Objective To observe the retinal ultrastructure of the human fetal at the age of 9 months, and to investigate the clinical significance of the observation on retinal neuron development during the prenatal period.Methods Four human fetal eyes of 2 fetus at the gestational age of 9 months, including 1 at 35 and the other at 36 weeks, were obtained after termination of pregnancy due to trauma. The gestational ages of the fetus were estimated according to both last menstrual period (LMP) of the pregnant women and the weight/crownheel length of fetus at the delivery. From each eyeball, 4 pieces of retina at the posterior pole were obtained and observed after specimens handling according to the procedure of routine electron microscopy. Eight pieces of retina which were randomly selected from total of 16 pieces of retina in each group were processed and observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Permissions from pregnant women and family members were guaranteed.Results At the gestational age of 9 months, the outer nuclear layer of fetal retina contained 5 to 6 layers of photoreceptor cells (PRC), and sphericallike membrane structures were found outside of the outer limiting membrane (OLM). Among many tightaligned inner segments of PRCs there was zonula adherens of OLM, mitochondrias at inner side of OLM, and cilium at outer side of OLM. Outer segment of PRCs were short and contained a few irregularly arranged disc membrane. Some PRC had a multishaped nucleus in which equal amount of euchromatin and heterochromatin. There were only few and thin axon branches from photoreceptor cells, and very few axons contacted with inner nuclear layer (INL) and no typical synapse was found. The INL contained 4 to 5 layers of cell bodies, in which many cellular nuclear had uneven density of euchromatin and heterochromatin; some were lobulated nucleus with clear karyotheca. In inner plexiform layer (IPL), the nerve cells had small branches, and only little connection among the synapses and few synapse structures were found. Although not many retinal ganglion cells (RGC) existed,RGC had both intact cell membrane and some rough endoplasmic reticulum (RER).The karyotheca of RGC had double-layers structures, and the nucleus was mainly consisted of euchromatin. Internal limiting membrane (ILM) had doublelayer membrane structures, and the wellarranged nerve fiber layer was located at the outer side of ILM, with some micropores on the surface. Conclusions At the gestational age of 9 months, all layers of the human retinal has been formed, but some cell structure and cell connections are not yet mature, suggesting that at this time of period, human retina is still at an important stage of developing and remodeling.
Objective To observe the efficacy of lamellar hole-associated epiretinal proliferation (LHEP) flap insertion and autologous blood for degenerative type lamellar macular hole (LMH). Methods Retrospective case review. Twenty-eight eyes of 28 patients with LMH were enrolled in this study. There were 2 males (2 eyes) and 26 females (26 eyes). Best corrected visual acuity (BCVA), medical optometry, slit-lamp biomicroscop, indirect ophthalmoscope, spectral domain optical coherence tomography, b-scan ultrasonography and axial length detection were performed on all patients. Logarithm of the minimum angle of resolution (logMAR) was used to calculate visual acuity. There were 10 eyes (35.7%) with degenerative type LMH (flap insertion group) and LHEP. There were 18 eyes (64.3%) with tractional type LMH (general group). The differences of BCVA, AL, horizontal hole diameter from retina and lens state between two groups were not significant (P＞0.05). The differences of horizontal hole diameter of internal limiting membrane (ILM), central foveal thickness (CFT) and integrity of ellipsoidal zone between two groups were significant (P＜0.05). LHEP flap insertion and autologous blood without ILM peeling were used in eyes of flap insertion group. Vitrectomy combined ILM peeling were used in eyes of general group. The follow-up was ranged from 3 to 14 months. The changes of CFT, central foveal form and logMAR BCVA were observed. Results At latest follow-up, the BCVA of flap insertion group and general group were 0.34±0.27, 0.31±0.29; which significantly better than the preoperative BCVA (Z=−3.519, −4.945; P＜0.001). The CFT of flap insertion group and general group were (200.10±58.78), (226.61±70.49) μm. There was no difference between pre- and post-operative CFT in eyes of general group (Z=−1.455, P=0.146). There was significant difference between pre- and post-operative CFT in eyes of flap insertion group (Z=−2.798, P=0.005). In flap insertion group, regular recovery of the foveal contour occurred in 9 eyes (90.0%), improvement in 1 eyes (10.0%). In general group, regular recovery of the foveal contour occurred in 10 eyes (55.6%), improvement in 8 eyes (44.4%). The closure rate of LMH were 100% both in two groups. Conclusion LHEP flap insertion and autologous blood is an effective treatment of degenerative type LMH.