Biomedical subjects

Guilherme Herrmann Matos

Publications and source records attributed to Guilherme Herrmann Matos.

5 recordsLinked to original sources

PubMed2006

[LASIK for high anisometropia in adults: case report].

PURPOSE: To evaluate the efficacy of the laser in situ keratomileusis (LASIK) technique in the reduction of anisometropy in adults, for whom conventional treatment was not successful. METHODS: A sequence of cases of three eyes of three adult patients, two females and one male, age ranging from 28 and 49 years (average 38.3 years), who underwent LASIK. Two patients were followed up for eighteen months and one for six months. RESULTS: Comparing the corrected visual acuity before surgery with the non-corrected visual acuity after surgery, one eye gained two lines of vision, one eye remained the same and one eye lost one line of vision. All eyes remained without spheric refraction, and astigmatism did not exceed -0.75 D after surgery. There has been an improvement in the symptoms of asthenopia in the three patients. CONCLUSION: The LASIK technique proved to be efficient in the correction of anisometropy in adults, improving visual accuity and asthenopia complaints, and leading to a similar refraction in both eyes.

Adult↗

PubMed2005

[Total refractive regression post-LASIK: case report].

Corticosteroids can increase intraocular pressure when administered topically, systemically and even when inhaled. They are routinely used after refractive surgeries to lower or prevent an inflammatory action. In this case history, we present a 36-year-old patient who had a total myopic regression two weeks after LASIK for low myopia, caused by steroid-induced ocular hypertension. The purpose of this report is to describe how the case was managed, the diagnostic hypothesis, and to stress the importance of intraocular pressure measurement after LASIK.

Adult↗

PubMed2005

[Ocular aspergillosis--case report].

Presence of fungus in the conjunctiva is a constant threat to the eyes, because these microorganisms, defined as opportunistic, may provoke severe ocular infections, in situations as low organic resistance, use of immunosuppressants, antibiotics and epithelial alteration. Our goal here is to report a case of ocular aspergillosis in an immunosuppressed patient where paroxysmal nocturnal hemoglobinuria was diagnosed. A 51-year-old immunosuppressed, thrombocytopenic patient was hospitalized with a diagnosis of paroxysmal nocturnal hemoglobinuria. On examination, she had a visual acuity of 20/40 in the right eye (RE) and light perception in the left (LE). She presented hyposphagma, bilateral conjunctival edema on biomicroscopy and had some multiple and circumscribed conjunctival abscesses in both eyes; clear cornea in both eyes. Fundoscopy of the RE did show any particularity, in the LE there was a smear hemorrhage. Computed tomograph showed a fat periocular infiltration. Magnetic resonance lead to the same finding, compatible with orbital cellulitis. Hemoculture showed Aspergillus growth and direct smears of conjunctival material was negative. There was great improvement while treating her with amphotericin B, but there was complete remission after using 5% natamicyn eye drops. Orbital infections caused by Aspergillus are uncommon, usually appearing in immunosuppressed patients. Frequently they progress insidiously, and can be confounded with other orbital processes. Immunological impairment can inhibit the expression of local and systemic symptoms, resulting in diagnostic confusion. The diagnosis is established by laboratory tests, but culture can be negative in spite of the classical presentation, making the beginning of treatment difficult. In these cases management starts according to the symptoms.

Amphotericin B↗

PubMedDate not supplied

[In vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses].

PURPOSE: To quantify and compare the in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to different intraocular lenses (IOLs). METHODS: Fourteen intraocular lenses were used in the experiment. Four of polymethylmethacrylate (PMMA), four of silicone, four of hydrogel and two of acrylic. Eight intraocular lenses were placed in eight test tubes containing 4 ml of Pseudomonas alcaligenes suspension, and six intraocular lenses were placed in six test tubes containing 4 ml of Staphylococcus epidermidis suspension. The bacterial suspension used for adherence tests was 10(8) colony-forming units per milliliter (CFU/mL) which corresponds to 0.5 in the scale of McFarland. The lenses were incubated at 37 degrees for two hours. After this, intraocular lenses were removed from the test tubes and dried twice with the use of distilled and sterile water. The material was spread on blood-agar for cultivation at 35-37 degrees C and was evaluated every 24 hours up to 72 hours. In the samples where there was bacterial growth, the colonies were counted using the conventional laboratory methods. All assays were performed in duplicate. RESULTS: Adherence of Staphylococcus epidermidis to PMMA intraocular lenses was lower than to hydrogel and silicone intraocular lenses. Adherence of Pseudomonas alcaligenes to hydrogel intraocular lenses was lower than to PMMA, acrylic and silicone intraocular lenses. CONCLUSIONS: Results suggest that in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses is influenced by type of material of the lens and by microorganism species. Bacterial adherence may play a role in the pathogenesis of some forms of endophthalmitis after cataract surgery. More in vitro and clinical studies are necessary to elucidate the mechanisms by which Staphylococcus epidermidis and Pseudomonas alcaligenes cause endophthalmitis.

Bacterial Adhesion↗

PubMedDate not supplied

[Tear antioxidant potential in young adults].

PURPOSE: To study the antioxidant status of human tears, stimulated by onion fumes and the possible influence of the life habits thereon were measured. METHODS: Subjects were ten healthy young adults, who answered a questionnaire about smoking, alcohol ingestion, fruit, vegetable, cereal, and vitamin intake and/or intake of other drugs, and physical exercise habits. Chemoluminescensce of luminol was used to analyze the total reactive antioxidant potential (TRAP), inhibition of piragollol was used to measure superoxide dismutase (SOD) and absorbance of H2O2 at 240 nm was used to identify catalase. RESULTS: Mean +/- SD value for total reactive antioxidant potential was 33.8+/-11.5 microM and for superoxide dismutase 10.8+/-1.9 U/mL. Catalase was not identified. Regular exercise was associated with increased total reactive antioxidant potential values (p=0.021), with a difference of 18.6 microM between individuals who exercise at least once a week and sedentary individuals. Male gender and total reactive antioxidant potential values were statistically associated (p=0.013), with a difference of 16.3 microM between genders. There was an association between smoking and increased superoxide dismutase values (p=0.041), with a difference of 3.3 U/mL between smokers of more than five cigarettes/day and non-smokers. Also, vitamin C intake and superoxide dismutase values were associated (p=0.018); the difference for vitamin C takers was 3.3 U/mL. CONCLUSION: Reflex tearing antioxidants were measurable in healthy young adults, and different variables apparently influenced their values.

Adult↗