Pupillary capture following sutureless scleral-fixated intraocular lens in children with Marfan syndrome.

AIM: To compare the clinical outcomes between two approaches for sutureless scleral-fixated intraocular lens (SFIOL) in children with Marfan syndrome (MFS). METHODS: The study included 15 children (26 eyes) with lens subluxation due to MFS. These children underwent lensectomy, anterior vitrectomy, and sutureless SFIOL. According to the position of placement of intraocular lens (IOL) haptics, two study groups were reviewed for best corrected visual acuity (BCVA) and postoperative complications: group A, 14 eyes with haptics fixated at 2.0 mm from the limbus; group B, 12 eyes with the haptics fixated at 2.5 mm from the limbus. RESULTS: The mean axial length for all patients was 25.66±2.35 mm. Postoperative BCVA in logMAR were significant improved in both groups (0.77±0.32 to 0.17±0.12 in group A, 0.66±0.25 to 0.24±0.12 in group B, both P<0.001) while no significant difference between two groups (P>0.05). Pupillary capture was main postoperative complication, occurring between 3d and 18mo. It occurred in 7 eyes in group A and one eye in group B (P=0.02). CONCLUSION: Sutureless SFIOL is an effective treatment approach for lens subluxation in children with MFS. Pupillary capture is the main postoperative complication. Fixated IOL haptics at 2.5 mm from the limbus can reduce the occurrence of pupillary capture.

Alpha-crystallin promotes rat olfactory ensheathing cells survival and proliferation through regulation of PI3K/Akt/mTOR signaling pathways.

Transplantation of cultured olfactory ensheathing cells (OECs) into lesions can promote axonal regeneration. However, the acutely injured CNS environment affects the survival and proliferation of OECs which might impair its therapy effects. To investigate whether α-crystallin can promote the survival and proliferation of OECs, OECs were cultured with α-crystallin. The survival of OECs was assessed by counting the numbers of p75-labeled OECs. Cellular proliferative activity was estimated by flow cytometry and quantification of BrdU-labeled cells. Phosphorylated p85, Akt and mammalian target of rapamycin (mTOR) were detected when OECs were culture for 7 days. Our results showed that the numbers of p75-labeled or Brdu-labeled OECs in α-crystallin group were much more than that in control group. And α-crystallin increased the phosphorylation of both p85, Akt and mTOR. LY294002 abrogated the ability of α-crystallin to phosphorylate Akt and mTOR, and decreased the percentage of cells in S and G2/M stage which were treated with α-crystallin. These findings indicated that α-crystallin positively regulated the activation of PI3K/Akt/mTOR signaling pathway and promote the proliferation and survival of cultured OECs.

Transplanted olfactory ensheathing cells reduce retinal degeneration in Royal College of Surgeons rats.

PURPOSE OF THE STUDY: Retinitis pigmentosa (RP) is a group of genetic disorders and a slow loss of vision that is caused by a cascade of retinal degenerative events. We examined whether these retinal degenerative events were reduced after cultured mixtures of adult olfactory ensheathing cells (OECs) and olfactory nerve fibroblasts (ONFs) were transplanted into the subretinal space of 1-month-old RCS rat, a classic model of RP. MATERIALS AND METHODS: The changes in retinal photoreceptors and Müller cells of RCS rats after cell transplantation were observed by the expression of recoverin and glial fibrillary acidic protein (GFAP), counting peanut agglutinin (PNA)-positive cone outer segments and calculating the relative apoptotic area. The retinal function was also evaluated by Flash electroretinography (ERG). To further investigate the mechanisms, by which OECs/ONFs play important roles in the transplanted retinas, nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and basic fibroblast growth factor (bFGF) secretion of the cultured cells were analyzed by ELISA. The ability of OECs/ONFs to ingest porcine retinal outer segments and the amount of phagocytosis were compared with retinal pigment epithelium (RPE) cells. RESULTS: Our research showed that the transplantation of OECs/ONFs mixtures restored recoverin expression, protected retinal outer segments, increased PNA-positive cone outer segments, reduced caspase-positive apoptotic figures, downregulated GFAP, and maintained the b-wave of the ERG. Cultured OECs/ONFs expressed and secreted NGF, BDNF, and bFGF which made contributions to assist survival of the photoreceptors. An in vitro phagocytosis assay showed that OECs, but not ONFs, phagocytosed porcine retinal outer segments, and the phagocytic ability of OECs was even superior to that of RPE cells. CONCLUSIONS: These findings demonstrate that transplantation of OECs/ONFs cleaned up the accumulated debris in subretinal space, and provided an intrinsic continuous supply of neurotrophic factors. It suggested that transplantation of OECs/ONFs might be a possible future route for protection of the retina and reducing retinal degeneration in RP.

Temporal and spatial characteristics of cone degeneration in RCS rats.

PURPOSE: The temporal and spatial characteristics of cone degeneration in the Royal College of Surgeons (RCS) rat were studied to provide information for treatment strategies of retinitis pigmentosa. METHODS: Nonpigmented dystrophic RCS rats (RCS) and pigmented nondystrophic RCS rats (controls) were used. Cone processes were visualized with peanut agglutinin (PNA). RESULTS: Cone development appears to have been completed by postnatal day 21 (P21) in both the RCS and control rats. Signs of cone degeneration were obvious by P30, with shorter outer segments (OSs) and enlarged inner segments (ISs). At that time, 81.7% of the cones retained stained ISs. The rate of IS density decline was slower in the peripheral, nasal, and superior retina, and only 43.6% of the cones with ISs were present at P45. By P60, PNA-labeled cone ISs were distorted and restricted to the peripheral retina, and by P90, few cone pedicles were detected. CONCLUSIONS: Our findings indicate that therapeutic strategies aimed at rescuing cones in the degenerating retina should be applied before P21 and no later than P45 while substantial numbers of cones retain their ISs. Either the middle or peripheral regions of the nasal and superior retina are the best locations for transplantation strategies.

Transplanted olfactory ensheathing cells reduce the gliotic injury response of Müller cells in a rat model of retinitis pigmentosa.

Retinitis pigmentosa leads to progressive visual loss and blindness. Until now there has been no effective therapy. Experimental studies have shown that transplantation of olfactory ensheathing cells into CNS lesions reorganizes the glial scar and stimulates axon regeneration. We now report that cultured syngeneic adult rat olfactory ensheathing cells transplanted into the subretinal space of pigmented Royal College of Surgeon rats survived for a minimum of 8weeks, migrated into surrounding space, and suppressed the gliotic injury response of the Müller cells. Further investigation of intraretinal transplantation of olfactory ensheathing cells may suggest a possible future route for protection of the retina in retinitis pigmentosa.

Spectral-domain optical coherence tomography in patients with congenital nystagmus.

AIM: To study macular features in patients with congenital nystagmus and to assess the utility of spectral-domain optical coherence tomography (SD-OCT) in nystagmus. METHODS: The macular areas of 51 outpatients with congenital nystagmus were examined using SD-OCT. Morphological changes in the retinal layers of the macular area were analysed. RESULTS: Macular images were successfully obtained with SD-OCT from 50 (98%) patients. Patients with ocular albinism mainly have macular hypoplasia, abnormal foveal depression, and increased foveal thickness with persistence of an inner nuclear layer, an inner plexiform layer, a ganglion cell layer and a nerve fiber layer. Macular morphology similar to albinism was observed in three patients with idiopathic macular hypoplasia. The OCT findings of cone dystrophy included unclear, disrupted or invisible photoreceptor outer segment/inner segment in the fovea; fusion, thickening and uneven reflection of the outer segment/inner segment with external limiting membrane. Some patients with congenital idiopathic nystagmus showed normal macular morphology and structure, and others showed indistinct macular external limiting membrane reflection. CONCLUSION: SD-OCT is an effective and reliable method to detect the macular morphology of congenital nystagmus patients. This technique has diagnostic value in particular for patients with macular hypoplasia and cone cell dystrophy with no distinct abnormality on fundoscopy.