Accelerated Corneal Cross-linking in Pediatric Patients with Progressive Keratoconus: 12-Month Follow-up Results.

PURPOSE: To evaluate effectiveness and safety of accelerated corneal cross-linking (CXL) in the treatment of keratoconus in pediatric patients. SETTING: Tertiary care hospital. DESIGN: Retrospective observational study. METHODS: In this study, case series of patients 18 years old or younger with progressive keratoconus who underwent accelerated CXL were observed. All consecutive patients underwent accelerated CXL with setting of 9 mW/cm2 for 10-minute Ultraviolet-A radiation, corresponding to a total dose of 5.4 J/cm2. Preoperative and 12-month postoperative data including uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BDVA), keratometry (K) measurements, mean spherical, and cylindrical refraction were evaluated. RESULTS: The group consisted of 28 eyes from 14 patients (10 males and 4 females). Mean age of the patients was 16.9 years (11-18 years). UDVA did not change significantly from 0.71 ± 0.54 to 0.65 ± 0.43 logMAR (P = 0.41). BDVA improved significantly from 0.30 ± 0.35 to 0.21 ± 0.34 (P = 0.006). The steep K-value decreased from 48.4 ± 4.3 to 48.0 ± 4.6 diopters, but there was no significant change in steep K-value (P = 0.35). There was no significant change in flat and mean K-value (P > 0.05). Mean spherical and cylindrical refraction were not significantly altered (P > 0.05). One patient with vernal keratoconjunctivitis showed sterile peripheral corneal infiltrates. Patient was treated with topical corticosteroids, antibiotics, and artificial tears. CONCLUSION: The findings revealed that accelerated CXL is an effective and safe procedure that halts the progression of keratoconus in pediatric patients.

Scoring system evaluation for orbital exenteration in patients with rhino-orbito-cerebral mucormycosis.

PURPOSE: To evaluate our patients with rhino-orbito-cerebral mucormycosis according to a new scoring system and to compare those who underwent orbital exenteration persuant to a new threshhold. METHODS: Mucormycosis is a fungal disease that can be of acute onset, aggressive, and angioinvasive. Aggressive surgical debridement, long-term systemic antifungal therapy, and treatment of underlying predisposing factors are essential to the treatment. However, orbital exenteration is a very difficult decision to make, particularly in patients with orbital involvement, because there is little information in the literature, resulting in limited support for making this aggressive surgical decision. In this study, our 43 cases of mucormycosis were evaluated in terms of orbital exenteration using a scoring system (including clinical signs and symptoms, ophthalmoscopic findings, and radiologic results) developed by Shah et al., which establishes indications for orbital exenteration in mucormycosis. RESULTS: According to our study, if the threshold score for exenteration is 19.0, the sensitivity was 100% and specificity was 97%, providing better results than the 23.0 threshold score determined by the reference study for exenteration. When these two score thresholds were compared, there was a statistically significant difference. CONCLUSION: We believe that this scoring system may be beneficial to use for orbital exenteration in patients with mucormycosis. Prospective studies in large case series are required to determine the most appropriate threshold score.

The effects of magnetic field on the biomechanics parameters of soleus and extensor digitorum longus muscles in rats with streptozotocin-induced diabetes.

BACKGROUND: The aim of this study was to determine the effects of the magnetic field (MF) on the isometric contractile characteristics of the soleus and extensor digitorum longus (EDL) muscles in rats both with and without diabetes. METHODS: Biomechanical parameters were recorded in vitro from Wistar rats without diabetes (Group I, n=20), rats without diabetes exposed to MF (Group II, n=20), rats with streptozotocin-induced diabetes (Group III, n=20), and rats with diabetes exposed to MF (Group IV, n=20). Muscle strips were taken from the distal tendon soleus and EDL muscles of rats killed by decapitation. The muscles were hung in organ baths containing Krebs solution (pH 7.4) with a gas mixture of 95% O2 and 5% CO2. Then the muscles were triggered to direct supramaximal stimulation with 0.05 Hz frequency square pulses for periods of 0.5 ms to obtain control values. The contractile parameters were also determined for two muscles of the four groups. Later, the tension-frequency relationship was determined by applying stimulating pulses of 10, 20, 50, and 100 Hz to the muscles. RESULTS: Diabetes caused a certain amount of decrease in the contractile force of the two muscles compared with that of control values. However, MF increased the contractile force of the two muscles in rats both with and without diabetes. The isometric contraction forces obtained by different stimulating frequencies showed a significant linear increase in the tetanic contraction (P<0.05). Diabetes increased the contraction time of the isometric twitch tension compared with that of the control group with a statistically significant difference (P<0.05). MF decreased the contraction time of the two muscles of rats without diabetes (P<0.05) but increased that of rats with diabetes (P>0.05). CONCLUSION: In our study, these results suggest that MF exposure regulates the isometric contractile characteristics of the soleus and EDL muscles of rats with diabetes, positively.

Value of color Doppler ultrasonography in the evaluation of orbital vascular flow in end-stage renal disease patients undergoing hemodialysis.

PURPOSE: To evaluate choroidal and retinal vascular flow dynamics by means of color Doppler ultrasonography in patients with end-stage renal disease undergoing hemodialysis and to compare these findings with healthy controls. MATERIAL AND METHODS: Color Doppler ultrasonography and spectral analysis of nasal and temporal posterior ciliary and central retinal artery flow of both eyes were performed in 20 patients (40 eyes) and 22 controls (44 eyes) to assess peak systolic flow velocity, end-diastolic flow velocity, and resistive indices (RI). Patients with hypertension, diabetes mellitus, and any cardiac pathology were not included in the study. A general ophthalmologic examination was performed in all patients and controls. RESULTS: The average peak-systolic and end-diastolic blood flow velocities of nasal (12.88 +/- 4.91/6.88 +/- 3.26) and temporal (15.22 +/- 9.59/6.41 +/- 3.97) posterior ciliary artery and central retinal artery (14.94 +/- 8.38/6.7 +/- 4.13) in patients were significantly higher than the corresponding values of the controls. The RI values of nasal (0.52 +/- 0.10) and temporal (0.58 +/- 0.12) posterior ciliary artery and central retinal artery (0.55 +/- 0.11) in patients with end-stage renal disease undergoing hemodialysis were significantly lower than in the controls. CONCLUSION: Choroidal and retinal blood flow velocities are higher and RI values for all three vessels lower in patients with end-stage renal disease undergoing hemodialysis compared to healthy controls. These alterations may be related to either increased choroidal blood flow or vasoconstriction of the proximal vessels.

Tear function tests and conjunctival impression cytology before and after hormone replacement therapy in postmenopausal women.

PURPOSE: To investigate the effect of hormone replacement therapy (HRT) on postmenopausal tear function and the conjunctival epithelium. METHODS: Schirmer I-Jones test, tear film break-up time (BUT), and impression cytology findings were analyzed in 34 eyes of 17 women who were at least two years postmenopausal and not taking HRT: This series of tests was repeated after three months on HRT. RESULTS: The patients' average age was 53.82 +/- 3.6 years, and the mean time postmenopause was 35.29 +/- 11.59 months. There was no significant difference in the Schirmer I-Jones test results before and after three months of HRT (p > 0.05). However, the BUT (p < 0.05) and impression cytology (p < 0.05) findings were significantly affected by HRT. CONCLUSIONS: HRT may alleviate postmenopausal dry eye symptoms by increasing goblet cell density.

Pars plana vitrectomy in ocular Behçet's disease.

PURPOSE: To evaluate the results of pars plana vitrectomy in Behçet patients with dense vitreous opacities, and its effect on intraocular inflammatory episodes and visual prognosis. METHODS: The study group consisted of nine patients (one eye in eight patients, both eyes in one) with Behçet's disease who underwent pars plana vitrectomy because of dense vitreous opacification. The indications for vitrectomy, the effect of vitrectomy on the frequency of severe intraocular inflammatory episodes, and visual prognosis were investigated in these patients. All the patients were male, and their ages ranged between 28-45 years. Combined lensectomy was performed on those with complicated cataracts. The postoperative follow-up was between 12-66 months. RESULTS: In all of the patients preoperative visual acuity was hand motions. Postoperatively there was no change in vision in five eyes, however visual acuity improved in five eyes, between counting fingers and 0.4. None of the patients showed any severe postoperative intraocular inflammatory episodes, and phthisis did not develop in any of the patients. CONCLUSION: In this study, pars plana vitrectomy was found to have a beneficial effect on the prognosis of vision. There was also a decrease in the frequency of severe intraocular inflammatory episodes in patients with Behçet's disease with severe vitreous opacities, who did not respond to maximum medical treatment. However, further studies on larger groups should be performed in order to confirm the findings of this study.

Deposition profile of antibacterial anodic silver in root canal systems of teeth.

Electrically activated silver was shown to have an antibacterial effect in vitro and in vivo. In this study the effect of placing a silver anode in the root canal systems of teeth was examined to establish a base for treatment of infected teeth. Pure silver wires were placed in the main canals of extracted human teeth (n = 26) whose roots were partly submerged in a lactated Ringer's solution. Seventeen microamperes of anodic direct current were applied to one group of silver wires (n = 15) for 4 days. Then the wires were removed and the roots of both group teeth were cut into six sections and demineralized Silver concentrations of the root sections and their bathing solutions were measured with an atomic absorption spectrophotometer. In the anode group, the electrically activated silver concentrations (range, 1-30 micrograms/microL) exceeded the antibacterial levels (minimum inhibitory concentration, 0.1 micrograms/microL Ag) in all sections, particularly in the middle and lower sites of the root. The amount of anodic silver that leaked out of the root was found as to be 0.4 +/- 0.2 micrograms/microL in the fluid medium. This was 10 to 100-fold higher than that found in the nonactivated controls.