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Binocular mechanisms for visual processing are thought to enhance spatial acuity by combining matched input from the two eyes. Studies in the primary visual cortex of carnivores and primates have confirmed that eye-specific neuronal response properties are largely matched. In recent years, the mouse has emerged as a prominent model for binocular visual processing, yet little is known about the spatial frequency tuning of binocular responses in mouse visual cortex. Using calcium imaging in awake mice of both sexes, we show that the spatial frequency preference of cortical responses to the contralateral eye is ∼35% higher than responses to the ipsilateral eye. Furthermore, we find that neurons in binocular visual cortex that respond only to the contralateral eye are tuned to higher spatial frequencies. Binocular neurons that are well matched in spatial frequency preference are also matched in orientation preference. In contrast, we observe that binocularly mismatched cells are more mismatched in orientation tuning. Furthermore, we find that contralateral responses are more direction-selective than ipsilateral responses and are strongly biased to the cardinal directions. The contralateral bias of high spatial frequency tuning was found in both awake and anesthetized recordings. The distinct properties of contralateral cortical responses may reflect the functional segregation of direction-selective, high spatial frequency-preferring neurons in earlier stages of the central visual pathway. Moreover, these results suggest that the development of binocularity and visual acuity may engage distinct circuits in the mouse visual system.SIGNIFICANCE STATEMENT Seeing through two eyes is thought to improve visual acuity by enhancing sensitivity to fine edges. Using calcium imaging of cellular responses in awake mice, we find surprising asymmetries in the spatial processing of eye-specific visual input in binocular primary visual cortex. The contralateral visual pathway is tuned to higher spatial frequencies than the ipsilateral pathway. At the highest spatial frequencies, the contralateral pathway strongly prefers to respond to visual stimuli along the cardinal (horizontal and vertical) axes. These results suggest that monocular, and not binocular, mechanisms set the limit of spatial acuity in mice. Furthermore, they suggest that the development of visual acuity and binocularity in mice involves different circuits.

Background: Lung herniation is a rare complication of heart–lung transplantation that can be fatal owing to vascular compromise and airway obstruction. To date, only five cases of lung herniation related to heart–lung transplantation have been reported in the literature; however, to the best of our knowledge, this is the first worldwide report of heart–lung transplantation‐related lung herniation in an infant. Methods: We describe the case of lung herniation as a rare heart–lung transplantation‐related complication in an infant. A 12‐month‐old female baby developed severe bronchopulmonary dysplasia with severe pulmonary hypertension, and she underwent extracorporeal membrane oxygenation for cardiac collapse and lung support. Then, we performed heart–lung transplantation to manage the irreversible deterioration of her lung function. After the heart‐lung transplantation, we found the radiological abnormalities persisted on follow‐up chest radiographs until the 13th postoperative day diagnosed as lung herniation of the right lower lobe on chest computed tomography. Results: After the relocation of the herniated lung, the clinical condition of the patient improved, and the patient is currently growing without any respiratory symptoms. Conclusions: In this case report, we emphasize that clinical awareness and high suspicion of this rare complication are needed for early diagnosis and proper treatment to prevent post‐transplantation morbidity and mortality related to potential ischemic injury. [ABSTRACT FROM AUTHOR]