br Discussion Anastomotic aneurysm formation following extra

Discussion Anastomotic aneurysm formation following extracranial-intracranial (EC-IC) surgery is relatively uncommon. In previously reported cases (Table 1), pseudoaneurysm formation was mostly observed during the first 2 postoperative months, whereas true aneurysms were observed years after surgery (Figure 5A). Most patients presented with a ruptured aneurysm with unfavorable outcomes (Figure 5B). Once ICH is diagnosed through postoperative TAK-242 CT, more aggressive follow-up through postoperative CT angiography is crucial to prevent catastrophic sequelae. In addition, life-long follow-up is mandatory for such patients. In addition to aneurysm formation, the STA–MCA bypass procedure can cause several potential complications. Ischemic changes usually result from the compression of the donor vessel because of scalp closure, graft occlusion, stenosis at the anastomotic site, and embolism. Therefore, the treating physician must look for evidence of the phenomena. Generally, postoperative Doppler and angiography can be used to identify the cause. Hypertension may result in anastomosis leakage or parenchymal hemorrhage, and increased perfusion may subsequently cause cerebral edema and impaired autoregulation. In addition, a loose dural closure is necessary to prevent the compression of the donor vessel, which increases the risk of cerebrospinal fluid leakage, pseudomeningocele, and subdural hygromas. Finally, similar to other craniotomies, systemic surgical complications such as myocardial infarction, pneumonia, deep venous thrombosis, and pulmonary emboli may occur. Some case studies have reported aneurysm formation following STA–MCA bypass. Several theories have been postulated to explain this complication. This complication may be attributed to a problem in the surgical technique, traumatic vascular injury during surgery, or hemodynamic changes after a bypass procedure. Robertson and Robertson conducted a study on rats and reported that the number of anastomosis sutures is closely associated with the potency rate and pseudoaneurysm formation. For end-to-side anastomosis with vessels measuring 1–2 mm in diameter, at least 12 sutures are recommended. In the aforementioned study, pseudoaneurysm formation was noted 5 weeks after anastomosis. Another mechanism proposed for aneurysm formation is the disruption of the intima of vessels as a result of intraoperative manipulation. The number of sutures used and the damage to the intima may explain, at least in part, the formation of a pseudoaneurysm postoperatively. However, the formation of a true aneurysm has also been mentioned in other case reports (Table 1). The effect of hemodynamic changes after a bypass procedure has been discussed. To maintain stable local cerebral blood flow, blood flow through either moyamoya vessels or bypass vessels should increase to balance the reduced flow volume from the occlusive internal cerebral artery. The increased blood flow is considered to exert a strong shearing force on the vessel walls, particularly at the bifurcation site, and a true aneurysm may form opposite to the STA insertion site.
Conclusion
Introduction Spontaneous ureteral rupture is defined as the nontraumatic leakage of urine from the ureter. It is a rare condition and a potential urological emergency. Here, we present the rare case of a patient diagnosed with spontaneous ureteral rupture leading to urinoma. Although uncommon, emergency physicians must have knowledge regarding this condition, which often presents as an acute abdominal condition and may be misdiagnosed as acute appendicitis or diverticulitis.
Case Report A 65-year-old man with a history of iron-deficiency anemia was referred to our emergency department with a 2-day history of abdominal distension and flank pain. On arrival, his vital signs were stable, and his body temperature was 36.6°C. Physical examination revealed costovertebral angle knocking pain on either side, and whole abdominal distension without muscle guarding and rebound tenderness. Laboratory studies revealed no abnormalities except microscopic hematuria. Abdominal radiography showed retention of fecal material in the colon. On the basis of persistent abdominal and flank pain, we suspected ascending colonic or cecal diverticulitis and/or appendicitis; therefore, an emergency abdominal computed tomography (CT) was performed. Abdominal CT revealed luminal stenosis and an obstructive lesion in the right upper ureter complicated by right obstructive uropathy and mild hydronephrosis. The leakage of urine from the right renal pelvis and ureteropelvic junction had led to the formation of urinoma within the right perirenal and pararenal space of the retroperitoneum (Figure 1). The patient initially received an urgent right percutaneous nephrostomy and treatment with broad-spectrum antibiotics. On the 2nd day, radiolucent ureteral stones were removed through ureterorenoscopic manipulation and double-J stenting. After 5 days, the patient’s condition considerably improved, and bedside ultrasonography revealed the disappearance of the perirenal and pararenal fluid collection. The patient was discharged 6 days after admission.