Analysis and comparison of proteomic profiles of tear fluid from human, cow, sheep, and camel eyes.

PURPOSE: To investigate the tear proteome profiles of human, cow, sheep, and camel comparatively and to explore the difference of tear protein profiles among different species. METHODS: Tears were collected from both eyes of 25 clinically healthy volunteers, 50 cows, 25 sheep, and 50 camels. Pooled tear protein samples were separated by SDS-PAGE and two-dimensional electrophoresis. Protein spots of differential expression were excised and subjected to in-gel digestion and identification by matrix assisted laser desorption/ionization-time-of-flight/time-of-flight mass spectrum analysis. Because of the incomplete genomic data of cow, sheep, and camel, a combined strategy of de novo sequencing and BLAST (Best Local Alignment Search Tool) homology searching was also used for protein identification. The differentially expressed proteins were validated by Western blot analysis. RESULTS: On comparison with human tears (182 ± 6 spots), 223 ± 8, 217 ± 11, and 241 ± 3 well-resolved protein spots were detected in triphenylmethane dye-stained gels of cow, sheep, and camel tears, respectively. Similar high-abundant proteins (lactoferrin, lysozyme, etc.) were found in all tear fluids. Tear lipocalins have been identified in cow and sheep tears. BLAST searching revealed a 21-kDa protein, identical with human vitelline membrane outer layer protein 1 (VMO1) homolog, in camel tears. The Western blot confirmed that VMO1 homolog was present in both camel and sheep tears but not in human and cow tears. CONCLUSIONS: The comparative proteomic analyses of tears from healthy humans, cows, sheep, and camels were first reported. Differential protein expression existed in the tear among species, offering useful information for further study on tear proteins and the related ocular diseases.

Comparison of camel tear proteins between summer and winter.

PURPOSE: Proteins in the tear fluid have positive effects on maintaining the integrity and stabilization of the tear film, which is affected by several environmental factors. The aim of this study is to investigate seasonal variation of protein patterns in camel tears collected during the summer and winter season. METHODS: Tears from both eyes of 50 clinically normal camels (Camelus dromedarius) were collected in the summer (June-July) and in the winter (December-January) respectively. Pooled tear protein samples from two seasons were separated by SDS-PAGE and two-dimensional electrophoresis (2-DE). Protein spots of differential expression in two season gels were excised and subjected to in-gel digestion and identification by matrix assisted laser desorption/ionization-time of flight/time of flight-mass spectrum (MALDI-TOF/TOF-MS) analysis. Two differentially expressed proteins, lactoferrin (LF) and vitelline membrane outer layer protein 1 homolog (VMO1 homolog), were validated by western blotting. RESULTS: Thirteen well resolved bands were detected in SDS-PAGE gels of both summer and winter camel tears. By band densitometry, significantly higher intensities of band 6, 7, 11, and lower intensity of band 13 were observed in the summer group compared to the winter group. In 2-DE profiles of camel tears, four protein spots were found expressed differentially in two seasons. Further protein identification by MALDI-TOF/TOF-MS and confirmation by western blotting indicated that there was a significant decrease in LF (p=0.002) and an increase in VMO1 homolog (p=0.042) in tears in the summer compared to the winter. CONCLUSIONS: The seasonal variation of camel tear fluids has been found in the composition of proteins, including LF and VMO1 homolog. This result will expand our knowledge of physiologic characteristics of tear fluids and establish a foundation for the mechanistic studies and clinical practices on ocular surface disorders.

Bilateral infectious keratitis after implantation of intrastromal corneal ring segments.

PURPOSE: To report the development of bilateral infectious keratitis after implantation of intrastromal corneal ring segments (ICRSs). DESIGN: Retrospective case report. PARTICIPANTS: A 20-year-old woman presented with photophobia, decreased vision, and pain 11 days after uncomplicated implantation of ICRSs for keratoconus in both eyes. Bilateral corneal stromal infiltrates were noted at the site of ICRSs implantation. INTERVENTION: The patient was started on frequent topical fortified antibiotics in both eyes. Despite aggressive medical management, stromal infiltrates progressed, necessitating removal of ICRSs from both corneas to control infectious keratitis and melting of cornea. METHODS: Retrospective case report of a 20-year-old woman who developed bilateral severe infectious keratitis 11 days after uncomplicated implantation of ICRSs for keratoconus. RESULTS: Cultures obtained at the time of initial presentation yielded Streptococcus viridans. Patient responded well to the treatment and was left with stromal scars in both corneas. CONCLUSIONS: Although rare, simultaneous implantation of ICRSs may carry a risk of severe bilateral infectious keratitis. Early recognition of infection, aggressive treatment with antibiotics, and, in some cases, removal of ICRSs may be necessary to prevent serious sight-threatening complication of this refractive procedure.

Corneoscleral necrosis after episcleral Au-198 brachytherapy of uveal melanoma.

PURPOSE: To describe the risk factors for the development of corneoscleral necrosis (CSN) and its management in patients with primary choroidal or ciliochoroidal melanoma who underwent episcleral Au-198 brachytherapy. METHODS: Clinical records of patients with symptoms of dry eye, foreign body sensation, pain, and evidence of CSN after Au-198 brachytherapy for uveal melanoma treated over a 22-year period were reviewed retrospectively. Risk factors for the development of CSN were identified and various methods of management were evaluated. The data were analyzed using multivariant analysis. A P < 0.05 was taken as a level of statistical significance. RESULTS: Of the 202 eyes of 202 patients treated with Au-198 radioactive plaque, 15 (7.4%) patients with symptomatic complaints of dry eye and pain showed evidence of CSN. First signs were noted as early as 1 month to as late as 5 years (median time 5 months) after the treatment. Risk factors for the development of CSN included tumor thickness greater than 6 mm and ciliary body involvement (P < 0.05). Associated risk factor included intraocular pressure greater than 21 mmHg. Four patients required conservative management, 11 patients required scleral patch and/or conjunctival flaps, and 6 eyes eventually required enucleation. Eyes which developed CSN were more likely to undergo enucleation compared with eyes having no evidence of CSN (P < 0.05). None of the eyes with CSN, which required enucleation because of the failed treatment, had histopathologic evidence of recurrent tumor or tumor invading sclera. CONCLUSION: Corneoscleral necrosis may occur soon or several years after Au-198 brachytherapy for uveal melanoma. Risk factors for CSN include tumor thickness greater than 6 mm, ciliary body involvement, and intraocular pressure >21 mmHg. Closer follow-up, early recognition, and timely intervention may avert serious consequences.

Incidence and visual outcome of endophthalmitis associated with intraocular foreign bodies.

PURPOSE: To determine the risk factors and visual outcome of endophthalmitis associated with traumatic intraocular foreign body (IOFB) removal and its allied management. METHODS: A retrospective review was conducted of patients with penetrating eye trauma and retained IOFB with associated endophthalmitis managed at King Khaled Eye Specialist Hospital over a 22 year period (1983 to 2004). RESULTS: There were 589 eyes of 565 patients (90.3% male; 9.7% female) which sustained ocular trauma and had retained IOFB that required management. Forty-four eyes (7.5%) developed clinical evidence of endophthalmitis at some point after trauma. From these 44 eyes, initial presenting visual acuity (VA) of 20/200 or better was recorded in 8 eyes (18.1%) and the remaining 36 eyes (81.9%) had VA ranging from 20/400 to light perception. Eleven eyes (25%) underwent IOFB removal and repair within 24 hours after trauma while 33 eyes (75%) had similar procedures done 24 hours or more after trauma. Thirty-one eyes (70%) underwent primary pars plana vitrectomy (PPV) at the time of removal of posteriorly located IOFBs. Definite positive cultures were obtained from 17 eyes (38.6%). Over a mean follow-up of 24.8 months, 21 eyes (47.7%) had improved VA, 6 eyes (13.6%) maintained presenting VA while 17 eyes (38.7%) had deterioration of their VA, including 10 eyes (22.7%) that were left with no light perception (NLP) vision. After the treatment of endophthalmitis, 20 eyes (45.4%) had VA of 20/200 or better at their last follow-up. Four eyes (12.9%) from the vitrectomy group (31 eyes) and 5 eyes (45.4%) from non-vitrectomy (11 eyes) group had final VA of NLP. Predictive factors for the good visual outcome included good initial presenting VA, early surgical intervention to remove IOFB (within 24 hours), and PPV. Predictors of poor visual outcome included IOFB removal 48 hours or later, posterior location and no PPV for the posteriorly located IOFB. CONCLUSIONS: Delayed removal of IOFB following trauma may result in a significant increase in the development of clinical endophthalmitis. Other risk factors for poor visual outcome may include poor initial presenting VA, posterior location of IOFB and no vitrectomy at the time of IOFB removal.

Ocular manifestations in Kabuki syndrome: the first report from Saudi Arabia.

BACKGROUND: Kabuki syndrome (KS) is a multiple congenital anomaly syndrome in which ophthalmological examination for the early detection of ocular abnormalities is desired in order to prevent visual impairment. CASE: Retrospective, interventional, case report of a 5-year-old female patient of Arabic origin with features of Kabuki syndrome. OBSERVATION: Patient had neurological deficit, psychomotor retardation, a peculiar face, including large prominent cup shaped ears, broad depressed nasal tip, and high arched palate, and malformed teeth. Her ocular features suggestive of Kabuki syndrome included left upper eyelid congenital ptosis, lagophthalmos, arched eyebrows with temporal sparing of hair, long horizontal palpebral fissures, lateral lower eyelid eversion and resultant epiphora. Other abnormalities included medial lower epicanthal folds, abduction deficit bilaterally, large esotropia, significant hyperopia, right corneal opacity, iris and chorioretinal coloboma. Patient required hyperopic correction and ptosis surgery, which improved her visual functioning. CONCLUSIONS: We report the first case of a Kabuki syndrome patient from Saudi Arabia and stress on the importance of ophthalmological examination in all patients with KS for the early detection of ocular anomalies in order to prevent visual impairment.

Orbital pseudotumor: distinct diagnostic features and management.

PURPOSE: To provide an overview of the spectrum of diseases known as 'idiopathic orbital inflammatory syndrome' also known as orbital pseudotumor, with emphasis on specific diagnostic challenges in the evaluation and management of patients with this disorder. METHODS: Review of the relevant literature and summarize recent findings regarding the epidemiology, diagnosis, pathophysiology and treatment of orbital pseudotumor. RESULTS: Orbital pseudotumor is a benign intraorbital process confined to the orbit but extra orbital involvement can occur. It is among the 3(rd) most common orbital diseases along with thyroid orbitopathy and lymphoproliferative disorder and accounts for 5-10% of orbital processes. Clinically, orbital pseudotumor has been categorized as myositis, dacryoadenitis, anterior, apical and diffuse process. Patients may present with diplopia, conjunctival chemosis, proptosis or abnormal computed tomography scan (CT-scan) findings. Patients may also have associated optic neuropathy. Diagnosis is based on careful history, ultrasonography (U/S), CT-scan and magnetic resonance imaging (MRI) studies which may also provide prognostic information. Treatment consists of systemic corticosteroids in the form of oral or intravenous administration. Confirmation is made by orbital biopsy. In addition to radiation, cytotoxic agents, immunosuppressant, IV immunoglobulin, biological therapy, TNF-alpha inhibitor monoclonal antibody and Mycophenolate Moftil have been found to be useful in the management of refractory orbital pseudotumor. CONCLUSION: Understanding of the clinical features of patients with orbital pseudotumor, differentiating it from other orbital processes by use of imaging techniques and timely implementation of available treatment strategies may help prevent visual loss and associated morbidity from this condition.

Visual recovery after evacuation of orbital emphysema.

Orbital emphysema due to orbital trauma is a well-known occurrence. Visual loss due to orbital emphysema, however, is an uncommon phenomenon. A case of unilateral orbital emphysema following door-handle trauma with subsequent proptosis, painful ophthalmoplegia and compressive optic neuropathy resulting in compromised vision is presented in an 8-year-old male child. Conservative management, including intravenous corticosteroids, failed to resolve the patient's symptoms and compressive optic neuropathy. Surgical intervention to evacuate orbital emphysema resulted in prompt resolution of symptoms, including recovery of vision. A review of the medical literature revealed that only few isolated cases of orbital emphysema with compressive optic neuropathy have been reported previously, with no reports due to door-handle trauma.

L-carnitine protects human retinal pigment epithelial cells from oxidative damage.

PURPOSE: To determine the efficacy of L-carnitine (LC) against oxidative changes in human retinal pigment epithelium (RPE) cells. METHODS: The RPE cells from human donor eyes were cultured in Hams F-10 medium. The effect of LC on H2O2-induced morphologic changes in the RPE cells was analyzed by light microscopy. Reduction in cell death after the impact of LC treatment on H2O2-treated cells was analyzed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays. In addition, the effect of H2O2 on the activity of RPE-antioxidant enzymes, glutathione (GSH) and superoxide dismutase (SOD), and LC-induced protection was also determined. RESULTS: LC protected the RPE cells by inhibiting the peroxide-induced cytopathic effect from 50% to 10%. Nuclear condensation observed in 40% of the H2O2-treated cells decreased to 20% after LC treatment. The MTT assays demonstrated that 100 microM oxidant caused appreciable cell death, which was reduced by LC treatment; however, 100% protection was not achieved. Significant peroxide-induced cell death was seen within 5 hr of H2O2 treatment, and a quantifiable reduction was observed after LC treatment for a similar time period. The change in the antioxidant potential of the RPE induced by oxidative stress was restored by LC treatment, as demonstrated by an increase in GSH and SOD activities. CONCLUSIONS: LC is capable of protecting the RPE cells from H2O2-induced oxidative damage, implying that micronutrients can have a positive effect and can play an important role in the treatment of oxidation-induced ocular disorders. Further studies are needed to understand the mechanism of LC-induced protection to the RPE cells.

Initial diagnosis of leprosy in patients treated by an ophthalmologist and confirmation by conventional analysis and polymerase chain reaction.

PURPOSE: To report the initial diagnosis of leprosy in patients seeking treatment from an ophthalmologist in a tertiary eye care center, its confirmation by histopathologic and polymerase chain reaction analysis, and review of literature. DESIGN: Noncomparative retrospective case series. PARTICIPANTS: Patients with no known history of leprosy who were selected based on either a clinical suspicion or a histopathologic diagnosis and were found to have ocular or periocular lesions suggestive of leprosy. METHODS: Review of clinical records of patients with no known history of leprosy seen by an ophthalmologist at a tertiary eye care referral center. MAIN OUTCOME MEASURES: Patient demographics, presenting symptoms and signs, diagnostic studies, complications, and treatment. RESULTS: Among the 6 patients (5 women and 1 man; average age, 55 years), only 2 were found to have leprosy from clinical examination alone. Histopathologic characteristics or demonstration of acid-fast bacilli, suggestive of leprosy, were found in 5 patients. Definite confirmation of leprosy was made by polymerase chain reaction performed on formalin-fixed, paraffin-embedded tissues of 4 patients having suspected leprosy based on clinicohistopathologic examination results. CONCLUSIONS: The diagnosis of leprosy relies on the clinical symptom complex, epidemiologic factors, and demonstration of acid-fast bacilli in the tissue sample. Considering that the global leprosy population is 12 million, a patient with leprosy may be found anywhere. The ophthalmologist may be the first one to encounter such patient, in which case suspicion and detection of ocular findings may lead to early treatment of the infection. Polymerase chain reaction may be a new tool in the definite diagnosis of leprosy when suspicion of the diseases is raised by clinicohistopathologic studies.

Current indications and resultant complications of evisceration.

PURPOSE: Evisceration is an alternative treatment modality to enucleation for many end-stage eye diseases. No study has addressed the indications for evisceration of eyes in Saudi Arabia. The aim of this study was to determine the current clinical indications for evisceration in patients at a tertiary eye care center and attempt clinicopathological correlation. METHODS: Clinical records of patients who had undergone evisceration at a tertiary eye care center over a 4-year period were reviewed retrospectively. The patients' demographic data and clinical indications for evisceration were studied, and the results from histopathological findings were correlated with the clinical diagnosis. RESULTS: Evisceration of the eyes was performed in 187 patients. Males outnumbered females in a ratio of 1.3:1 (105 males and 82 females). Blind painful eye was the primary presenting symptom in 117 (62.6%) patients and unsightly eye in 38 (20.3%) patients. Clinical indications for evisceration included endophthalmitis in 85 (45.5%), phthisis bulbi in 38 (20.3%), traumatic injury in 36 (19.2%), and glaucoma in 14 (7.5%) patients. Sixty-three patients (33.7%) had prior history of cataract surgery, penetrating keratoplasty, glaucoma surgery, or retina surgery. Clinicopathological correlation was 100% in cases with definite clinical diagnosis of endophthalmitis. CONCLUSION: Blind painful eye, endophthalmitis, phthisis bulbi, severe traumatic injury, and glaucoma were the major indications for eviscerations in a tertiary eye care center.

Congenital cystic eye with intracranial anomalies: a clinicopathologic study.

PURPOSE: To describe clinical, imaging and histopathologic findings of congenital cystic eyes associated with intracranial malformations. METHODS: Retrospective, noncomparative, interventional, clinicopathologic case reports of two female children (ages 15 days and six months) who were found to have non-discernable eye globes at birth. The patients underwent complete clinical examination, imaging studies, surgical exploration and histopathological evaluation of the excised orbital cystic structures. RESULTS: The fellow socket in one patient was found to be anophthalmic and the fellow eye in the second patient was highly myopic. Clinical, imaging [ultrasonography, computerized tomography (CT) scan and magnetic resonance imaging (MRI)], and histopathologic evaluations were consistent with the diagnosis of congenital cystic eye in both cases. Intracranial abnormalities were found in both patients, requiring ventroperitoneal shunting. Orbital cysts in both patients were excised and no recognizable eye structures were identified at the time of surgery. Histopathologic study in each case revealed a cyst externally surrounded by dense fibrous connective tissue with the inner aspect of the cyst lined by primitive neuroglial tissue in one case and immature and dysplastic retinal elements in the other. No recognizable ocular structures or microphthalmos were identified in either case. Immunohistochemical staining for glial fibrillary acidic protein, neuron-specific enolase and neurofilament protein were positive without evidence of normal elements of cornea, lens, ciliary body, choroid or retina. CONCLUSION: Congenital cystic eye should be suspected in patients with an unrecognizable eye globe and the possible association with intracranial malformation investigated. Early recognition of the association may help in the diagnosis and treatment of anophthalmic socket and intracranial anomalies.

Outcome of treated orbital cellulitis in a tertiary eye care center in the middle East.

PURPOSE: To describe risk factors predisposing patients to orbital cellulitis and potential complications in patients treated at a tertiary eye care referral center in the Middle East. DESIGN: Noncomparative, interventional, retrospective case series. PARTICIPANTS: Patients diagnosed with orbital cellulitis. METHODS: A 15-year clinical review of patients with a diagnosis of orbital cellulitis referred to King Khaled Eye Specialist Hospital, an accredited (Joint Council on Accreditation of Healthcare Organizations, Washington, DC) tertiary care center in Riyadh, Saudi Arabia, was performed. Only those patients who had clinical signs and symptoms or radiologic evidence suggestive of orbital cellulitis were included in the study. MAIN OUTCOME MEASURES: Patient demographics, factors predisposing to orbital cellulitis, and resulting complications. RESULTS: A total of 218 patients (136 male, 82 female) fulfilling the diagnostic criteria for orbital cellulitis were identified. The average age of these patients was 25.7 years (range, 1 month-85 years). On imaging studies, there was evidence of inflammatory or infective changes to orbital structures; orbital abscesses were identified in 116 patients (53%). Sinus disease was the most common predisposing cause in 86 patients (39.4%), followed by trauma in 43 patients (19.7%). All patients received systemic antibiotic treatment before the identification of any responsible organisms. Of the 116 patients with orbital abscess, 101 patients (87%) required drainage. The results of cultures in patients in whom an orbital abscess was drained were positive for 91 patients (90%). The most common microorganisms isolated from the drained abscesses were Staphylococci and Streptococci species. Blood cultures were positive in only 4 patients from whom blood was drawn for cultures. Visual acuity improved in 34 eyes (16.1%) and worsened in 13 eyes (6.2%), including 9 (4.3%) eyes that sustained complete loss of vision, which was attributed to the delay in correct diagnosis and timely intervention (average 28 days vs. 9 days in patients with no loss of vision; P<0.05). There were 9 cases of intracranial extension of orbital abscesses that required either extended treatment with systemic antibiotics alone or in combination with neurosurgical intervention. Most patients received oral antibiotics on discharge for varying periods. There were 6 cases (2.7%) of strabismus and 4 cases (1.8%) of ptosis that persisted after treatment and resolution of orbital cellulitis. CONCLUSIONS: Untreated sinusitis and prior history of orbital trauma were the 2 major causes of orbital cellulitis in patients referred to a tertiary care eye center in the Middle East. Although rare, severe visual loss still remains a serious complication of delayed detection and intervention in most cases of orbital cellulitis.

Detection of Mycobacterium leprae in ocular tissues by histopathology and real-time polymerase chain reaction.

AIM: To report detection of leprosy in ocular tissue by histopathology and its confirmation by genetic analysis. METHODS: Excised tissue from a clinically-suspected ocular leprosy patient was processed and analyzed histopathologically. The DNA from the paraffin-embedded tissue was extracted, an 85 A-C intergenic region of Mycobacterium leprae was amplified using specific primers and analyzed by conventional as well as real-time polymerase chain reaction (RT-PCR). RESULTS: With periodic acid-Schiff-hematoxylin (PAS-H) staining the specimen showed presence of a thin fibrinous layer of inflammatory cells. The majority of the tissue was fibrovascular with extensive infiltration by histiocytes having reticulated cytoplasm. Modified PAS-H and acid-fast staining (AFS) showed the presence of several acid-fast organisms within the cytoplasm of histiocytes and mast cells. Conventional PCR showed a 250-bp DNA from excised conjunctival tissue, which was in agreement with the positive controls for M. leprae. Through RT-PCR, it was calculated that the suspected tissue had 44.68 pg of M. leprae DNA, which is 8937.06 genome copies of M. leprae. CONCLUSIONS: Presence of inflammatory cells and AFS bacilli in tissue presented a typical picture of leprosy. M. leprae DNA can be detected using RT-PCR in ocular tissues when acid-fast bacteria are seen in histopathological sections. And when the diagnosis of leprosy is inconclusive and acid-fast bacteria are seen, RT-PCR for M. leprae DNA could be used as a rapid confirmatory test to identify the presence of M. leprae and, therefore, the diagnosis of leprosy.

Epidemiology of giant-cell arteritis in an Arab population: a 22-year study.

OBJECTIVE: To study the epidemiology of biopsy-proven giant-cell arteritis (GCA) in an Arab population with clinical features suggestive of GCA. METHODS: Clinical records of 102 patients who underwent temporal artery biopsy (TAB) at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia from January 1983 to December 2004 were reviewed. RESULTS: Among the 56 men and 46 women who had TAB, 7 (6.8%) had biopsy-proven GCA. The mean (SD) age of the biopsy-positive group (71.7 (8.6) years) was higher than in the biopsy-negative group (65 (9.8) years; p = 0.005). None of the untreated patients with a negative TAB developed additional symptoms that are typical of GCA. CONCLUSION: The small absolute number of biopsy-proven cases of GCA implies a relatively low incidence of GCA in Arab population, confirming previous observations that GCA occurs primarily in the Caucasian population.

Severe ocular injuries from pointed door handles in children.

OBJECTIVE: To report severe ocular injuries caused by pointed door handles in children. DESIGN: Noncomparative, interventional, retrospective case series. METHODS: Clinical records of 15 patients who sustained severe ocular injuries from door handles were reviewed for place of trauma, presenting symptoms and signs, surgical procedures performed, and final outcome. MAIN OUTCOME MEASURES: Trauma caused by complications from the door handle injury, such as loss of vision and ocular and adnexal injuries, and treatment rendered. RESULTS: There were 12 boys and 3 girls with an average age of 7.8 years (range, 6-10 years). Place of trauma was at home in 12 children and in school in 3 children. Presenting visual acuity (VA) was 4/200 in 1 patient, light perception (LP) in 5 patients, and no light perception (NLP) in 9 patients. There were 9 eyelid or canalicular lacerations, 4 ruptured globes, and 14 optic nerve avulsions. All ruptured globes were repaired initially and eyelid and canalicular lacerations were repaired primarily within 24 hours of presentation. Average follow-up was 21 months (range, 1 month-8 years). Final VA was 20/30 in 1 patient, LP in 1 patient, and NLP in 13 patients. Eight eyes required enucleation for painful blind eye or to achieve optimal cosmesis. CONCLUSIONS: Pointed door handles installed at current heights may pose a significant risk of ocular and periocular injuries among young children.

Bacteriology of chronic dacryocystitis in a tertiary eye care center.

PURPOSE: To determine the current bacteriology of adult chronic dacryocystitis in a tertiary eye care center and compare it with previously reported studies. METHODS: Clinical and microbiological records of patients with diagnosis of chronic dacryocystitis between January 1999 and March 2002 were reviewed for age, sex, lacrimal sac side involved, and culture results. Patients younger than 16 years of age and patients who were receiving any systemic or topical antibiotics were excluded from the study. RESULTS: One hundred eighty-eight adult patients with an average age of 50.5 years (range, 16 to 91 years), who had a diagnosis of chronic dacryocystitis, were identified. The study was predominated by female subjects (65.4%). Of the cultures from the nasolacrimal sac, 183 (97.3%) were positive for bacteria, with an average of 2.3 (1 to 6) microorganisms. More than 2 microorganisms were present in 66.1% of the cultures, whereas a single microorganism was recovered from 33.9% of the cultures. The majority of microorganisms in our study were Gram-positive bacteria, representing 53.7% of the overall microorganisms cultured with a predominance of Staphylococcus species. Gram-negative bacteria were recovered from 26.0% of the specimens with predominance of Haemophilus influenzae. Anaerobic microorganisms were present in 19.1% of the samples. The most frequently isolated anaerobic microorganisms were Propionibacterium acne and Peptostreptococcus species. CONCLUSIONS: Several bacterial species may be involved in the pathogenesis of chronic dacryocystitis in adults, and the majority of patients harbor multiple microorganisms in their nasolacrimal sacs. The high rate of microorganism-positive lacrimal sac cultures suggests that adult patients should be treated for their infection before any intraocular surgery because of the potential risk of infection.

Blue light induces mitochondrial DNA damage and free radical production in epithelial cells.

Exposure of biological chromophores to ultraviolet radiation can lead to photochemical damage. However, the role of visible light, particularly in the blue region of the spectrum, has been largely ignored. To test the hypothesis that blue light is toxic to non-pigmented epithelial cells, confluent cultures of human primary retinal epithelial cells were exposed to visible light (390-550 nm at 2.8 milliwatts/cm2) for up to 6 h. A small loss of mitochondrial respiratory activity was observed at 6 h compared with dark-maintained cells, and this loss became greater with increasing time. To investigate the mechanism of cell loss, the damage to mitochondrial and nuclear genes was assessed using the quantitative PCR. Light exposure significantly damaged mitochondrial DNA at 3 h (0.7 lesion/10 kb DNA) compared with dark-maintained controls. However, by 6 h of light exposure, the number of lesions was decreased in the surviving cells, indicating DNA repair. Isolated mitochondria exposed to light generated singlet oxygen, superoxide anion, and the hydroxyl radical. Antioxidants confirmed the superoxide anion to be the primary species responsible for the mitochondrial DNA lesions. The effect of lipofuscin, a photoinducible intracellular generator of reactive oxygen intermediates, was investigated for comparison. Exposure of lipofuscin-containing cells to visible light caused an increase in both mitochondrial and nuclear DNA lesions compared with non-pigmented cells. We conclude that visible light can cause cell dysfunction through the action of reactive oxygen species on DNA and that this may contribute to cellular aging, age-related pathologies, and tumorigenesis.