Effect of axial length on retinal nerve fiber layer thickness in children

WOS: 000335377100021PubMed: 23918073Purpose: To investigate the effect of axial length on peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, hyperopic, and emmetropic eyes in children by Cirrus HD spectral-domain optical coherence tomography (OCT). Methods: Subjects were divided into 3 groups according to their refractive status: myopic (n = 36), emmetropic (n = 30), and hyperopic (n = 28) eyes. the RNFL thickness measurements were taken from the superior, inferior, nasal, and temporal quadrants in the peripapillary region by Cirrus HD OCT. Axial length was also determined for each patient. Results: the myopic eyes had thinner average RNFL and RNFLs of temporal, superior, nasal, and inferior quadrants than the hyperopic eyes (p1 0.05). Conclusions: We have shown that axial length and accordingly refractive status influenced peripapillary RNFL thickness measurements by Cirrus HD OCT in children. Therefore, to make a correct diagnosis of glaucoma or other optic neuropathies in children, either axial length-induced magnification effect should be corrected by ophthalmologists or the current Cirrus HD OCT database should be revised taking axial length into consideration

Plasma Homocysteine Levels in Dry Eye Patients

WOS: 000317467300009PubMed: 23132455Purpose: To compare plasma homocysteine levels between patients with dry eye disease and normal control subjects. Methods: Plasma homocysteine (enzyme immunoassay), vitamin B12, and folate levels were determined in 38 patients with dry eye and in 38 controls. Results: Characteristics of the dry eye and control groups were similar. the mean plasma homocysteine level was 16.38 +/- 6.98 mmol/L in the dry eye group and 14.39 +/- 5.11 mu mol/L in the control group (P = 0.10, t test). Hyperhomocysteinemia was present in the 43.9% of the dry eye patients and 33.3% of the controls (P = 0.43, chi(2) test). There were no statistical differences between dry eye and control groups regarding plasma vitamin B12 and folate levels (P = 0.72 and P = 0.69, respectively, t test). Conclusions: Plasma homocysteine levels in dry eye patients may be inadequate to give homocysteine a role in pathogenesis. However, in ocular diseases like glaucoma, plasma homocysteine levels are significantly higher, and associated dry eye disease may cause an additional increase in plasma homocysteine levels

Evaluation of Peripapillary Retinal Nerve Fiber Layer Thickness in Patients With Vitamin B12 Deficiency Using Spectral Domain Optical Coherence Tomography

WOS: 000318646600009PubMed: 23317171Purpose: To compare peripapillary retinal nerve fiber layer (RNFL) thicknesses measured by Cirrus HD optical coherence tomography (OCT) of patients with vitamin B12 deficiency with healthy controls and to evaluate the correlation between the peripapillary RNFL thickness and plasma vitamin B12 levels. Materials and Methods: Forty-five patients (19 male and 26 female) with a diagnosis of vitamin B12 deficiency (patient group) and 45 age-and sex-matched healthy subjects (control group) were consecutively enrolled in this study. Average, temporal, nasal, inferior, and superior quadrant peripapillary RNFL thicknesses of each subject were obtained using the Cirrus HD OCT. Disc area (DA) and rim area (RA), central subfield thickness (CST), cube volume (CV), and cube average thickness (CAT) were also measured. Results: Mean age of each group was 33.1 +/- 6.5 years (range: 21-45 years). Mean plasma vitamin B12 level was 114.8 +/- 34.0 pg/mL in the patient group and was 405.1 +/- 20.0 pg/mL in the control group (p < 0.001). the patient and control groups were similar regarding axial length, plasma folate levels, DA, RA, CST, CV, CAT, and RNFL thicknesses in superior, nasal, and inferior quadrants. However, average RNFL and RNFL in temporal quadrant were significantly thinner in the patient group than in the control group (p = 0.013 and p < 0.001, respectively). in addition, temporal (r = 0.356, p = 0.001) and average (r = 0.212, p = 0.045) peripapillary RNFL thicknesses were correlated with plasma vitamin B12 levels. Conclusion: We have shown that, as in other non-glaucomatous optic neuropathies, temporal quadrant RNFL thickness was thinner in patients with vitamin B12 deficiency and it was correlated with plasma vitamin B12 levels. Further studies are warranted to clarify the clinical relevance of these findings and the effects of vitamin B12 replacement therapy

Complication of Peribulbar Block: Brainstem Anaesthesia

WOS: 000410003200009PubMed: 28868171Peribulbar block is used to obtain anaesthesia and akinesia of the eye by injecting a local anaesthetic around the musclecone. A patient scheduled for cataract surgery received peribulbar block with 6 mL of 2% lidocaine hydrochloride. Following the injection, confusion, hypotension and dilatation of the contralateral pupil rapidly progressed to loss of consciousness and respiratory arrest. the patient was intubated and mechanically ventilated for 30 min. the patient regained her consciousness, was extubated and transferred to the intensive care unit for further follow-up. Although brainstem anaesthesia because of peribulbar block is very rare, this procedure should be performed with complete monitorisation and resuscitation equipment