Giuseppe Acri

Nd:YAG laser-induced pitting is a common complication of posterior capsulotomy, yet its effect on light propagation through intraocular lenses (IOLs) remains poorly understood. This exploratory, proof-of-concept experimental study evaluated the impact of Nd:YAG laser exposure on two hydrophobic acrylic IOL models by investigating both morphological damage and its optical consequences. Sixteen hydrophobic acrylic IOLs (eight CT LUCIA 621P, Carl Zeiss Meditec, and eight AcrySof IQ SN60WF, Alcon Laboratories), all with a power of +19.0 D, were mounted on a custom-designed holder; for each model, two lenses served as untreated controls and two lenses were exposed to 5, 10, or 15 standardized Nd:YAG laser applications (1.2 mJ per pulse). Laser-induced surface alterations were assessed using scanning electron microscopy (SEM), while changes in light propagation were analyzed by transmitting a low-power laser beam through each IOL onto a projection screen, acquiring the projected spot with a thermal imaging camera, and computing the intensity-weighted centroid of the spot in MATLAB. Nd:YAG laser exposure produced detectable surface damage in both IOL models, even after only five laser impacts. These structural alterations were associated with a measurable displacement of the transmitted beam centroid (Δpixel) in all treated lenses (mean values 11.1–11.8 pixels for CT LUCIA 621P and 12.4–19.2 pixels for AcrySof IQ SN60WF). Owing to the very small number of replicates (two lenses per condition), the different patterns observed in the two models should be regarded as exploratory trends rather than as evidence of material-dependent behavior. These findings suggest that inadvertent Nd:YAG laser-induced pitting can modify light propagation through the lens and highlight the importance of accurate posterior focusing and the use of the lowest effective laser energy during capsulotomy. To our knowledge, this is the first study to quantify laser-induced beam deviation after Nd:YAG pitting using thermographic centroid analysis. Further studies with larger samples, integrating optical bench measurements such as the modulation transfer function (MTF), point spread function (PSF), and wavefront analysis, are warranted to validate and extend these preliminary findings.

Nd laser posterior capsulotomy is the standard treatment for posterior capsule opacification following cataract surgery. Although generally considered safe, inadvertent laser impacts on the intraocular lens (IOL) optic may induce permanent surface defects that contribute to postoperative dysphotopsias and reduced visual quality. This experimental study investigated the optical consequences of Nd laser-induced damage on two commercially available hydrophobic acrylic IOLs, focusing on retinal light distribution and optical image quality. Two hydrophobic acrylic monofocal IOL models, the CT LUCIA (Carl Zeiss Meditec) and the AcrySof IQ (Alcon), were mounted on a customized experimental holder and exposed to standardized Nd laser applications consisting of 5, 10, or 15 laser shots. Laser interactions were documented using the PhysioGo.Lite laser platform combined with infrared thermal imaging. Untreated IOLs served as controls. Optical performance was subsequently evaluated using a standardized optical bench according to ISO recommendations. Point spread function (PSF) and modulation transfer function (MTF) analyses were performed to quantify retinal image quality, light scattering, and optical degradation. Retinal light distribution was assessed using a high-resolution projection screen simulating the retinal image. Laser exposure produced permanent focal defects on the anterior optical surface of both IOL models, resulting in measurable optical degradation. Even the lowest laser exposure (five shots) generated detectable alterations in light propagation, characterized by increased peripheral light scattering, enlargement of the PSF halo, reduced central peak intensity, and irregular light distribution across the simulated retinal plane. Descriptively, increasing numbers of laser impacts were associated with more pronounced optical disturbances, particularly in the AcrySof IQ samples. MTF analysis demonstrated a reduction in optical performance across multiple spatial frequencies, indicating deterioration of image contrast and resolving power. Although both hydrophobic acrylic IOL models exhibited optical alterations after laser exposure, descriptive differences in the magnitude and distribution of light scatter suggested a possible influence of material composition, refractive index, and surface microarchitecture. These observations should be considered preliminary because of the limited sample size and absence of inferential statistical analysis. Under the present experimental conditions, Nd:YAG laser-induced pitting was associated with measurable structural and optical alterations in two hydrophobic acrylic IOL models. Surface defects alter retinal light distribution, increase forward light scatter, and reduce optical quality, providing a possible optical mechanism that may contribute to postoperative dysphotopsias, although clinical visual symptoms were not directly evaluated in this study. These findings highlight the importance of meticulous laser focusing on the posterior capsule to minimize inadvertent IOL damage and preserve postoperative visual quality. Further investigations combining optical bench analyses with patient-reported visual outcomes are warranted to better define the clinical significance of laser-induced IOL pitting.

Dentin-derived biomaterials are hierarchical collagen–mineral composites increasingly used as bio-based scaffolds for bone regeneration. However, the effect of prolonged storage of extracted teeth on their physicochemical integrity remains unclear. This study evaluated the stability of dentin-derived biomaterials following long-term refrigerated storage (up to six years) using Raman spectroscopy. Extracted human teeth were processed using three preparation systems (BonMaker, Tooth Transformer, and Smart Dentin Grinder), and Raman-derived indices describing mineral and collagen structure were compared with freshly extracted controls. No time-dependent changes were observed in mineral crystallinity, carbonate substitution, or collagen-related parameters, indicating preservation of the collagen–mineral interface during storage. In contrast, the observed differences were primarily associated with processing pathways. Tooth Transformer and Smart Dentin Grinder exhibited Raman profiles closely resembling native dentin, whereas BonMaker showed reduced mineral content and altered mineral–matrix balance consistent with its demineralization protocol. These findings demonstrate that dentin behaves as a structurally stable hierarchical composite, reflecting intrinsic structural organization that limits physicochemical degradation over time. Long-term storage does not compromise dentin integrity, supporting its use as a reliable source of biomaterial for regenerative applications and future tooth banking strategies.

Objective: The technology employed in magnetic resonance imaging (MRI) systems has evolved continuously, resulting in MRI scanners with stronger static magnetic fields (SMF) B0, faster and stronger gradient magnetic fields, and more powerful radiofrequency transmission coils. The most well-known hazard associated with an MRI environment is the projectile effect due to Spatial Field Gradient (SFG). Furthermore, movement through the SFG generates a time-varying magnetic field, which in turn induces a voltage in body tissues. This has the potential to result in a range of physiological symptoms, including headache, nausea, vertigo, phosphenes, numbness, tingling, loss of proprioception, and balance disturbances.Approach: The methodology outlined in this study provides a comprehensive and reliable approach to creating a 3D map of the SMF (fringe field) around a clinical MRI facility. The methodology involves measuring the unperturbed B field, including magnitude and axial components, in specific points and subsequently performing a mathematical procedure involving fitting and interpolation.Main results: Fringe field magnitude and axial components 3D maps are presented for a 3T whole-body MRI scanner for clinical application located in a hospital facility.Significance: The map obtained could be used for a number of purposes, including the evaluation of hazard. This could be achieved by using digital tools to create a simulation of all types of MRI workers movements within the facility. The map could also be used for the training and education of MRI operators, with a view to establishing best practices. The estimation of magnetic field axial components represents a valuable enhancement, as these data can be used to calculate induced electric fields during rotational movements, such as those of the head or torso.

This research proposed a feasibility study for a qualitative and semiquantitative analysis of sheep serum using Raman Spectroscopy analysis as an alternative to standard methodologies. Raman Spectroscopy was used to obtain information about molecular vibrations that can provide information about the behavior of specific variations in the protein network. This study was conducted during the traditional vernal shearing procedure in Sicilian sheep breeding. Twenty female sheep were randomly chosen from a one-hundred Comisana-bred flock habituated to the handling required for shearing and venipuncture. Animals had a mean body weight of 52.35 ± 4.55 kg, were aged between 2 and 3 years old, and were clinically healthy with no evidence of disease and free from internal and external parasites. All animals were shorn on the same day by hand using traditional shearing scissors in a 15 m × 10 m pen. The animals were released into an adjacent pen at the end of the shearing procedure. For each animal, blood samples were collected through jugular venipuncture into a vacutainer tube with a clot activator (Terumo Corporation, Japan) immediately before and 5 and 60 min after the end of the shearing procedure. On the obtained sera, ELISA and Raman spectroscopy analyses were performed to evaluate cortisol concentrations. The band area corresponding to the cortisol vibration mode was identified in the 1300–1366 cm⁻¹ band. The Raman spectra obtained during the various protocol data points showed the same trend, with differences in the intensity of the band area 1300–1366 cm⁻¹. A positive correlation was found between ELISA and Raman assessment in all experimental conditions. The obtained results demonstrate that Raman spectroscopy analysis could be a suitable tool for biomolecule identification. This study demonstrated that this technique provides useful information for understanding sheep responses to stress induced by management conditions.

Objective. The technology employed in magnetic resonance imaging (MRI) systems has evolved continuously, resulting in MRI scanners with stronger static magnetic fields (SMF) B0, faster and stronger gradient magnetic fields, and more powerful radiofrequency transmission coils. The most well-known hazard associated with an MRI environment is the projectile effect due to Spatial Field Gradient (SFG). Furthermore, movement through the SFG generates a time-varying magnetic field, which in turn induces a voltage in body tissues. This has the potential to result in a range of physiological symptoms, including headache, nausea, vertigo, phosphenes, numbness, tingling, loss of proprioception, and balance disturbances. Approach. The methodology outlined in this study provides a comprehensive and reliable approach to creating a 3D map of the SMF (fringe field) around a clinical MRI facility. The methodology involves measuring the unperturbed B field, including magnitude and axial components, in specific points and subsequently performing a mathematical procedure involving fitting and interpolation. Main results. Fringe field magnitude and axial components 3D maps are presented for a 3T whole-body MRI scanner for clinical application located in a hospital facility. Significance. The map obtained could be used for a number of purposes, including the evaluation of hazard. This could be achieved by using digital tools to create a simulation of all types of MRI workers movements within the facility. The map could also be used for the training and education of MRI operators, with a view to establishing best practices. The estimation of magnetic field axial components represents a valuable enhancement, as these data can be used to calculate induced electric fields during rotational movements, such as those of the head or torso.

Magnetic resonance imaging (MRI) scanners have advanced significantly, with a growing use of highfield 3 T systems. This evolution gives rise to safety concerns for healthcare personnel working in proximity to MRI equipment. While manufacturers provide theoretical Gauss line projections, these are typically derived under ideal open-environment conditions and may not reflect real-world installations. For this reason, identical MRI models can produce markedly different fringe field distributions depending on shielding and room configurations. The present study proposes an experimental methodology for the mapping of the fringe magnetic field in the vicinity of three 3 T MRI scanners. Field measurements were interpolated to generate threedimensional magnetic field maps. A comparative analysis was conducted, which revealed notable differences among the scanners. These differences serve to highlight the influence of site-specific factors on magnetic field propagation.

Magnetic Resonance (MR) technology is extensively used in academic and industrial research laboratories and represents one of the most significant methodologies in clinical radiology. Although MR does not use ionizing radiation, it cannot be considered risk-free due to the strong static magnetic fields and time-varying electromagnetic fields employed in the technology. To mitigate risks for MR operators, the European Community and ICNIRP have established safety limits based on the existing literature, primarily related to diagnostic MR. However, the literature on occupational exposure in non-clinical nuclear magnetic resonance (NMR) spectroscopy is limited. Due to their specificity, non-medical NMR environments present unique challenges from the point of view of operator exposure. NMR spectrometers are characterized by extremely high static magnetic fields, reaching up to 28 T in commercial systems; moreover, routine activities performed near the magnet, where field gradients are highest, increase operator exposure. Such environments are not typically perceived as hazardous and are frequented by various types of personnel, often without specific training. This study aims to highlight the critical issues in managing a preclinical MR laboratory equipped with a high-field NMR spectrometer, discussing operator safety challenges and presenting risk assessment data.

Objectives: The aim of this study was to identify the neural pattern activation during mirror therapy (MT) and explore any cortical reorganization and reducing asymmetry of hemispheric activity for upper limb rehabilitation in post-stroke patients. Methods: A box containing a mirror was placed between the arms of the patients to create the illusion of normal motion in the affected limb by reflecting the image of the unaffected limb in motion. We measured the cerebral hemodynamic response using near-infrared spectroscopy (NIRS). We enrolled ten right-handed stroke patients. They observed healthy hand movements in the mirror (MT condition) while performing various tasks (MT condition), and then repeated the same tasks with the mirror covered (N-MT condition). Results: Significant activation of some brain areas was observed in the right and left hemiparesis groups for the MT condition, while lower levels of activation were observed for the N-MT condition. The results showed significant differences in hemodynamic response based on oxygenated (HbO) concentrations between MT and N-MT conditions across all tasks in sensorimotor areas. These neural circuits were activated despite the motor areas being affected by the brain injury, indicating that the reflection of movement in the mirror helped to activate them. Conclusions: These results suggest that MT promotes cortical activations of sensory motor areas in affected and non-affected brain sides in subacute post-stroke patients, and it encourages the use of these tools in clinical practice.

Exposure to 2.45 GHz electromagnetic radiation (EMR) emitted from commonly used devices has been reported to induce oxidative stress in several experimental models. Our study aims to evaluate the efficacy of sulforaphane, a well-known natural product, in preventing radiation-induced toxic effects caused by a 24 h exposure of SH-SY5Y neuronal-like cells and peripheral blood mononuclear cells (PBMCs) to 2.45 GHz EMR. Cells were exposed to radiation for 24 h in the presence or absence of sulforaphane at different concentrations (5–10–25 µg/mL). Cell viability, mitochondrial activity alterations, the transcription and protein levels of redox markers, and apoptosis-related genes were investigated. Our data showed a reduction in cell viability of both neuronal-like cells and PBMCs caused by EMR exposure and a protective effect of 5 µg/mL sulforaphane. The lowest sulforaphane concentration decreased ROS production and increased the Mitochondrial Transmembrane Potential (Δψm) and the NAD+/NADH ratio, which were altered by radiation exposure. Sulforaphane at higher concentrations displayed harmful effects. The hormetic behavior of sulforaphane was also evident after evaluating the expression of genes coding for Nrf2, SOD2, and changes in apoptosis markers. Our study underlined the vulnerability of neuronal-like cells to mitochondrial dysfunction and oxidative stress and the possibility of mitigating these effects by supplementation with sulforaphane. To our knowledge, there are no previous studies about the effects of SFN on these cells when exposed to 2.45 GHz electromagnetic radiation.