In Vivo Confocal Microscopy of Stromal Lenticule Addition Keratoplasty for Advanced Keratoconus

PURPOSE

To investigate the in vivo corneal microscopic changes after femtosecond laser-assisted stromal lenticule addition keratoplasty in keratoconus by means of in vivo confocal microscopy.

METHODS

Patients affected by advanced keratoconus were included in the study. Negative meniscus-shaped stromal lenticules, produced with a femtosecond laser (VisuMax; Carl Zeiss Meditec) from eye bank corneas were transplanted into a stromal pocket dissected in the recipient cornea at a depth of 120 µm. In vivo confocal microscopy was performed during the 12-month follow-up to investigate changes of the corneal and lenticule structure.

RESULTS

Ten patients were enrolled in the study. No changes of the dendritic cell population were documented during the follow-up period. Mild edema and stromal keratocyte activation gradually decreased during the first month. Subbasal nerve density returned to preoperative values after 6 months. Donor-recipient interfaces appeared hyperreflective but gradually improved over time with significantly reduced reflectivity after 3 months. No evidence of stromal inflammatory cell migration or matrix opacification was observed. Endothelial and keratocyte density remained stable over time. A variable degree of stromal radially distributed folds, not visible on biomicroscopy, was observed in the lenticule and in the posterior recipient stroma.

CONCLUSIONS

Stromal lenticule addition keratoplasty produces transitory nerve plexus density reduction and minor inflammatory reaction that rapidly decreases during the first month. Donor-recipient interface reflectivity is comparable to a femtosecond laser refractive procedure with no sign of stromal opacification or stromal rejection in 1 year of follow-up. [J Refract Surg. 2020;36(8):544-550.].

Long-term Effects of LASIK on Corneal Innervation and Tear Neuropeptides and the Associations With Dry Eye

PURPOSE

To investigate the associations between dry eye, corneal nerves, and tear neuroptides in dry eye after LASIK.

METHODS

A single visit cross-sectional study was performed. Twenty participants who had LASIK more than 12 months prior and 20 healthy participants were recruited. Ocular comfort, tear functions, ocular surface sensitivity, basal tear collection, and corneal nerve morphology assessments were conducted. Tear substance P and calcitonin gene-related peptide (CGRP) concentrations were determined using ELISAs. Differences in variables between groups were examined using an independent t test or Mann-Whitney U test, as appropriate. Associations between variables in the post-LASIK group were examined using a Spearman's correlation test. A P value of less than .05 was considered significant.

RESULTS

Central corneal nerve morphology parameters were all altered in the post-LASIK group (P < .05). Higher ocular discomfort (P = .01), tear CGRP concentration (P = .001), and conjunctival sensitivity (P < .009) were found in the post-LASIK group. There was a positive association between dry eye symptoms and superior corneal sensitivity (P = .51, P = .02) and tear substance P concentration (P = .52, P < .03).

CONCLUSIONS

This study provides evidence of the association between tear neuropeptides, conjunctival sensitivity, and symptoms in symptomatic patients after LASIK. The differences in nerve morphology, neuropeptide, and ocular surface sensitivity between symptomatic and asymptomatic patients after LASIK are required to better understand the mechanism of dry eye after LASIK. [J Refract Surg. 2016;32(8):518-524.].

Effects of corneal nerve density on the response to treatment in dry eye disease

PURPOSE

To evaluate whether levels of corneal subbasal nerve fiber length (SNFL) in dry eye disease (DED) could prognosticate the level of improvement in signs and symptoms after treatment.

DESIGN

Phase IV, double-masked, randomized clinical trial.

PARTICIPANTS

Sixty patients with meibomian gland dysfunction-associated DED and 27 age-matched controls.

METHODS

Patients with DED were randomized to receive topical artificial tears, loteprednol etabonate 0.5%, or loteprednol etabonate 0.5%/tobramycin 0.3% twice daily for 4 weeks. At baseline, in vivo confocal microscopy of central cornea was performed in both eyes. Patients with DED were divided into 2 subgroups: those with low baseline SNFL and those with near-normal baseline SNFL for this purpose (the cutoff point: the mean SNFL in controls minus 2 standard deviations). Clinical signs and symptoms at baseline and after 4 weeks of treatment were compared between the subgroups with low and near-normal SNFL for all therapeutic groups.

MAIN OUTCOME MEASURES

Symptom questionnaires, corneal fluorescein staining (CFS), conjunctival staining with lissamine green, tear break-up time, Schirmer's test, and SNFL.

RESULTS

In patients with DED, baseline SNFL (17.06±5.78 mm/mm(2)) was significantly lower than in controls (23.68±3.42 mm/mm(2), P = 0.001). In the artificial tear and loteprednol groups, although no significant improvement in any sign or symptom was noted in patients with low baseline SNFL (<16.84 mm/mm(2)), subjects with near-normal baseline SNFL (≥16.84 mm/mm(2)) showed significant improvement in both symptoms and CFS score (all P < 0.05). In the loteprednol/tobramycin group, no significant change was evident for any sign or symptom in either subgroup of low or near-normal baseline SNFL.

CONCLUSIONS

Significant improvements in CFS and patient symptomatology after DED treatment were evident only in the subgroup with near-normal corneal SNFL. Consideration of SNFL may assist in explaining the variability of patients' response to DED therapy.

Effects of amino acids enriched tears substitutes on the cornea of patients with dysfunctional tear syndrome

PURPOSE

To evaluate the effect of aminoacid enriched artificial tears on the ocular surface of patients with dysfunctional tear syndrome (DTS).

METHODS

Forty patients were divided into two groups: group 1 treated for 90 days with sodium hyaluronate (SH) 0.15% 1 drop × 5 times/day; group 2 treated for 90 days with SH 0.15% + aminoacids mixture 1 drop × 5 times/day. Symptom score questionnaire, tear break-up time (TBUT), corneal fluorescein stain, Shirmer's I test and confocal microscopy were performed at baseline and after 30 and 90 days. Confocal images underwent morphometric analysis.

RESULTS

Both treatments improved symptoms after 1 month. Group 2 patients showed at 1 month an improvement of TBUT and corneal stain, maintained throughout the study. Also Shirmer's I test improved after 3 months. In group 1, an improvement of TBUT and corneal stain was observed after 3 months. The morphometric analysis of confocal images demonstrated at month 1 an improvement of nerve tortuosity in group 2; after 3 months both groups showed a significant improvement versus baseline. The epithelium showed, in both groups, a reduction in hyperreflective large cells starting from 1 month; the area of the cells was significantly reduced after 3 months, with a significant higher reduction in group 2. The perineural stromal opacity was significantly increased after 3 months, particularly in group 2.

CONCLUSION

This is the first study addressing corneal changes after amino acids administration in a DTS population. The treatment with amino acids enriched SH can be considered a useful tool in the treatment of DTS.

[Incomplete Horner's syndrome as a presenting sign of fourth ventricle ependymoma]

CASE REPORT

The case of 44 year old male patient with palpebral ptosis and trigeminal neuralgia as presenting sign of fourth ventricle ependymoma is reported. After surgical treatment, the patient developed a residual paresis of the sixth cranial nerve.

DISCUSSION

Horner's syndrome occurs due to an alteration of the sympathetic innervations of the eye and adnexa. Some tumours may be the cause, in our case an ependymoma of the fourth ventricle, which onset exceptionally with blepharoptosis and involvement of the ophthalmic division of trigeminal nerve, due to the proximity of these nerve fibres at the brainstem.

Pathologic epithelial and anterior corneal nerve morphology in early-stage congenital aniridic keratopathy

OBJECTIVE

To document the clinical and morphologic corneal findings in the early stages of congenital aniridic keratopathy in Swedish families.

DESIGN

Prospective, observational, comparative case series.

PARTICIPANTS

A total of 16 eyes of 16 subjects with congenital aniridic keratopathy and a clear central cornea, and 6 eyes from 6 healthy controls (unaffected relatives). Nine of the 16 eyes with aniridia came from 5 families with a documented familial history of aniridia.

METHODS

Detailed ophthalmic examinations included best spectacle-corrected visual acuity (BSCVA), tear film production, tear break-up time (BUT), corneal touch sensitivity, intraocular pressure measurement, ultrasound pachymetry, slit-lamp biomicroscopy, and laser scanning in vivo confocal microscopy (IVCM).

MAIN OUTCOME MEASURES

Confirmed stage of aniridic keratopathy, clinical parameters of cornea and tear film (visual acuity, sensitivity, corneal thickness, tear production, and BUT), and the morphologic status of corneal epithelium, sub-basal nerves, and limbal palisades of Vogt.

RESULTS

In early-stage aniridic keratopathy, BSCVA and tear BUT were reduced relative to controls (P < 0.001 for both), and corneal thickness was increased (P=0.01). Inflammatory dendritic cells were present in the central epithelium in aniridia, with significantly increased density relative to controls (P = 0.001). Discrete focal opacities in the basal epithelial region were present in 5 of 11 aniridia cases with an otherwise clear cornea. Opacities were associated with dendritic cells and harbored structures presumed to be goblet cells. Sub-basal nerves were extremely dense in 3 aniridia cases, and a prominent whorl pattern of nerves and epithelial cells was observed in 1 case. Normal limbal palisade morphology was absent in aniridia but present in controls.

CONCLUSIONS

Early-stage aniridic keratopathy is characterized by the development of focal opacities in the basal epithelium, altered sub-basal nerves, infiltration of the central epithelium by dendritic cells, tear film instability, and increased corneal thickness and degradation of limbal palisade architecture. These findings may help to elucidate the pathogenesis of aniridic keratopathy.

[Intraorbital schwannoma arising from the supraorbital nerve]

A 67-year-old man presented a three-month history of double vision and slight numbness at his right forehead. Neurological examination on admission demonstrated diplopia at lower gaze and mild hypesthesia at right frontal. MRI disclosed an extraconal cystic mass, centered over the superior rectus muscle, in the superior part of the right orbit. 3D-CT scan in bone window image showed an erosion of the right orbital roof. An operation was performed by a transcranial extradural anterior orbitotomy. It was noticed that the supraorbital nerve entered the cyst wall of the tumor. The mass was dissected from the surrounding intraorbital fat and was removed completely. Pathologically, diagnosis of schwannoma was made. Postoperatively, the diplopia diminished, although numbness at the right forehead remained. Orbital schwannomas constitute 1 to 4% of all orbital tumours. Identification of the nerve of origin of the tumours is difficult. Including this present case, only 11 cases of supraorbital nerve schwannoma, and only three cases of the tumour without neurofibromatosis, have been reported.

Corneal sensation and subbasal nerve alterations in patients with herpes simplex keratitis: an in vivo confocal microscopy study

PURPOSE

To study and correlate corneal sensation in patients with herpes simplex keratitis (HSK) with density and morphologic features of subbasal corneal nerves by in vivo confocal microscopy (IVCM).

DESIGN

Prospective, cross-sectional, controlled, single-center study.

PARTICIPANTS

Thirty-one eyes with the diagnosis of acute (n = 7) or chronic (n = 24) HSK and their contralateral clinically unaffected eyes were studied and compared with normal controls (n = 15).

METHODS

In vivo confocal microscopy (Confoscan 4; Nidek Technologies, Gamagori, Japan) and corneal esthesiometry (Cochet-Bonnet; Luneau Ophthalmlogie, Chartres, France) of the central cornea were performed bilaterally in all patients and controls. Patients were grouped into normal (> 5.5 cm), mild (> 2.5-5.5 cm), and severe (≤ 2.5 cm) loss of sensation.

MAIN OUTCOME MEASURES

Changes in corneal nerve density, total nerve number, main nerve trunks, branching, and tortuosity were evaluated after IVCM and were correlated to corneal sensation, disease duration, and number of recurrences.

RESULTS

Herpes simplex keratitis eyes, as compared with controls, demonstrated significant (P < 0.001) decrease in mean nerve density (448.9 ± 409.3 vs. 2258.4 ± 989.0 μm/frame), total nerve number (5.2 ± 4.5 vs. 13.1 ± 3.8), main nerve trunks (2.3 ± 1.6 vs. 4.7 ± 1.2), and nerve branches (3.2 ± 4.3 vs. 9.8 ± 3.3). In contralateral unaffected eyes, mean nerve density (992.7 ± 465.0 μm/frame), total nerve number (7.8 ± 3.3), and branches (4.5 ± 2.3) were decreased significantly as compared with controls (P < 0.002). Reduced nerve density, total nerve count, and main trunks in HSK eyes were correlated significantly with corneal sensation across all subgroups (P < 0.001). Nerve density decreased within days of infection and was correlated to frequency of episodes in patients with HSK (P < 0.02).

CONCLUSIONS

In vivo confocal microscopy revealed that the loss of corneal sensation in HSK correlates strongly with profound diminishment of the subbasal nerve plexus after herpes simplex virus infection. Surprisingly, the contralateral, clinically unaffected eyes also demonstrated a diminishment of the subbasal nerve plexus as compared with normal subjects, revealing bilateral nerve alteration in an apparently unilateral disease.

Corneal healing after riboflavin ultraviolet-A collagen cross-linking determined by confocal laser scanning microscopy in vivo: early and late modifications

PURPOSE

To assess early and late micromorphological modifications of cross-linked corneas in vivo by means of Heidelberg Retinal Tomography (HRT) II confocal microscopy.

DESIGN

Prospective nonrandomized open trial.

METHODS

Micromorphological examination of 44 cross-linked keratoconic corneas was performed in vivo by HRT II confocal laser scanning microscopy. Riboflavin ultraviolet (UV)-A-induced corneal collagen cross-linking (CXL) was performed according to the Siena protocol: pilocarpin 1% drops 30 minutes before, topical anesthesia with lidocaine 4% drops 15 minutes before irradiation, mechanical scraping of epithelium (9-mm-diameter area), preirradiation soaking for 10 minutes in riboflavin solution 0.1% (Ricrolin, Sooft, Italy) applied every 2.5 minutes for 30 minutes, 30 minutes exposure to solid-state UVA illuminator (Caporossi; Baiocchi; Mazzotta, X-linker, CSO, Italy), 8-mm-diameter irradiated area, energy delivered 3 mW/cm(2). All patients were examined by confocal scans preoperatively and at the following times after treatment: one, three, and six months, and one, two, and three years.

RESULTS

No damage to the limbal region was observed. Epithelial regrowth was complete after four days of soft contact lens bandage. The anatomy of the subepithelial plexus was restored one year after the operation with full corneal sensitivity. Increased density of extracellular matrix in late postoperative period indicated cross-linked collagen to a depth of 340 microm expressed by a late demarcation line.

CONCLUSION

In vivo confocal microscopy showed early and late modification of corneal microstructure after the treatment. The three-year stability of CXL recorded could be related to increased cross-links formation, synthesis of well-structured collagen and new lamellar interconnections.

Wavelike epitheliopathy after phacoemulsification: role of in vivo confocal microscopy

PURPOSE

The purpose of this report was to describe an uncommon wavelike epitheliopathy after phacoemulsification in a 59-year-old man with well-controlled diabetes mellitus.

METHODS

Retrospective case report.

RESULTS

A 59-year-old man with a history of well-controlled diabetes mellitus presented to us with irritation and blurring of vision in the right eye of 4-month duration after phacoemulsification with multifocal intraocular lens implantation. Slit-lamp examination revealed a wave-like epitheliopathy in the right cornea, extending nasally from the incision area. Corneal sensation was reduced. Confocal microscopy revealed reduced subbasal nerve plexus and unhealthy corneal epithelium. Topical application of preservative-free lubricants was advised. On follow-up examinations, it was observed that the disappearance of the epitheliopathy correlated with the regeneration of the nerve plexus, as shown by the in vivo confocal microscopy findings.

CONCLUSIONS

This is an isolated case report of a wavelike epitheliopathy after phacoemulsification. The regeneration of the subbasal nerve plexus correlating with the disappearance of the epitheliopathy suggests an element of neurotrophic corneal damage. Other probable mechanisms are discussed along with the in vivo confocal microscopy findings.

Comparative in vivo high-resolution confocal microscopy of corneal epithelium, sub-basal nerves and stromal cells in mice with and without dry eye after photorefractive keratectomy

BACKGROUND

The present study compares, using a new-generation high-resolution in vivo confocal microscope, the epithelial morphology, sub-basal nerves and stroma in two groups of mice: one exposed to normal conditions (NC) and the other to a desiccating environment (DE), following photorefractive keratectomy (PRK) with mechanical epithelial scraping.

METHODS

Twenty-four 4- to 8-week-old female Balb/C mice were used in this study. Twenty mice underwent bilateral corneal epithelial scraping using an electric brush prior to PRK. Then, the mice were divided in two groups: 10 mice were placed in NC. The other 10 mice were exposed to a DE for 2 weeks. Four mice served as controls. Corneas were analysed in vivo using the Rostock Cornea Module of the Heidelberg retina tomograph II. For all eyes, 20 confocal microscopic images of each layer, that is, the superficial and basal corneal epithelium, Bowman's layer, anterior and posterior stroma and the endothelium, were recorded. Epithelial and stromal cell densities and sub-basal and stromal nerves were measured and compared.

RESULTS

There was a higher density of superficial epithelial cells in the DE group (693 +/- 148 cells/mm(2) in NC group and 443 +/- 128 cells/mm(2) in DE group; Mann-Whitney U-test; P = 0.05). Higher number of basal cells were observed in the DE group. Its density was 986 +/- 198 cells/mm(2) in NC and 1598 +/- 280 cells/mm(2) in DE group (Mann-Whitney U-test; P < 0.05). Significantly higher number of reflective structures were noted within the stroma without clearly visible nuclei in the DE group compared with the NC eyes. Additionally, higher number of beads, nerve sprouts and higher tortuosity of sub-basal nerves were observed in the DE group. No difference was observed in the endothelial cell density between the groups.

CONCLUSION

Exposure of corneas to a DE after PRK with previous mechanical epithelial scraping increases epithelial turnover and is associated with a higher number of reflective structures in the stroma. Additionally increased nerve beading, nerve sprouts and tortuosity of sub-basal nerves were observed in the DE group, possibly directed to repair the alterations observed at the epithelial level.

[Primary open angle glaucoma. Morphological bases for the understanding of the pathogenesis and effects of antiglaucomatic substances]

The pathogenesis of glaucomatic illnesses is poorly understood. An increase in ocular pressure can be caused by an increase in the secretion of aqueous humour or a reduction in its outflow. In the elderly, outflow is reduced while at the same time less aqueous humour is produced. This balance is easily disturbed, so that age represents a risk factor for glaucoma in addition to increased ocular pressure. Therapeutic possibilities involve, on the one hand, reducing the secretion of aqueous humour, for example using, beta blockers, carbonic anhydrase inhibitors and clonidine. On the other hand, aqueous humour outflow can also be influenced by drugs. Conventional outflow is increased by the administration of miotics. The uveoscleral outflow can be increased by prostaglandin derivates. Drugs which only influence trabecular outflow are not yet available. Future therapeutic possibilities involve new aspects of the pathophysiology, e.c. the use of growth factors, free radical scavenging enzymes and choroidal blood flow.

The Cornea in Sjögren’s Syndrome: An In Vivo Confocal Study

PURPOSE

To analyze the in vivo morphology of corneal cells and nerves in dry eye associated with primary (SSI) and secondary (SSII) Sjögren's syndrome and to study its relationship with the clinical evaluation.

METHODS

Thirty-five patients with SS and 20 age- and gender-matched control subjects were studied. Confocal microscopy was used to investigate corneal thickness, epithelial and stromal cellular density, and subbasal plexus morphology.

RESULTS

Corneal central thickness was 514.74 +/- 19.85 microm in the SS group and 550 +/- 21.46 microm in the control group (P < 0.0001, t-test); stromal central thickness was 456.62 +/- 18.05 microm in the SS group and 487.35 +/- 20.40 microm in the control group (P < 0.0001). The density of the superficial epithelial cells in the SSI and SSII groups was 965.40 +/- 96.00 and 999.80 +/- 115.67 cells/mm(2), respectively, and 1488.55 +/- 133.74 cells/mm(2) in the control group (P < 0.001, ANOVA). The number of subbasal nerves was 3.34 +/- 0.76 in the SS group and 5.10 +/- 0.79 in the control group (P < 0.0001, t-test). The average grade of nerve tortuosity was 2.62 +/- 0.94 in the SS group and 1.20 +/- 0.70 in the control group (P < 0.0001). Statistically significant correlations were found between clinical data and confocal microscopy data.

CONCLUSIONS

Corneal thickness, cells, and nerves show morphologic changes in patients with dry eye associated with SS. The in vivo confocal study of these alterations may be important in better understanding the complexity of the ocular surface morphofunctional unit and the potentials of therapeutic approaches for the control of the phlogistic process and neuroprotection.

Papillary endothelial hyperplasia of the orbit: report of a case highlighting a pitfall on fine needle aspiration biopsy

BACKGROUND

Papillary endothelial hyperplasia (PEH) is an unusual form of thrombus organization that occurs predominantly in the extremities, including the head and neck. However, it is rare in the orbit/ocular region. Although the histologic features of PEH have been well described, the cytologic diagnosis remains difficult.

CASE

A 63-year-old man presented with a left intraorbital mass that was increasing in size and associated with paresthesia and a recent history of excision of squamous cell carcinomas (SCC) from his left cheek. Fine needle aspiration biopsy (FNAB) yielded very limited material, predominantly blood. However, 1 Papanicolaou-stained slide showed groups of atypical cells with scanty but dense cytoplasm and large, hyperchromatic nuclei with prominent nucleoli. SCC was favored, and excision was performed. Histology showed PEH within an assumed cystic lymphangioma, associated with inflammatory and fibrotic change in the compressed supraorbital nerve.

CONCLUSION

To our knowledge this is the third report on the cytology of PEH and the first report of FNAB in PEH of the orbit. The case was also unusual as it was the second metachronous PEH in the patient.

Prominent Corneal Nerves in a Patient With Multiple Myeloma

PURPOSE

To describe a case of prominent corneal nerves observed in a patient after diagnosis of multiple myeloma.

METHODS

Case report and literature review.

RESULTS

A 65-year-old woman with a history of multiple myeloma was referred for chronic epitheliopathy in the left eye. She was diagnosed with multiple myeloma 3 years before presentation and underwent treatment at that time. On examination, she was noted to have prominent corneal nerves bilaterally with absent corneal sensation.

CONCLUSION

Multiple myeloma caused prominent corneal nerves and reduced corneal sensitivity.

Corneal Innervation and Cellular Changes after Corneal Transplantation: An In Vivo Confocal Microscopy Study

PURPOSE

Although penetrating keratoplasty is generally considered a successful procedure, transplanted corneal tissue may exhibit abnormal epithelium, decreased sensation, and declining endothelial cell counts after surgery. This study aimed to use in vivo confocal microscopy to correlate corneal microstructure and recovery of the subbasal nerve plexus of the transplanted cornea with indications for, and time from, surgery.

METHODS

This was a cross-sectional study comparing corneas from 42 patients after penetrating keratoplasty with those of 30 controls. Subjects were assessed by ophthalmic history and clinical examination, computerized corneal topography, and laser scanning in vivo confocal microscopy.

RESULTS

Time from surgery ranged from 1 month to 40 years (mean, 85 +/- 105 months). Significant reductions in epithelial (P < 0.001), keratocyte (P < 0.001), and endothelial (P < 0.001) cell densities were noted in comparison with control corneas. Significant reductions in subbasal nerve fiber density (P < 0.001) and nerve branching (P < 0.001) were also noted. Endothelial cell density decreased with time after surgery (r = -0.472; P = 0.003), and nerve fiber density (r = .328; P = 0.034) increased. Keratoconus as an indication for transplantation was associated with higher subbasal nerve fiber densities (P = 0.003) than other indications for corneal transplantation. Neither nerve fiber nor cell density was correlated with best-corrected visual acuity.

CONCLUSIONS

Laser scanning in vivo confocal microscopy highlights profound reductions in cell density at every level of the transplanted cornea and alterations to the subbasal plexus that are still apparent up to 40 years after penetrating keratoplasty.

Endoscopic excision of a supraorbital schwannoma

Patients with neurofibromatosis 1 frequently require multiple tumor excisions over the course of many years. Minimally invasive techniques of excision offer promise in reducing morbidity and scarring in a group of patients with well-circumscribed benign tumors in aesthetically sensitive areas. The safety and efficacy of endoscopic approaches to a variety of conditions affecting the craniofacial frontal region are well established. This report describes the endoscopic excision of a benign supraorbital nerve schwannoma in a 5-year-old girl.

[Distribution and morphological changes of corneal nerves in type 2 diabetic patients detected by confocal microscopy]

OBJECTIVE

To evaluate corneal nerve distribution and morphological changes in subjects with type 2 diabetes.

METHODS

Sixty-five eyes of 59 patients with type 2 diabetes (26 males, 39 females) and 26 eyes (10 males, 16 females) of control subjects were included in the present study. Based on the indirect ophthalmoscopic examination and fluorescein angiography, the diabetic group was divided into three sub-groups according to the stage of retinopathy: without diabetic retinopathy (NDR), non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR). The central cornea was scanned with Confoscan 3.0. The images of subbasal nerve plexus and stromal nerves were analyzed.

RESULTS

Corneal branch nerve fiber density of subbasal nerve plexus decreased in diabetic group as compared with control group, the difference was statistically significant. The decrease of nerve fiber density appeared only in the PDR sub-group, while the decrease was not significant in NDR and NPDR sub-groups. No obviously difference was found among control group, NDR and NPDR sub-groups. The proportion of patients with an abnormal morphologic nerve fibers in mid-stroma in diabetes group was greater than that in the control group and the difference was statistically significant (chi(2) = 46.613, P = 0.000).

CONCLUSIONS

Corneal confocal microscope allows rapid and noninvasive in vivo evaluation of corneal nerves. The subbasal and stromal nerves of subjects with type 2 diabetes were abnormal in morphology.

Decreased density of corneal basal epithelium and subbasal corneal nerve bundle changes in patients with diabetic retinopathy

PURPOSE

To define alterations in the density of corneal basal epithelium in relation to diabetic retinopathic severity and the alteration of corneal innervation using confocal microscopy.

DESIGN

Prospective case-control study.

METHODS

Forty-two type II diabetic patients stratified into nondiabetic (NDR), nonproliferative diabetic (NPDR), and proliferative diabetic (PDR) retinopathy and 14 age-matched healthy control subjects were studied. Epithelial and stromal cell densities and subbasal nerves were investigated by confocal microscopy.

RESULTS

Corneal basal epithelial cell density (P = .0001), nerve fiber density (NFD) (P < .0001), nerve branch density (NBD) (P = .0003), and tortuosity coefficient (Tc) (P < .0001) were significantly different among the four groups. Basal epithelial density was significantly correlated with NFD (r = 0.43, P = .0009), NBD (r = 0.36, P = .007), and TC (r = -0.58, P < .0001).

CONCLUSIONS

Patients with diabetes show alterations in corneal innervations and basal epithelial cell density in different retinopathic stages. We demonstrate that reduced density in basal epithelial cell is correlated with changes in innervation.

In vivo confocal laser scanning microscopy of the cornea in dry eye

BACKGROUND

We carried out an investigation into the morphological and quantitative corneal properties in dry eye with various underlying pathologies.

METHODS

Ten patients with aqueous tear deficiency, 8 with dysthyroid ophthalmopathy, 8 with chronic lagophthalmos and 10 normal participants were examined. Confocal microscope images were taken at the centre and at the lower and upper periphery of the cornea. Quantitative and morphological assessments of the epithelium, of the sub-basal nerves, of the stroma and the endothelium were made. The epithelial and corneal thicknesses were measured.

RESULTS

The mean superficial and intermediate epithelial cell densities in the central cornea in the patient groups were significantly lower than in normal participants (p<0.01). The peripheral epithelial thickness was smaller (p<0.01); it was smallest in the lagophthalmos group. The cornea was thinner in the patient groups (p<0.01). For sub-basal nerves, the density had decreased (p<0.05), and in lagophthalmos the number of beadlike formations had increased (p<0.001); in some patients we found irregular branching patterns.

CONCLUSIONS

Dry eye patients showed significant alterations in the cornea, presumably due to increased desquamation of the superficial cell layer. This was most pronounced at the lower periphery of the cornea in patients with exposure keratopathy.

Use of nerve growth factor to treat congenital neurotrophic corneal ulceration

PURPOSE

This study was designed to assess the efficacy of nerve growth factor in the treatment of neurotrophic corneal ulceration in a child with bilateral congenital corneal anesthesia secondary to trigeminal insufficiency.

METHODS

A 5-month-old child presented to the casualty department with a 2-week history of red eyes and right corneal ulceration. Slit-lamp examination showed a central defect in the right corneal epithelium with underlying stromal opacification, only mild conjunctival inflammation with slight decreased tear production, and otherwise apparently normal eyes. Initially this was investigated as an infected ulcer and treated for several weeks as herpetic ulceration with no beneficial effect. Further clinical examination demonstrated bilateral decreased corneal sensation along with decreased facial sensation in keeping with congenital trigeminal nerve insufficiency. Investigation with magnetic resonance imaging showed no obvious abnormality. Conservative treatment with lubricants resulted in progressive right corneal stromal loss, and no healing occurred in the left corneal ulcer. Bilateral large lateral tarsorrhaphies were performed. Despite this, the left corneal ulcer demonstrated no improvement and increasing stromal opacification was noted. Topical nerve growth factor (NGF) was then used to treat the left cornea and resulted in epithelial healing within 1 week. Treatment was continued for a further 10 days after epithelial healing. Despite conventional treatment on 3 separate occasions, further epithelial breakdown occurred. Topical NGF treatment resulted in a rapid improvement and healing of the epithelial defect.'At present, the patient is receiving a 6-month continuous treatment plan of NGF.

RESULTS

Persistent epithelial defects (PED) secondary to neurotrophic ulceration have responded to topical NGF on 3 separate occasions during a 2-year period. The corneal epithelium now remains intact, and the cornea has no vascularization; however, mild anterior stromal opacification has gradually increased despite prolonged NGF treatment.

CONCLUSION

NGF seems to represent a safe and efficacious treatment option to restore the integrity of corneal epithelium in which there is congenital corneal anesthesia because of trigeminal insufficiency. However, this treatment alone is insufficient to prevent progressive anterior stromal opacification.

Mapping the Corneal Sub-basal Nerve Plexus in Keratoconus by In Vivo Laser Scanning Confocal Microscopy

PURPOSE

To produce a two-dimensional reconstruction map of the living corneal sub-basal nerve plexus in keratoconus with in vivo confocal microscopy.

METHODS

Four eyes of four subjects with keratoconus were examined by slit lamp biomicroscopy, Orbscan II slit-scanning elevation topography (Bausch & Lomb Surgical, Rochester, NY), and laser scanning in vivo confocal microscopy with the Heidelberg Retina Tomograph II, Rostock Corneal Module (Heidelberg Engineering, Heidelberg, Germany). Subjects were asked to fixate on targets arranged in a grid to enable in vivo confocal microscopy of the cornea in a wide range of positions.

RESULTS

A mean of 402 +/- 57 images were obtained for each cornea, to create confluent montages. The mean dimensions of the corneal areas mapped were 6.60 +/- 0.70 mm horizontally and 5.91 +/- 0.72 mm vertically. All corneas exhibited abnormal sub-basal nerve architecture compared with patterns previously observed in normal corneas. At the apex of the cone, a tortuous network of nerve fiber bundles was noted, many of which formed closed loops. At the topographic base of the cone, nerve fiber bundles appeared to follow the contour of the base, with many of the bundles running concentrically in this region. Central sub-basal nerve density was significantly lower in keratoconus corneas (10,478 +/- 2,188 microm/mm2) compared with normal corneas (21,668 +/- 1,411 microm/mm2; Mann-Whitney; P < 0.01).

CONCLUSIONS

This is the first study to elucidate the overall distribution of sub-basal nerves in the living central to midperipheral human cornea in keratoconus, using laser scanning in vivo confocal microscopy.

Herpes zoster ophthalmicus: presenting as giant-cell arteritis

A 74-year-old woman was referred to the authors' clinic with a 1-week suspicion of giant-cell arteritis. Uncomplicated, bilateral temporal artery biopsies were performed 3 days after admission for therapy. Four hours after the procedure she developed vesicular lesions of the face compatible with herpes zoster ophthalmicus. The temporal artery biopsy revealed perineural lymphocytic aggregation. Both giant-cell arteritis and herpes zoster ophthalmicus form part of the differential diagnosis in elderly patients with headache. In such cases, clues from a temporal artery biopsy may aid in diagnosis of herpes zoster. In addition, the patient in this case developed the rash 10 days after onset of symptoms, which is rare as the average time from onset of symptoms to rash in zoster is 3-5 days.

Diagnostic accuracy of trigeminal reflex testing in trigeminal neuralgia

The authors prospectively studied 120 consecutive patients with trigeminal neuralgia (TN) to identify the clinical and laboratory features that most accurately distinguished symptomatic from classic TN. After a standardized evaluation, they identified 24 patients with symptomatic TN. Age, sensory examination, and affected division were not useful in the differential diagnosis. In contrast, electrophysiologic testing of trigeminal reflexes accurately distinguished symptomatic from classic TN (sensitivity 96%, specificity 93%).

Unilateral hypoplasia of the trigeminal ganglion

CASE REPORT

We report a case of unilateral anaesthesia of the V1 (ophthalmic) division of the trigeminal cranial nerve presenting with persistent corneal erosions and ulceration secondary to trigeminal ganglion hypoplasia. The patient had a lifelong history of unexplained left-sided ophthalmic symptoms for which numerous diagnoses were provided. Cranial nerve testing demonstrated partial trigeminal dysfunction on the left side. Further investigation eliminated viral etiologies, and subsequent magnetic resonance imaging determined that the patient had a hypo-plastic left trigeminal ganglion.

COMMENTS

We present the case to alert clinicians to the possibility of this rare condition.

An evaluation of corneal nerve morphology and function in moderate keratoconus

PURPOSE

To investigate corneal nerve morphology and corneal sensitivity in keratoconus.

METHODS

The central cornea of 13 subjects with keratoconus and 13 age-matched control subjects was assessed using in vivo confocal microscopy and corneal aesthesiometry.

RESULTS

Significant differences in corneal nerve fibre density were found between the subjects with keratoconus and the control subjects (keratoconus versus control; 1018.3+/-489.6 microm versus 1820.7+/-789.5 microm; p = 0.006). The mean diameter of nerve fibres in the stroma was found to be greater in subjects with keratoconus compared to control subjects (keratoconus versus control; 10.2+/-4.6 microm versus 5.5+/-1.9 microm; p = 0.007). The orientation of corneal nerve fibres in the subjects with keratoconus appeared to be altered from the predominantly vertical orientation seen in the control subjects. Corneal touch threshold was found to be similar in the two groups, although the subjects with keratoconus using contact lens correction had reduced corneal sensitivity compared to the contact lens-wearing control subjects (keratoconus with contact lenses versus controls with contact lenses; 1.18+/-0.19 g/mm2 versus 0.98+/-0.05 g/mm2; p = 0.03).

CONCLUSION

This study reveals significant reductions in nerve density in the keratoconic cornea. The thickened stromal nerve fibres observed in the keratoconic corneas may explain why prominent corneal nerves are often seen using slit lamp biomicroscopy in keratoconic patients.

Altered Corneal Nerves in Aqueous Tear Deficiency Viewed by In Vivo Confocal Microscopy

PURPOSE

To define the alterations of corneal nerves in aqueous tear deficiency dry eye patients with or without Sjögren syndrome and to identify the relationship between the morphologic changes of corneal nerves and the extent of dry eye.

METHODS

Confocal microscopy was used to examine 38 consecutive aqueous tear deficiency patients (8 Sjögren syndrome and 30 non-Sjögren syndrome) and 30 age- and gender-matched normal controls. Images taken by Confocal2 slit-scanning microscope at subbasal epithelial cell layer of central cornea were analyzed. The number and density of corneal nerves and their size, beads, tortuosity, and branching pattern were compared. These data were correlated with age and the degree of dry eye.

RESULTS

Sjögren syndrome patients showed a significant increase in average nerve number and tortuosity as compared with normal controls (P = 0.031 and 0.021, respectively). Severe nerve tortuosity (grade 4) and nerve branching appeared more frequently in aqueous tear deficiency than in normal subjects (P = 0.024 and 0.042, respectively). A decreased nerve number was observed with age in the normal controls (P = 0.002). However, such a correlation did not exist in aqueous tear deficiency. In aqueous tear deficiency, rose bengal staining score correlated positively with nerve density (P = 0.048) and nerve number (P = 0.001). Corneal fluorescein staining score was also positively correlated with nerve number (P = 0.027).

CONCLUSIONS

Abnormal morphologic changes are observed in aqueous tear deficiency that are more severe in Sjögren syndrome. The distinct changes of corneal nerves include increased nerve number, tortuosity, and chances of branching, suggesting an attempted nerve regeneration. A strong correlation exists between the changes of nerve morphology and the degree of dry eye. These results provide some possible evidence for the abnormal corneal sensation in dry eye.

Ocular Surface Changes in Laser in situ Keratomileusis-induced Neurotrophic Epitheliopathy

PURPOSE

To evaluate the ocular surface changes in patients with laser in situ keratomileusis (LASIK)-induced neurotrophic epitheliopathy.

METHODS

Seven consecutive patients with LASIK-induced neurotrophic epitheliopathy were studied prospectively and compared to a control group (seven consecutive patients who had LASIK- but without neurotrophic epitheliopathy). Bilateral sequential LASIK was performed at a 1-week interval; the first operated eye of each patient was considered for statistical analysis. Blinking, corneal sensitivity, tear break-up time, tear secretion and clearance were measured preoperatively (T0) and postoperatively at 1 week after surgery on the first eye (T1), and 1 week (T2), 1 month (T3), and 3 months (T4) after surgery was performed on the second eye.

RESULTS

Laser in situ keratomileusis-induced neurotrophic epitheliopathy occurred bilaterally in all patients. During follow-up, patients with LASIK-induced neurotrophic epitheliopathy showed a significant decrease in blinking (P = .0002), which was not observed in cases without LASIK-induced neurotrophic epitheliopathy [corrected] Compared to eyes without LASIK-induced neurotrophic epitheliopathy, those with LASIK-induced neurotrophic epitheliopathy revealed lower values of sensitivity in the central cornea preoperatively and early postoperatively (T0, P = .004; T1, P = .003; T2, P = .003). A trend towards reduced sensitivity was also detected in the central cornea in late follow-up and in the superior, temporal, and nasal sectors of the flap at all examinations. No significant differences were observed in break-up time, tear secretion, or clearance within or between the two groups.

CONCLUSION

Decreased blinking seems to be involved in the pathogenesis of LASIK-induced neurotrophic epitheliopathy. The reduction probably depends on the lower levels of corneal sensitivity and induces the epitheliopathy by increasing the ocular surface exposure.

[Analysis of clinical manifestations in nasociliary neuralgia]

OBJECTIVE

To explore the clinical character of nasociliary neuralgia and improve the level of diagnosis and treatment.

METHOD

Forty-three cases with nasociliary neuralgia were diagnosed and treated in our hospital. The clinical data were analyzed retrospectively.

RESULT

It was easy to be misdiagnosed for nasociliary neuralgia,the rate of misdiagnosis was 69.8% (30/43). Performing the resection of upper nasal septum deviation, partial middle turbinetectkomy or/and folded, 43 cases were followed up from 6 to 24 months,the cural rate and the improve rate were 95.3% and 4.7% respectively, with the total effective rate 100.0%.

CONCLUSION

Most patients with nasociliary neuralgia are middle-aged women. It is similar to ethmoid sinusitis and frontal sinusitis in headache, but no suppurative rhinorrhea. Careful examination of nasal cavity and CT scan in sinus play an important role in avoiding misdiagnosis. The corrective surgery of middle turbinate and nasal septum are effective treatment and the complication of dysosmia can be avoided.

Isolated, benign, intraorbital schwannoma arising from the supraorbital nerve. Case report and review of the literature

The authors describe the rare case of a 65-year-old man, with absent clinical evidence of von Recklinghausen's disease, harbouring an isolated, benign schwannoma of the right supraorbital nerve. The patient presented a progressive, painless proptosis of the eye for the past 2 years, did not complain of any intra- or periorbital pain, and did not experience any form of visual disturbance or field defect. The lesion was completely resected using a fronto-orbitozygomatic approach. The clinicopathological, radiological and surgical features are discussed, and the literature on supraorbital nerve schwannomas reviewed. To the authors' knowledge the fronto-orbitozygomatic approach has not been previously reported for the removal of supraorbital nerve tumors.

Corneal nerve tortuosity in diabetic patients with neuropathy

PURPOSE

Corneal confocal microscopy is a reiterative, rapid, noninvasive in vivo clinical examination technique capable of imaging corneal nerve fibers. Nerve fiber tortuosity may indicate a degenerative and attempted regenerative response of nerve fibers to diabetes. The purpose of this study was to define alterations in the tortuosity of corneal nerve fibers in relation to age, duration of diabetes, glycemic control, and neuropathic severity.

METHODS

The cornea and collected images of the subbasal nerve plexus of 18 diabetic patients (stratified into mild, moderate, and severe neuropathic groups using conventional clinical measures of neuropathy) and 18 age-matched nondiabetic control subjects were scanned, and a novel mathematical paradigm was applied to quantify the extent of nerve tortuosity, which was termed the tortuosity coefficient (TC).

RESULTS

TC was significantly different between the four clinical groups (F(3) = 12.2, P < 0.001). It was significantly greater in the severe neuropathic group than in control subjects (P < 0.003) and in the mild (P < 0.004) and moderate (P < 0.01) neuropathic groups. TC did not correlate significantly with the age (r = -0.003, P > 0.05), duration of diabetes (r = -0.219, P > 0.05), or hemoglobin A1c (HbA1c; r = 0.155, P > 0.05) of diabetic patients.

CONCLUSIONS

Corneal confocal microscopy allows rapid, noninvasive in vivo evaluation of corneal nerve tortuosity. This morphologic abnormality relates to the severity of somatic neuropathy and may reflect an alteration in the degree of degeneration and regeneration in diabetes.

Corneal innervation and morphology in primary Sjögren's syndrome

PURPOSE

To analyze the in vivo morphology of the different corneal sublayers and corneal nerves in primary Sjögren's syndrome (SS).

METHODS

Ten eyes of 10 patients with primary SS and 10 eyes of 10 sex- and age-matched control subjects were investigated. Diagnosis was based on American-European consensus criteria. In vivo confocal microscopy with through-focusing was used to investigate corneal morphology and to measure corneal sublayer thickness.

RESULTS

Epithelial punctate staining with fluorescein was observed in 6 of 10 SS and none of 10 control corneas. In addition, Schirmer I test results were significantly lower in SS. Epithelial thickness did not differ between the SS and control groups. Confocal microscopy revealed patchy alterations or irregularities in surface epithelial cells in 6 of 10 SS corneas, whereas the basal epithelium appeared normal in all corneas. Average corneal thickness was lower in the SS group (515.9 +/- 22.0 micro m) than in the control (547.4 +/- 42.0 micro m; P = 0.050, t-test). Accordingly, the mean intraocular pressure was lower in the SS group (13.9 +/- 2.1 mm Hg) than in the control (16.7 +/- 2.9 mm Hg; P = 0.022). The subbasal nerve plexus and stromal nerve fiber bundles were present in all corneas. No difference was noted in nerve density. However, in 4 of 10 SS eyes, the subbasal nerve plexus showed structures resembling nerve sprouting, suggesting ongoing active neural growth. None of the control corneas exhibited such features. Signs of anterior keratocyte activation were observed in 5 of 10 SS corneas.

CONCLUSIONS

In SS, the corneal surface epithelium was irregular and patchy. Anterior keratocytes frequently showed morphologic features of activation. The subbasal nerve fiber bundles revealed abnormal morphology, and the central corneal thickness was reduced by stromal thinning. The findings confirm epithelial, stromal, and neural abnormalities in the corneas of patients with SS.

In vivo confocal microstructural analysis and surgical management of Brown-Mclean syndrome associated with spontaneous crystalline lens luxation

We report 3 members of an extended family who presented with bilateral peripheral corneal edema consistent with Brown-McLean syndrome. On clinical examination, all eyes demonstrated normal central corneas and marked peripheral edema. In vivo confocal microscopy of the peripheral cornea highlighted similar observations in the 6 eyes including endothelial pigmentation, masked stromal structure due to edema, prominent nerves, and localized basal epithelial edema. In the central cornea, in vivo confocal microscopic observations highlighted large cellular structures with prominent nuclei in groups consisting of several cells of similar appearance. In vivo confocal microscopy may enhance the diagnosis of Brown-McLean syndrome and may be used for dynamic evaluation and postoperative follow-up of the structural corneal changes.

[Bilateral neurotrophic keratitis secondary to encephalic trunk metastasis]

CASE REPORT

We report the case of a 69-year-old man with a lung carcinoma history. The patient showed signs of conjuntival hyperemia, painless bilateral corneal edema, persistent epitelial defects and reported to have decreasing visual acuity for a week. The clinical examination revealed a bilateral neurotrophyc keratitis with both a decreased frequency of blinking and a bilateral atrophy mandibular muscles. Local ocular patology was excluded. Systemic exploration showed a meningeal neoplasic infiltration and metastasis on the initial trigeminal nerve stretch. In our knowledge, this is the first case reported in the literature.

DISCUSSION

Ophthalmic signs should be considered in the diagnosis of systemic pathology.

An unusual case of stabbing eye pain: a case report and review of trigeminal neuralgia

BACKGROUND

Trigeminal neuralgia is a painful neurological disorder that affects one or more of the divisions of the trigeminal nerve. It is characterized by brief attacks of stabbing pain that can be excruciating. These attacks may be triggered by a light touch, shaving, or even eating. There has been much debate over the exact etiology of trigeminal neuralgia. One of the main theories is vascular compression of the trigeminal nerve as it leaves the brainstem. Another theory suggests that intracranial tumors--particularly those located in the posterior fossa--may be the cause. Trigeminal neuralgia is also associated with multiple sclerosis.

CASE REPORT AND REVIEW

A 79-year-old man came to the eye clinic with signs and symptoms consistent with trigeminal neuralgia involving the ophthalmic and maxillary divisions of the nerve. A neurological evaluation confirmed the diagnosis, and proper medical treatment was subsequently implemented to relieve his pain.

CONCLUSION

Patients who manifest symptoms consistent with trigeminal neuralgia should be referred for a neurological evaluation, including MRI. With the proper medical and/or surgical treatment, the quality of life of these patients can increase dramatically.

Effects of cyclophotocoagulation with a neodymium:yttrium-aluminum-garnet laser on corneal sensitivity, intraocular pressure, aqueous tear production, and corneal nerve morphology in eyes of dogs

OBJECTIVE

To determine effects of cyclophotocoagulation via administration of 100 J with a neodymium:yttrium aluminum garnet (Nd:YAG) laser on corneal touch threshold (CTT), intraocular pressure (IOP), aqueous tear production, and corneal nerve morphology in eyes of dogs.

ANIMALS

15 dogs.

PROCEDURE

Noncontact Nd:YAG laser was transsclerally applied (10 applications; 25 W for 0.1 seconds for each application to each of 4 quadrants) to the ciliary body of the left eye of 15 dogs; the right eye was the control eye. Corneal integrity, CTT, tear production as measured by the Schirmer tear test (STT), and IOP were evaluated for 14 days following laser treatment. On day 14, dogs were euthanatized, eyes harvested, and corneas stained with gold chloride. Major nerve bundles were analyzed by use of a drawing tube attached to a light microscope, and maximum diameters were measured by use of image analysis software.

RESULTS

All laser-treated eyes had significantly higher CTT values, compared with control eyes. Six of 15 laser-treated eyes developed ulcerative keratitis. On most days, IOP was significantly lower in laser-treated eyes in both morning and evening. Laser-treated eyes had a significant decrease of approximately 1 nerve bundle/corneal quadrant. Values for STT or nerve bundle diameters did not differ significantly.

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of 100 J with a Nd:YAG laser effectively reduced IOP while increasing CTT and caused a significant decrease in number, but not diameter, of major corneal nerve bundles. Nerve damage and corneal hypoesthesia are etiologic factors in ulcerative keratitis following Nd:YAG cyclophotocoagulation.

Confocal microscopy in Meretoja syndrome

PURPOSE

To study the correlation between severity of clinical systemic symptoms and the degree of stromal haze and visibility of epithelial and stromal nerves on scanning slit confocal microscopy examination in Meretoja syndrome.

METHODS

Three patients with Meretoja syndrome were examined by slit-lamp microscopy and scanning slit confocal microscopy.

RESULTS

Increased symptoms and abnormal slit-lamp findings correlated positively with confocal microscopic stromal haze intensity and inversely with visibility of epithelial and stromal nerves on confocal examination. A prominent deposit, presumably amyloid, was observed contiguous to a stromal nerve of an affected cornea. In a severely affected cornea, no stromal or epithelial nerves were seen.

CONCLUSION

The results of this study suggest that Meretoja syndrome causes corneal nerve damage and eventual degeneration that correlates with the degree of clinical involvement.

In vivo confocal microscopy after herpes keratitis

PURPOSE

To describe the confocal microscopic findings, with special reference to corneal subbasal nerves, after herpes simplex virus (HSV) keratitis.

METHODS

In this study, 16 HSV eyes and 14 contralateral eyes of 16 patients, diagnosed with unilateral HSV keratitis 1-12 months earlier by the presence of dendritic corneal ulceration or microbiologic confirmation, were examined by in vivo confocal microscopy for evaluation of corneal morphology.

RESULTS

Herpes simplex virus eyes: In 2 eyes the surface epithelial cells appeared large, and no abnormalities were observed in the basal epithelial cells. In 2 eyes subbasal nerve fiber bundles were completely absent, in 3 eyes there was a reduced number of long nerve fiber bundles, and in 11 eyes the subbasal nerve plexus appeared normal. In 10 corneas, highly reflective dendritic structures were found at the level of the basal epithelial cells. Frequently these structures were found in the vicinity of stromal fibrosis. Areas with increased abnormal extracellular matrix were found in 11 eyes. Stromal nerves were not visualized in all corneas, but appeared normal when observed. Contralateral eyes: No abnormalities were observed in the epithelium. All corneas presented with a normal subbasal nerve plexus, but in 2 eyes dendritic particles were observed. Three corneas presented with activated keratocytes and increased amounts of abnormal extracellular matrix.

CONCLUSIONS

When visualized by confocal microscopy, the subbasal nerve plexus appears relatively unaffected in cases with resolved HSV keratitis. Unidentified dendritic structures, presumably Langerhans cells, are frequently seen at the level of the basal epithelium in corneas with a history of herpetic disease.

Laser in situ keratomileusis-induced neurotrophic epitheliopathy

PURPOSE

To report two cases of laser in situ keratomileusis-induced neurotrophic epitheliopathy with punctate epitheliopathy and rose bengal staining of the corneal flap.

METHODS

Interventional case reports.

RESULTS

A 42-year-old woman and a 37-year-old man with no preoperative symptoms or signs of dry eye developed dry eye symptoms and bilateral punctate epithelial erosions as well as rose bengal staining of the corneal flaps after laser in situ keratomileusis. Neither patient had less than 12 mm of wetting with the Schirmer test without anesthesia at any time point between development and resolution of the flap surface abnormalities. The flap surface abnormalities resolved approximately 6 months after laser in situ keratomileusis.

CONCLUSIONS

Laser in situ keratomileusis-induced neurotrophic epitheliopathy may be attributable to loss of trophic influence from severed corneal nerve trunks. The condition typically resolves approximately 6 months after laser in situ keratomileusis or laser in situ keratomileusis retreatment.

Typical ocular findings in a patient with multiple endocrine neoplasia type 2b syndrome

BACKGROUND

Multiple endocrine neoplasia (MEN) type 2b syndrome is accompanied by typical ocular findings; however, the disease is often only diagnosed at an advanced stage by symptoms of C-cell carcinoma or pheochromocytoma and is then fatal in most cases. Therefore, the importance of ophthalmic assessment in making the diagnosis has to be stressed.

METHODS

The history and ocular findings of a patient with MEN 2b syndrome are described, and a brief overview of the syndrome is given.

RESULTS

Slit-lamp examination showed extremely thickened corneal nerves as well as multiple small plexiform and nodular subconjunctival tumors. Both eyes also displayed thickened upper and lower eyelids. A molecular genetic study of the RET proto-oncogene showed a heterozygous ATG to ACG mutation in codon 918 of exon 16.

CONCLUSION

Greatly thickened corneal nerves and subconjunctival tumors may be the first hint of MEN 2b. Whenever greatly thickened corneal nerves are detected, MEN 2b must be ruled out.

Laser in situ keratomileusis-induced (presumed) neurotrophic epitheliopathy

OBJECTIVE

To evaluate tear production, corneal topography, accuracy of refractive correction, and best spectacle-corrected visual acuity in eyes that had moderate to severe rose bengal staining develop on the flap compared with eyes with little or no staining on the flap, the first few months after laser in situ keratomileusis (LASIK). None of the eyes in this study had significant preoperative dry eye disease.

DESIGN

Retrospective case control study.

PARTICIPANTS

Individual eyes of 19 consecutive patients with moderate to severe punctate epithelial erosions and rose bengal staining on the flap 1 to 3 months after LASIK were compared with eyes of 19 concurrent patients who did not have punctate epithelial erosions or more than trace staining on the flap develop.

METHODS

Nonparametric statistical analyses were used to compare tear secretion, corneal topographic irregularity, spherical equivalent, and visual acuity 3 and 6 months after surgery. Some eyes in both groups also had analysis of tear secretion 1 month after surgery.

MAIN OUTCOME MEASURES

Schirmer's test without anesthesia, the topographic corneal irregularity measurement (CIM), the difference between attempted and achieved spherical equivalent, and the loss of best spectacle-corrected visual acuity.

RESULTS

There was no difference in tear production 1, 3, or 6 months after LASIK in patients who had punctate epithelial erosions and rose bengal staining on the flap develop and those who did not. There was no significant difference in the CIM or mean accuracy of the refractive correction in the two groups, but some patients had a transient decrease in best spectacle-corrected visual acuity. Flap rose bengal staining resolved by 6 months after LASIK in most affected patients.

CONCLUSIONS

LASIK-induced rose bengal staining in patients without preexisting dry eye is likely neurotrophic epitheliopathy, because there is no difference in mean tear production between patients who have significant punctate epithelial erosions and rose bengal staining develop on the flap and those who do not. The signs and symptoms of LASIK-induced (presumed) neurotrophic epitheliopathy tend to resolve approximately 6 months after surgery. This disorder tends to be more common and severe in patients with pre-existing dry eye disease.

Corneal morphology and sensitivity in lattice dystrophy type II (familial amyloidosis, Finnish type)

PURPOSE

To describe the corneal abnormalities and to measure different modalities of corneal sensitivity in corneal lattice dystrophy type II (familial amyloidosis, Finnish type, also known as gelsolin-related amyloidosis and originally as Meretoja syndrome).

METHODS

Twenty eyes of 20 patients were examined by in vivo confocal microscopy and noncontact gas esthesiometry.

RESULTS

Pleomorphism of, and dense deposits between or posterior to, the basal epithelial cells were frequently observed, as well as a reduction of long nerve fiber bundles in the subbasal nerve plexus. The anterior stroma was altered in most cases, with fibrosis and abnormal extracellular matrix. In 15 corneas, thick anterior and midstromal filaments, corresponding to lattice lines, and in 11 corneas, thin undulated structures were observed. The average mechanical sensitivity threshold of 12 subjects was increased, and in the remaining 8 subjects there was no response, even to the highest intensity of stimuli used. Three patients did not respond to CO(2), 11 to heat, and 2 to cold, but those patients who responded had normal thresholds. Patients with more long nerve fiber bundles per confocal microscopic image had better mechanical and cold sensitivity than patients with fewer nerve fiber bundles.

CONCLUSIONS

Lattice lines seem to be related to amyloid material and not to corneal nerves. However, the subbasal nerve density appears reduced, which results mainly in a decrease in mechanical and, to a lesser extent, thermal sensitivity. The location of stromal filaments and undulated structures changes with increasing age.

Corneal structure and sensitivity in type 1 diabetes mellitus

PURPOSE

Corneal wound healing is impaired in diabetic cornea. The purpose of this study was to examine patients with type 1 diabetes mellitus for changes in corneal morphology and to correlate corneal sensitivity, subbasal nerve morphology, and degree of polyneuropathy with each other.

METHODS

Forty-four eyes of 23 patients with diabetes and nine control eyes were included. Corneal sensitivity was tested with a Cochet-Bonnet esthesiometer (Luneau, Paris, France), and corneal morphology and epithelial and corneal thickness were determined by in vivo confocal microscopy. The density of subbasal nerves was evaluated by calculating the number of long subbasal nerve fiber bundles per confocal microscopic field. The degree of polyneuropathy was evaluated using the clinical part of the Michigan Neuropathy Screening Instrument (MNSI) classification, and retinopathy was evaluated using fundus photographs.

RESULTS

A reduction of long nerve fiber bundles per image was noted to have occurred already in patients with mild to moderate neuropathy, but corneal mechanical sensitivity was reduced only in patients with severe neuropathy. Compared with control subjects the corneal thickness was increased in patients with diabetes without neuropathy. The epithelium of patients with diabetes with severe neuropathy was significantly thinner than that of patients with diabetes without neuropathy.

CONCLUSIONS

Confocal microscopy appears to allow early detection of beginning neuropathy, because decreases in nerve fiber bundle counts precede impairment of corneal sensitivity. Apparently, the cornea becomes thicker in a relatively early stage of diabetes but does not further change with the degree of neuropathy. A reduction in neurotrophic stimuli in severe neuropathy may induce a thin epithelium that may lead to recurrent erosions.

Topical treatment with nerve growth factor for neurotrophic keratitis

OBJECTIVE

To evaluate the efficacy of nerve growth factor (NGF) in patients with neurotrophic keratitis.

DESIGN

Prospective, noncomparative, interventional case series.

PARTICIPANTS

Forty-five eyes of 43 consecutive patients with moderate (stage 2, n = 17) to severe (stage 3, n = 28) neurotrophic keratitis unresponsive to other nonsurgical therapies.

METHODS

After a 10-day washout with preservative-free artificial tears, 45 eyes with neurotrophic keratitis received murine NGF (200 microg/ml) every 2 hours for 2 days followed by one drop six times daily until the ulcer healed. A maintenance dose of one drop NGF (100 microg/ml) was administered four times daily for the 2 weeks subsequent to ulcer healing.

MAIN OUTCOME MEASURES

Size and depth of the ulcer or the epithelial defect, corneal sensitivity, best corrected visual acuity, side effects, and relapse of the disease in the follow-up period.

RESULTS

All patients had a complete resolution of the persistent epithelial defect (with or without an ulcer) after 12 days to 6 weeks of treatment with NGF. Patients affected by both stages of the disease demonstrated both improved corneal sensitivity and visual acuity (P<0.001). No significant differences were observed in the time to complete corneal healing between stage 2 and stage 3 patients. Hyperemia and ocular and periocular pain were side effects reported during the first days of treatment. No relapse of the disease was observed during the follow-up period, with the exception of three patients with trigeminal nerve resection, who required a single retreatment.

CONCLUSIONS

Nerve growth factor eye drops improved corneal sensitivity and promoted corneal epithelial healing in both moderate and severe neurotrophic keratitis. Although performed in an uncontrolled and nonrandomized series of patients, this therapy shows promise for the restoration of ocular surface integrity and visual function in neurotrophic corneal disease.