Optical coherence tomography: a non-invasive technique applied to conservation of paintings

Objectives: Optical coherence tomography (OCT) is a non-invasive technique based on optical imaging with a micrometre resolution. The purpose of this study is to investigate the potential role of OCT in evaluating oral mucosa bullous diseases. Methods: two patients with bullous pemphigoid (BP) and one patient with pemphigus vulgaris (PV) were examined and images of their oral lesions were performed using OCT. Results: In OCT images, the BP blister has a clearly different morphology from the PV one compared to the blistering level. Conclusion: This exploratory study suggests that the OCT is able to distinguish epithelial and subepithelial layer in vivo images of healthy oral mucosa from those with bullous diseases, assisting the clinicians in differential diagnosis.The presented data are in accordance with the scientific literature, although a wider pool of cases is needed to increase statistical power. Histological examination and immunofluorescence methods remain the gold standard for the diagnosis of oral bullous diseases. In this context, the OCT can provide the clinician with a valuable aid both as an additional diagnostic tool and in the follow up of the disease.

Download Full-text

Biospeckle Optical Coherence Tomography (bOCT) in the Speedy Assessment of the Responses of the Seeds of Raphanus sativus L. (Kaiware Daikon) to Acid Mine Drainage (AMD)

Applied Sciences ◽

10.3390/app12010355 ◽

2021 ◽

Vol 12 (1) ◽

pp. 355

Author(s):

Danyang Li ◽

Uma Maheswari Rajagopalan ◽

Y. Sanath K. De Silva ◽

Fenwu Liu ◽

Hirofumi Kadono

Keyword(s):

Optical Coherence Tomography ◽

Acid Mine Drainage ◽

Mine Drainage ◽

Mineral Resources ◽

Vital Role ◽

Invasive Technique ◽

Optical Coherence ◽

Non Invasive ◽

Acid Mine ◽

Short Time

The extraction of mineral resources from mines plays a vital role in global socio-economic development. However, acid mine drainage (AMD) has been one of the major pollutants, and a vast area of the agricultural fields has been polluted. Therefore, techniques for monitoring the response of plants to AMD that arise during mineral extraction are necessary. In addition, such a technique becomes especially valuable to understand how the plants could play a role in the phytoremediation of AMD. We propose the use of biospeckle Optical Coherence Tomography (bOCT) to investigate the response of Kaiware daikon seeds under the exposure to simulated AMD at two different concentrations of 40 mL/L and 80 mL/L. OCT images of the Kaiware daikon seed were obtained at a speed of 10 frames per second (1 frame: 512 × 2048 pixels) for a few tens of seconds. For each pixel of the OCT structural images, the contrast across the temporal axis was calculated to give biospeckle contrast OCT images (bOCT images). It was found that bOCT images clearly distinguished the changes due to 40 mL/L and 80 mL/L of AMD treatments from the control within a short time of around an hour, compared to the conventional OCT images that failed to show any changes. This variation was found to be statistically significant and could reflect the internal activity of the seeds. The proposed bOCT method could be a rapid, non-invasive technique for screening suitable plants in AMD phytoremediation applications.

Download Full-text

Pachychoroid as a biomarker using optical coherence tomography – swept-source in central serous choroidopathy

Latin American Journal of Ophthalmology ◽

10.25259/lajo-7-2019 ◽

2019 ◽

Vol 2 ◽

pp. 3

Author(s):

René Alfredo Cano-Hidalgo ◽

Tatiana Urrea-Victoria

Keyword(s):

Optical Coherence Tomography ◽

Choroidal Thickness ◽

Invasive Technique ◽

Optical Coherence ◽

Horizontal Section ◽

Swept Source ◽

Non Invasive ◽

The Mean ◽

Foveal Center ◽

Fellow Eyes

Objective The objective of the study was to describe and evaluate the subfoveal choroidal thickness (SFCT) in the fellow eyes of patients with central serous chorioretinopathy (CSC) using swept source optical coherence tomography (SS-OCT). Methods This was a transversal, retrospective, and observational study. The SFCT was measured in patients with unilateral CSC using SS-OCT. The choroidal thickness in symptomatic and fellow eyes was measured using the attached measuring software in SS-OCT. The SFCT dimension was obtained from the horizontal section under the foveal center from the OCT data and these data were analyzed. Results The mean age of subjects undergoing imaging SS-OCT was 44.23 years old (standard deviation, 11.57). 30 out of 60 patients (63.3%) were men, and 20 (33.3%) patients had acute clinical disease. The median choroidal thicknesses of the affected eyes were greater than those of the unaffected fellow eyes (P = 0.06). The choroidal thickness measured in 120 eyes of (60 patients) was 421 µm (interquartile range 352–490), which was greater than the choroidal thickness reported in normal eyes. Conclusions The measuring of the choroidal thickness using SS-OCT is useful as a non-invasive technique to evaluate the subclinical choroidal abnormalities in CSC.

Download Full-text

Optical Coherence Tomography Angiography Findings After Intravitreal Ranibizumab in Patients With Coats Disease

Frontiers in Medicine ◽

10.3389/fmed.2020.615015 ◽

2021 ◽

Vol 7 ◽

Author(s):

Gilda Cennamo ◽

Daniela Montorio ◽

Chiara Comune ◽

Maria Paola Laezza ◽

Matteo Fallico ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Intravitreal Injections ◽

Invasive Technique ◽

Optical Coherence ◽

Intravitreal Ranibizumab ◽

Non Invasive ◽

Capillary Plexus ◽

Coats Disease ◽

Sd Oct

The aim of this retrospective study was to describe the vascular features in eyes with Coats disease, using optical coherence tomography angiography (OCTA), at baseline and after 3 monthly intravitreal injections of ranibizumab. Fifteen eyes of 15 consecutive patients affected by Coats' disease were recruited in this study. All patients underwent the best-corrected visual acuity (BCVA) evaluation, fundus examination, fluorescein angiography (FA), indocyanine green angiography (ICGA), multicolor imaging, structural Spectral Domain (SD)-OCT and OCTA at baseline and 1 month after the third monthly ranibizumab injection (loading phase). Fifteen patients completed the study, of whom nine were males and six females. Mean age was 20.4 ± 2 years. BCVA was 0.46 ± 0.11 logMar and 0.47 ± 0.12 logMar at baseline and after treatment, respectively (p = 0.164). SD-OCT revealed no significant decrease in central macular thickness (486.33 μm ± 93.37 at baseline vs. 483.4 μm ± 80.97 after treatment; p = 0.915). The subretinal exudates persisted in macular region after intravitreal injections. OCTA showed a general vascular rarefaction in superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillary (CC) that did not change after loading phase. This study showed no functional and vascular improvement following 3 monthly ranibizumab injections. OCTA, non-invasive technique, could be useful during follow up of these patients and provide a better understand of pathogenesis of this disorder.

Download Full-text

Line-Field Confocal Optical Coherence Tomography May Enhance Monitoring of Superficial Basal Cell Carcinoma Treated with Imiquimod 5% Cream: A Pilot Study

Cancers ◽

10.3390/cancers13194913 ◽

2021 ◽

Vol 13 (19) ◽

pp. 4913

Author(s):

Anna Elisa Verzì ◽

Giuseppe Micali ◽

Francesco Lacarrubba

Keyword(s):

Optical Coherence Tomography ◽

Pilot Study ◽

Basal Cell Carcinoma ◽

Cell Carcinoma ◽

Basal Cell ◽

Invasive Technique ◽

Optical Coherence ◽

Line Field ◽

Non Invasive ◽

Superficial Basal Cell Carcinoma

Line-field confocal optical coherence tomography (LC-OCT) is a novel, non-invasive technique for real-time skin imaging. Imiquimod (IQ) 5% cream is an immune response modifier currently approved for the treatment of small, superficial basal cell carcinoma (BCC). The aim of this study was to investigate if LC-OCT may be useful to enhance the treatment monitoring of BCC. Twenty superficial BCCs from 12 patients were treated with IQ 5% cream once daily, five days a week, for six weeks. Clinical and LC-OCT evaluations were performed at baseline and 4 weeks after the end of treatment. At the end of the study, 13 lesions showed a complete clinical and LC-OCT response, 4 lesions a partial clinical and LC-OCT response, and 3 lesions a complete clinical response but residual tumoral signs at LC-OCT. Our pilot study suggests that LC-OCT may represent a promising tool able to enhance the evaluation of the treatment response of BCCs to non-invasive treatments. In our case series, its use highlighted, through a detailed, fast, and complete examination of the treated area, three cases of residual BCC that otherwise would have gone undetected at clinical examination. Future studies on larger series of patients treated with different modalities and with a longer follow-up are advisable.

Download Full-text

Optical coherence tomography: a non-invasive technique applied to painting conservation

SPIE Newsroom ◽

10.1117/2.1200601.0067 ◽

2006 ◽

Author(s):

Haida Liang

Keyword(s):

Optical Coherence Tomography ◽

Invasive Technique ◽

Optical Coherence ◽

Non Invasive

Download Full-text

Non-invasive three-dimensional thickness analysis of oral epithelium based on optical coherence tomography—development and diagnostic performance

Heliyon ◽

10.1016/j.heliyon.2021.e06645 ◽

2021 ◽

Vol 7 (4) ◽

pp. e06645

Author(s):

Charlotte Theresa Trebing ◽

Sinan Sen ◽

Stefan Rues ◽

Christopher Herpel ◽

Maria Schöllhorn ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Diagnostic Performance ◽

Three Dimensional ◽

Oral Epithelium ◽

Optical Coherence ◽

Non Invasive

Download Full-text

949. Use of Optical Coherence Tomography Angiography to Assess Microvascular Health Among Persons with HIV: Employing the Retina as a Convenient Window

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1135 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S507-S507

Author(s):

Lauren F Collins ◽

Jessica G Shantha ◽

Peter L Nesper ◽

Anandi N Sheth ◽

Amani A Fawzi ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Retinal Vasculitis ◽

Organ Damage ◽

Screening Tools ◽

Foveal Avascular Zone ◽

Invasive Technique ◽

Optical Coherence ◽

Hiv Diagnosis ◽

The Right

Abstract Background Mechanisms underlying the rising burden of non-AIDS comorbidities (NACM) among persons with HIV (PWH) remain unclear. Microvasculopathy may link HIV-related chronic inflammation and premature multimorbidity, similar to diabetes and other conditions characterized by inflammatory end-organ damage. We used a novel retinovascular imaging tool, optical coherence tomography angiography (OCTA), to evaluate the retina as a convenient assessment of microvascular health among PWH. Methods Data from 4 PWH who underwent OCTA (Zeiss CIRRUSTM HD-OCT 5000) at the Emory Eye Center from 2018-2020 were analyzed. Demographics, HIV-specific indices and NACM were summarized at the time of OCTA. Images were reviewed qualitatively and metrics of microvascular health – the foveal avascular zone (FAZ) area and vessel density (VD) from the superficial capillary plexus (SCP) – were calculated by ImageJ. Results The median age was 39 years, 100% were male, 100% were black, 25% had ever smoked, and median body mass index was 25.4 kg/m2. Median time since HIV diagnosis was 19 years, all patients had a history of clinical AIDS, including 2 with prior cytomegalovirus retinitis. Median current CD4 count was 84 cells/mm3, 100% were prescribed antiretroviral therapy and 50% had HIV viral suppression. Prevalent NACM included (each n=1): hypertension, dyslipidemia, diabetes, chronic kidney disease and asthma. Qualitatively, all 7 of the eyes evaluated by OCTA had evidence of microvascular pathology: 2 eyes demonstrated diffuse capillary nonperfusion, while the remaining 5 eyes had focal areas of nonperfusion around the FAZ. Mean FAZ area was 0.31 (SD±0.10) mm2 and mean VD of the SCP was 43.9% (SD±10.9%). Retinovascular pathology identified by fundoscopy and OCTA is shown in the figure. Figure. Retinal imaging of a PWH with bilateral retinal vasculitis. Fundus photos of the right (A) and left (C) eyes show retinal vasculitis highlighted by the red arrows. OCTA of the right (B) and left (D) maculae (3X3 scan Zeiss AngioplexTM) show the FAZ areas outlined in yellow, both of irregular contour. OCTA of the left macula demonstrates areas of significant flow voids marked by the asterisks and the FAZ area is enlarged. Conclusion Among patients with longstanding HIV, OCTA identified microvascular abnormalities in all retinae examined. Retinovascular evaluation by OCTA is a feasible, non-invasive technique for assessing microvascular health and findings support additional study in a larger, more diverse group of PWH. Screening tools targeting microvasculopathy among PWH may aid in earlier detection of those at greatest risk of NACM and allow for aggressive risk-modification strategies. Disclosures All Authors: No reported disclosures

Download Full-text

Label-free non-invasive classification of rice seeds using optical coherence tomography assisted with deep neural network

Optics & Laser Technology ◽

10.1016/j.optlastec.2020.106861 ◽

2021 ◽

Vol 137 ◽

pp. 106861

Author(s):

Deepa Joshi ◽

Ankit Butola ◽

Sheetal Raosaheb Kanade ◽

Dilip K. Prasad ◽

S.V. Amitha Mithra ◽

...

Keyword(s):

Neural Network ◽

Optical Coherence Tomography ◽

Deep Neural Network ◽

Optical Coherence ◽

Label Free ◽

Non Invasive ◽

Rice Seeds

Download Full-text

Monitoring New Long-Lasting Intravitreal Formulation for Glaucoma with Vitreous Images Using Optical Coherence Tomography

Pharmaceutics ◽

10.3390/pharmaceutics13020217 ◽

2021 ◽

Vol 13 (2) ◽

pp. 217

Author(s):

Maria Jesus Rodrigo ◽

Amaya Pérez del Palomar ◽

Alberto Montolío ◽

Silvia Mendez-Martinez ◽

Manuel Subias ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Relative Intensity ◽

Therapeutic Option ◽

Pigment Epithelium ◽

Retinal Pigment ◽

Aggregate Size ◽

Daily Practice ◽

Optical Coherence ◽

Non Invasive ◽

Invasive Method

Intravitreal injection is the gold standard therapeutic option for posterior segment pathologies, and long-lasting release is necessary to avoid reinjections. There is no effective intravitreal treatment for glaucoma or other optic neuropathies in daily practice, nor is there a non-invasive method to monitor drug levels in the vitreous. Here we show that a glaucoma treatment combining a hypotensive and neuroprotective intravitreal formulation (IF) of brimonidine–Laponite (BRI/LAP) can be monitored non-invasively using vitreoretinal interface imaging captured with optical coherence tomography (OCT) over 24 weeks of follow-up. Qualitative and quantitative characterisation was achieved by analysing the changes in vitreous (VIT) signal intensity, expressed as a ratio of retinal pigment epithelium (RPE) intensity. Vitreous hyperreflective aggregates mixed in the vitreous and tended to settle on the retinal surface. Relative intensity and aggregate size progressively decreased over 24 weeks in treated rat eyes as the BRI/LAP IF degraded. VIT/RPE relative intensity and total aggregate area correlated with brimonidine levels measured in the eye. The OCT-derived VIT/RPE relative intensity may be a useful and objective marker for non-invasive monitoring of BRI/LAP IF.

Download Full-text