Splenic aneurysm

　　1. Congenital arterial tissue defect  Casgrove believed in 1947, based on pathological examination, that the atrophy and defect of the middle layer tissue and elastic fiber layer of the splenic artery are important causes of splenic aneurysm formation. In addition, splenic aneurysms can coexist with aneurysms in other parts of the body, such as common aortic aneurysms and intracranial aneurysms. However, this multifocal aneurysm accounts for only about 10% of all splenic aneurysm cases. Therefore, congenital arterial structural defects cannot fully explain the etiology of this disease.

　　2. Portal hypertension  In a group of 229 splenic aneurysms, 20% were accompanied by liver cirrhosis and portal hypertension. In the group of 159 cases of Owens, the same proportion of portal hypertension patients were also found. In a group of 220 cases of portal hypertension in China, 73 underwent surgical treatment, among whom 2 were found to have splenic aneurysms. This indicates that portal hypertension is related to the occurrence of splenic aneurysms.

　　3. Atherosclerosis  Among the 159 splenic aneurysms collected by Owens, 96 cases (60%) had atherosclerotic lesions, intimal hyaline degeneration, or calcification in the splenic artery, which was winding and tortuous, mostly in elderly patients.

　　4. Trauma  Especially penetrating injuries or gunshot wounds to the upper abdomen, such as injuries to the splenic artery, can cause this disease.

　　5. Pregnancy  Pregnancy is closely related to the occurrence of splenic aneurysms. Statistics show that splenic aneurysms occur more frequently in women, with an incidence that can be 2 to 4 times higher than that in men, especially in women who have had multiple pregnancies. About 20% of splenic aneurysm patients are pregnant women, which is enough to illustrate the relationship between the two. However, the exact etiology is still unclear, and whether the endocrine changes and hemodynamic changes during pregnancy can lead to arterial lesions cannot be fully confirmed.

　　6. Valvular heart disease and splenic artery embolism  About 23% of splenic aneurysm patients have thrombus formation in the splenic artery during pathological examination, and the vast majority of these patients have heart valve lesions.

　　7. Splenic arteritis  Systemic large artery arteritis or simple splenic arteritis can cause glassy degeneration of the arterial wall, even纤维素性坏死, the wall is fragile, prone to local expansion of the arterial wall, and can gradually develop into splenic aneurysm.

　　8. Syphilis  It is a component of systemic syphilis infection lesions.

　　9. Fungal infection  It manifests as local splenic artery lesions.

　　The most dangerous complication of splenic aneurysm is acute rupture of the aneurysm body causing massive hemorrhage. One report states that the fetal mortality rate is greater than 95% and the maternal mortality rate is greater than 70% during pregnancy when splenic aneurysm rupture occurs, and the mortality rate of splenic aneurysm rupture in other situations (non-pregnant individuals) is greater than 25%.

　　Before the rupture of splenic aneurysm, there are usually no obvious symptoms, with occasional discomfort in the upper left abdomen. Once obvious symptoms such as pain in the upper left abdomen or left hypochondriac region, nausea, and vomiting appear, it often indicates the pre-mature rupture of the aneurysm. After rupture, there are symptoms such as severe upper abdominal pain and radiation pain in the left shoulder (Kehr sign), tenderness under the left costal margin, hypotension, and shock.

　　Some splenic aneurysms present with rupture and bleeding as the initial symptom, followed by shock and even death. If it breaks into the small omental sac, it can temporarily stop bleeding due to blood clot filling and compression, but it can break again through the Winslow foramen into the peritoneal cavity. In rare cases, the tumor body can also form an arteriovenous fistula with the portal venous system, causing portal hypertension.

　　Splenic aneurysm is a relatively rare vascular disease that is often misdiagnosed in clinical practice. About 22% of patients discover they have a splenic aneurysm only after the aneurysm body ruptures. The mortality rate of aneurysm rupture is about 8.5%. Therefore, the understanding of splenic aneurysm by clinical doctors is helpful for early diagnosis and treatment of this disease, which is the key to alleviating the threat of this disease to patients' lives.

　　1. Abdominal flat film and angiography  This disease has a hidden onset, so the vast majority of patients are occasionally found to have this disease during non-targeted abdominal imaging examinations. Typical signs include: a curved or annular calcification shadow in the upper left abdomen. Currently, angiography remains the 'gold standard' for the diagnosis of visceral aneurysms. It can reveal the exact location of the aneurysm and help determine whether there are other aneurysms. When the aneurysm is located in the main trunk of a large blood vessel, the pressure and flow rate of the contrast medium should be appropriately reduced to prevent the rupture of the aneurysm.

　　2. Ultrasonic and Color Doppler examination  Ultrasonic examination can detect typical aneurysm manifestations, with blood flow present in the cystic dark area. Color Doppler can further clarify the blood flow velocity within the blood vessels and whether there is an embolism phenomenon.

　　3. CT and MRA  Advanced spiral CT can perform three-dimensional reconstruction of images, helping to identify the relationship between tumors and adjacent organs, providing great convenience for surgery. Magnetic resonance angiography is a relatively new non-invasive vascular imaging diagnostic technique. In the past, due to technical factors, the application of MRA in the diagnosis of abdominal aortic system diseases was limited.

　　Recently, MRA has made new breakthroughs, known as three-dimensional enhanced contrast magnetic resonance angiography, which uses gadolinium as a vascular contrast agent. This technology has T-1 shortening effects, removes blood flow signals, thereby overcoming the interference of blood saturation and turbulent signals. Abdominal large-volume imaging signals can be obtained quickly, and various three-dimensional reconstructions can be performed along the vascular axis. The obtained images are similar to those of angiography and spiral CT imaging. Due to the use of non-ionic contrast agents, it avoids the side effects of contrast agents and possible allergic reactions, and has high safety for patients with renal insufficiency, making it a promising vascular imaging method.

　　Dietary taboos:
　　Avoid greasy, cold, and difficult-to-digest foods that are刺激性.

　　Appropriate Diet:
　　Easily digestible foods that promote defecation. Such as vegetables: kelp, pork blood, carrots, etc.; fruits: hawthorn, pineapple, papaya, etc.; eating more fiber-rich foods such as various vegetables, fruits, brown rice, whole grains, and beans can help defecate, prevent constipation, stabilize blood sugar, and reduce blood cholesterol.

　　1. Surgical Treatment

　　The most ideal treatment for splenic aneurysm is to surgically remove it before it ruptures, and the surgical indications are:

　　(1) Those with obvious symptoms, suspected of being a precursor to rupture or already ruptured and bleeding;

　　(2) Tumor diameter ≥ 2cm;

　　(3) Tumor diameter
　　(4) Pregnant women or women of childbearing age should be scheduled for surgery before or during pregnancy;

　　(5) Splenic aneurysms found accidentally during laparotomy should also be removed if the condition allows.

　　(6) Splenic aneurysms caused by adjacent organ lesions, trauma, infection, etc., should also be surgically removed as soon as possible.

　　2. Interventional Treatment

　　In recent years, with the advancement of interventional techniques, the treatment of splenic aneurysms with splenic artery embolization, splenic artery stent-grafting, and spring栓塞术 assisted by bare stents has achieved good results. Currently, endovascular interventional treatment has become the first-line treatment for splenic artery.