Critical flicker fusion frequency (CFF) is a dynamic visual function test that measures the minimum frequency at which a flicker source is perceived by the visual system as continuous light. The measurement method is convenient, the inspection time is short, and it can be effectively evaluated in the case of refractive interstitial opacity. Although CFF has many advantages, its application in the field of ophthalmology has not received sufficient attention. The pathway of CFF involves the pathway from the retina to the lateral geniculate body to the primary visual cortex, where the macrocellular pathway is sensitive to temporal resolution and responsible for transmitting rapidly changing information. Its measurements typically use red, green, or yellow light as a flashing light source to detect the functional integrity of the macular region. As a subjective test, the results of CFF can be affected by a variety of factors, such as drug use, fatigue, and luminous intensity. In order to improve the repeatability of the measurement, it is necessary to follow standardized measurement steps. CFF has important application value in the diagnosis of optic nerve diseases. It can assist in diagnosing the presence of optic neuropathy, evaluating the conduction function of the optic nerve, and monitoring the progression of the disease and the effect of treatment. As a convenient and efficient visual function evaluation tool, CFF has great potential in the diagnosis of optic nerve diseases and visual function monitoring. In view of its application prospects in the field of ophthalmology, this study calls for more attention and support from ophthalmologists, and carry out related basic and clinical research to further explore the application value of CFF in different disease conditions.
Neuromyelitis optica spectrum disorder (NMOSD) is a kind of demyelinating disease of central nervous system which mainly affect optic nerve and spinal cord. Because of its serious blindness and disability, how to effectively prevent relapse has become the focus of ophthalmologists. With the deep understanding of the pathogenesis and the progress of scientific and technological means, more and more monoclonal antibodies(mAb) continue to enter clinical trials. B cell surface antigen CD20 blocker, rituximab, has become a first-line drug for the treatment of NMOSD. CD19 blocker, inebilizumab, can reduce the recurrence and disability of NMOSD patients. The addition of interleukin 6 receptor blocker, satralizumab, and complement C5 inhibitor, eculizumab, reduce the recurrence. Some mAbs such as natalizumab and alemtuzumab may not be effective for the treatment of NMOSD. The expansion of mAb treatment indications and the launch of new drugs still require more clinical trials which are large-scale and international cooperation. At the same time, its potential adverse events and cost issues cannot be ignored.
On September 27, 2022, the first international standard of Diagnosis and Classification of Optic Neuritis was published online in Lancet Neurology, the top journal of neurology. The publication of this standard fills the gap in the international diagnosis and classification of optic neuritis (ON), promotes the consistency of the global diagnosis classification of ON, and helps ophthalmologists and neurologists to diagnose ON more accurately in the future. In recent decades, although Chinese ophthalmologists have made great progress in their understanding of ON and diagnosis and treatment level, it is still necessary to continue to strengthen the standardized training of Chinese neuro-ophthalmologist specialists, cooperate to establish a national ON clinical epidemiology database, carry out Chinese multi-center clinical studies, and further verify and optimize the international ON diagnostic system in future clinical practice. The ON diagnostic standards and treatment standards are gradually improved for China.
Neuromyelitis optica-related optic neuritis (NMO-ON) is a kind of severe optic nerve disease, which always leads to replase, poor prognosis, and even blindness. Aquaporin 4 antibody (AQP4-IgG) is the main diagnostic biomarker for neuromyelitis optica with high specificity. Serum myelin oligodendrocyte glycoprotein antibody (MOG-IgG) is helpful for the diagnosis of AQP4-IgG negative patients. The study of biomarkers is helpful to deeply understand the pathogenesis of NMO-ON, help the diagnosis of the disease, and finally make precise treatment. Orbital MRI can help to differentiate MOG-IgG positive from AQP4-IgG positive neuromyelitis optica and optic neuritis, which is very important for the diagnosis of NMO-ON. At present, the standardized treatment of NMO-ON can be divided into two clinical stages: acute stage and remission stage. Corticosteroids and plasma exchange are the main treatments in acute stage, aiming at alleviating acute inflammatory reaction and improving prognosis. Immunosuppressive agents and biological agents are the main treatments in remission stage, aiming at preventing or reducing recurrence. With the development of the diagnosis and treatment of NMO-ON, we find that it is more and more important to strengthen the construction of neuro-ophthalmology team in China, establish clinical epidemiological database of NMO-ON, and carry out multi-centre, large-sample, prospective clinical control studies in China to provide evidence-based medicine for Chinese people. In addition, we need to strengthen efforts to establish and improve the diagnostic criteria for NMO-ON and the promotion of diagnostic and therapeutic criteria, and strive to improve the clinical diagnosis and treatment level of NMO-ON in China.
Neuro-ophthalmology is an interdisciplinary discipline that spans multiple disciplines such as ophthalmology, neurology, and neurosurgery, and plays an important role in ophthalmology. Since the establishment of the Neuro-Ophthalmology Group in 2011, it has shown a good momentum of accelerated development of neuroophthalmology team building, promoting the process of neuroophthalmology standardization and strengthening interdisciplinary cooperation. However, there is still a gap between the level of neuro-ophthalmology in China and that in developed countries, which still cannot get rid of the stage of introduction and imitation. It is still a long way to form neuro-ophthalmology with unique characteristics in China. In the future, we should carry out clinical research while advancing basic research work, and establish a standard training system to strengthen the training of neuroophthalmologists. It is expected that in the next 10 years, China's neuro-ophthalmic diagnosis and research level will be significantly improved, and a number of landmark academic achievements will be achieved, and a number of internationally and domestically renowned neuro-ophthalmologist will be trained to further enhance the international academic status of neuro-ophthalmic research in China.