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In order to obtain the in-situ stress field characteristics and analyze tectonic stability in the Motuo key area of the eastern Himalayan syntaxis, the in-situ stress measurement of one in-situ stress hole and 11 test sections of the Xirang section of the Motuo fault zone were carried out by the hydraulic fracturing method. The results show that the maximum and minimum horizontal principal stress values (SH, Sh) in the test section of 61.43−121.34 m are 3.05−14.50 MPa and 2.16−9.87 MPa, respectively, and the vertical principal stress values (Sv) are 1.63−3.31 MPa, namely, SH>Sh>Sv. The in-situ stress field at the measuring point is dominated by horizontal compression, and all of them belong to the in-situ stress state of reverse fault. The principal stress values gradually increase with the increase of depth, and the dominant direction of the maximum principal stress is NEE. In the whole range of in-situ stress depth, the lateral pressure coefficients (Kav) are 1.39−4.38, the maximum horizontal stress coefficients (KHv) are greater than 1, and the ratio increases with the increase of depth. The regional stress field of this key area is dominated by horizontal stress and it is highly directional. The horizontal stress coefficients (KHh) of all test sections are 1.23−1.66, which are similar to the calculation results of in-situ stress characteristic parameters in Linzhi−Tongmai section. The horizontal tectonic stress of the shallow level at 98 m is relatively small, and the stress accumulation level is low. The friction coefficient required to maintain fault stability is smaller than the critical friction coefficient of actual fault, and the tectonic environment is relatively stable. When the depth exceeds 98 m, the friction coefficient required to maintain fault stability is close to the critical friction coefficient value of the actual fault due to the dominant role of horizontal tectonic stress, and there is a small risk of fault instability slip. The superposition of the Coulomb stress change in the sinistral strike-slip direction and the thrust direction caused by the strong regional earthquakes on the fault plane of the Motuo fault zone in the study area are all negative numbers, which inhibits fault slip and does not increase the risk of fault activity in the study area.

The Namjag Barwa syntaxis is in the eastern Himalayan syntaxis area with the most intensive neotectonic activity. There are many late Quaternary active fault belts and strong seismicities. The tectonic stability of these active fault belts, such as the Jiali, Dongjiu-Milin, and Motuo fault belts, may influence the project's construction. In-situ stress is a critical parameter for estimating regional tectonic stability. Currently, there is a lack of abundant in-situ stress results about the Namjag Barwa syntaxis. It is challenging to assess geological safety risks for major projects. Based on focal mechanism solutions, the paper reveals the orientation of the maximum principal stress surrounding the Namjag Barwa syntaxis using the stress tensor inversion method. According to the critical condition of fault instability, the magnitudes of principal stresses around the Namjag Barwa syntaxis are also estimated by combining the inversion of the stress shape ratio and the frictional coefficient. The results indicate that the maximum principal stress direction in the Namjag Barwa syntaxis area is NE-NNE. The maximum and minimum horizontal principal stresses increase linearly with depth at a gradient of 0.032~0.0355 MPa/m and 0.0227~0.0236 MPa/m, respectively. Heterogeneous features of the in-situ stress field still exist. Generally, the results estimated in this study are in good concordance with the in-situ stress measurements. They can provide reliable in-situ stress parameters for evaluating the tectonic stability in the Namcha Barwa region.

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Severe corneal ulcerations, causing major keratolysis with large perforation of the cornea or extending to the limbal region, are an ophthalmic emergency. In these cases, a larger corneoscleral graft can be transplanted to restore tectonic integrity, alleviate pain, save vision, and prevent loss of the eye. Chart review of 34 patients with a corneoscleral graft ≥9.5 mm was conducted. Primary endpoints of the study were tectonic stability defined as no need for another keratoplasty or enucleation. In addition, visual acuity, postoperative complications, and secondary procedures were analyzed. In total, 12 patients (35%) were female. The mean age at transplantation was 65 ± 19 years. The underlying disease was a perforated infectious corneal ulcer in 30 cases (88%). Mean follow up was 675 ± 789 days. Tectonic stability at the end of the follow-up was maintained with a probability of 56% in a Kaplan–Meier analysis. Another penetrating keratoplasty was necessary in six cases (17%) and enucleation in five cases (15%). A corneoscleral transplant remains a viable treatment option to prevent enucleation in severe keratolysis. In our study, this was possible in about half of the cases. Postoperative complications, secondary surgeries, and markedly reduced visual acuity put the advantages into perspective.

Severe corneal ulcerations, causing major keratolysis with large perforation of the cornea or extending to the limbal region, are an ophthalmic emergency. In these cases, a larger corneoscleral graft can be transplanted to restore tectonic integrity, alleviate pain, save vision, and prevent loss of the eye. Chart review of 34 patients with a corneoscleral graft ≥9.5 mm was conducted. Primary endpoints of the study were tectonic stability defined as no need for another keratoplasty or enucleation. In addition, visual acuity, postoperative complications, and secondary procedures were analyzed. In total, 12 patients (35%) were female. The mean age at transplantation was 65 ± 19 years. The underlying disease was a perforated infectious corneal ulcer in 30 cases (88%). Mean follow up was 675 ± 789 days. Tectonic stability at the end of the follow-up was maintained with a probability of 56% in a Kaplan-Meier analysis. Another penetrating keratoplasty was necessary in six cases (17%) and enucleation in five cases (15%). A corneoscleral transplant remains a viable treatment option to prevent enucleation in severe keratolysis. In our study, this was possible in about half of the cases. Postoperative complications, secondary surgeries, and markedly reduced visual acuity put the advantages into perspective.