between the gold line by retinal reflex and the front edge of the crescent blade. Lamellar dissection was performed along the lamellar plane using corneal dissectors. The ophthalmic viscoelastic device was injected into the intrastromal pocket to separate the anterior and posterior stroma and an anterior corneal lamella was excised. A donor cornea was sutured into the recipient bed. In 18 eyes, none of the patients had Descemet membrane rupture during surgery. The mean postoperative residual stromal thickness was 80 ± 31 μm. The mean central corneal thickness after surgery was 660 ± 69 μm. At the last follow-up, the cornea was cleared in all 18 eyes on slit-lamp examination. We estimated the residual stromal thickness based on the gap between the gold line by the retinal reflex and crescent blade, and intrastromal lamellar dissection was performed using a smooth corneal dissector. Consequently, the surface of stromal dissection was smooth, and the residual stromal thickness was even.

Deep Anterior Lamellar Keratoplasty-Treated Keratoconic Eyes With Descemet Membrane Rupture.

The aim of this study was to evaluate the outcomes of deep anterior lamellar keratoplasty (DALK) and compare it with penetrating keratoplasty (PKP) in keratoconic eyes with Descemet membrane (DM) rupture. In this comparative retrospective case series, 33 keratoconic eyes with a history of hydrops underwent DALK and 27 received PKP. Baseline and postoperative visual acuity, corneal astigmatism, mean keratometry, endothelial cell density, and complication rates were measured. The median follow-up of patients who underwent DALK was 45 months (range, 4-76 months) and that of patients who underwent PKP was 84 months (range, 4-136 months). Both procedures had comparable postoperative visual acuity, astigmatism, and mean keratometry. Significantly higher endothelial cell densities were observed in DALK than in PKP at 2, 3, and 5 years postsurgery (2043 ± 767 vs. 1165 ± 683 cell/mm2, P = 0.007, n = 12 in both groups at 2 years). Intra-DALK, 15 perforations occurred (44.12%) and 1 (2.94%) was converted to PKP. Graft rejection was diagnosed in 1 (3.03%) DALK procedure versus 8 (29.63%) PKP (P = 0.008), and other long-term complication rates were equivalent. Kaplan-Meier survival analysis also revealed a higher rejection-free survival rate for the DALK group (P = 0.012). Subgroup analysis within both groups based on the severity of preoperative DM rupture revealed no significant difference in any major 2-year outcomes. DALK showed similar beneficial visual outcome and safety but significantly better endothelial protection over PKP in eyes with keratoconus and previous hydrops. Therefore, DALK is recommended in posthydrops cases irrespective of the DM rupture severity.

Acute Corneal Hydrops in Keratoconus Coinciding With COVID-19 Infection.

To the Editor: Acute corneal hydrops (AH), characterized by corneal stromal edema after a Descemet membrane rupture that allows aqueous humor entry, is observed in cases of keratoconus. Patients typically present with rapidly deteriorating visual acuity, photophobia, and pain. A timely diagnosis and management are essential to ruling out other vision-threatening pathologies such as corneal edema, infectious keratitis, uveitis, Fuchs endothelial dystrophy, postoperative edema, and acute transplant rejection. Here we describe a case of AH in a patient with keratoconus coinciding with coronavirus disease 2019 (COVID-19) infection and emphasize the importance of patient education in the context-restricted face-to-face consultations. A 20-year-old healthy man was evaluated regularly every 3 months for keratoconus using visual acuity and refraction assessments and anterior segment optical coherence tomography imaging. He wore corneal rigid gas-permeable contact lenses in both eyes. He also had a mild ocular allergy but no atopy or habit of eye-rubbing. There was no family history of keratoconus. A year earlier, he had an episode of AH in his left eye. While his left eye stabilized after pressure patching, the keratoconus progressed in his right eye. Examination findings at his last visit before the COVID-19 diagnosis included: corrected distance visual acuity with a gas-permeable contact lens of 20/30 (right) and 20/16 (left), anterior keratometry of 66.4 D (right) and 43.5 D (left), the thinnest corneal thickness of 264 mm (right) and 468 mm (left), and posterior “best-fit sphere” 9-mm radius values of 4.88 (right) and 6.46 mm (left). Approximately 2 months after the last follow-up, he developed flu-like symptoms (sore throat and fever) and was diagnosed the next day with COVID-19 on polymerase chain reaction. Two days after symptom onset, he noticed sudden deterioration of vision in his right eye and called our hospital. The cornea specialist in the ophthalmology department made a tentative phone diagnosis of AH based on his ocular history and instructed him to apply a pressure patch with ophthalmic ointment. He was examined at our hospital after 10 days of quarantine. The corrected distance visual acuity of the right eye was 20/2000, while a slitlamp examination revealed corneal protrusion and marked corneal epithelial as well as stromal edema in the right eye. Fluorescein corneal observation showed no epithelial abnormality, and a definitive AH diagnosis was made. Optical coherence tomography imaging revealed a break in Descemet membrane with overlying corneal edema (Supplemental Digital Content Fig. 1, https://links.lww.com/APJO/A179). No abnormality was noted in the left eye. He had received the second COVID-19 vaccine dose 1 month before the viral infection and reported experiencing no vaccine-related complications. On examination a month later, the AH in the right eye had remarkably improved. Various ophthalmic management and care delivery experiences have been reported during the COVID-19 pandemic. Perspectives in corneal crosslinking were reported relating to keratoconus in particular.1,2 To the best of our knowledge, our case is the first of AH with concomitant keratoconus and COVID-19 infection, although it was not possible to demonstrate a clear association among them. A previous history of AH in either eye is a predisposing risk factor for AH.3 This case underscores the importance of informing patients of their disease status and the need to undergo regular examinations. However, patients with COVID-19 may not be able to receive a timely ophthalmic examination. This patient was distressed until the postquarantine ophthalmic examination was performed; however, his previous experience with AH including successful pressure patching was helpful for the clinician and patient, who was better able to understand the extent of his condition and follow the provided instructions. In the absence of a clinical history of keratoconus, effectively managing AH before a face-to-face examination could be performed would have been challenging. Here are summary points of consideration when educating a patient with an acute event during a pandemic setting: Recognize the patient’s distress due to being in isolation during the acute event. Provide clear information about the disease and instructions for its independent management during quarantine. Strict hand hygiene should be thoroughly practiced while applying the pressure patch and patients should keep unwashed hands away from their face at times. Remote management may require conservative management methods. This requires careful consideration, particularly in acute ophthalmic cases. Although keratoconus was previously considered a noninflammatory ectatic corneal disease, recent evidence shows a relationship between its pathogenesis and chronic inflammatory events.4,5 Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is known to cause a proinflammatory state.6 There are several reports of corneal graft rejection in patients infected with COVID-19.6–8 Large population-based case-control studies are needed to investigate the possible association between AH in keratoconus and the SARS-CoV-2 cytokine response. Shizuka Koh, MD, PhD*† Takeshi Soma, MD, PhD† Vishal Jhanji, MD‡ Kohji Nishida, MD, PhD†

Bilateral keratoconus hydrops in a patient with Down Syndrome: a case report

Background: Keratoconus has been reported in as many as 8% to 36% of people with Down syndrome. Corneal hydrops, a complication of advanced keratoconus, is characterized by the sudden onset of severe stromal and epithelial edema resulting from descemet membrane rupture. According to previous studies, acute corneal hydrops occurs in between 0.2% and 2.8% of keratoconus patients, while the incidence of corneal hydrops in Down syndrome patients with keratoconus is unclear. This study aims to evaluate the bilateral keratoconus hydrops in a patient with Down Syndrome. Case Presentation: We reported a case of bilateral corneal hydrops in a Down syndrome patient aged 28. Upon arrival, his bilateral visual acuity was fixed to follow the object. Slit-lamp examination revealed bilateral corneal edema and apical corneal scarring, and grade 4 plus keratoconus were seen on the Scheimpflug camera system. The patient receives medical treatment to lessen the patient's symptoms while they wait for a cornea donor to do a transplant. Conclusion: Patients with Down syndrome could experience bilateral corneal hydrops. Strong symptom communication, quick referral, and good cooperation during eye examinations are needed for early detection of this eye condition.

Deep Anterior Lamellar Keratoplasty: Can All Ruptures Be Fixed?

The aim of this study was to report our experience in managing different types of Descemet membrane (DM) ruptures during deep anterior lamellar keratoplasty (DALK). This study was a retrospective, consecutive, interventional case series of 1573 DALK procedures conducted on 1244 patients, performed between 2002 and 2017. Inclusion criteria consisted of a minimum of 24-month follow-up. DM rupture incidence, location, and surgical approach for repair were recorded. Postoperative measures were investigated only in eyes that experienced DM ruptures and included best spectacle-corrected visual acuity, endothelial cell loss, double anterior chamber, pupillary block, need for rebubbling, graft clarity, and rejection episodes. One thousand four hundred forty-three eyes met the inclusion criteria. DM ruptures occurred in 119 eyes (8.25%). Seventy-eight percent of DM ruptures were microruptures (≤2 mm), and they occurred more frequently during manual DALK cases. Macroruptures were less frequent (22%), and they occurred more frequently during subtotal and total anterior lamellar keratoplasty (STALK-TALK) cases. In general, DM ruptures mainly occurred in the peripheral cornea (95% of cases). One hundred (84%) of the 119 ruptures resolved by the first postoperative day. Nineteen cases (16%) developed double anterior chamber; all resolved by using different strategies. No intraoperative penetrating keratoplasty conversion was recorded. Pupillary block occurred in 7 cases (5.9%), but no Urrets-Zavalia syndrome was observed. The average postoperative endothelial cell loss was 410 ± 39 cells/mm 2 (19%) at 1-year follow-up, and there was no significant difference between cases requiring a rebubbling and cases that did not ( P = 0.896). All grafts but one were clear at the last follow-up. Graft failure from endothelial decompensation occurred in this lone case (0.8%). It is worth trying to repair all DM ruptures in DALK, and immediate penetrating keratoplasty conversion should be avoided. Understanding the physiomechanical mechanisms in DALK allows to correctly choose a proper rescue strategy to successfully repair DM ruptures.

Descemet stripping only and ripasudil for the treatment of traumatic Descemet's membrane ruptures.

Descemet´s membrane ruptures (with a discontinuation of Descemet´s membrane and double detached coiled edges) in the context of complicated anterior segment surgery have rarely been described and its management can be challenging. We report a modified Descemet stripping only (DSO) technique associated with ripasudil drops to treat these cases when other techniques fail. We describe two cases of large Descemet´s membrane detachments associated with Descemet´s ruptures after cataract surgery that did not respond to two SF6 intracameral injections. As the detached Descemet's membrane and coiled edges might have prevented endothelial cell migration, we decided to perform a modified DSO with post-operative ripasudil drops to promote corneal clearance. Both cases improved significantly in unaided and best corrected visual acuity (BCVA), corneal clearance and pachymetry, avoiding the need for an endothelial keratoplasty. Endothelial cells were observed on specular microscopy within the area of the descemetorhexis. DSO with ripasudil drops might be a valuable tool to recover corneal clearance and avoid endothelial keratoplasty in complex Descemet´s membrane detachments with ruptures that do not respond to other treatments.

Descemet’s membrane rupture due to forceps injury: macroscopic aspect by anterior segment optical coherence tomography

AbstractPurposeTo describe corneal changes after birth trauma from forceps delivery, using anterior segment optical coherence tomography (AS‐OCT), in order to reduce the risk of potential anisometropic amblyopia.MethodsA 73‐year‐old female patient came to the ocular surface section consulting for dry eye disease symptoms. At the slit lamp examination, a vertical endothelial stria was observed in the right eye. After an exhaustive anamnesis, the patient referred having a traumatic birth in which forceps had been used.ResultsAn AS‐OCT was performed, showing a vertical rupture in the Descemet membrane secondary to traumatic birth with forceps.ConclusionsDescemet’s membrane rupture can cause corneal oedema which usually clears over time, but those ruptures often persist. The residual corneal changes can result in anisometropia and the main cause of vision loss after such injury is anisometropic amblyopia. The AS‐OCT is a useful diagnostic tool to detect these alterations at early stages.BibliographySarma P, Borgohain M, Tayab S, Sangma CA. Descemet's membrane rupture secondary to forceps‐induced birth injury. Indian J Ophthalmol. 2020;68(10):2253. https://doi.org/10.4103/ijo.IJO_149_20Alobaidy R, Srinivasan S. Forceps‐induced birth injury to the cornea. BMJ Case Rep. 2014;2014:bcr2013201786. Published 2014 Apr 9. https://doi.org/10.1136/bcr‐2013‐201786

Acute Hydrops After Bowman Layer Transplantation for Keratoconus May Indicate that Descemet Membrane Rupture Is Secondary to Hydrops.

The aim of this study was to review the postoperative course and imaging features of 7 eyes that presented with corneal hydrops after Bowman layer (BL) transplantation was performed for advanced keratoconus to determine the potential mechanisms of hydrops formation. A retrospective analysis was performed of 7 eyes of 5 patients with advanced keratoconus that underwent midstromal BL transplantation at 2 tertiary referral centers and developed acute corneal hydrops on average 64 (±30) months (range 14-104 months) postoperatively. Corneal tomography and anterior segment optical coherence tomography (AS-OCT) images were reviewed to document the postoperative and posthydrops course. For all eyes, the post-BL transplantation course was uneventful until hydrops development. Despite stable postoperative topographies in 5 of 7 eyes, eyes developed hydrops with typical hypodense areas on AS-OCT that were limited to the stromal layers posterior to the BL graft. With AS-OCT (6/7 eyes), 2 eyes showed a break in Descemet membrane, whereas Descemet membrane was intact across the cornea in 2 eyes; in 2 eyes, the images were inconclusive. All patients admitted to continued eye rubbing, and all but 1 had a clinically significant allergy and/or atopic constitution. Most eyes (5/7) showed a relatively quick (visual) recovery within 1 to 4 months after hydrops. Hydrops formation in keratoconic corneas after midstromal BL transplantation may indicate that a break in Descemet membrane is secondary to hydrops development (and not vice versa). With a midstromal BL graft in situ limiting hydrops dimensions, resolution of the hydrops seemed relatively quick with recovery to prehydrops visual acuity in most eyes.

Descemet's membrane rupture secondary to forceps-induced birth injury.

Descemet's membrane rupture secondary to forceps-induced birth injury.

Femtosecond laser-assisted deep anterior lamellar keratoplasty.

A survey of the recent literature of deep anterior lamellar keratoplasty using femtosecond laser technology. There are several recent reports in the literature assessing technique and outcomes of deep anterior lamellar keratoplasty done with a femtosecond laser trephination. Most of these reports are laboratory studies and small case series with short-term outcomes. The laser technology is expensive and may not produce better results than conventional manual techniques. However, there are several theoretical advantages to femtosecond laser incisions in deep anterior lamellar keratoplasty that should be explored, including possible increased success of Descemet's membrane separation from stroma during surgery as well as postsurgical astigmatism benefits, earlier suture removal, and increased wound strength and healing. Femtosecond laser trephination in the setting of DALK may improve the technique by decreasing the number of descemet's membrane ruptures and improving short-term and long-term outcomes as compared with manual techniques. However, there is no consensus on a standardized approach for wound design or postoperative management. The literature would benefit from a prospective randomized controlled trial.

Phacoemulsification with big-bubble deep anterior lamellar keratoplasty: Variant of the triple procedure

The surgical treatment of patients with combined advanced ectasia and cataract present is challenging. The most common approach is a corneal graft followed by cataract surgery at a later date. A second option is simultaneous corneal grafts with cataract extraction and intraocular lens implantation. This triple procedure has several benefits, which include a shorter period of visual disability and lesscost to the patient than the 2-stage technique. There have been attempts to combine phacoemulsification and deep anterior lamellar keratoplasty (DALK) to maximize the advantages of both procedures in a single sitting. Some authors suggest a triple procedure in which the big-bubble DALK technique is performed before phacoemulsification; however, they recommend that phacoemulsification be performed with extreme caution to prevent Descemet membrane rupture. We describe a variant of the triple procedure in which phacoemulsification is followed by a corneal graft using the big-bubble DALK technique.

ACUTE CORNEAL HYDROPS IN KERATOCONUS – A CASE REPORT

Keratoconus is observed in cases of impaired corneal biochemical activity, leading to secondary thinning and ectasia. Usually the onset is in the second – third decade of life. The acute corneal hydrops occurs when intraocular aqueous passes through a rupture of Descemet membrane (DM) and is characterized with stromal edema. Estimated frequency is 2.5 – 3.0% among the keratoconus patient. Eye rubbing is the major risk factor. In most cases the hydrops persists for 2 -4 months. The resolution is cicatrix/scar formation, but there is a risk for complications such as vascularization, infection and corneal perforation. We present a case of a 23 year old male patient, presenting with complains of reduced and blurry vision in the right eye and photophobia. Visual acuity and full ophthalmological examination was done. UBM was performed of the right eye. The patient received conservative therapy. The acute corneal hydrops occurs when intraocular aqueous passes through a rupture of Descemet membrane (DM) and is characterized with stromal edema. The treatment could be conservative or surgical. The conservative therapy includes topical lubricants, antibiotics, cycloplegics, hyperosmotic solutions, antiglaucoma drugs, topical corticosteroids and non-steroid anti-inflammatory drugs. Surgical treatment includes intracameral injection of air or gas, but the definitive treatment is penetrating keratoplasty. We describe a newly diagnosed patient with keratoconus, who presents with rare complication - acute corneal hydrops. Differential diagnosis in cases of young patients with acute onset of keratitis, especially young males, should be made with acute corneal hydrops.

Frequency of Complications During Preparation of Corneal Lamellae Used in Posterior Lamellar Keratoplasty Using the Pneumodissection Technique (Big Bubble).

To determine the frequency of formation of various types of bubbles and the potential impact of donor and lamella parameters on this frequency, and to identify possible risk factors of unsuccessful "big-bubble" creation in preparation of pre-Descemet endothelial keratoplasty and Descemet membrane endothelial keratoplasty with peripheral stromal support. Donor age and sex, death to preservation time (DPT), storage time, presence of corneal scars (mainly a condition after cataract surgery), and endothelial cell density of 256 donor corneas were assessed before Descemet membrane endothelial keratoplasty with peripheral stromal support or pre-Descemet endothelial keratoplasty lamella preparation using the big-bubble technique. Mean donor age was 62.3 ± 8.5 years (28.3% women and 71.7% men). Mean endothelial cell density of the donor graft was 2866 ± 255 cells/mm. Mean DPT was 10.12 ± 4.88 hours, and mean storage time of the transplant before surgery was 6.5 ± 4.8 days. Corneal scars were present in 17 donor grafts (6.6%) after cataract surgery. Eleven corneas were devalued because of Descemet membrane rupture during preparation (4.3%). In 182 corneas, standard bubble type I was created (71.7%); in 27 corneas, bubble type II was created; eventually, both types of bubbles formed simultaneously (10.5%); in 47 corneas, no bubble was created (18.4%). We identified higher endothelial cell density, shorter DPT, and the presence of corneal scars after cataract surgery as risk factors threatening successful bubble formation. The only risk factor for creating type II bubbles was higher donor age in our study.

Acute hydrops with a 180-degree massive edematous cavern demonstrated by three dimensional view of anterior segment optical coherence tomography in a patient with pellucid marginal corneal degeneration, a case report

BackgroundPellucid marginal corneal degeneration is a non-inflammatory disorder complicated by severe inferior corneal thinning. The central portion of the cornea, consequently, appears to protrude outwards, decreasing vision by means of an irregular stigmatism. Additionally, acute hydrops can occur in case of Descemet’s membrane rupture.Case presentationA 41-year-old Japanese woman presenting with severe visual loss in the left eye was examined and observed to have had full thickness corneal perforation as well as a Descemet membrane rupture with massive edema in the corneal stroma. Anterior segment optical coherence tomography-based corneal topography revealed a distorted crab claw sign indicating pellucid marginal corneal degeneration. The Descemet membrane rupture allowed acute hydrops to occur which was especially noteworthy given the scale of edema present within the stroma, rotating 180 degrees along the limbus, causing a smiley-face like lesion. We visualized it via a gonioscopic three-dimensional optical coherence tomography to build a three-dimensional video. Patient history revealed a previous acute hydrops in the right eye as well, which was ultimately treated with anterior lamellar keratoplasty, suggesting the pellucid marginal corneal degeneration had a classic bilateral involvement, which was also characterized with bilateral acute hydrops.ConclusionThis appears to be a very rare and interesting presentation of bilateral pellucid marginal degeneration, wherein not only acute hydrops formed bilaterally, but the cavity within the cornea stroma was exceptionally large with an unusual shape. Using the gonioscopic three-dimensional optical coherence tomography imaging, we were able to easily visualize the massive intrastromal cavern, and appropriately planned the crescent-shaped anterior lamellar keratoplasty. The 3d video constructed using this data is particularly elucidative compared to 2d images. As such, we recommend utilizing 3d imaging in cases where more conventional topography is not as explanatory with respect to precise nature of deformation.

Forceps trauma in a newborn presenting as iris heterochromia

Birth-associated ocular trauma is common and often minor, including subconjunctival and retinal haemorrhage and eyelid edema. Significant ocular trauma during birth, usually associated with forceps-assisted delivery, is rarer and can include Descemet's membrane rupture, lid lacerations, hyphema, Purtcher retinopathy, facial nerve palsy, corneal edema, and corneal laceration. We report the first case of ocular birth trauma from forceps presenting as isolated iris heterochromia and a pseudo rubeosis iridis, which completely resolved by 1month of age with no known adverse ocular sequelae.

Late spontaneous resolution of a double anterior chamber post deep anterior lamellar keratoplasty

A 31-year-old healthy male underwent deep anterior lamellar keratoplasty with big-bubble technique for treatment of keratoconus in his right eye. One week after surgery, he presented with detachment of the endothelium-Descemet complex with formation of a double anterior chamber, despite the apparent absence of an intraoperative Descemet membrane rupture. A subsequent intervention with the intent to relocate the corneal graft button was not effective, because the detachment appeared again one day later. The authors hypothesized that, at the time of the stromal dissection with big bubble technique, a small amount of air penetrated into the anterior chamber, creating a false pathway through the trabecular meshwork. The aqueous humor then penetrated the graft flowing through the false pathway, causing the endothelium-Descemet detachment. The persistence of that pathway, even after the intervention of graft repositioning, caused the failure of the latter procedure and persistence of the double chamber. We decided to wait and observe. The double anterior chamber spontaneously resolved in approximately three months.

Early Deep Anterior Lamellar Keratoplasty (DALK) for Acanthamoeba Keratitis Poorly Responsive to Medical Treatment.

To evaluate the success (eradication of infection) or failure (recurrence of infection in the cornea or sclera, or endophthalmitis) of early therapeutic deep anterior lamellar keratoplasty (DALK) for active Acanthamoeba keratitis (AK) poorly responsive to medical treatment. Retrospective, noncomparative case series of 11 patients (11 eyes) affected by active AK poorly responsive to medical treatment who underwent early therapeutic DALK. Surgery was performed in all cases within 30 to 60 days from the onset of symptoms. Corneal ulcer depth was less than 300 μm in all cases. A 3-drug combination (chlorhexidine gluconate, propamidine isethionate, and neomycin sulfate) was the antiamoebic protocol used preoperatively and postoperatively. Cannula big bubble and "layer-by-layer" manual dissection techniques were performed. Eradication of infection, episodes of rejection, postoperative endothelial cell density, and the best spectacle-corrected visual acuity were evaluated. Histologic examination of surgical margins was performed, and margin clearance was assessed. Mean follow-up was approximately 2 years. Four descemetic DALK and 7 predescemetic DALK were performed. One small Descemet membrane rupture occurred. Peripheral surgical margins were free of infection in all cases. Deep surgical margins not free from infection were found in 2 cases. However, no episode of infection recurrence was observed. The postoperative average best spectacle-corrected visual acuity was 0.8 (range, 0.6-1.0). No case of rejection was recorded. Early therapeutic DALK could be considered a new approach to eradicate active infection in AK cases poorly responsive to medical treatment, with significant ulcer in the optical zone. Further studies are needed to validate this new indication for DALK.

Closed-Globe Injuries of the Ocular Surface Associated with Combat Blast Exposure

To describe closed-globe conjunctival and corneal injuries and endothelial cell abnormalities associated with blast exposure and their relationships to other closed-globe injuries and blast-event characteristics. Observational cross-sectional study. Veterans with a history of blast-related traumatic brain injury (TBI). History and ocular examination, including slit-lamp biomicroscopy, gonioscopy, specular microscopy. Type and location of blast injuries to the conjunctiva and cornea. Ocular surface injuries were present in 25% (16 of 65) of blast-exposed veterans with TBI. Injuries included partial-thickness anterior stromal corneal scars (15 eyes), Descemet membrane ruptures (6 eyes), and conjunctival or corneal foreign bodies (7 eyes). Based on normative information from an age-matched comparison group, endothelial cell abnormalities were identified in 37% of participants. Eyes with ocular surface injury were more likely to have lower endothelial cell density, higher coefficient of variation of cell area, and lower percentage of hexagonal cells compared with eyes without injury. Presence of ocular surface injury or endothelial cell abnormalities was associated with elevated rates of other anterior and posterior segment injuries, as well as impairment of visual acuity. We found no relationship between ballistic eyewear use or severity level of TBI and presence of ocular surface injuries from blast. Independent of TBI severity or use of protective eyewear, ocular surface injuries and endothelial cell abnormalities were found in significant numbers of veterans with blast-related brain injury. Descemet membrane ruptures from blast exposure were described. Ocular surface trauma was associated with other ocular injuries throughout the globe. Potential mechanisms for the types and locations of ocular injuries seen were discussed. Any corneal or conjunctival injury in a blast survivor should prompt a thorough ocular trauma examination, including gonioscopy and specular microscopy, with appropriate follow-up for associated injuries. Longitudinal studies are required to determine long-term visual outcomes after blast exposure.

Lamellar Keratoplasty Following Thermokeratoplasty in the Treatment of Acute Corneal Hydrops

To observe the efficacy of deep anterior lamellar keratoplasty (DALK) for treatment of acute hydrops in keratoconus after anterior chamber paracentesis combined with thermokeratoplasty. Retrospective, noncomparative clinical case series. Twenty-one patients (21 eyes) suffering acute hydrops associated with keratoconus were treated first by anterior chamber paracentesis combined with thermokeratoplasty. At 1 week after the edema was absorbed, and Descemet membrane ruptures and stromal clefts were cured, all patients received modified DALK. Descemet membrane re-ruptures during surgery were recorded, if any. Graft transparency, visual acuity, recipient folds or opacity, and immune rejection were monitored for 6 months to 1 year. All the corneal edema alleviated rapidly, and the intrastromal clefts narrowed within 1 week after combined anterior chamber paracentesis and thermokeratoplasty. DALK was performed successfully in all patients within 2 weeks after the first surgical procedure, with no Descemet membrane rebreaking or corneal perforation. The recipients were completely clear in 7 eyes, and mild fusiform scars appeared at the central recipient in 14 eyes. All the opacity of Descemet membrane ruptures became slight or even disappeared after 6 months. The mean best-corrected visual acuity was improved to 20/30 at 1 year after DALK. No immune rejection occurred. Anterior chamber paracentesis combined with thermokeratoplasty can accelerate the absorption of corneal edema in patients with acute corneal hydrops (within 1 week) and Descemet membrane rupture healing without obvious opacity (within 2 weeks). During this window phase, DALK could be performed safely, and good visual acuity may be obtained.