Comparison of central corneal thickness measured by automatic and manual analysis of optical coherence tomography.

PURPOSE: To compare central corneal thickness (CCT) measured with optical coherence tomography (OCT) using an automatic algorithm (A-OCT) vs. manual measurements (M-OCT) with respect to the gold standard ultrasound pachymetry (USP). METHODS: CCT measurements were performed on both eyes of 28 healthy subjects at four times of the day. A-OCT used an automatic software analysis of the corneal image, M-OCT was performed by two operators by setting a digital calliper on the corneal borders, and USP was performed after corneal anesthesia. Measurements were compared using a three-way repeated measures ANOVA. Bland-Altman plots were used to evaluate the agreement between OCT measurements and USP. RESULTS: Both A-OCT and M-OCT significantly underestimated the USP measures, with the mean difference, i.e., the systematic error, being larger for A-OCT (- 19.0 µm) than for M-OCT (- 6.5 µm). Good reproducibility between the two operators was observed. Bland-Altman plots showed that both OCT methods suffered from proportional errors, which were not affected by time and eye. CONCLUSIONS: Measuring CCT with OCT yielded lower values than USP. Therefore, clinicians should be aware that corneal thickness values may be influenced by the measurement method and that the various devices should not be used interchangeably in following up a given patient. Intriguingly, M-OCT had less systematic error than A-OCT, an important outcome that clinicians should consider when deciding to use an OCT device.

Early morpho-functional changes in patients treated with hydroxychloroquine: a prospective cohort study.

PURPOSE: We aimed to find earlier morphological and functional alterations in the retinas of patients treated with hydroxychloroquine (HCQ). This was a prospective cohort study. METHODS: We examined 33 patients (mean age, 57.14 [SD, 11.02] years) who were affected by various types of rheumatic diseases. The mean treatment period was 124.7 [SD, 99.4] months, and the mean total drug intake was 5.41 [SD, 3.34] g daily at baseline. The control group consisted of 28 subjects with a mean age of 61.25 [SD, 2.16 years]. The set of tests encompassed best-corrected visual acuity (BCVA), a multifocal electroretinogram (mfERG), spectral-domain optical coherence tomography (SD-OCT), fundus auto fluorescence (FAF), the 10-2 automated visual field (VF) test (10-2 VF), and frequency-doubling technology (FDT). RESULTS: The mfERG P1 wave density amplitudes decreased in all the rings, from 31.10 to 28.02 (p = 0.008) in the first ring, and from 18.29 to 16.55 [p < 0.001], from 12.050 to 10.91 [p = 0.002], from 9.53 to 8.69 [p = 0.003], and from 8.25 to 7.48 [p = 0.001] nanovolts/degree2 in rings 2, 3, 4, and 5, respectively. A significant reduction was found also in the N1 wave in the second ring. The SD-OCT retinal thickness measurement revealed significant thinning in five sectors, including the outer and inner nasal sectors, the outer and inner temporal sectors, and the inner superior sector. The 10-2 VF mean deviation paradoxically improved, while minimal FAF alterations in the retinal pigment epithelium were found in eight eyes. CONCLUSIONS: mfERGs and SD-OCT were altered in our patients before significant retinal changes occurred.

Direct current stimulation modulates the excitability of the sensory and motor fibres in the human posterior tibial nerve, with a long-lasting effect on the H-reflex.

Several studies demonstrated that transcutaneous direct current stimulation (DCS) may modulate central nervous system excitability. However, much less is known about how DC affects peripheral nerve fibres. We investigated the action of DCS on motor and sensory fibres of the human posterior tibial nerve, with supplementary analysis in acute experiments on rats. In forty human subjects, electric pulses at the popliteal fossa were used to elicit either M-waves or H-reflexes in the Soleus, before (15 min), during (10 min) and after (30 min) DCS. Cathodal or anodal current (2 mA) was applied to the same nerve. Cathodal DCS significantly increased the H-reflex amplitude; the post-polarization effect lasted up to ~ 25 min after the termination of DCS. Anodal DCS instead significantly decreased the reflex amplitude for up to ~ 5 min after DCS end. DCS effects on M-wave showed the same polarity dependence but with considerably shorter after-effects, which never exceeded 5 min. DCS changed the excitability of both motor and sensory fibres. These effects and especially the long-lasting modulation of the H-reflex suggest a possible rehabilitative application of DCS that could be applied either to compensate an altered peripheral excitability or to modulate the afferent transmission to spinal and supraspinal structures. In animal experiments, DCS was applied, under anaesthesia, to either the exposed peroneus nerve or its Dorsal Root, and its effects closely resembled those found in human subjects. They validate therefore the use of the animal models for future investigations on the DCS mechanisms.

Anticipatory Postural Adjustments associated with reaching movements are programmed according to the availability of visual information.

During goal-directed arm movements, the eyes, head, and arm are coordinated to look at and reach the target. We examined whether the expectancy of visual information about the target modifies Anticipatory Postural Adjustments (APAs). Ten standing subjects had to (1) move the eyes, head and arm, so as to reach, with both gaze and index-finger, a target of known position placed outside their visual field (Gaze-Reach); (2) look at the target while reaching it (Reach in Full Vision); (3) keep the gaze away until having touched it (Reach then Gaze) and (4) just Gaze without Reach the target. We recorded eye, head, right arm, and acromion kinematics, EMGs from upper- and lower-limb muscles, and forces exerted on the ground. In Gaze-Reach, two coordination strategies were found: when gaze preceded arm muscle recruitment (Gaze-first) and when the opposite occurred (Reach-first). APAs in acromion kinematics, leg muscles, and ground forces started significantly earlier in Gaze-first vs. Reach-first (mean time advance: 44.3 ± 8.9 ms), as it was in Reach in Full Vision vs. Reach then Gaze (39.5 ± 7.9 ms). The Gaze-first to Reach-first time-shift was similar to that between Reach in Full Vision and Reach then Gaze (p = 0.58). Moreover, Gaze without Reach data witnessed that the head-induced postural actions did not affect the APA onset in Gaze-first and Reach-first. In conclusion, in Gaze-first, the central control of posture considers visual information while planning the movement, like in Reach in Full Vision; while Reach-first is more similar to Reach then Gaze, where vision is not required.

Intended rather than actual movement velocity determines the latency of anticipatory postural adjustments.

The literature reports that anticipatory postural adjustments (APAs) are programmed according to movement velocity. However, the linkage between APAs and velocity has been highlighted within single subjects who were asked to voluntarily change movement velocity; therefore, till now, it has been impossible to discern whether the key factor determining APA latency was the intended movement velocity or the actual one. Aim of this study was to distinguish between these two factors. We analyzed the APA chain that stabilizes the arm during a brisk index finger flexion in two groups of subjects: (1) 29 who composed our database from previous experiments and were asked to "go-as-fast-as-possible" (go-fast), but actually performed the movement with different speeds (238-1, 180°/s), and (2) ten new subjects who performed the go-fast movement at more than 500°/s and were then asked to go-slow at about 50% of their initial velocity, thus moving at 300-800°/s. No correlation between APA latency and actual movement speed was observed when all subjects had to go-fast (p > 0.50), while delayed APAs were found in the ten new subjects when they had to go-slow (p < 0.001). Moreover, in the speed range between 300 and 800°/s, the APA latency depended only on movement instruction: subjects going fast showed earlier APAs than those going slow (p < 0.001). These data suggest a stronger role of the intended movement velocity versus the actual one in modifying the timing of postural muscles recruitment with respect to the prime mover. These results also strengthen the idea of a shared postural and voluntary command within the same motor act.

Temporal disruption of upper-limb anticipatory postural adjustments in cerebellar ataxic patients.

Voluntary movements induce postural perturbations, which are counteracted by anticipatory postural adjustments (APAs) that preserve body equilibrium. Little is known about the neural structures generating APAs, but several studies suggested a role of sensory-motor areas, basal ganglia, supplementary motor area and thalamus. However, the role of the cerebellum still remains an open question. The aim of this present paper is to shed further light on the role of cerebellum in APAs organization. Thus, APAs that stabilize the arm when the index finger is briskly flexed were recorded in 13 ataxic subjects (seven sporadic cases, four dominant ataxia type III and two autosomal recessive), presenting a slowly progressive cerebellar syndrome with four-limb dysmetria, and compared with those obtained in 13 healthy subjects. The pattern of postural activity was similar in the two groups [excitation in triceps and inhibition in biceps and anterior deltoid (AD)], but apparent modifications in timing were observed in all ataxic subjects in which, on average, triceps brachii excitation lagged the onset of the prime mover flexor digitorum superficialis by about 27 ms and biceps and AD inhibition were almost synchronous to it. Instead, in normal subjects, triceps onset was synchronous to the prime mover and biceps and AD anticipated it by about 40 ms. The observed disruption of the intra-limb APA organization confirms that the cerebellum is involved in APA control and, considering cerebellar subjects as a model of dysmetria, also supports the view that a proper APA chain may play a crucial role in refining movement metria.

Ischemic block of the forearm abolishes finger movements but not their associated anticipatory postural adjustments.

Voluntary movement is known to induce postural perturbations that are counteracted by unconscious anticipatory postural adjustments (APAs). Thus, for every movement, two motor commands are dispatched: a voluntary command recruiting the prime mover and a postural command driving the APAs. These commands are classically thought to be separated; this study investigates whether they could be instead considered as two elements within the same motor program. We analyzed the APAs in biceps brachii, triceps brachii and anterior deltoid that stabilize the arm when briskly flexing the index finger (prime mover flexor digitorum superficialis). APAs and prime mover activation were recorded before, under and after ischemic block of the forearm. Ischemia paralyzed the prime mover, thus suppressing the finger movement and the ensuing postural perturbation. If the two commands had been separated, it would have been expected that after a few failed attempts to flex the index finger, the APAs were suppressed too, being purposeless without postural perturbation. APAs were still present under ischemia even after 60 movement trials. No significant changes were found in APA amplitude in biceps and triceps among different conditions, or in the average APA latency. Inhibitory APA in anterior deltoid was reduced but still present under ischemia. In addition, the pharmacologic block of the sole median nerve produced similar effects. APAs were instead almost abolished when applying a fixation point to the wrist. The observation that APAs remained tailored to the expected perturbation even when that perturbation did not occur supports the idea of a functionally unique motor command driving both the prime mover and the muscles of the APA chain.

Hand immobilization affects arm and shoulder postural control.

It is a common experience, immediately after the removal of a cast or a splint, to feel motor awkwardness, which is usually attributed to muscular and joint immobilization. However, the same feeling may also be perceived after a brief period of immobilization. We provide evidence that this last effect stems from changes in the cortical organization of the focal movement as well as in the associated anticipatory postural adjustments. Indeed, these two aspects of the motor act are strongly correlated, although scaled in different manners. In fact, they are both shaped in the primary motor cortex, they both undergo similar amplitude and latency modulation and, as we will show, they are both impaired by the immobilization of the lone prime mover. Neuromuscular effects of limb immobilization are well known; however, most papers focus on changes occurring in the pathways projecting to the prime mover, which acts on the immobilized joint. Conversely, this study investigates the effect of immobilization on anticipatory postural adjustments. Indeed, we show that 12 h of wrist and fingers immobilization effectively modify anticipatory postural adjustments of the elbow and the shoulder, that is, those joints not immobilized within the fixation chain. Accordingly, the motor impairment observed after short-term immobilization most likely stems from the unbalance between anticipatory postural adjustments and the focal movement.

Human recombinant nerve growth factor (Cenegermin) in a patient affected by primary congenital glaucoma with neurotrophic keratopathy.

PURPOSE: To report a case of neurotrophic keratopathy (NK) in a patient affected by primary congenital glaucoma (PCG) who undergone glaucoma drainage implant surgery. NK was successfully treated with human recombinant Nerve Growth Factor (Cenegermin) eye drops. CASE REPORT DESCRIPTION: A 46-years-old patient affected by primary congenital glaucoma underwent Ahmed glaucoma valve implantation in the right eye, after several unsuccessful surgeries to control intraocular pressure (IOP) since the age of three. Surgical intervention was performed without complications, and IOP was well-controlled post-operatively. However, 1 month after surgery, he developed NK with stromal ulceration, initially treated with a topical combination of preservative-free artificial tears and antibiotic ointment. As NK did not resolve, a new treatment with Cenegermin 20 µg/ml eye drops, 6 times daily, was started. OUTCOME: NK completely resolved after 8 weeks of Cenegermin treatment, with complete restoration of corneal integrity and improvement of corneal sensitivity and transparency. Visual acuity in the operated eye reverted to the pre-operative value. CONCLUSION: Cenegermin was extremely effective in restoring corneal integrity in this PCG patient with NK.

Physiology-Enhanced Data Analytics to Evaluate the Effect of Altitude on Intraocular Pressure and Ocular Hemodynamics.

Altitude affects intraocular pressure (IOP); however, the underlying mechanisms involved and its relationship with ocular hemodynamics remain unknown. Herein, a validated mathematical modeling approach was used for a physiology-enhanced (pe-) analysis of the Mont Blanc study (MBS), estimating the effects of altitude on IOP, blood pressure (BP), and retinal hemodynamics. In the MBS, IOP and BP were measured in 33 healthy volunteers at 77 and 3466 m above sea level. Pe-retinal hemodynamics analysis predicted a statistically significant increase (p < 0.001) in the model predicted blood flow and pressure within the retinal vasculature following increases in systemic BP with altitude measured in the MBS. Decreased IOP with altitude led to a non-monotonic behavior of the model predicted retinal vascular resistances, with significant decreases in the resistance of the central retinal artery (p < 0.001) and retinal venules (p = 0.003) and a non-significant increase in the resistance in the central retinal vein (p = 0.253). Pe-aqueous humor analysis showed that a decrease in osmotic pressure difference (OPD) may underlie the difference in IOP measured at different altitudes in the MBS. Our analysis suggests that venules bear the significant portion of the IOP pressure load within the ocular vasculature, and that OPD plays an important role in regulating IOP with changes in altitude.

Efficacy and Safety of PreserFlo® MicroShunt After a Failed Trabeculectomy in Eyes with Primary Open-Angle Glaucoma: A Retrospective Study.

INTRODUCTION: To evaluate the efficacy and safety of PreserFlo® MicroShunt in primary open angle glaucoma (POAG) eyes after a single failed trabeculectomy. METHODS: Retrospective review of POAG eyes with a failed trabeculectomy that underwent PreserFlo® MicroShunt implantation from March 2019 to November 2019, in two Italian glaucoma centers. Pre- and postoperative data were collected and compared. RESULTS: A total of 31 surgeries in 31 patients were reviewed. Mean preoperative IOP and mean preoperative number of medications were 24.12 ± 3.14 mmHg and 3.29 ± 0.64, respectively, and decreased to 12.56 ± 2.64 mmHg and 0.46 ± 0.77 at the 12-month postoperative follow-up visit (p < 0.01). The most frequent adverse events were transient hypotony (6 eyes, 19.3%) and choroidal effusion (3 eyes, 9.6%). In all cases spontaneous resolution was observed, with no intervention. CONCLUSION: In POAG eyes with a single failed trabeculectomy, the PreserFlo® MicroShunt was safe and effective in reducing the IOP after a 12-month follow-up. The PreserFlo® MicroShunt may represent a viable choice as a second surgery.

A Comparison of Hyper-Reflective Retinal Spot Counts in Optical Coherence Tomography Images from Glaucomatous and Healthy Eyes.

PURPOSE: To compare the number of hyper-reflective retinal spots (HRS) in optical coherence tomography (OCT) images of healthy controls and patients affected with primary open angle glaucoma (POAG). METHODS: Thirty patients affected with POAG and 34 healthy controls were recruited and underwent raster OCT examination of the macular region. Among the acquired B-scans, the one with the lowest foveal thickness was selected, and a central area of 3000 µm was defined (region of interest, ROI), in order to identify HRS. HRS were defined as small point-like hyper-reflective elements, detectable at the visual inspection of the OCT image. HRS were independently counted by two investigators in the ROI of each OCT scan. RESULTS: Inter-rater agreement for HRS counting was good to excellent (ICC = 0.96, 95% CI: 0.83-0.99). More HRS were found in the OCT images from glaucoma patients, in comparison with healthy controls (average value: 90.5 ± 13.02 and 74.72 ± 11.35, for glaucoma and healthy subjects, respectively; p < 0.01). Significant correlations between the average number of HRS and visual field mean deviation (MD, p = 0.01) and pattern standard deviation (PSD, p < 0.01) were found. CONCLUSIONS: OCT images from glaucoma patients showed a higher number of HRS when compared with healthy controls. As HRS have been hypothesized to be a sign of neuroinflammation, these results may support the role of neuroinflammation in glaucoma etiopathogenesis.

Pre-operative conjunctival flora in patients with local and/or systemic risk factors for post cataract surgery infection in Northern Italy.

PURPOSE: To investigate the pre-operative conjunctival flora in patients undergoing cataract surgery with major local and/or systemic risk factors for developing post-operative infection. METHODS: A total of 83 patients underwent bacterial culture and sensitivity testing of conjunctival swabs obtained from both eyes because of local risk factors at the pre-operative visit (i.e. chronic blepharitis, conjunctivitis, or lacrimal system disease), and/or systemic risk factors (i.e. autoimmune or skin disorders) for developing post-operative infection. If the swab was found positive, an antimicrobial susceptibility test was performed, and a specific antibiotic therapy was administered. Surgery was performed when a repeat conjunctival swab (after antibiotic treatment) showed negative cultures. RESULTS: Cultures were found positive in 25.3% of patients. Staphylococcus aureus (18%) and Staphylococcus epidermidis (15%) were the most frequently isolated microorganisms. Gram-negative bacteria, including Pseudomonas aeruginosa, were present in nine cases (8%). CONCLUSION: Present results showed a low rate of swab positivity compared to previous published data, and slightly different microbial flora. The differences observed may be caused by geographical factors and/or to the specific characteristics of the subgroup of studied patients. Considering that the surface microbial flora is one of the major causes of endophthalmitis, this information may be useful in selecting antibacterial regimens to prevent serious ocular infections, and restrain the increasing problem of antibiotic resistance.

Glaucoma and neuroinflammation: An overview.

Glaucoma is an optic neuropathy characterized by well-defined optic disc morphological changes (i.e., cup enlargement, neuroretinal border thinning, and notching, papillary vessel modifications) consequent to retinal ganglion cell loss, axonal degeneration, and lamina cribrosa remodeling. These modifications tend to be progressive and are the main cause of functional damage in glaucoma. Despite the latest findings about the pathophysiology of the disease, the exact trigger mechanisms and the mechanism of degeneration of retinal ganglion cells and their axons have not been completely elucidated. Neuroinflammation may play a role in both the development and the progression of the disease as a result of its effects on retinal environment and retinal ganglion cells. We summarize the latest findings about neuroinflammation in glaucoma and examine the connection between risk factors, neuroinflammation, and retinal ganglion cell degeneration.

A Case of Delayed-onset Hemorrhagic Choroidal Detachment After PreserFlo Microshunt Implantation in a Glaucoma Patient Under Anticoagulant Therapy.

PURPOSE: To describe a case of delayed-onset hemorrhagic choroidal detachment (HCD) in a patient affected by primary open-angle glaucoma (POAG) undergone PreserFlo Microshunt implantation. CASE REPORT DESCRIPTION: A 76-year-old patient with POAG, under treatment with Dabigatran (a novel oral anticoagulant), underwent an uncomplicated PreserFlo Microshunt implantation in the left eye. In the first postoperative day, intraocular pressure (IOP) was 6 mm Hg, conjunctival bleb was diffuse, anterior chamber (AC) deep, and device correctly positioned. Twelve days after surgery, the patient had emergency access complaining severe ocular pain and sudden vision loss. Ophthalmological evaluation revealed shallow AC and an IOP of 50 mm Hg. The fundus examination revealed almost kissing HCD. OUTCOME: Immediate topical treatment with atropine, aqueous humor suppressants, and corticosteroids was started. Because of high IOP, ocular pain, and the presence of almost kissing HCD, surgical drainage of suprachoroidal hemorrhage and removal of PreserFlo Microshunt were performed. An improvement of the clinical condition was observed in the following postoperative days, with partial resolution of the HCD and a decrease of the IOP. On the third postoperative day, there was a worsening of the HCD, with a reduction of the AC depth and IOP elevation. HCD was drained through the previously performed sclerotomies, associated with pars-plana vitrectomy and silicone-oil tamponade. HCD completely resolved during the following 6 weeks, with IOP reduction and partial improvement of visual acuity. CONCLUSION: Great attention must be taken in patients with glaucoma under treatment with a novel oral anticoagulant, also when planning PreserFlo Microshunt implantation.

Solitary Free-Floating Iris Cyst Associated With Bilateral Pigment Dispersion Syndrome: Report of a Case.

CASE REPORT: A 27-year-old white man with a 5-year history of pigment dispersion syndrome presented for evaluation. His past ocular history was significant for bilateral intraocular pressure elevation that had required intraocular pressure -lowering medication (beta-blocker-prostaglandin analogue fixed combination). On ophthalmic examination, the visual acuity was 20/20 without correction in both eyes. Anterior chamber slit-lamp examination revealed a pigmented round mass with modest transillumination at 6-o'clock position of the right eye. When asked, the patient reported that he had first noticed a shadow in his right eye during childhood when he was flexing his neck and keeping a face-down position for a few seconds. During a head-flexing test, the mass freely floated in the anterior chamber. When the patient extended the neck, the round mass could be seen in front of the pupil. After a few moments, the mass would slowly fall to the iridocorneal angle at the 6-o'clock position. Ultrasound biomicroscopy and anterior-segment optical coherence tomography confirmed that the lesion was a pigmented cyst without internal reflectivity. Specular microscopy examinations, performed to exclude cyst-induced corneal endothelium compromise, revealed a cell-density of ~3000 cells/mm in both eyes. Gonioscopy showed an open angle with trabecular pigmentation and funduscopy a cup-to-disc ratio of 0.5 bilaterally. Visual fields and optical coherence tomography tests were within normal limits. CONCLUSIONS: The etiology of free-floating iris cysts is unclear, but it is generally agreed that these masses are usually dislodged pigment epithelial cysts. This is the first report of a unilateral free-floating iris cyst associated with bilateral pigment dispersion syndrome.

The Mont Blanc Study: The effect of altitude on intra ocular pressure and central corneal thickness.

The aim of the Mont Blanc Study was to investigate the relationship between intraocular pressure (IOP), central corneal thickness (CCT), and altitude in healthy subjects. Thirty-three eyes of 33 healthy volunteers (mean age: 24.8 years, 17 females) had their IOP measured with Perkins and I-Care tonometers and their CCT using ultrasound pachymetry at three locations in Italy with different altitudes: Pavia, (PV), 77 meters above sea level (a.s.l); Courmayeur (CM), 1300 meters a.s.l; Pointe Helbronner (PH), 3466 meters a.s.l.). The measurements were performed at 9 am, 11 am, 1 pm and 3 pm (±30') in indoor settings (mean temperature of 19°C) in PV and PH. At 9 am, CCT and IOP were measured outdoor (mean temperature of -1.4°C) at PH. The mean values of the IOP curve decreased from PV to PH with the Perkins (p = 0.02) and I-Care tonometers (p = 0.001). Instead, CCT increased upon ascension from PV to PH (p = 0.01), and from CM to PH (p = 0.002). When exposed to sub-zero temperature, the IOP increased (p<0.001), while the CCT did not change (p = 0.30). The results suggest that IOP significantly decreased and CCT significantly increased upon ascension from the sea level to higher altitudes.

Identification of SARS-CoV-2 RNA in the conjunctival swab of an Italian pediatric patient affected with COVID-19: A case report.

INTRODUCTION: To report a case of identification of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) RNA in ocular specimen in a pediatric patient affected with Coronavirus disease 2019 (COVID-19) with no signs of ocular involvement. CASE DESCRIPTION: A 11-year old male patient with confirmed COVID-19 infection was hospitalized at the Pediatric Clinic Clinic of the IRCCS Foundation and Hospital San Matteo, Pavia, Italy. Three days after hospital admission, because of the patient complaining very mild ocular symptoms, an ophthalmological evaluation was performed. No signs related to conjunctivitis or keratitis were found but a conjunctival swab was collected as well, based on patient's medical history. The specific SARS-CoV-2 reverse transcription PCR (RT-PCR) was performed, unearthing the presence of viral RNA from the swab. On day 25 from hospitalization, the conjunctival swab was repeated, giving negative result. CONCLUSIONS: This is the first report of the identification of SARS-CoV-2 RNA in ocular specimen in a pediatric patient without signs of ocular involvement. However, despite the transmission through tears is theoretically possible, it is still unclear whether this could be considered as an important route for the spread of SARS-CoV-2.

Anterior Chamber Angle Assessment Techniques: A Review.

Assessment of the anterior chamber angle (ACA) is an essential part of the ophthalmological examination. It is intrinsically related to the diagnosis and treatment of glaucoma and has a role in its prevention. Although slit-lamp gonioscopy is considered the gold-standard technique for ACA evaluation, its poor reproducibility and the long learning curve are well-known shortcomings. Several new imaging techniques for angle evaluation have been developed in the recent years. However, whether these instruments may replace or not gonioscopy in everyday clinical practice remains unclear. This review summarizes the last findings in ACA evaluation, focusing on new instruments and their application to the clinical practice. Special attention will be given to the comparison between these new techniques and traditional slit-lamp gonioscopy. Whereas ultrasound biomicroscopy and anterior segment optical coherence tomography provide quantitative measurements of the anterior segment's structures, new gonio-photographic systems allow for a qualitative assessment of angle findings, similarly to gonioscopy. Recently developed deep learning algorithms provide an automated classification of angle images, aiding physicians in taking faster and more efficient decisions. Despite new imaging techniques made analysis of the ACA more objective and practical, the ideal method for ACA evaluation has still to be determined.

Screening and Follow-Up of Acute ROP: Reproducibility of Fluorescein Angiography.

INTRODUCTION: Binocular indirect ophthalmoscopy (BIO) is fundamental for screening of retinopathy of prematurity (ROP). Digital retinal imaging devices with fluorescein angiography (FA) proved to be useful in screening and management of ROP. FA provides valuable additional information that is not detectable through ophthalmoscopy. FA images are relatively easy to interpret even by personnel without specific experience in ROP. The aim of this study is to evaluate reproducibility of FA for the screening and follow-up of ROP. METHODS: A total of 106 pairs of FA images of 30 eyes of 15 premature infants with stage II ROP were evaluated by 5 ophthalmologists: 2 experts, 2 non-experts, and 1 expert in reading FA in adult patients. Each operator gave a score to each of following parameters: leakage, ischemic areas, peripheral plus disease and vascular anomalies. The images were reviewed twice. Intra- and inter-concordance between the readers of the FA findings was evaluated by the means of Cohen's kappa coefficient (κ). RESULTS: The intra-operator concordance was very good (κ > 0.81) for all FA findings. Inter-operator concordance was good (κ > 0.41) for all operators and all FA findings. Global concordance was: substantial (intra-inter readers: κ > 0.61) for leakage, ischemic areas, and plus disease; almost perfect (κ > 0.81) for vascular anomalies; and moderate (κ = 0.41-0.60) for continuity/discontinuity of the ischemic areas. Total FA score was directly correlated to the percentage of treatment: a score ≥ 7 was correlated with 100% treatment and a score ≤ 3 with no treatment. Treatment timing was inversely correlated to FA score: a score ≥ 8 was correlated with a timely treatment (≤ 6 days), and a score ≤ 7 was correlated with a delayed treatment (< 10 days). CONCLUSION: This study showed that FA represents a reproducible imaging technique. It is useful for detecting ROP progression, and to define the treatment timing and type.