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Abstract Background To report a case of interface fluid syndrome (IFS) following traumatic corneal perforation repair after small incision lenticule extraction (SMILE). Case presentation A 23-year-old woman, with a past history of SMILE, was struck in the left eye with a barbecue prod and subsequently underwent corneal perforation repair at local hospital. Primary wound repaired with a single 10 − 0 nylon suture at the area of leakage. After the surgery, her best corrected visual acuity (BCVA) was 20/30. Four days later, she presented at our hospital with blurred vision, and interface fluid syndrome (IFS) was diagnosed. Intraoperative optical coherence tomography (iOCT) was used to guide the resuturing of the corneal perforation in the left eye, followed by anterior chamber gas injection. At the first postoperative month, the BCVA was 20/25. The corneal cap adhered closely to the stroma, the surface became smooth. Conclusions This case illustrates that any corneal perforation following lamellar surgery, including SMILE, may lead to IFS. It is crucial to consider the depth of corneal perforation, and intraoperative optical coherence tomography (iOCT) plays a unique role in the repair procedure.

Exosomes are extracellular vesicles that facilitate cellular communication by transmitting biomolecules and altering the biochemical characteristics of receptor cells. Mesenchymal stem cell-derived exosomes(MSC-Exos)are lipid bilayer vesicles secreted by mesenchymal stem cells(MSCs). These exosomes have similar functions to MSCs and contain bioactive substances such as proteins, lipids, and nucleic acids. MSC-Exos play a vital role in intercellular communication and are involved in essential physiological processes including immune regulation, tissue damage repair, and angiogenesis promotion. Consequently, they have gained significant attention in research, particularly in the treatment of immune inflammatory diseases, ischemic diseases, and other related fields. This article provides an in-depth analysis of the potential treatment mechanisms for dry eye, focusing on the pathogenesis of the condition, including inflammatory reactions, nerve regeneration, and tissue repair. The objective is to establish a foundation for the application of MSC-Exos in the treatment of dry eye, thereby offering a valuable reference for the future clinical applications.

Objective To evaluate the clinical values of preoperative 99mTc-methoxyisobutylisonitrile (MIBI) pinhole collimator duplex imaging versus parallel-hole collimator single photon emission computed tomography (SPECT)/CT tomography fusion imaging in the preoperative localization of primary hyperparathyroidism (PHPT). Methods In this diagnostic test, the patients with suspected PHPT in Peking Union Medical College Hospital from July 2021 to February 2022 were retrospectively analyzed. With postoperative histopathology as the gold standard, the sensitivity, accuracy, and positive predictive value of 99mTc-MIBI pinhole collimator duplex imaging and parallel-hole collimator SPECT/CT tomographic fusion imaging for the detection of PHPT lesions were calculated, and the effect of parathyroid hormone (PTH) on the detection of PHPT lesions by these two diagnostic methods was analyzed. Results A total of 135 patients with suspected PHPT on 99mTc-MIBI parathyroid imaging were enrolled. A total of 149 lesions were detected on 99mTc-MIBI pinhole collimator diachronic imaging (including 1 ectopic lesion) and 148 lesions were detected on parallel-hole collimator SPECT/CT tomographic fusion imaging (including 11 ectopic lesions; 1 true positive lesion was a fusion of 2 lesions that could not be distinguished by this method). The sensitivity (79.9% vs. 74.8%, P=0.326), accuracy (79.2% vs. 75.7%, P=0.490) and positive predictive value (98.3% vs. 100%, P=0.499) of the two methods for detecting PHPT lesions were not significantly different. In the subgroups with PTH≤150 ng/L and PTH>150 ng/L, the sensitivity (79.1% vs. 80.5%, P=0.838), accuracy (77.5% vs. 80.8%, P=0.688), and positive predictive value (96.4% vs. 100%, P=0.219) of 99mTc-MIBI pinhole collimator diachronic imaging in detecting PHPT lesions were not significantly different; the sensitivity (71.6% vs. 77.6%, P=0.445), accuracy (73.2% vs. 77.9%, P=0.567), and positive predictive value (100% vs. 100%, P> 0.999) of SPECT/CT fusion imaging were also not significantly different. Conclusions Both 99mTc-MIBI pinhole collimator parathyroid duplex imaging and parallel-hole collimator SPECT/CT tomographic fusion imaging have good diagnostic ability for PHPT and are not significantly affected by changes in PTH levels. Due to the high resolution of 99mTc-MIBI pinhole collimator parathyroid duplex imaging, it is still an important basis for preoperative localization and diagnosis of PHPT, while parallel-hole collimator SPECT/CT tomographic fusion imaging has obvious advantages for the diagnosis of ectopic PHPT and is recommended in some special cases.

The catalysts performance degradation is a crucial issue in decay of the polymer electrolyte membrane fuel cell (PEMFC). The effect of Nafion content, dispersity of Pt nanoparticles and selected types of carbon support on the degradation of electrochemical surface area (ECSA) and double layer capacitance (DLC) were experimentally discussed by accelerated stress test (AST). The catalyst with 20wt% Nafion content exhibited better catalyst performance. i.e., the less DLC and ECSA degradation during AST. Catalysts with well Pt dispersity showed superior %ECSA (the percentage change of ECSA) retention. The heat-treated catalysts exhibited the lowest ECSA and DLC degradation rate due to the larger Pt particle and high carbon corrosion resistance. Moreover, a multi-order model describing the correlation between ECSA and DLC degradation was proposed, providing a vital reference for quantitatively investigating ECSA and DLC degradation in the catalysts with different catalysts structural parameters.