Nonhealing Corneal Ulcers Research Articles

Clinical Efficacy of Fresh Amniotic Membrane Transplantation in Non- Healing Corneal Ulcer


 
 
 Objective: Severe corneal ulcer requires immediate intensive topical antibiotics, although potentially toxic to corneal epithelium and may contribute for prolonged corneal epithelial defect. Fresh-amniotic membrane transplantation (F-AMT) could act as an adjuvant therapy that counterbalances the epithelial toxicity effect and exerting antimicrobial actions. This study evaluates the clinical improvement and factors associated with the success rate of F-AMT using suturing technique. 
 Methods: This was a retrospective cohort study of 28 patients (28 eyes) conducted at Dr Sardjito General Hospital, Yogyakarta. Inclusion criteria were patients with severe corneal ulcer unresponsive to conventional medical treatment who underwent multilayer F-AMT using suturing technique. Clinical improvement such as hypopyon, size of the corneal defect, and antibiotic medication were evaluated. Results: Corneal epithelial healing was effectively restored at 25 days post F-AMT. There were statistically significant difference in patient’s blepharospasm (p= 0,00) and pain scale postoperative (p=0,00). There was no significant difference in patients visual acuity postoperative. Factors such as the size of the corneal defect, hypopyon, leucocyte count and neutrophil count were not correlated to epithelial healing. Failure was noted in 7 patients (25%) because of a persistent corneal defect. No patient developed major immediate postoperative complications. 
 Conclusion: F-AMT could be an optional adjuvant therapy with excellent results to treat non-healing severe corneal ulcer unresponsive to medical treatment by promoting epithelial healing. 
 
 

"Therapeutic Penetrating Keratoplasty: A Retrospective Review".

To report the indications, outcomes, and complications of therapeutic penetrating keratoplasty (Th PK) in patients with corneal perforation and/or nonhealing corneal ulceration. A retrospective review was conducted of 51 eyes of 51 patients undergoing Th PK between January 1, 2006 and April 15, 2016. Data collected included patient demographics, visual acuity (VA), size of the corneal infiltrate and epithelial defect, degree of corneal thinning/perforation, microbiological results, surgical details, and postoperative complications. The average age at presentation was 56.0 years (range 6-92 years), and most of the patients were females (n=31, 60.8%). Th PK was performed for corneal perforation in 28 eyes (54.9% of cases), nonhealing corneal ulcer in 16 eyes (31.4% of cases), and imminent risk of corneal perforation in 7 eyes (13.7% of cases). Infection was the most common reason for performing a Th PK and was present in 92.3% (47/51) of all cases. Of the infectious cases, the most common etiologies were bacterial (44.7%, 21/47) and fungal (31.9%, 15/47). The most common identifiable risk factor for undergoing a Th PK was a history of contact lens wear, which was seen in 32.7% of patients. Initial anatomic success was achieved in all patients after performing Th PK. Most patients (33/51; 64.7%) had clear grafts at their last follow-up examination. There was an improvement in VA in 70.2% (33/47, where data were available) of the patients at the final postoperative visit compared with the preoperative visit. Average best postoperative VA (1.14±0.88 logarithm of the minimum angle of resolution [LogMAR]; 20/276) was significantly better than the presenting (1.98±0.68 LogMAR; 20/1910) and preoperative (2.18±0.55 LogMAR; 20/3,027) visual acuities (P<0.0001). The most common complication after Th PK was cataract, which was present in 81.8% (27/33) of phakic eyes in which lens status could be assessed, followed by graft failure (47.1%; 24/51), and secondary glaucoma (45.1%; 23/51). Five eyes developed infection in the therapeutic graft, four eyes had persistent corneal epithelial defect at their last follow-up visit, and two eyes underwent evisceration. Therapeutic penetrating keratoplasty achieves anatomic success and it is a useful procedure for restoring a stable cornea in cases in which infection fails to heal or when the cornea perforates. Furthermore, Th PK achieves corneal clarity and improves vision in most patients.

Clinical Efficacy of Platelet-Rich Plasma in the Treatment of Neurotrophic Corneal Ulcer

Purpose Platelet-rich plasma (PRP) is an autologous blood product without preservatives and rich in proteins and growth factors which make it possible for cells to differentiate, proliferate, and migrate, thus stimulating healing and regeneration of tissues. The aim of this study was to evaluate the efficiency of autologous platelet-rich plasma in the treatment of neurotrophic keratopathy. Methods The study group consists of 25 patients with nonhealing corneal ulcers due to herpes simplex or herpes zoster infection and facial nerve or trigeminal nerve paralysis as a result of a neurosurgical operation caused by a tumour or stroke. The patients were given autologous platelet-rich plasma drops five times a day and additionally preservative-free artificial tears and a vitamin A ointment at night for maximum 3 months. The following were evaluated: best corrected visual acuity (BCVA), healing of corneal surface, subjective symptoms, and changes in corneal thickness with the use of anterior segment optical coherent tomography (AS-OCT). Results BCVA before the treatment was 0.10 ± 0.14, and after the treatment it was –0.3 ± 0.27 (p=0.001). Improved visual acuity and less subjective symptoms were observed in all patients. Complete healing of the ulceration was observed in 20 patients (80%). Four patients (16%) experienced considerable improvement of their clinical condition (reduced size and depth of the ulceration and inflammatory state: smaller conjunctival injection and swelling, improved visual acuity, and less subjective symptoms). In one of the patients, an amniotic membrane was transplanted due to the lack of improvement of his local condition. In all patients, the progression of corneal thinning was stopped. An average corneal thickness in its thinnest point was 322.3 ± 125.8 µm before the treatment, and 404.5 ± 118.7 µm (p < 0.05) after the treatment. None of the patients reported general or local side effects of the treatment. Conclusions Autologous platelet-rich plasma is a blood-based product which seems efficient in the treatment of neurotrophic keratopathy.

Лечение длительно незаживающей герпесвирусной язвы роговицы методом бесконтактной коагуляции (клинический случай)

Лечение длительно незаживающей герпесвирусной язвы роговицы методом бесконтактной коагуляции (клинический случай)

Topical Cross-Linked HA-Based Hydrogel Accelerates Closure of Corneal Epithelial Defects and Repair of Stromal Ulceration in Companion Animals.

The purpose of this study was to determine the safety of topical ocular administration of a cross-linked, modified hyaluronic acid (xCMHA-S) hydrogel, and its effectiveness in accelerating repair and closure of acute and nonhealing corneal ulcers in companion animals as a veterinary treatment and its utility as a model for therapy in human corneal ulceration. Two concentrations of xCMHA-S (0.33% and 0.75%) were topically administered to the eyes of rabbits six times daily for 28 days to assess safety. Then, 30 dogs and 30 cats with spontaneous acute corneal ulcers were treated with either xCMHA-S (0.75%) or a non-cross-linked hyaluronic acid (HA) solution (n = 15 per group for each species), three times daily until the ulcer had healed. Finally, 25 dogs with persistent nonhealing corneal ulcers were treated with xCMHA-S (0.75%) twice daily until the ulcer had healed. Both concentrations of the xCMHA-S hydrogel were well tolerated, safe, and nontoxic in the 28-day exaggerated dosing study in healthy rabbits. Topically applied xCMHA-S significantly accelerated closure of acute corneal stromal ulcers in dogs and cats compared with a non-cross-linked HA solution. Further, topical administration of the xCMHA-S aided in closure of nonhealing corneal stromal ulcers in dogs. Hyaluronic acid has previously been shown to aid in corneal wound repair. This study demonstrates that a cross-linked, modified HA hydrogel provides further benefit by accelerating time to corneal wound closure compared to a non-cross-linked HA solution in companion animals, and therefore may be beneficial in fulfilling an unmet need in humans.

Amniotic membrane in ophthalmology: properties, preparation, storage and indications for grafting-a review.

The use of amniotic membrane in ophthalmic surgery and other surgical procedures in the fields of dermatology, plastic surgery, genitourinary medicine and otolaryngology is on the increase. Furthermore, amniotic membrane and its epithelial and mesenchymal cells have broad use in regenerative medicine and hold great promise in anticancer treatment. Amniotic membrane is a rich source of biologically active factors and as such, promotes healing and acts as an effective material for wound dressing. Amniotic membrane supports epithelialization and exhibits anti-fibrotic, anti-inflammatory, anti-angiogenic and anti-microbial features. Placentas utilised in the preparation of amniotic membrane are retrieved from donors undergoing elective caesarean section. Maternal blood must undergo serological screening at the time of donation and, in the absence of advanced diagnostic testing techniques, 6months postpartum in order to cover the time window for the potential transmission of communicable diseases. Amniotic membrane is prepared by blunt dissection under strict aseptic conditions, then is typically transferred onto a nitrocellulose paper carrier, usually with the epithelial side up, and cut into multiple pieces of different dimensions. Amniotic membrane can be stored under various conditions, most often cryopreserved in glycerol or dimethyl sulfoxide or their mixture with culture medium or buffers. Other preservation methods include lyophilisation and air-drying. In ophthalmology, amniotic membrane is increasingly used for ocular surface reconstruction, including the treatment of persistent epithelial defects and non-healing corneal ulcers, corneal perforations and descemetoceles, bullous keratopathy, as well as corneal disorders with associated limbal stem cell deficiency, pterygium, conjunctival reconstruction, corneoscleral melts and perforations, and glaucoma surgeries.

Topical Coenzyme Q10 Eye Drops as an Adjuvant Treatment in Challenging Refractory Corneal Ulcers: A Case Series and Literature Review

The management of nonhealing corneal ulcers, particularly in patients with neurotrophic corneas, remains a challenging problem today. Some patients may fail to respond to conventional therapy, making new alternative agents necessary to treat these resistant cases. In this article, we aim to present six challenging cases of refractory corneal ulcers that revealed healing response to the adjuvant treatment with coenzyme Q10 (CoQ10) eye drops and to review the literature examining of new therapeutic agents. Our study was designed as a descriptive case series demonstrating the use of novel coenzyme Q10 eye drops in refractory corneal ulcers. In our case series, CoQ10 eye drops were added to the existing therapies as an adjuvant agent in six cases: three cases with neurotrophic corneal ulcers, two cases with postinfectious corneal ulcers (one unknown etiology+one Acanthamoeba keratitis), and 1 case with Stevens-Johnson syndrome. All cases were monitored regularly and corneal images were taken at all visits. All nonhealing corneas with conventional therapy revealed recovery after the addition of CoQ10 eye drops. Except for two cases that responded to the CoQ10 eye drops more rapidly (within 1 to 2 weeks), complete corneal healing was observed in four cases between weeks 4 and 8. No adverse events were reported in these cases throughout the follow-up period. Coenzyme Q10 eye drops can be considered as an important adjuvant therapeutic agent promoting corneal epithelial wound healing in challenging cases.

Cenegermin for the treatment of neurotrophic keratitis.

The trigeminal nerve provides corneal sensitivity and trophic supply to corneal tissues. The impairment of corneal innervation leads to development of neurotrophic keratitis (NK). NK is a rare, degenerative corneal disease characterized by corneal hypo/anesthesia and development of nonhealing corneal epithelial defects and ulcers. NK is a challenging condition with high medical need due to the lack of approved treatments that can restore corneal integrity. Current treatment of NK aims at stimulating corneal healing and preventing disease progression. Cenegermin is a recombinant human nerve growth factor that was safe and well tolerated in preclinical and clinical studies. Cenegermin eye drops were safe and effective in restoring corneal integrity in two phase II clinical trials in patients with NK. The European Commission granted a full marketing authorization to cenegermin eye drops for the treatment of moderate to severe NK in July 2017.

Active Pedicle Epithelial Flap Transposition Combined with Amniotic Membrane Transplantation for Treatment of Nonhealing Corneal Ulcers.

Introduction. The objective was to evaluate the efficacy of active pedicle epithelial flap transposition combined with amniotic membrane transplantation (AMT) in treating nonhealing corneal ulcers. Material and Methods. Eleven patients (11 eyes) with nonhealing corneal ulcer who underwent the combined surgery were included. Postoperatively, ulcer healing time was detected by corneal fluorescein staining. Visual acuity, intraocular pressure, surgical complications, and recurrence were recorded. Corneal status was inspected by the laser scanning confocal microscopy and anterior segment optical coherence tomography (AS-OCT). Results. The primary diseases were herpes simplex keratitis (8 eyes), corneal graft ulcer (2 eyes), and Stevens-Johnson syndrome (1 eye). All epithelial flaps were intact following surgery, without shedding or displacement. Mean ulcer healing time was 10.8 ± 3.1 days, with a healing rate of 91%. Vision significantly improved from 1.70 to 0.82 log MAR (P = 0.001). A significant decrease in inflammatory cell infiltration and corneal stromal edema was revealed 2 months postoperatively by confocal microscopy and AS-OCT. Corneal ulcer recurred in 1 eye. None of the patients developed major complications. Conclusion. Active pedicle epithelial flap transposition combined with AMT is a simple and effective treatment for nonhealing corneal ulcers.

A rare case of fungal keratitis: diagnosis and management

Introduction: We report a case of keratitis caused by a member of the Phoma species of fungi. Case presentation: A 59-year-old contact lens wearer developed a non-healing corneal ulcer. Microbiological culture and subsequent PCR analysis were performed using samples obtained from corneal scraping. A fungus, phenotypically identified as a member of the Phoma species of fungi, was cultured. PCR from infected tissue confirmed the diagnosis. Conclusion: Although rarely pathogenic to humans, members of the ubiquitous Phoma species of fungi can occasionally cause keratitis. Corneal microtrauma associated with contact lens wear is probably important in precipitating such infections.

Corneal Collagen Cross-linking for Treatment of Non-healing Corneal Ulcers.

Purpose:To evaluate the efficacy of corneal collagen cross-linking (CXL) for treatment of corneal ulcers not responding to antimicrobial therapy.Methods:Eight patients with corneal ulcers associated with corneal melting, not responding to conventional antibiotic therapy, were treated with CXL. The procedure was performed according to the standardized protocol for keratoconus. Preoperative medications were continued after CXL in all cases. Microbiological exams revealed Pseudomonas aeruginosa in 3 cases. Follow up continued from 1 to 10 months.Results:In 6 of 8 eyes, progression of corneal melting was halted and complete epithelialization occurred. In one eye emergency keratoplasty was needed due to corneal perforation. A conjunctival flap was performed to treat severe localized corneal thinning in one of the patients a few days after CXL. Significant clinical improvement occurred in all cases of Pseudomonas aeruginosa keratitis.Conclusion:CXL can be considered as a promising new treatment in the management of refractory non-healing corneal ulcers, including Pseudomonas aeruginosa keratitis.

An Unusual Case of Nonhealing Granulomatous Keratitis Caused by Mycobacterium chelonae in a Healthy Middle Aged Adult.

Purpose. To report a rare presentation of culture positive Mycobacterium chelonae (M. chelonae) corneal ulcer and its management. Case Report. We report a rare case with history of chronic pain and blurriness of vision. Examination revealed chronic nonhealing paracentral corneal ulcer inferiorly at 5 to 7 o'clock meridian with anterior chamber cells 1+ unresponsive to routine antibiotic and antifungal medications with Mantoux test (MT) positivity in a middle aged nondiabetic patient with no prior obvious history of trauma, ocular surgery, and contact lens usage. Discussion. Ziehl Neelsen (ZN) staining in nonhealing ulcer revealed acid fast bacilli typical of M. chelonae with subsequent culture positivity in Lowenstein Jensen (LJ) medium. Subsequent treatment with topical fortified amikacin and tobramycin resulted in rapid healing of corneal ulcer. Conclusion. M. chelonae presenting as a chronic nonhealing corneal ulcer spontaneously occurring in a healthy young adult with no predisposing factor draws the need to have a good index of suspicion by performing ZN stain and culture and its subsequent successful management with topical fortified amikacin and tobramycin.

Management of a unilateral non-healing corneal ulcer and uveitis in a laughing kookaburra (Dacelo novaeguineae)

A six-year-old male laughing kookaburra (Dacelo novaeguineae) was presented for evaluation of unilateral ocular lesions. The bird had a non-healing corneal ulcer and uveitis in the left eye. The combination...

Treatment of nonhealing corneal ulcers in 60 horses with diamond burr debridement (2010–2013)

To review the signalment, clinical characteristics, and outcome of horses with nonhealing corneal ulcers treated with diamond burr debridement (DBD); and to evaluate the role of ulcer duration, size and location, and bandage contact lens (BCL) placement on healing. From January 2012-April 2013, 60 horses were diagnosed with ulcers classified as nonhealing based on the presence of raised epithelial margins and duration of at least 7 days. Retrospective record review. Average age of included horses was 14.68 years, SD 8.17 years. There were three times as many males (45) as females (15), (χ12 = 15, P = 0.001). Forty-eight horses (80%) had nonhealing ulcers uncomplicated by associated corneal disease. In the remaining horses, associated corneal disease included esinophilic keratitis (10%), calcific band keratopathy (5%), endothelial decompensation (1.67%), habronemiasis(1.67%), and lid suture abrasion (1.67%). Average corneal ulcer duration prior to diamond burr debridement (DBD) was 29.0 days (n = 56). Ulcers occurred most commonly in the axial cornea (41%). Fifty-five of 60 horses (92%) healed with DBD. Healing time, defined as time to epithelialization following DBD, averaged 15.5 days, SD 9.32 days, and was not correlated with patient age or ulcer duration, location, or size prior to or following DBD. Healing time was significantly longer for eyes in which a BCL had been placed (n = 28, 19.0 days) than for eyes without a BCL (n = 32, 12.9 days), F(1,58) = 5.543, P = 0.02. DBD was considered a failure for five horses (8%). DBD may be an effective treatment for nonhealing corneal ulcers in horses.

Outcomes of Pars Plana Glaucoma Drainage Implant in Boston Type 1 Keratoprosthesis Surgery

Glaucoma drainage implantation in conjunction with Boston Type 1 Keratoprosthesis placement is a surgical option in controlling postoperative glaucoma. The purpose of this study is to report outcomes of combined pars plana vitrectomy and glaucoma drainage implantation with corneal patch graft in Boston Type 1 Keratoprosthesis patients. A retrospective review of patients who underwent pars plana glaucoma drainage implantation in combination with Boston Type 1 Keratoprosthesis was performed. Preoperative and postoperative parameters collected and analyzed included: visual acuity, intraocular pressure, number of glaucoma medications to achieve intraocular pressure control, bandage contact lens fit, and postoperative complications. Twenty eyes of 20 patients were identified; 95% had preoperative diagnosis of glaucoma, utilizing on an average 2.5 medications with an average intraocular pressure of 19.8 mm Hg (±6.3 mm Hg; range, 9 to 32.8 mm Hg). After placement of the pars plana glaucoma drainage implant, an average intraocular pressure of 19 mm Hg (±7.0 mm Hg; range, 8 to 30 mm Hg) by scleral pneumotonometry was achieved and 85% were deemed to have normal pressures by digital palpation. An average of 2.1 intraocular pressure-lowering medications were required on last follow-up. Average follow-up was 31.6 months (±17.4 mo; range, 12.3 to 71.6 mo). Two eyes required glaucoma drainage implant explantation: one eye due to endophthalmitis from a nonhealing corneal ulcer and the other eye due to corneal melt. None of our patients experienced conjunctival erosion over a pars plana positioned glaucoma drainage implant or tube. For the long-term management of glaucoma in keratoprosthesis patients, a posteriorly placed pars plana glaucoma drainage implant with corneal patch graft in conjunction with keratoprosthesis has a low risk of erosion and postoperative complications.

Repositioning of pedicle conjunctival flap performed for refractory corneal ulcer

A 50-year-old male was referred with a previous history of conjunctival flap (CF) for a nonhealing fungal corneal ulcer with extreme corneal thinning in the right eye. The peritomy for the CF extended from 6:30 to 9:30 clock h on the cornea. The CF was disengaged, peritomy area deepithelialized, and CF was repositioned. He later underwent penetrating keratoplasty and achieved 20/40 best corrected visual acuity. The authors present a new concept for surgically repositioning CF s to the original site immediately after healing of the corneal ulcer.

Sutureless Amniotic Membrane ProKera for Ocular Surface Disorders

To evaluate the indications and outcomes of sutureless amniotic membrane transplant (AMT; ProKera) in the management of ocular surface disorders. Chart review of patients who had ProKera (Bio-Tissue, Inc.) implantation for ocular surface disorders between June 2008 and May 2012 at 3 ophthalmology practices in Philadelphia, PA. The parameters evaluated included age, sex, indication for AMT, any other combined procedure, duration of retention of amniotic membrane, the effect of amniotic membrane on ocular surface healing, follow-up time, and complications. There were 35 eyes of 33 patients with a mean age of 68.2±19.5 years (range: 17-99 years). There were 25 male patients, and median follow-up was 110 days (mean: 164.6 days; range: 30-960 days). The indication for insertion of ProKera was nonhealing corneal ulcers of infective origin (group 1) in 9 eyes (25.7%), neurotrophic keratopathy (group 2) in 11 eyes (31.4%), chemical injury (group 3) in 5 eyes (14.3%), and other indications (group 4) in 10 eyes (28.6%). Complete or partial success was seen in a total of 44%, 64%, 80%, and 70% eyes in groups 1 to 4, respectively. Discomfort with the device was seen in 6 (17.1%) of 35 eyes, and recurrence of primary pathologic condition occurred in 5 (14.3%) of 35 eyes. ProKera treatment is easy to use and reasonably well tolerated, with moderate success in corneal ulcers and encouraging results in acute moderate chemical injury. Recurrence of primary pathologic condition is seen particularly associated with neurotrophic keratitis and dry eye syndrome.

Role of multilayered amniotic membrane transplantation for the treatment of resistant corneal ulcers in North India

To study the role of multilayer amniotic membrane transplantation (AMT) in the treatment of non-healing corneal ulcers. This study included 28 patients with non-healing bacterial corneal ulcers. AMT was performed using the 'overlay on-inlay' technique'. The outcome was assessed in terms of best corrected visual acuity (BCVA), corneal re-epithelization, graft/tissue edema and vascularity, graft melting, graft retraction, infection of graft and surface necrosis. The success rate of ulcer healing was 82.1 % (23 patients) 1 month after surgery, 78.5 % (22 patients) after 3 months and 75 % (21 patients) after 6 months. In the early post-operative period, BCVA deteriorated in all patients (perception of light to hand movement) but improved later. In 26 of the 28 patients (92.8 %) graft retraction occurred after 1 month and neovascularization was seen in 17 of the 28 patients (60.7 %). Multilayer AMT using an overlay on-inlay graft in non-healing bacterial corneal ulcers is a good option in terms of ulcer healing and symptomatic improvement.

Evaluation of the effects of age and pituitary pars intermedia dysfunction on corneal sensitivity in horses

To determine effects of age and pituitary pars intermedia dysfunction (PPID) on corneal sensitivity in horses. 20 adult horses allocated into 3 groups (PPID group, old [> 15 years old] horses with PPID [n = 5]; old group, old [> 15 years old] horses without PPID [9]; and young group, young [≤ 10 years old] horses without PPID [6]). All horses with PPID had hirsutism and abnormal fat deposition or laminitis; none of the old or young horses had hirsutism, abnormal fat deposition, or laminitis. A Cochet-Bonnet aesthesiometer was used to measure the corneal touch threshold (CTT) in both eyes of each horse. The nylon monofilament was applied at a maximum length of 60 mm to the central region of the cornea and length was decreased by 5-mm increments until a consistent blink response was elicited. Tear production was assessed in all eyes via the Shirmer tear test (STT). Mean ± SD CTT was significantly greater for young horses (47.50 ± 4.52 mm) than for horses in the old (28.06 ± 5.72 mm) and PPID (21.5 ± 3.37 mm) groups. Old horses had significantly higher CTT values than did horses with PPID. The STT values were within the reference range for all groups and did not differ significantly among groups. Corneal sensitivity decreased with both age and PPID. Because decreased corneal sensitivity is associated with impaired wound healing, increasing age and PPID may increase the risk for nonhealing or recurrent corneal ulcers in horses.

New insight into non-healing corneal ulcers: iatrogenic crystals

To characterise and correlate crystalline precipitations implicated in non-healing corneal ulceration in two patients with a previous history of acanthamoeba keratitis. Persistence of acanthamoeba and secondary bacterial infection was excluded with negative corneal scrapes. Confocal microscopy identified crystal-like deposits within the corneal stroma. To investigate possible precipitating combinations, all concurrent treatments at the time of presentation were mixed in wells, with observation of precipitate formation. Precipitates were observed with phase-contrast microscopy, and subsequently characterised via crystallography techniques and electrospray ionisation mass spectrometry. Combinations of dexamethasone 0.1% minims and chlorhexidine gluconate 0.2% formed an amorphous material characterised by electrospray ionisation mass spectrometry as an insoluble chlorhexidine salt. Combinations of chloramphenicol drops and timolol 0.5% formed a crystal identified via X-ray crystallography as santite (K(B₅O₆(OH)₄).(H₂O)₂). This is a borate mineral identified in nature, arising from thermal springs, but never reported in biological tissues. Clinical improvement was observed following the cessation of the implicated precipitating combinations. Our observations suggest iatrogenic precipitate formation, with a potential deleterious effect upon healing. The substrates for these precipitates include several frequently prescribed topical ophthalmic treatments. These findings shed new light on the aetiopathogenesis of non-healing corneal ulceration, and have broad implications on topical prescribing for this challenging condition.