Combining FES and Exoskeletons in a Hybrid Haptic System for Enhancing VR Experience.

Robotic technology and functional electrical stimulation (FES) have emerged as highly effective rehabilitative techniques for individuals with neuromuscular diseases, showcasting their ability to restore motor functions. Within the proposed study, we developed and tested a new hybrid controller combining an upper-limb exoskeleton with FES to enhance haptic feedback when performing task-oriented and bimanual movement, like pick-and-place, in a virtual environment. We investigated the performance of the proposed approach on eight unimpaired participants providing haptic feedback either only by the exoskeleton or by the hybrid system. The hybrid control presents two different modalities, assistive and resistive, to modulate the perception of the load. FES intensity is calibrated to the subjects' biomechanical properties and it is adjusted in real-time according to the real-time motion of the upper limbs. Experimental results highlighted the ability of the hybrid control to improve kinematic performance: in both hybrid modalities subjects reduced the target matching error(values between 0.048±0.007 m and 0.06±0.006 m) without affecting the normal motion smoothness (SPARC values in the hybrid conditions range from -2.58±0.12 to -3.30±0.13). Moreover, the resistive approach resulted in greater metabolic consumption (1.04±0.03 W/kg), indicating a more realistic experience of lifting a virtual object through FES that increased the perceived weight. The innovation in our hybrid control relies on the modulation of muscular activation during manipulation tasks, which could be a promising approach in the clinical treatment of neuromuscular diseases.

A literature review of hypertensive retinopathy: systemic correlations and new technologies.

OBJECTIVE: Hypertensive retinopathy (HR) is the most common ocular manifestation of systemic arterial hypertension. This paper aims to summarize the current knowledge of HR, reviewing its classical features, such as epidemiology, pathophysiology, clinical manifestations, classifications, management and the most significant systemic correlations. We also provide an update on the latest advances in new technologies focusing on novel instrumental classifications. MATERIALS AND METHODS: A literature search was performed to identify articles regarding HR listed in Embase, PubMed, Medline (Ovid) and Scopus database up to 1 December 2021. The reference lists of the analyzed articles were also considered a source of literature information. The following keywords were used in various combinations: hypertensive retinopathy, hypertension and eye, hypertensive retinopathy and systemic correlations, optical coherence tomography (OCT) and hypertensive retinopathy, optical coherence tomography angiography (OCTA) and hypertensive retinopathy, adaptive optics (AO) and hypertensive retinopathy. The authors analyzed all English articles found using the aforementioned keywords. All the publications were thoroughly reviewed to create a detailed overview of this issue. RESULTS: HR signs have a significative association with cardiovascular, cerebrovascular and other systemic diseases. Patients with arteriosclerotic changes and, at the same time, severe HR, are at increased risk for coronary disease, peripheral vascular disease, stroke and dementia. HR is even now diagnosed and classified by its clinical appearance on a fundoscopic exam that is limited by interobserver variability. New technologies, like OCT, OCTA, AO and artificial intelligence may be used to develop a new instrumental classification that could become an objective and quantitative method for the evaluation of this disease. They could be useful to evaluate the subclinical retinal microvascular changes due to hypertension that may reflect the involvement of other vital organs. CONCLUSIONS: The eye is the only organ in the human body where changes in the blood vessels due to systemic hypertension can be studied in vivo. All doctors should be familiar with this disease because it has been largely demonstrated that signs of HR are correlated to patient's health and mortality. Researchers should develop a new common, standardized, and objective method to assess hypertensive retinal changes; new technologies may have a significant role in this field. This review takes most of the literature published so far, including the OCTA studies in order to stimulate new points of reference to standardize parameters and new diagnostic markers of this disease.

Bilateral Retinal Angiomatous Proliferation in a Variant of Retinitis Pigmentosa.

PURPOSE: To describe the first case of bilateral retinal angiomatous proliferation (RAP) in a patient with a variant of retinitis pigmentosa (RP). CASE REPORT: An 85-year-old man with RP presented with visual acuity decrease and metamorphopsia in the left eye (LE). Fundus examination revealed typical signs of RP in both eyes, associated with intraretinal macular hemorrhage in the LE. Multimodal imaging, using Colour fundus Photography, Fluorescein (FA), and Indocyanine Green Angiography (ICGA) as well as Spectral-Domain Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA), revealed a type 3 neovascular lesion in the involved eye. Genetic testing (NGS analysis) was performed to search for genetic variants correlated with the disease phenotype displayed by the patient. The patient was treated with intravitreal injections of bevacizumab, according to a fixed protocol of bimonthly injections plus a booster dose at second month. After 9 months, he was referred for visual acuity decrease and metamorphopsia in the fellow eye, where SD-OCT/OCTA showed a type 3 neovascular lesion in the right eye (RE). He was scheduled for intravitreal injections of bevacizumab. In both eyes, treatment with intravitreal bevacizumab was successful.

Aflibercept in persistent neovascular AMD: comparison of different treatment strategies in switching therapy.

PurposeTo evaluate the effects of aflibercept administered according to a pro re nata (PRN) or Fixed Regimen to patients with neovascular AMD and persistent intraretinal/subretinal fluid (IRF/SRF) despite three consecutive ranibizumab injections.MethodsPatients were switched to aflibercept injection (IVA) administered according to a PRN or to a fixed regimen for 1 year in two different retina centers. At baseline each patient underwent a complete ophthalmologic evaluation, including best-corrected visual acuity assessment (BCVA ETDRS chart), fluorescein, and indocyanine green angiography and OCT.ResultsEach group included 36 eyes. After 1 year the PRN group showed BCVA stabilization (63 vs 60 letters, P=0.33), whereas fixed regimen group showed significant BCVA improvement (68 vs 71, P=0.008). The median central retinal thickness decreased by 94 µm in the PRN (P=0.002) and by 148 µm in the fixed regimen group (P≤0.001). Complete IRF/SRF reabsorption was found in 58% of eyes in the PRN and in 42% of eyes in the fixed regimen group. At 1-year visit, the percentage of eyes with pigment epithelium detachment did not significantly decrease, but a height reduction was recorded in both groups. The median number of IVA was 3.5 in the PRN and 7 in the fixed regimen group.ConclusionThe switch to aflibercept with both treatment strategies enabled improvement in morphological parameters and stabilization of visual acuity. BCVA improvement and reduction in vision loss with reduction in retinal thickness, fluid and PED height was achieved with the fixed regimen in previously treated nAMD after 1 year.

Indocyanine green enhanced subthreshold diode-laser micropulse photocoagulation treatment of chronic central serous chorioretinopathy.

PURPOSE: To assess the efficacy and safety of indocyanine green (ICG) dye-enhanced subthreshold diode-laser micropulse (SDM) photocoagulation in patients with chronic central serous chorioretinopathy (CCSC) with no spontaneous resolution 6 months after the onset of the disease. STUDY DESIGN: Interventional prospective non-comparative case series of seven patients presenting with CCSC with well-defined active leaking sites (ALS) suitable for laser treatment and with serous neuroepithelial detachment persisting for 6 or more months. METHODS: SDM treatment was performed 15 minutes after the injection of 25 mg of ICG in 2 cc of 5% glucose solution. ALS were treated with a series of 50 500-ms exposures separated by 500-ms pauses. Each 500-ms exposure delivered a train of 250 micropulses at 10% duty cycle and 500 mW power. ICG angiographic images were taken after the treatment without new ICG injection, to check for the presence of laser-induced spots of background hypofluorescence at the treated leakage sites. RESULTS: Within 7-14 days after treatment, all the patients showed improved visual acuity and reduction of serous neuroepithelial detachment on OCT. No signs of laser lesions were visible at fundus examination and on fluorescein angiography. In a period ranging from 4 to 8 weeks, the neuroepithelial detachment was completely resolved in five patients and reduced in two patients. At the 12-month follow-up visits, no recurrence had occurred in the patients, with resolution of the serous neuro-epithelial detachment, and no worsening of the serous detachment or of VA was noted in the patients with incomplete recovery. CONCLUSIONS: These preliminary results suggest that ICG dye-enhanced SMD photocoagulation appears to be an effective treatment, and can represent a viable approach for the management of CSCC with persistent serous neuroepithelial detachment. Post-treatment ICG angiography, without new ICG dye injection, can be used to verify the placement of the SDM laser applications.

Neuroprotection: VEGF, IL-6, and clusterin: the dark side of the moon.

Growth factors and their respective receptors are key regulators in development and homeostasis of the nervous system, and changes in the function, expression, or downstream signaling of growth factors are involved in many neuropathological disorders. Recently, research has yielded a rich harvest of information about molecules and gene, and currently the assumption "a gene-a protein", where each gene encodes the structure of a single protein, is becoming a paradox. In the past years, the discovery of synergic or antagonistic proteins deriving from the same gene is a novelty upsetting. In some way, the conventional function of proteins involved in DNA repair, cell death/growth induction, vascularization, and metabolism is inhibited or shifted toward other pathways by soluble mediators that orchestrate such change depending on the microenvironment conditions. In this chapter, we focus on the antithetic properties that proteins could exert, depending on the microenvironment that orchestrates the complex networks among proteins and their respective partners.

Argon laser trabeculoplasty in triamcinolone acetonide induced ocular hypertension refractory to maximal medical treatment.

PURPOSE: To report two cases of intraocular hypertension after intravitreal injection of triamcinolone acetonide (iTAA) that were refractory to maximal medical therapy and were successfully treated with argon laser trabeculoplasty (ALT). METHODS: Two patients with history of primary open angle glaucoma were treated with intravitreal injection of triamcinolone acetonide for chronic macular edema secondary to branch retinal vein occlusion. Both patients (Case 1 after 2 months and Case 2 after 5 days) developed intraocular hypertension that did not respond to maximal medical therapy. Despite medical therapy, intraocular pressure (IOP) was 45 mmHg in Case 1 and between 34 and 37 mmHg in Case 2. ALT was performed in the inferior 180 degrees angle using the following parameters: 50 microm size, 700 mW, 0.50 sec, 100 spots. RESULTS: In both patients IOP returned to normal level a few days after ALT. CONCLUSIONS: ALT seems to be effective at reducing IOP in patients with intraocular hypertension secondary to iTAA that does not respond to maximal medical treatment.

Indocyanine green dye-enhanced micropulsed diode laser: a novel approach to subthreshold RPE treatment in a case of central serous chorioretinopathy.

PURPOSE: To present a case of central serous chorioretinopathy (CSC) treated with indocyanine green (ICG) dye-enhanced subthreshold micropulsed diode laser photocoagulation. METHODS CASE REPORT: A 35-year-old man presenting with recurrent CSC with persistent serous detachment of the sensory retina in his left eye who declined treatment with a 532 nm laser. Subthreshold treatment, with no visible endpoint, was performed with an 810 nm diode laser 15 minutes after the injection of 25 mg ICG in 2 cc of 5% glucose solution. The laser energy was delivered over the active leakage sites with a sequence of repeated 500 ms "envelopes" each containing a train of 250 micropulses with 500 mW peak power at 10% duty cycle (200 micros ON and 1,800 micros OFF) and each separated by 500 ms intra-envelopes relaxation time. Due to the absence of visible laser-induced lesions, post treatment ICG digital angiographic images were taken without further dye injection to verify that the hypofluorescent spots resulting from the subthreshold laser applications coincided with the points of leakage. RESULTS: After 7 days, the patient presented with a less hyperopic refraction, improved visual acuity, and reduction of serous neuroepithelial detachment. No signs of laser treatment were visible at fluorescein angiography. After 8 weeks, the serous neuroepithelial detachment was almost completely resolved. CONCLUSIONS: ICG dye-enhanced subthreshold micropulsed diode laser photocoagulation appears to be a safe and effective treatment and represents a possible approach for the management of chronic CSC with persistent central serous neuroepithelial detachment. Immediate post treatment ICG angiography, without ICG reinjection, allows documenting the actual number and location of the delivered subthreshold laser applications.