This study evaluates photodynamic therapeutic probes for peripheral lung cancer by a preclinical trial based on computational simulation. By light propagation simulation based on a Monte Carlo method, light distributions in tissues by a direct transmission light irradiation probe and a diffused light irradiation probe were calculated to compare each irradiated volume. The simulated results demonstrated quantitatively that the diffused light irradiation probe can irradiate the tumor tissue more efficiently than the direct transmission light irradiation probe for peripheral lung cancer.

Fluorescence Lifetime Imaging Ophthalmoscopy (FLIO) is a new imaging modality that measures and maps fluorescence lifetime at the ocular fundus using ultrashort pulse laser. FLIO has the potential to detect not only morphological changes but also subtle changes such as cellular metabolic change or accumulation of metabolism-related products. Therefore, FLIO might serve as a useful tool to detect early signs of diseases, monitor disease progression and evaluate therapeutic effect. This review introduces the principle of FLIO, basic and clinical knowledges to date, and describes the possible role of FLIO adjacent to the treatment of macular diseases.

Optical coherence tomography angiography (OCTA) is a novel method that non-invasively visualizes retinal blood flow in three dimensions. OCTA has advantages over fluorescein angiography in that it can help to visualize the retinal capillaries in higher contrast. Computational advances and use of artificial intelligence have enabled the visualization of a wider field of view with higher image quality, which has facilitated in reducing the gap between fluorescein angiography and OCTA. While OCTA is a very useful imaging modality, there are some unique artifacts in OCTA imaging, which should be taken into consideration when interpreting OCTA images.

Carotenoids, which are anti-oxidative agents, protect the human body from various oxidative stresses. Carotenoids exist as macular pigment in the retina and they are measured non-invasively by four methods; heterochromatic flicker photometry, fundus reflectometry, fundus autofluorescence spectroscopy, and resonance Raman spectroscopy. The relation between carotenoids and age-related macular degeneration (AMD) has been studied and the prophylactic effects of supplement containing lutein and zeaxanthin to AMD was reported. Skin carotenoids are measured non-invasively by reflectometry. They are highly correlated with blood concentration of carotenoids and the measurement of carotenoids is useful for food education since it reflects dietary intake.

Fundus microperimetry precisely measures regional light sensitivity at the specific area of the retina. The evaluation of the relationship between retinal pathology and retinal function is possible using fundus microperimetry. Fundus perimetry is very useful for making diagnosis, treatment, and follow-up of many macular disorders. The advancement of microperimetry instruments brings us more opportunities for accurate measurement and evaluation of various retinal functions.

Photodynamic therapy (PDT) in ophthalmology is a therapeutic modality for exudative age-related macular degeneration (AMD). PDT was expected to treat exudative lesion with minimum effect on normal tissue and became the first-choice intervention for AMD for years. However, when the visual outcome of PDT was reported to be inferior than that of the latest anti-VEGF therapy, PDT was no longer performed thereafter except of some specific phenotype of AMD which is still a good candidate of PDT by now. This review article summarizes the past and present of PDT in ophthalmology.

Since the 1960’s, laser therapy in the ophthalmologic field, especially for retinal diseases, has made various developments. Selective Retina Therapy (SRT) is one of the minimally invasive lasers that can selectively treat only retinal pigment epithelial cells without affecting the retina or choroid. We have reviewed the principle of SRT, clinical research, and future prospects.