Dynamic Coherence Research Articles

Developmental Imaging of Radish Sprouts Using Dynamic Optical Coherence Tomography.

The germination process of radish sprouts was investigated in detail using volumetric dynamic optical coherence tomography (OCT). Dynamic OCT involves the sequential acquisition of 16 OCT images and subsequent temporal variance analysis of each pixel, enabling non-invasive visualization of the cellular and tissue activities of plants. The radish sprouts were longitudinally investigated for up to 12 days, and changes in morphology and dynamic OCT image patterns were observed as the plants developed. The dynamic OCT signals in the vessels and growing roots were relatively high in the early stage of germination and decreased as the tissue matured. These results suggest that dynamic OCT is sensitive to water and nutrient transport as well as cellular activities associated with plant growth.

Analysis of natural and man-made factors of landslide development in the Carpathian region using GIS

Purpose. Determination of the dependencies of spatial relationships between landslides in the Carpathian region of Ukraine and the factors causing them, taking into account the differences in geomorphological, geological, climatic conditions and natural and geographical zoning according to the landscape principle. Methodology. The morphometric analysis of the territory was carried out using QGIS tools to determine the slope angles and exposure; linear characteristics were calculated: distances to the river, road, and houses. Based on the image interpretation data, we calculated the total annual rainfall and average annual air temperature. The impact of the factors considered on landslide formation was assessed using multivariate statistical analysis: factor analysis and linear multiple regression. Findings. Studies on the impact of natural and topographical conditions and anthropogenic activity on the development of landslide processes have been conducted. Orographic and climatic factors play the most important role. Construction of business facilities results in a decrease in the slope stability in 14–19 % of cases. The analysed independed factors showed good consistency between the distribution of existing landslides and the parameters under consideration: the share of the total variance of the factors under consideration is 71–76 %, the coefficient of determination of the regression model is 0.7. Based on the results of geoinformation and statistical analyses, it is proved that differences in geomorphological conditions and human activity (construction of roads, economic facilities) are dominant in the formation of landslides in different landscape zones. Originality. It is established that there is a dynamic coherence between the spatial change in natural conditions and human settlement and activity, which interact with each other to create prerequisites for the development of landslides. Practical value. This study is important from the point of view of understanding and mitigating the cause-and-effect relationship of landslide development for certain territories, and the results obtained can be useful in developing land use planning strategies, infrastructure development, and planning new construction works.

Different Pathways of Skin Aging: Objective Instrumental Evaluation.

Background/Objectives: Hypertrophic and atrophic skin aging represent two distinct phenotypes: hypertrophic aging is marked by deep wrinkles and a leathery texture, whereas atrophic aging is characterized by overall skin thinning, increased vascularity, and a higher risk of non-melanoma skin cancers. This study aims to elucidate the characteristics and differences between hypertrophic and atrophic facial aging subtypes using two non-invasive imaging devices: VISIA® and dynamic optical coherence tomography (D-OCT). Methods: We retrospectively evaluated patients who had presented to the outpatient dermatological clinic at Policlinico Umberto I hospital in Rome, Italy for a non-invasive facial imaging check-up. We included 40 patients aged 60-75 who were imaged with VISIA® and dynamic optical coherence tomography (D-OCT). Based on the number of UV spots and amount of red found on VISIA®, subjects were grouped into four subgroups (PIGM, RED, CONTROL, PIGM + RED), and trends among them were analyzed. Results: We found a strong correlation between VISIA® red area scores and D-OCT vascular density at 300 µm depth, confirming VISIA®'s effectiveness for assessing facial vascularity. Wrinkle count was highest in areas with UV spots, particularly in the PIGM and PIGM + RED groups. Conversely, low attenuation coefficients and dermal density were observed in regions with low UV spots but high red areas. Intermediate subgroups (CONTROL and PIGM + RED) displayed varying parameters. Conclusions: Non-invasive imaging devices are effective in evaluating facial aging and distinguishing between aging subtypes. This study identified two intermediate aging types in addition to the hypertrophic and atrophic subtypes.

Non-destructive viability assessment of cancer cell spheroids using dynamic optical coherence tomography with trypan blue validation

3D cell cultures are widely used in biomedical research for the recapitulation of in vivo microenvironments. Viability assessment and monitoring of these intricate conformations remain an open problem as standard cell viability protocols based on colorimetry or microscopy are not directly applicable to intact 3D samples. Optical coherence tomography (OCT) has been explored extensively for subsurface structural and quasi-functional analysis of 3D cell cultures and tissue. Recent studies of dynamic OCT as a source of cellular contrast have found qualitative associations with necrosis in cell spheroids, suggesting potential as a viability marker. We present empirical and validated evidence for dynamic OCT as a quantitative indicator of cell viability in 3D cultures. We analysed over 240 MCF-7 cancer cell spheroids with dynamic OCT and corresponding viability measurements using the trypan blue exclusion assay. Significant effects of common reagents dimethyl sulfoxide (DMSO) and phosphate-buffered saline (PBS) on OCT readouts were noted. We proposed a regression-based OCT brightness normalisation technique that removed reagent-induced OCT intensity biases and helped improve correspondence to the viability assay. These results offer a quantitative biological foundation for further advances of dynamic OCT as a novel non-invasive modality for 3D culture monitoring.

Structural and Dynamical Quality Assessment of Gap‐Filled Sea Surface Temperature Products

AbstractPrevious studies that intercompared global Level‐4 (L4) sea surface temperature (SST) analyses were centered on the assessment of the accuracy and bias of SST by comparing them with independent near‐surface Argo profile temperature data. This type of assessment is centered on the absolute value of SST rather than on SST spatial properties (gradients), which is more relevant to the study of oceanographic features (e.g., fronts, eddies, etc.) and ocean dynamics. Here, we use, for the first time, the spectrum of singularity exponents to assess the structural and dynamical quality of different L4 gap‐filled products based on the multifractal theory of turbulence. Singularity exponents represent the geometrical projection of the turbulence cascade, and its singular spectrum can be related to the probability density function of the singularity exponents normalized by the scale. Our results reveal that the different schemes used to produce the L4 SST products generate different singularity spectra, which are then used to identify a potential loss of dynamical information or structural coherence. This new diagnostic constitutes a valuable tool to assess the structural quality of SST products and can support data satellite SST producers efforts to improve the interpolation schemes used to generate gap‐filled SST products.

Video Color OCT Angiography for Myopic Choroidal Neovascularization

To investigate the myopic macular neovascularization (mMNV) features on dynamic video-color optical coherence tomography (OCT) angiography (OCTA) and the diagnostic rate versus the static, four-segmentations visualization mode. Retrospective cohort study PARTICIPANTS: Fifty-four patients with mMNV METHODS: Sixty-two eyes with high myopia complicated by mMNV were included. Clinical charts, fluorescein angiography and structural OCT were used as standard reference to assess lesion activity. Static and video-color OCTA were then analysed and compared by two independent reviewers. Morphology description of mMNV on video-color OCTA and differences in the proportion of diagnosis between video-colour and static OCTA. 62 eyes from 54 patients (mean age 63,22 years) were enrolled. Thirty-four (55%) mMNV were active and 28 (45%) inactive. Twenty-two (65%) active mMNV presented on video-color OCTA as an interlacing vascular network in the outer retina and the choriocapillaris. A tapered form was the prevalent size (72,7%). In 3 eyes (9%) an abnormal and irregular vascular network (AVN) was disclosed and in 5 (15%) only some blood flow alteration. All the lesions extended both in the outer retinal and the choriocapillaris. Eleven (39%) inactive mMNV presented on video-color OCTA as an interlacing vascular network too, in the outer retina and the choriocapillaris. Eight (29%) had some AVN and 6 (21%) only some blood flow alteration. The diagnostic rate of video-color vs static OCTA was 95% (IC 95% 86% to 99%) vs 77% (IC 95% 86% to 99%, p= 0.0009), and shows an advantage in favour of video-colour OCTA of 15% (CI 95%, 3%-27%) and 22% (CI 95%, 7%-38%) in active and inactive lesions, respectively (p<0.026). Lesion extension within both the outer retina and the choriocapillaris was present in 90% and 69% of cases on dynamic OCTA and static OCTA, respectively, with a proportion difference of 20% (CI 95%, 10%-31%, p= 0.0005). Concordance between the two examiners was high: 0.95 (95%, CI 0.88 to 1.00) and 0.96 (0.91 to 1.00) for active and inactive lesions, respectively. Video color-enhanced OCTA may help in diagnosing mMNV and should be considered by clinicians in addition to structural OCT and static OCTA.

Benefits of dark chocolate intake on retinal vessels functionality: a randomized, blind, crossover clinical trial

There is a lack of knowledge about the effect of flavanols-rich dark chocolate intake on the anatomy and functionality of retinal vessels. The aim of this study prospective, randomized, blind, crossover clinical trial (ClinicalTrials.gov Identifier: NCT05227248, 07/02/2022) was to evaluate the effect of dark-chocolate intake on the functionality and anatomy of the retinal vessels in healthy subjects using dynamic vessel analyzer (DVA) and optical coherence tomography angiography (OCT-A). Twenty eyes of 20 healthy subjects (mean age, 24.4 ± 1.6 years; 12 females) were enrolled. Participants were randomized to consume 20 g of dark chocolate or 7.5 g of milk chocolate. Visual function, DVA and OCT-A parameters were evaluated before chocolate consumption and two hours later. One week later, the same participants were tested before and after consuming the opposite chocolate. Using OCT-A, no differences were disclosed in terms of perfusion density changes after dark-chocolate and milk-chocolate intake analyzing all chorioretinal plexuses (p > 0.09 in all analyses). Using DVA, a significant increase in the arterial dilation percentage after flicker stimulation was disclosed comparing baseline (2.750 ± 2.054%) with values after the dark chocolate intake (4.145 ± 3.055%, p = 0.016). This difference was not disclosed after the milk chocolate intake (p = 0.465). We disclosed that a reasonable amount of flavanols-rich chocolate in healthy subjects has benefic functional short-term effects in retinal vessels measured with DVA. This suggests a potential role of dark chocolate intake on retinal vessels. Further studies with long-term follow-up are warranted to show if the chronic assumption of dark chocolate could play a favorable role in the prevention of retinal diseases.

Dynamic optical coherence tomography for imaging acute wound healing.

The aim of this study was to investigate acute wound healing with dynamic optical coherence tomography (D-OCT). From 22 patients with 23 split skin graft donor sites, vessels at four wound edges, the wound bed, and adjacent and unaffected skin of the contralateral leg were measured by D-OCT at six time points from surgery to 4 weeks of healing. Changes in vessel orientation, density, diameter, morphology and pattern in horizontal, vertical and 3D images were analysed for wound healing and re-epithelialization. At 300 μm depth, there were significant differences of blobs and serpiginous vessels between normal and wounded skin. The wound had significantly more vertically oriented vessels, a higher degree of branching, vessel density and diameter compared with healthy skin. 3D images showed increased angiogenesis from healthy skin towards the wound centre, significantly higher vessel density at the wound than at normal skin and the highest at the interface. During wound healing blobs, coils and serpiginous vessels occurred significantly more frequently in lesional than healthy skin. Vessel density was greatest at the beginning, decreased and then increased by 4 weeks post-surgery. D-OCT helps to evaluate acute wound healing by visualizing and quantifying blood vessel growth in addition to re-epithelialization.

Dynamic optical coherence tomography unveils subclinical, vascular differences across actinic keratosis grades I-III.

Actinic keratosis (AK) classification relies on clinical characteristics limited to the skin's surface. Incorporating sub-surface evaluation may improve the link between clinical classification and the underlying pathology. We aimed to apply dynamic optical coherence tomography (D-OCT) to characterize microvessels in AK I-III and photodamaged (PD) skin, thereby exploring its utility in enhancing clinical and dermatoscopic AK evaluation. This explorative study assessed AK I-III and PD on face or scalp. AK were graded according to the Olsen scheme before assessment with dermatoscopy and D-OCT. On D-OCT, vessel shapes, -pattern and -direction were qualitatively evaluated at predefined depths, while density and diameter were quantified. D-OCT's ability to differentiate between AK grades was compared with dermatoscopy. Forty-seven patients with AK I-III (n = 207) and PD (n = 87) were included. Qualitative D-OCT evaluation revealed vascular differences between AK grades and PD, particularly at a depth of 300 μm. The arrangement of vessel shapes around follicles differentiated AK II from PD (OR = 4.75, p < 0.001). Vessel patterns varied among AK grades and PD, showing structured patterns in AK I and PD, non-specific in AK II (OR = 2.16,p = 0.03) and mottled in AK III (OR = 29.94, p < 0.001). Vessel direction changed in AK II-III, with central vessel accentuation and radiating vessels appearing most frequently in AK III. Quantified vessel density was higher in AK I-II than PD (p ≤ 0.025), whereas diameter remained constant. D-OCT combined with dermatoscopy enabled precise differentiation of AK III versus AK I (AUC = 0.908) and II (AUC = 0.833). The qualitative and quantitative evaluation of vessels on D-OCT consistently showed increased vascularization and vessel disorganization in AK lesions of higher grades.

Longitudinal tracking of perfluorooctanoic acid exposure on mammary epithelial cell spheroids by dynamic optical coherence tomography.

We investigated the morphology and intracellular motility of mammary epithelial cell (MCF10DCIS.com) spheroids cultured in 3D artificial extracellular matrix under perfluorooctanoic acid (PFOA) exposure. Dynamic optical coherence tomography (OCT) was employed for real-time, non-invasive imaging of these spheroids longitudinally over 12 days under PFOA exposures up to 500 µM. Despite no significant changes in volume or asphericity of spheroids, morphological alterations were observed in OCT images of spheroids at 100 µM on Day 12 and from Day 4 at 500 µM. Intracellular motility was assessed by the inverse-power-law exponent of the speckle fluctuation spectrum (α), and an autocorrelation-based motility amplitude (M). Linear regression indicated that both PFOA concentration and culture time are highly significant predictors for both α and M (p < 0.001 for all). Both PFOA concentration and culture time have positive associations with α and negative association with M, where increased α indicates suppression of higher frequency fluctuations (∼> 2 Hz) relative to those at lower frequencies, and decreased M indicates overall suppression of intracellular motility. This study can lead to the future development of biomarkers for per- and polyfluoroalkyl substances (PFAS) exposure using dynamic OCT and its associated toolkit of quantitative metrics.

A suction blister model to characterize epidermal wound healing and evaluate the efficacy of the topical wound healing agent INM-755 in healthy volunteers.

Non-healing wounds represent a substantial medical burden with few effective treatments available. To address this challenge, we developed a novel epidermal wound healing model using suction blisters in healthy volunteers. This model allowed for the comprehensive assessment of wound healing dynamics and the evaluation of INM-755, a topical cream containing cannabinol, as a potential therapeutic agent. Two clinical studies were conducted: an observational study and an interventional study. In both studies, healthy volunteers underwent a suction blister procedure on their lower back, creating open epidermal wounds. Wound healing parameters were assessed using advanced imaging systems. Skin barrier function and perfusion were evaluated through trans epidermal water loss (TEWL) and dynamic optical coherence tomography (D-OCT), respectively. The observational study demonstrated the successful and reproducible induction of blisters and the removal of epidermal sheet, enabling quantifiable measurements of wound healing parameters over time. Re-epithelialization was observed, revealing recovery of skin barrier function and perfusion. In the interventional study, differences of treatments over time were quantified using the above-described techniques. Despite differences from disease-specific blistering, our developed model provides a valuable platform for studying wound healing mechanisms and assessing novel therapeutic interventions. The sensitivity to treatment effects demonstrated in our study underscores the potential utility of this model in early-phase clinical drug development programs targeting wound healing disorders.

Compressed intracellular motility via non-uniform temporal sampling in dynamic optical coherence tomography.

Optical coherence tomography has great utility for capturing dynamic processes, but such applications are particularly data-intensive. Samples such as biological tissues exhibit temporal features at varying time scales, which makes data reduction challenging. We propose a method for capturing short- and long-term correlations of a sample in a compressed way using non-uniform temporal sampling to reduce scan time and memory overhead. The proposed method separates the relative contributions of white noise, fluctuating features, and stationary features. The method is demonstrated on mammary epithelial cell spheroids in three-dimensional culture for capturing intracellular motility without loss of signal integrity. Results show that the spatial patterns of motility are preserved and that hypothesis tests of spheroids treated with blebbistatin, a motor protein inhibitor, are unchanged with up to eightfold compression. The ability to measure short- and long-term correlations compressively will enable new applications in (3+1)D imaging and high-throughput screening.

Dynamical coherence in isotopy classes of fibered lifted partially hyperbolic diffeomorphisms

Dynamical coherence in isotopy classes of fibered lifted partially hyperbolic diffeomorphisms

Vascular feature identification in actinic keratosis grades I-III using dynamic optical coherence tomography with automated, quantitative analysis

Clinical grading of actinic keratosis (AK) is based on skin surface features, while subclinical alterations are not taken into consideration. Dynamic optical coherence tomography (D-OCT) enables quantification of the skin´s vasculature, potentially helpful to improve the link between clinical and subclinical features. We aimed to compare microvascular characteristics across AK grades using D-OCT with automated vascular analysis. This explorative study examined AK and photodamaged skin (PD) on the face or scalp. AKs were clinically graded according to the Olsen Classification scheme before D-OCT assessment. Using an open-source software tool, the OCT angiographic analyzer (OCTAVA), we quantified vascular network features, including total and mean vessel length, mean vessel diameter, vessel area density (VAD), branchpoint density (BD), and mean tortuosity from enface maximum intensity projection images. Additionally, we performed subregional analyses on selected scans to overcome challenges associated with imaging through hyperkeratosis (each lesion group; n = 18). Our study included 45 patients with a total of 205 AKs; 93 grade I lesions, 65 grade II, 47 grade III and 89 areas with PD skin. We found that all AK grades were more extensively vascularized relative to PD, as shown by greater total vessel length and VAD (p ≤ 0.009). Moreover, AKs displayed a disorganized vascular network, with higher BD in AK I-II (p < 0.001), and mean tortuosity in AK II-III (p ≤ 0.001) than in PD. Vascularization also increased with AK grade, showing significantly greater total vessel length in AK III than AK I (p = 0.029). Microvascular quantification of AK unveiled subclinical, quantitative differences among AK grades I-III and PD skin. D-OCT-based microvascular assessment may serve as a supplement to clinical AK grading, potentially raising perspectives to improve management strategies.

Line-field dynamic optical coherence tomography platform for volumetric assessment of biological tissues.

Dynamic optical coherence tomography (dOCT) utilizes time-dependent signal intensity fluctuations to enhance contrast in OCT images and indirectly probe physiological processes in cells. Majority of the dOCT studies published so far are based on acquisition of 2D images (B-scans or C-scans) by utilizing point-scanning Fourier domain (spectral or swept-source) OCT or full-field OCT respectively, primarily due to limitations in the image acquisition rate. Here we introduce a novel, high-speed spectral domain line-field dOCT (SD-LF-dOCT) system and image acquisition protocols designed for fast, volumetric dOCT imaging of biological tissues. The imaging probe is based on an exchangeable afocal lens pair that enables selection of combinations of transverse resolution (from 1.1 µm to 6.4 µm) and FOV (from 250 × 250 µm2 to 1.4 × 1.4 mm2), suitable for different biomedical applications. The system offers axial resolution of ∼ 1.9 µm in biological tissue, assuming an average refractive index of 1.38. Maximum sensitivity of 90.5 dB is achieved for 3.5 mW optical imaging power at the tissue surface and maximum camera acquisition rate of 2,000 fps. Volumetric dOCT images acquired with the SD-LF-dOCT system from plant tissue (cucumber), animal tissue (mouse liver) and human prostate carcinoma spheroids allow for volumetric visualization of the tissues' cellular and sub-cellular structures and assessment of cellular motility.

Self-reverting vortices in chiral active matter

There is currently a strong interest in the collective behavior of chiral active particles that can propel and rotate themselves. In the presence of alignment interactions for many chiral particles, chiral self-propulsion can induce vortex patterns in the velocity fields. However, these emerging patterns are non-permanent, and do not induce global vorticity. Here we combine theoretical arguments and computer simulations to predict a so-far unknown class of collective behavior. We show that, for chiral active particles, vortices with significant dynamical coherence emerge spontaneously. They originate from the interplay between attraction interactions and chirality in the absence of alignment interactions. Depending on parameters, the vortices can either feature a constant vorticity or a vorticity that oscillates periodically in time, resulting in self-reverting vortices. Our results may guide future experiments to realize customized collective phenomena such as spontaneously rotating gears and patterns with a self-reverting order.

Abstract PO5-07-05: Deep learning can diagnose axillary lymph node metastases on optical virtual histologic images in breast cancer patients during surgery

Abstract Background: Reliable identification of axillary lymph node (ALN) involvement in patients with breast cancer allows for definitive axillary dissection at the time of the initial surgery, thus avoiding the need for a separate axillary surgery. However, conventional intraoperative ALN diagnostic methods are time-consuming and labor-intensive and can result in tissue destruction. Dynamic full field optical coherence tomography, also called dynamic cell imaging (DCI), has been developed and validated to offer rapid and label-free histologic approximations of metastatic and non-metastatic ALNs. In this study, we aim to optimize the diagnostic pipeline with an automated approach and present the results of using a deep learning (DL) algorithm with DCI to predict ALN status intraoperatively in patients with breast cancer. Methods: Breast cancer patients who required ALN staging were enrolled prospectively in this study. DCI was applied to bisected fresh lymph nodes in a non-destructive manner, and the specimens were subsequently sent for histopathological examination, regarded as the gold standard for comparison. A DL model was trained and fine-tuned on over 80,000 DCI images, and the results were mapped to slide level to predict ALN diagnosis. Results: Total 607 DCI slides of ALNs with 112,852 cropped patches were included in the study. The DL model was trained and validated on a dataset containing 481 slides and tested on an independent testing dataset with 126 slides. In the test set, the DL algorithm yielded accuracy for prediction of ALN status, with sensitivity and specificity of 91.9% and 95.5% and an area under the receiver operating characteristic curve (AUC) of 0.937 (95% confidence interval [CI]: 0.912-0.957) at slide level. Conclusion: These results demonstrate that the integration of DCI with DL is rapid, reduces labor requirements and minimizes tissue destruction. Meanwhile, this algorithm had high classification accuracy to predict the metastatic burden of ALNs for patients with breast cancer. Citation Format: Shuwei Zhang, Houpu Yang, Jin Zhao, Shu Wang. Deep learning can diagnose axillary lymph node metastases on optical virtual histologic images in breast cancer patients during surgery [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-07-05.

Quantum G-coherence factorization law under fully and strictly incoherent operations

Quantum coherence plays an important role in quantum resource theory, which is strongly related with entanglement. In order to quantify the full coherence of qudit states, we define G-coherence and convex roof of G-coherence, and prove that the G-coherence is a strong coherence monotone and the convex roof of G-coherence is a coherence measure under fully and strictly incoherent operation (FSIO), respectively. Similar to the entanglement factorization law, we prove a coherence factorization law for arbitrary d-dimensional quantum pure and mixed states under FSIO channels, which generalizes the entanglement factorization law for bipartite pure states. Our results will play an important role in the simplification of dynamical coherence measure.

Neural-network based high-speed volumetric dynamic optical coherence tomography

We demonstrate deep-learning neural network (NN)-based dynamic optical coherence tomography (DOCT), which generates high-quality logarithmic-intensity-variance (LIV) DOCT images from only four OCT frames. The NN model is trained for tumor spheroid samples using a customized loss function: the weighted mean absolute error. This loss function enables highly accurate LIV image generation. The fidelity of the generated LIV images to the ground truth LIV images generated using 32 OCT frames is examined via subjective image observation and statistical analysis of image-based metrics. Fast volumetric DOCT imaging with an acquisition time of 6.55 s/volume is demonstrated using this NN-based method.

Tirbanibulin 1% Ointment Effectiveness for Actinic Keratosis Treatment Evaluated by Dynamic Optical Coherence Tomography

Background. Actinic keratosis (AK) is a common premalignant skin condition. Its diagnosis is based on a clinical and sometimes dermoscopic examination, but, in some situations, a skin biopsy may be necessary. Dynamic optical coherence tomography (D-OCT) can often bypass this need, by noninvasive evaluation of skin morphology. Early and effective treatment of AKs is important to prevent the progression to invasive squamous cell carcinoma (iSCC). Tirbanibulin 1% ointment, a new topical field therapy for AKs, has recently been introduced. Objectives. The aim of this study was to evaluate the efficacy and safety of tirbanibulin 1% ointment for the field treatment of nonhyperkeratotic, nonhypertrophic AKs (Olsen grade 1) on the face and/or scalp in adults, using D-OCT technology. Methods. Patients, presenting multiple, mild to moderate AKs on the face and scalp, in treatment with tirbanibulin 1% ointment for five consecutive days of an area measuring 25 cm2, were evaluated with videodermoscopy (V-track Vidix 4.0) and D-OCT (VivoSight Dx, Michelson Diagnostics Ltd., Kent, England, United Kingdom), as normal clinical practice. The lesions were staged according to the Olsen classification, excluding the most aggressive lesions. Results. We retrospectively evaluated 50 patients (27 males and 23 females, mean age 76 ± 7.9 years). At 57 days posttreatment, the complete clearance rate was 68% (n = 34) and partial clearance rate was 76% (n = 38). D-OCT showed markedly improved morphology, including a better recognizable dermal-epidermal junction (DEJ), associated with reduced inflammation. The most common adverse events reported were erythema and scaling, which were mostly mild and self-limiting. Conclusions. This study demonstrated that tirbanibulin may be considered an effective and well-tolerated treatment option for nonhyperkeratotic, nonhypertrophic AKs. It showed a favorable safety profile, with mostly mild adverse events. D-OCT can be considered a useful tool for personalizing AK treatment and monitoring.