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Purpose To evaluate the changes in fundus parameters in patients with Alzheimer’s type dementia (ATD) using optical coherence tomography angiography (OCTA), to record flash electroretinograms using the RETeval system and to explore changes in retinal function.Methods Twenty-nine patients with ATD and 26 age-matched normal subjects were enrolled. All subjects underwent OCTA scans to analyse the superficial retinal vessel parameters in the macular area, including the vascular length density, the vascular width density and the area of foveal avascular zone (FAZ), as well as the choroidal thickness. The differences between the patients with ATD and the normal control group were compared and explored the relevant factors affecting vessel parameters. We also recorded the flash electroretinograms (ERG) using the RETeval system and intended to explore changes in retinal function by analysing the ERG image amplitude in patients with ATD.Results The vessel parameters and average choroid thickness in the macular area of the ATD group was less than the control group, The FAZ area was statistically significantly enlarged in the ATD group. These parameters were correlated with the Mini-Mental State Examination (MMSE) score and the Montreal Cognitive Assessment (MoCA).Conclusions Patients with Alzheimer’s type dementia exhibit decreases in the parameters associated with fundus. In addition, these indicators significantly correlated with the MMSE score and the MoCA score. OCTA may be an adjunct tool with strong potential to track changes in the diagnosis and monitoring the progression of the disease.

Background Bardet–Biedl syndrome (BBS) is a very rare autosomal recessive genetic disease with multiple manifestations including the ocular system. Aim This study presents different electrophysiological and clinical findings in three female patients with BBS. Patients and methods 3 female patients (9, 10 and 16 years old) with BBS were complaining of progressive visual loss. Full ophthalmological examination, optical coherence tomography (OCT) and various electrophysiological tests were performed to the 3 cases. Results The fundoscopic findings in all three patients did not show evidence of obvious characteristic signs of retinitis pigmentosa. They presented clinically with atypical form of pigmentary retinal dystrophy. Flash electroretinogram showed severe form of Rod-cone dystrophy in the 3 cases associated with macular dysfunction evident by reduced amplitude and increased implicit time of P1 wave of the multifocal electroretinogram in all rings. The pattern electroretinogram was with poor formed P50 wave. Pattern visual evoked potential showed prolonged latency and reduced amplitude of P100 wave in large and small checks. Conclusion Very reduced flash and multifocal electroretinogram is a Characteristic electrophysiological finding in BBS, which may precede the funduscopic changes, electrophysiological tests may help in the early diagnosis of such cases.

Purpose Glaucoma is a multifactorial disease, causing retinal ganglion cells (RGCs) and optic nerve degeneration. The role of diabetes as a risk factor for glaucoma has been postulated but still not unequivocally demonstrated. The purpose of this study is to clarify the effect of diabetes in the early progression of glaucomatous RGC dysfunction preceding intraocular pressure (IOP) elevation, using the DBA/2J mouse (D2) model of glaucoma. Methods D2 mice were injected with streptozotocin (STZ) obtaining a combined model of diabetes and glaucoma (D2 + STZ). D2 and D2 + STZ mice were monitored for weight, glycemia, and IOP from 3.5 to 6 months of age. In addition, the activity of RGC and outer retina were assessed using pattern electroretinogram (PERG) and flash electroretinogram (FERG), respectively. At the end point, RGC density and astrogliosis were evaluated in flat mounted retinas. In addition, Muller cell reactivity was evaluated in retinal cross-sections. Finally, the expression of inflammation and oxidative stress markers were analyzed. Results IOP was not influenced by time or diabetes. In contrast, RGC activity resulted progressively decreased in the D2 group independently from IOP elevation and outer retinal dysfunction. Diabetes exacerbated RGC dysfunction, which resulted independent from variation in IOP and outer retinal activity. Diabetic retinas displayed decreased RGC density and increased glial reactivity given by an increment in oxidative stress and inflammation. Conclusions Diabetes can act as an IOP-independent risk factor for the early progression of glaucoma promoting oxidative stress and inflammation-mediated RGC dysfunction, glial reactivity, and cellular death.

Although α6-contaning (α6*) nicotinic acetylcholine receptors (nAChRs) are densely expressed in the visual system, their role is not well known. We have characterized a family of toxins that are antagonists for α6β2* receptors and used one of these [RDP-MII(E11R)] to localize α6* nAChRs and investigate their impact on retinal function in adult Long-Evans rats. The α6*nAChRs in retinal tissue were localized using either a fluorescently tagged [RDP-MII(E11R)] or anti-α6-specific antibodies and found to be predominantly at the level of the ganglion cell layer. After intraocular injection of RDP-MII(E11R) in one eye and vehicle or inactive MII in contralateral eyes as controls, we recorded flash electroretinograms (F-ERGs), pattern ERGs (P-ERGs), and cortical visual-evoked potential (VEPs). There was no significant difference in F-ERG between the RDP-MII(E11R)-treated and control eyes. In contrast, P-ERG response amplitude was significantly reduced in the RDP-MII(E11R)-injected eye. Blocking α6* nAChRs at retinal level also decreased the VEP amplitude recorded in the visual cortex contralateral to the injected eye. Because both the cortical and inner retina output were affected by RDP-MII(E11R), whereas photoreceptor output was preserved, we conclude that the reduced visual response was due to an alteration in the function of α6* nAChRs present in the ganglion cell layer.-Barloscio, D., Cerri, E., Domenici, L., Longhi, R., Dallanoce, C., Moretti, M., Vilella, A., Zoli, M., Gotti, C., and Origlia, N. In vivo study of the role of α6-containing nicotinic acetylcholine receptor in retinal function using subtype-specific RDP-MII(E11R) toxin.