Clinical analysis of pipeline dredging agent poisoning: A case report

Figure 1 Comparison of facial manifestations before and after therapy. A: Upon admission, there are scattered black burn marks on the face, especially in the nasolabial sulcus on both sides. Slightly limited mouth opening (approximately 2.5 cm). Mucous membranes, such as the lips and tongue, were black with obvious ulceration and bleeding; B: 7 d after therapy, the black burn marks on the face were less than before, and the bleeding of lip and tongue ulcer had reduced slightly. However, the mouth opening remained limited.