Arterial spin labeling (ASL) technique is a kind of perfusion functional magnetic resonance imaging method that is based on endogenous contrast, and it can measure cerebral blood flow (CBF) noninvasively. The ASL technique has advantages of noninvasiveness, simplicity and relatively lower costs so that it is more suitable for longitudinal studies compared with previous perfusion methods, such as positron emission tomography (PET), single photon emission computed tomography (SPECT), CT and the contrast agent based magnetic resonance perfusion imaging. This paper mainly discusses the current clinical applications of ASL in brain diseases as cerebrovascular diseases, brain tumors, Alzheimer's disease and epilepsy, etc.
Animals ; Brain Diseases ; diagnosis ; Brain Neoplasms ; diagnosis ; Cerebrovascular Circulation ; Cerebrovascular Disorders ; diagnosis ; Humans ; Magnetic Resonance Imaging ; methods ; Perfusion ; Spin Labels

Purpose: To evaluate the effect of corneal nerves assessment on predicting corneal complications following pars plana vitrectomy (PPV). Methods: In this prospective single-center cohort study, 94 patients (94 eyes) received PPV, and were divided into postoperative groups with and without corneal complications. All eyes had corneal nerve fiber length (CNFL), corneal nerve fiber density, and branch density of corneal nerve fibers assessed and calculated with Image J preoperatively. Multivariate logistic regression analysis was used to identify corneal nerve fiber parameters that correlated to post-operative corneal complications. Receiver operator characteristic curve analysis was performed to identify the optimal cut-off point of the corneal fibers’ parameters for predicting corneal complications after PPV. Results: Eleven eyes (11.70%) developed corneal complications at 1 week after PPV. There was significant difference between CNFL (19.44 ± 6.88 vs. 26.84 ± 7.53, p = 0.003), corneal nerve fiber density (28.82 ± 9.91 vs. 37.10 ± 10.16, p = 0.013) and branch density of corneal nerve fibers (55.84 ± 21.08 vs. 82.04 ± 31.89, p = 0.01) in two groups, respectively. Receiver operator characteristic analysis showed that the optimal cutoff value of CNFL to predict corneal complications following PPV was <26.495 mm/mm2. Conclusions The decrease of CNFL may predict corneal complications following PPV. Regular preoperative corneal confocal microscopy test in PPV patients could be considered.

Purpose: To evaluate the effect of corneal nerves assessment on predicting corneal complications following pars plana vitrectomy (PPV). Methods: In this prospective single-center cohort study, 94 patients (94 eyes) received PPV, and were divided into postoperative groups with and without corneal complications. All eyes had corneal nerve fiber length (CNFL), corneal nerve fiber density, and branch density of corneal nerve fibers assessed and calculated with Image J preoperatively. Multivariate logistic regression analysis was used to identify corneal nerve fiber parameters that correlated to post-operative corneal complications. Receiver operator characteristic curve analysis was performed to identify the optimal cut-off point of the corneal fibers’ parameters for predicting corneal complications after PPV. Results: Eleven eyes (11.70%) developed corneal complications at 1 week after PPV. There was significant difference between CNFL (19.44 ± 6.88 vs. 26.84 ± 7.53, p = 0.003), corneal nerve fiber density (28.82 ± 9.91 vs. 37.10 ± 10.16, p = 0.013) and branch density of corneal nerve fibers (55.84 ± 21.08 vs. 82.04 ± 31.89, p = 0.01) in two groups, respectively. Receiver operator characteristic analysis showed that the optimal cutoff value of CNFL to predict corneal complications following PPV was <26.495 mm/mm2. Conclusions The decrease of CNFL may predict corneal complications following PPV. Regular preoperative corneal confocal microscopy test in PPV patients could be considered.

Ischemic optic neuropathy(ION)is a common eye disease that could cause blindness. ION can be classified as anterior ischemic optic neuropathy(AION)or posterior ischemic optic neuropathy(PION)according to the presence or absence of optic disc edema. AION is more prevalent(90%). Moreover, ION can be divided into arteritic ION and non-arteritic ION based on the presence or absence of vasculitis. While various forms of ION may present comparable clinical symptoms, they differ considerably in terms of etiology, prognosis, and treatment approaches.Arteritic ION has the potential to cause blindness, disability, and even mortality in a short period of time. Therefore, early detection of arteritis and determination of the need for corticosteroid therapy are essential for the treatment of ION. The positive significance of identifying and managing potential modifiable risk factors for ION lies in its ability to prevent recurrence in both the affected and contralateral eyes. This article reviews the etiology, risk factors, diagnosis, and management of various varieties of ION with the goal of reducing misdiagnosis and improper treatment, thereby enhancing the overall prognosis of this condition.

Over half a century has passed since the inception of vitrectomy, and the indications for its utilization in ophthalmology encompass the majority of vitreoretinal disorders. Technological advancements and equipment innovation have drastically reduced the surgical risk of vitrectomy, but some complications remain unavoidable. Occasionally, unexpected or unexplained visual impairments can manifest. Vitrectomy is associated with a high incidence of optic neuropathy, which can manifest weeks to months following the procedure and result in permanent visual impairment. An intraoperative optic nerve injury and a postoperative secondary injury comprise the causes. Intraocular pressure, dye toxicity, or mechanical damage can cause intraoperative optic nerve injury. Secondary injuries that occur after surgery include an increase in intraocular pressure, toxicity to silicone oil, oxidative stress, and other alterations in the microenvironment. This review will discuss the common causes, clinical manifestations, and related management of optic neuropathy connected to vitrectomy in order to attract the interest of ophthalmologists.

Purpose: To assess the feasibility of applying ultra-widefield fundus (UWF) images for macular staphyloma area (MSA) measurement and investigate the associated factors with MSA. Methods: This is a retrospective study. MSA was measured by UWF imaging. Central foveal thickness, subfoveal choroidal thickness, subfoveal scleral thickness were measured on spectral domain optical coherence tomography. Intraclass correlation coefficients of MSA measurement would be evaluated. Multiple linear regression analysis was used to analyze the associated factors with MSA. Results: In total, 135 eyes of 92 patients were enrolled. The mean age was 64.73 ± 10.84 years. Mean MSA on UWF image was 279.67 ± 71.70 mm2. Intraclass correlation coefficients of MSA measurement was 0.965 (95% confidence interval [CI], 0.946 to 0.977; p < 0.001). In the multiple linear regression analysis, after adjusting for subfoveal choroidal thickness, best-corrected visual acuity, central foveal thickness, and subfoveal scleral thickness, the factors independently related to MSA were axial length (β = 8.352; 95% CI, 3.306 to 13.398; p = 0.001), sex (β = -26.673; 95% CI, -51.759 to -1.586; p = 0.037), age (β = 1.184; 95% CI, 0.020 to 2.348; p = 0.046). Conclusions It is feasible to measure MSA on UWF image. Female, longer axial length, and older age may indicate larger MSA.