Corneal Anesthesia Research Articles

Synthesis and local anaesthetic activity of 2-substituted-N-(2-diethylaminoethyl)-acetamides.

The synthesis of 2-substituted-N-(2-diethylaminoethyl)acetamide oxalates (6a, 6b) and the evaluation of their in vivo local anaesthetic activities are described. The compounds 6a and 6b were obtained starting from 4-acetamidophenol and 1-naphthol, respectively. The in vivo local anesthetic activity was evaluated by infiltration anaesthesia, sciatic nerve block and corneal anaesthesia models. N-(2-Diethylaminoethyl)-2-(naphthalen-1-yloxy)acetamide oxalate (6b) was found to have potency, onset and duration of action comparable to that of lidocaine (2) (lidocaine hydrochloride, CAS 6108-05-0). Procaine (1) (procaine hydrochloride, CAS 51-05-8) was also used for comparison. Dissociation constants (pKa) of compounds 5a and 5b (2-substituted-N-(2-diethylaminoethyl)acetamide) have been determined to be 8.9 and 8.6, respectively.

Therapeutic Dosing of Fingolimod (FTY720) Prevents Cell Infiltration, Rapidly Suppresses Ocular Inflammation, and Maintains the Blood-Ocular Barrier

Fingolimod (FTY720) is an FDA-approved therapeutic drug with efficacy demonstrated in experimental models of multiple sclerosis and in phase III human multiple sclerosis trials. Fingolimod prevents T-cell migration to inflammatory sites by decreasing expression of the sphingosine-1 phosphate receptor normally required for egress from secondary lymphoid tissue. As a preclinical model of human uveitis, experimental autoimmune uveoretinitis permits assessment of immunotherapeutic efficacy. Murine experimental autoimmune uveoretinitis is induced by activation of retinal antigen-specific CD4(+) T cells that infiltrate the eye. High-dose fingolimod treatment administered before disease onset reduces ocular infiltration within hours of administration and suppresses clinicopathologic expression of experimental autoimmune uveoretinitis. In the present investigation of the efficacy of fingolimod treatment for established disease, single-dose treatment was effective and immunosuppressive ability was maintained through a dose range, demonstrating significant and rapid reduction in CD4(+) cell infiltration at clinically relevant therapeutic doses of fingolimod. A repeated-treatment regimen using a dose similar to that in current multiple sclerosis patient protocols significantly reduced infiltration within 24 hours of administration; importantly, repeated doses did not compromise the vascular integrity of the blood-ocular barrier. On withdrawal of fingolimod, drug-induced remission was lost and recrudescence of clinical disease was observed. These results support a strong therapeutic potential for fingolimod as an acute rescue therapy for the treatment of ocular immune-mediated inflammation.

Ramos‐Arroyo syndrome: Confirmation of an entity

In 1987, Ramos-Arroyo et al. described a family with a previously unreported combination of features, which included corneal anesthesia, short stature, sensorineural deafness, learning difficulties, and a characteristic facial appearance. The family was reviewed in 2008 and additional features were noted. The name Ramos-Arroyo syndrome was proposed. The condition can be delineated by corneal anesthesia, absence of the peripapillary choriocapillaris and retinal pigment epithelium, bilateral sensorineural hearing loss, unusual facial appearance, persistent ductus arteriosus, Hirschprung disease, short stature, and intellectual disability. No other patient has been described since. Here, we report on a 5-year-old girl with features consistent with Ramos-Arroyo syndrome. We propose an overlap of this condition with dysautonomia syndromes.

Conjunctivitis and ulcerative keratitis secondary to conjunctival plant foreign bodies in a herd of alpacas (Lama Pacos)

To describe six cases of conjunctivitis and ulcerative keratitis secondary to plant foreign bodies from weed-contaminated grass hay which were lodged within the temporal conjunctival fornix in a herd of alpacas. A total of 21 alpacas from the same farm developed blepharospasm and mucopurulent ocular discharge. Six of the 21 were evaluated at the University of Tennessee College of Veterinary Medicine within a 2-week period. The six animals evaluated received an ophthalmic examination including slit-lamp biomicroscopy, fluorescein staining, and topical corneal anesthesia for foreign body removal when necessary. Six animals had conjunctivitis characterized by hyperemia and mucopurulent discharge. Five animals had superficial ulcerative keratitis with intense corneal neovascularization and edema. In all cases, the keratitis was located at the temporal limbus. Seven plant foreign bodies were observed and were removed following topical corneal anesthesia in five animals. The plant seeds were identified as three common weed species found in orchard grass hay. Complete resolution of all clinical signs was achieved with foreign body removal and medical therapy. Fan-shaped temporal corneal ulcers may signify the presence of conjunctival foreign bodies in alpacas. Plant foreign bodies should be considered in addition to ocular infection when multiple animals of a herd are affected as outbreaks may occur with weed-contaminated hay.

Duration of corneal anaesthesia following multiple doses and two concentrations of tetracaine hydrochloride eyedrops on the normal equine cornea

There is a clinical impression that tetracaine hydrochloride (THCl) eyedrops is a suitable topical anaesthetic in horses. To determine the duration of corneal anaesthesia following instillation of multiple doses and 2 concentrations of THCl in 10 healthy horses. The corneal touch threshold (CTT) was determined, in both eyes, before (basal CTT) and after application of one drop of 0.5% THCl, 2 drops at a 1 min interval of 0.5% THCl or one drop of 1% THCl. CTT was measured in mm every 5 min until complete recovery of the basal CTT. Treatments were separated by an interval of at least one week. Corneal sensitivity was significantly reduced from baseline values for 30, 60 and 50 min after application of one drop of 0.5% THCl, 2 drops of 0.5% THCl and one drop of 1% THCl, respectively. Mean maximal anaesthetic effects, corresponding to a CTT of 0 mm, lasted 5.5, 16 and 15.25 min and maximal anaesthetic effect was present in 55, 90 and 80% of eyes, 5 min after application of one drop of 0.5% THCl, 2 drops of 0.5% THCl and one drop of 1% THCl, respectively. The application of a second drop or the use of more concentrated eyedrops significantly increases duration of both anaesthesia and maximal anaesthetic effect. Duration of corneal anaesthesia following tetracaine instillation was established enabling a better use when performing diagnostic and therapeutic procedures. Comparison of tetracaine with other ocular anaesthetics needs to be published in the future.

Dry Eye Reversal and Corneal Sensation Restoration With Topical Naltrexone in Diabetes Mellitus

To determine if topical application of naltrexone hydrochloride (NTX), an opioid antagonist, restores tear production and corneal sensation in rats with diabetes mellitus. Type 1 diabetes was induced with streptozotocin in rats. Tear production was measured by the Schirmer test, and corneal sensitivity, by an esthesiometer. Eye drops of 10(-5)M NTX or sterile vehicle were administered either once only or 4 times a day for 1 or 5 days; a single drop of insulin (1 U) was given once only. Dry eye and corneal insensitivity were detected in the diabetic rats beginning 5 weeks after streptozotocin injection. One drop of NTX or 4 times a day for 1 or 5 days reestablished tear production and corneal sensitivity within 1 hour of administration. The reversal of dry eye lasted for up to 2 to 3 days depending on drug regimen, but restitution of corneal sensation lasted for 4 to 7 days. Topical application of 1 eye drop of insulin restored corneal sensitivity within 1 hour and lasted for at least 2 days. In contrast, 1 eye drop of insulin did not increase tear production at 1, 24, or 48 hours compared with diabetic animals receiving sterile vehicle. Topical treatment with NTX normalizes tear production and corneal sensitivity in type 1 diabetic rats. Topical application of NTX to the ocular surface may serve as an important strategy for treating dry eye and corneal anesthesia in diabetes. Its effect, if any, in other forms of decreased corneal sensitivity and/or dry eye should be investigated.

Septo-optic dysplasia with bilateral congenital corneal anesthesia

Septo-optic dysplasia, or de Morsier syndrome, is characterized by optic nerve hypoplasia with an absent septum pellucidum and/or pituitary abnormalities. Congenital corneal anesthesia is a rare disorder that has been associated with many neurological disorders. Here we present a patient with both conditions who was successfully treated with permanent lateral tarsorrhaphy and aggressive lubrication. To our knowledge, congenital corneal anesthesia has not been reported in association with septo-optic dysplasia. The purpose of this report is to make pediatric ophthalmologists aware of a potential association since the diagnosis of congenital corneal anesthesia is often difficult and delayed.

Ocular Manifestation in Treated Multibacillary Hansen's Disease

To report the prevalence of ocular morbidity in patients with treated multibacillary Hansen's disease (HD) using modern ophthalmic diagnostic techniques in a rural community endemic for HD. Cross-sectional, observation study. All patients with multibacillary HD who had completed their multidrug therapy and who resided in 4 defined geographical areas in Vellore, Tamil Nadu, India. All participants underwent a complete eye examination that included slit-lamp examination, esthesiometry, gonioscopy, applanation tonometry, and dilated fundus examination, including a stereobiomicroscopic examination of the fundus at an ophthalmic center set up for that purpose. Glaucoma suspects underwent automated perimetry using a Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA). The prevalence of various ocular disease parameters were reported as mean value with 95% confidence interval. The difference of disease prevalence between various leprosy groups was compared using an unpaired t test. The association between eye symptoms and potentially sight-threatening complications was analyzed using the chi-square test. Three hundred eighty-six of the 446 patients with multibacillary HD residing in the defined areas were evaluated. Four patients (1.04%; 95% confidence interval [CI], 0.0%-2.0%) were bilaterally blind; 33 (8.55%; 95% CI, 5.8%-11.3%) had unilateral blindness. Mean intraocular pressure was 12 mmHg (standard deviation, 4.1 mmHg), and prevalence of glaucoma was 3.6% (95% CI, 1.8%-5.5%). Potentially sight-threatening (PST) pathologic features (corneal anesthesia, lagophthalmos, uveitis, scleritis, and advanced glaucoma) were present in 10.4% (95% CI, 7.4%-13.4%) of patients. Significant cataracts occurred 3 times more frequently in those with polar lepromatous leprosy. The odds ratio for PST pathology in the presence of patient-reported symptoms (pain, redness, inability to close eye, burning, and irritation) was 2.9 (95% CI, 1.34-6.26). Patients who have completed treatment for multibacillary HD continue to have significant ocular morbidity. A history of specific eye symptoms can be the basis for referral by field staff.

Hearing preservation in a case of acoustic Schwannoma

Acoustic Schwannomas constitute 70-80% of cerebello-pontine angle (CP angle) tumors [1]. These tumors arise from the vestibular component of the eighth nerve [2]. The clinical presentation in these cases is usually with tinnitus followed by hearing loss [3]. They may later involve seventh, fifth and lower cranial nerves and cerebellar and brain stem compression syndromes, as the tumor grows. Hydrocephalus due to fourth ventricular distortion is a usual accompaniment of larger CP angle tumors. The surgical extirpation of these lesions was associated with a prohibitive mortality till the era of Harvey Cushing and Dandy [4], who brought down the surgical mortality from 70% to 15%. The morbidity of CP angle tumor surgery remained considerable with facial palsies, often compounded with the corneal anaesthesia due to fifth cranial nerve involvement resulting in corneal ulceration in addition to the cosmetic deformity. With refinements in technology, facial nerve conservation became a reality with many modern series claiming anatomical conservation of the facial nerve in upto 98% of cases and functional conservation in a large percentage of these cases [5]. Conservation of hearing is however rarely achieved even with all available technological innovations and monitoring techniques. We present a case of acoustic schwannoma which presented atypically and in whom hearing could be partially conserved after resection by a retromastoid approach.

Prolonged corneal anaesthesia by proxymetacaine hydrochloride detected by a thermal cooling stimulus

To assess the duration, depth and recovery time of anaesthesia produced by 0.5% proxymetacaine hydrochloride (proparacaine), using a thermal cooling stimulus. Seventeen non-contact lens-wearing subjects were recruited (mean age=26+/-3.6 years, range=23-39; blue iris=8, brown iris=9). Central corneal sensitivity was measured in the right eye of each patient to establish a baseline, before 20microl of either 0.5% proxymetacaine hydrochloride (p) or 0.9% unpreserved saline (s) was instilled under four experimental conditions (right eye-left eye): p-p, p-s, s-p, s-s. Corneal sensitivity was re-measured at 2, 5, 10, 15, 20, 30, 45 and 60min post-instillation. The onset of anaesthesia was observed at 2min (Wilcoxon, p<0.001), with the maximum anaesthesia occurring at 15min (Wilcoxon, p<0.001). Recovery of corneal sensitivity to baseline levels did not occur by 60min (Wilcoxon, p<0.001). No difference in onset time, depth of anaesthesia, or recovery time was noted between the blue and brown iris subjects (Mann-Whitney, p>0.05). Although the anaesthetic effect of 0.5% proxymetacaine hydrochloride continues for more than 60min, this finding does not alter current clinical practice. The extended duration, however, is of relevance to studies that use corneal anaesthesia to investigate the role of corneal nerves in the blink mechanism.

Corneal Neurotization: A Novel Solution to Neurotrophic Keratopathy

This study was designed to evaluate the efficacy of direct corneal neurotization using contralateral supraorbital and supratrochlear nerves in patients with unilateral facial palsy and corneal anesthesia. A novel surgical procedure in which these donor nerve branches are inserted at the contralateral anesthetic corneal limbus for sensory neurotization is described. The charts of six patients were reviewed thoroughly to evaluate changes in corneal sensibility following surgery for direct corneal neurotization. Visual acuity, blink reflex, donor deficit, synesthesia, long-term corneal health, and several psychosocial measures and overall patient satisfaction with the procedure are reported. Six patients with an average denervation time of 7.00 +/- 8.56 years before surgery were followed for an average period of 16.3 +/- 2.42 years. All six eyes showed improvement of corneal sensibility, visual acuity, and corneal health and remained free of ulcers or other signs of advancing neurotropic keratopathy. Average corneal sensibility improved from 2.00 +/- 4.47 mm before surgery to 278.00 +/- 226.00 mm following corneal neurotization (p < 0.016). Direct neurotization of the cornea using the contralateral supraorbital and supratrochlear branches of the ophthalmic division of the trigeminal nerve appears to be an effective method of restoring the corneal sensibility in patients with unilateral facial palsy and anesthetic cornea. This technique preserves ocular anatomy and cosmesis and restores function by improving corneal health and visual acuity.

Pulsed Radiofrequency Treatment of the Supraorbital and Supratrochlear Nerve in a Case of Trigeminal Neuralgia -A case report-

Pharmacological management is the first choice for treatment of the trigeminal neuralgia patients; however, if this mode of treatment fails a minimally invasive procedure should be performed. One of the most commonly used procedures is conventional radiofrequency lesioning of the Gasserian ganglion. Despite its popularity and success rate, this technique has disadvantages such as diminished corneal reflex, masseter weakness, numbness and anesthesia dolorosa. As a result, many studies have been conducted in an attempt to find a better method of treating trigeminal neuralgia. We report here a case of a trigeminal neuralgia patient that was treated with pulsed radiofrequency lesioning of the supraorbital and supratrochlear nerve due to pain in the frontal head that was refractory to the pharmacological treatments. Following the procedure, the Visual Analogue Scale score for pain decreased to 1−2/10 and the pain relief persisted for 7 months. These results indicate that pulsed radiofrequency treatment of the peripheral nerve may be useful for trigeminal neuralgia patients that do not respond to pharmacological treatments.

Type I Boston keratoprosthesis with cataract extraction and intraocular lens placement for visual rehabilitation of herpes zoster ophthalmicus: the “KPro Triple”

Management of corneal scarring following herpes zoster ophthalmicus (HZO) is challenging due to the dense corneal anesthesia that results from viral damage to the subepithelial nerve plexus. These patients have...

Evaluation of duration of corneal anesthesia induced with ophthalmic 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in clinically normal horses

To measure duration of corneal anesthesia and time and degree of maximal anesthetic effect of 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in horses. 10 clinically normal adult horses. Baseline corneal touch threshold (CTT) was measured in millimeters for 1 randomly selected eye of each horse by use of the aesthesiometer by applying the filament to the cornea at maximum length (60 mm) and decreasing in 5-mm increments until a consistent blink response was elicited. Following baseline CTT measurement, 0.2 mL of 0.5% proparacaine hydrochloride was instilled in the selected eye. The CTT was measured within 1 minute following proparacaine administration and every 5 minutes thereafter for 60 minutes. A mixed-model ANOVA with tested eye varying between subjects and measurement time varying within subject was used to test for main effects and any interaction between these factors. A contrast between means of baseline and each subsequent CTT identified the duration of corneal anesthesia as the time at which there was no difference from baseline. Maximal anesthetic effect occurred at the time with the lowest mean CTT. Duration of corneal anesthesia achieved by use of proparacaine was 25 minutes, and maximal anesthetic effect occurred within 5 minutes, although CTT never went to 0 in any horse at any time. Duration of corneal anesthesia in horses was shorter than in dogs, and degree of maximal effect was less than in cats and dogs, most likely because of increased sensitivity of the equine cornea, compared with corneal sensitivity in those species.

Evaluation of duration of corneal anesthesia induced with ophthalmic 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in clinically normal horses

Evaluation of duration of corneal anesthesia induced with ophthalmic 0.5% proparacaine hydrochloride by use of a Cochet-Bonnet aesthesiometer in clinically normal horses

Percutaneous Balloon Compression for the Treatment of Recurrent Trigeminal Neuralgia: Long-Term Outcome in 29 Patients

Objective: To analyze the long-term clinical outcomes and complication rates associated with percutaneous balloon compression (PBC) of the trigeminal ganglion in patients with recurrent trigeminal neuralgia (TN) who were treated surgically with procedures other than PBC. Methods: In this retrospective study, the authors reviewed the results of 29 patients who underwent 41 PBC procedures for recurrent TN between 1998 and 2006. Results: The overall mean length of follow-up was 49 months (range 1–101). Pain relief was immediate in 24 (83%) patients. There was no pain relief in 5 patients (17%). 2 patients were lost to follow-up. 12 (54.5%) of 22 patients remained pain-free during a mean follow-up period of 65 months (range 40–101). The other 10 patients (45.5%) who had immediate pain relief experienced recurrent pain, with a mean time to recurrence of 7.3 months (17 days to 38 months). PBC was repeated in 11 patients, and was performed a third time in 2 patients. Morbidities included minor dysesthesia (2 patients), masseter weakness (2 patients), corneal anesthesia (1 patient), anesthesia dolorosa (1 patient), and subarachnoid hemorrhage (1 patient with history of multiple myeloma). Conclusion: PBC is a useful treatment for patients with recurrent TN who have already been treated surgically. Long-term relief of pain in this subset of TN patients is achieved nearly half of the time with side-effect profiles similar to those reported in published data.

Effect of topical corneal anaesthesia on ocular response analyzer parameters: pilot study

The effect of topical corneal anaesthesia on corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal compensated IOP (IOPcc) was measured by ocular response analyzer (ORA). Observational, cross-sectional study. We examined both eyes of 23 healthy volunteers. Patients with external eye disease, previous refractive surgery, contact lenses or topical medication were excluded. ORA parameters were first measured in both eyes. Oxybuprocaïne 0.4% eye drop was instilled in the right eyes (RE) and physiologic saline in the left eyes (LE) as a control to rule out the lubrication effect. After 2 min, the ORA measurements were performed again. Goldmann applanation tonometry (GAT) was finally done. Data are expressed as mean +/- standard deviation (SD). The medians of the four CH, CRF, IOPg, and IOPcc values measured before and after instillation were compared by using Wilcoxon signed ranks tests for RE and LE. The mean age was 39.5 +/- 11.6 years. The mean GAT was 13.1 +/- 2.5 mmHg for RE and 12.8 +/- 2.5 mmHg for LE. In the RE, the respective values for the two sequences were IOPcc = 15.6 +/- 2.6 mmHg and 15 +/- 2.8 mmHg (P = 0.036); IOPg = 15.3 +/- 3.3 mmHg and 15.4 +/- 3.5 mmHg (P = 0.806); CH = 11 +/- 1.3 mmHg and 11.1 +/- 1.4 mmHg (P = 0.563); CRF = 11.1 +/- 1.8 mmHg and 10.9 +/- 1.9 mmHg (P = 0.053). In the LE, the respective values for the two sequences were IOPcc = 15.4 +/- 2.6 mmHg and 15.6 +/- 2.8 mmHg (P = 0.903); IOPg = 15.5 +/- 3.5 mmHg and 15.4 +/- 3.4 mmHg (P = 0.208); CH = 10.8 +/- 1.4 mmHg and 10.7 +/- 1.7 mmHg (P = 0.494); CRF = 10.7 +/- 1.8 mmHg and 10.7 +/- 2.2 mmHg (P = 0.626). Two minutes after instillation, topical corneal anaesthetic slightly decreases IOPcc and also-but not statistically significantly-CRF. We did not find any statistical significant difference in CH or IOPg before and after topical corneal anaesthesia. Further investigation with more patients should be advised.

The Boston Scleral Lens in the treatment of pediatric patients

To report the use of a custom-designed, fluid-ventilated, gas-permeable scleral lens in the treatment of patients under 13 years of age. We retrospectively reviewed the medical records of all patients under 13 years of age who were fitted with the Boston Scleral Lens at the Boston Foundation for Sight from January 1996 through June 2006. Age, sex, ophthalmic diagnosis, systemic diagnosis, prior surgical intervention, complications, lens fit and wearing failures, and duration of lens use are reported. Boston Scleral Lenses were fitted in 47 eyes of 31 patients referred after failure of conventional therapy. Patients ranged in age from 7 months to 12.92 years (mean, 7.75 years) at time of fitting. There were 16 girls and 15 boys in this group. The mean duration of documented scleral lens use was 24 months (range, 0-85 months). A broad range of refractive and ocular surface disorders was treated with this modality, with the vast majority of patients having ocular surface disease (27/31, 87%) rather than refractive disorders (4/31, 13%). Congenital corneal anesthesia syndromes and Stevens-Johnson syndrome each accounted for over one-third of the patients. The Boston Scleral Lens is a custom-designed, fluid-ventilated, rigid gas-permeable scleral lens that vaults the cornea retaining a pool of oxygenated artificial tears over the corneal surface. The Boston Scleral Lens is a treatment option, after failure of conventional therapy, for a broad range of ocular surface and refractive disorders in the pediatric age group. Pediatric ophthalmologists should be aware of this treatment modality, particularly in the management of severe ocular surface disease.

Ramos‐Arroyo syndrome: Long‐term follow‐up of previously reported family

Here we report on a family with corneal anesthesia, absence of the peripapillary choriocapillaris and retinal pigment epithelium, bilateral sensorineural hearing loss, unusual facial appearance, persistent ductus arteriosus, Hirschsprung disease, and moderate mental retardation. The first two generations of this family were reported previously by Ramos-Arroyo et al. [Ramos-Arroyo et al., 1987]. Two further affected individuals have been born into this family and we have observed additional manifestations not previously reported that appear to be part of this syndrome. The differential diagnosis of the condition is also discussed. We think this is a distinct autosomal dominant syndrome with variable expressivity, and have named the disorder the Ramos-Arroyo syndrome.

Boston Keratoprosthesis Treatment of Herpes Zoster Neurotrophic Keratopathy

The successful use of the Boston keratoprosthesis in a severely inflamed ulcer in herpes zoster neurotrophic keratopathy. Approximately 10% to 20% of patients with herpes zoster will develop herpes zoster ophthalmicus (HZO). Antiviral medication forms the foundation of pharmacologic treatment for acute herpes zoster, but management of HZO is supplemented with topical and systemic antimicrobials and corticosteroid agents as well as surgical interventions. However, HZO is associated with poor healing, as evidenced by a high occurrence of ulceration, superinfection, and surgical failure. A 95-year-old man was referred for corneal edema in the right eye. There was a history of acute herpes zoster in the right eye 10 months previously. Slit-lamp examination revealed lagophthalmos, ectropion, total corneal anesthesia, and marked inferior corneal edema. Despite surgical repair of all lid abnormalities and aggressive lubrication and management of rosacea blepharitis, the corneal surface remained unhealthy. Four months later, the patient presented with an inflamed hypopyon ulcer, culture positive for abundant Pseudomonas and Candida albicans. The ulcer progressed to descemetocele in the face of aggressive antimicrobial therapy, vision was light perception (LP), and perforation became imminent. A Boston keratoprosthesis was used to replace the severely damaged cornea, and extracapsular cataract extraction of a mature cataract was also performed. One week after surgery, the inflammation was almost entirely resolved, and cultures of the host button were negative for any organisms. Vision gradually increased from LP to 20/60 over the ensuing 4 months. The Boston keratoprosthesis procedure successfully salvaged and restored vision in this high-risk herpes zoster eye in which standard keratoplasty would almost certainly have failed.