spleen disease

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Spleen Disease,The splenic primordium becomes,evident during the fifth week of,gestation as an outgrowth of the,dorsal mesogastrium, which,migrates to the left upper quadrant.,The gross appearance of the spleen,is the result of its development,from multiple anlage, resulting,in an organ with multiple clefts.,Embryoiogy,12 to 15 cm in,length, 4 to 8 cm in,width and 3 to 4 cm,in thickness,Average weight is,about 150 to 250 g,lies in the shelter,of the 9th to 11th,rib at the left side,of the abdominal,cavity,Anatomy,A pancreas,B spleen,C duodenum,5 Hepatic portal vein,8 celiac artery (trunk ),9 superior mesenteric artery,13 superior mesenteric artery,The spleen receives its arterial supply from the,splenic artery, which originates in the celiac axis.,After its origin, the splenic artery courses,along the superior edge of the pancreas,with multiple branches into the pancreatic,parenchyma. The artery then,g ives off several branches into,the spleen, the first being the,superior polar artery. There are,other arterial vessels to the,spleen from the left,gastroepiploic artery,and the short gastric,artery.,The splenic veins follow the arterial,distribution closely, and the main,splenic vein emerges from,the spleen following a course,to join the superior mesenteric,vein, forming the portal vein.,Functions of the Spleen,Circulation through the spleen is about 150 to 200 ml/min,or about 5% of the cardiac output.,The spleen has traditionally been ascribed four functions :,filtration,immunological,reservoir,hematopoietic,Filtration,abnormal or senescent red blood cells ,particulate antigens such as microorganisms,or antigen-antibody complexes.,Immunological,trapping of antigens,homing of lymphocytes,antibodyand lymphokine production,microphage activation,immunoglobulin and antibody synthesis ,affects the capability of cellular,populations in other lymphoid organs,Reservoir,Hematopoietic,Spleen harbors about one-third,of the total platelet mass and,a large number of granulocytes.,The hematopoietic functions are,minimal in humans and much more,prominent in other species.,Pathological Conditions of the Spleen,Splenic Rupture,Benign Lesions of the Spleen,Maligant Lesions of Spleen,Splenic Rupture,The spleen can rupture from three underlying causes:,trauma,spontaneous rupture,and pathological rupture.,Traumatic rupture of the spleen remains the,most frequent indications for splenectomy.,Pathologicalcauses of splenic rupture include,infiltration of the spleen by reactive lymphoid,cells or by neoplastic cells.,Most cases attributed to spontaneous rupture,of the spleen are actually due to an undiagnosed,pathological process.,Conditions associated with defective or absent splenic,function are grouped together as being conditions of,hyposplenism,. Those conditions are characterized by,the presence of,Howell-Jolly,bodies,in the peripheral,circulation. Conditions associated with,hypersplenism,remain the most frequent indication for elective,splenectomy ,these can be divided into those conditions,in which the spleen is normal but increased destruction,of abnormal blood elements causes,hypersplenism,and those in which there is a primary disorder of,the spleen that results in increased destruction of,abnormal blood cells.( Table 1).,Pathological Conditions of the Spleen,TABLE 1 Disorders Associated With Hypersplenism,1.Disorders associated with sequestration of abnormal blood cells in an intrinsically normal spleen.,A. Congenital disorders of erythrocytes,1. Hereditary spherocytosis,2. Hereditary elliptocytosis,3. Hemoglobinopathies,B. Acquired disorders of erythrocytes,1.Autoimmune hemolytic anemia,2.Parasitie disease(e.g.,malaria,babesiosis),C. Autoimmune thrombocytopenia,D. Autoimmune neutropenia,2. Disorders of spleen resulting in sequestration of normal blood cells,A. Disorders of cordal macrophages: Banti,s syndrome, storage,diseases, parasitie diseases(e.g.,kala-azar),Langerhan,s cells,histiocytosis, malignant histiocytosis,B. Infiltrative disorders:leukemias,lymphomas,plasma cell,dyscrasias, myeloid metastatic carcinnoma,C. Vascular abnormalities,D. Splenic cysts,E. Hamartomas,3. Miscellaneous conditions,A. Hyperthyroidism,B. Hypogammaglobulinemia,C. Progressive multifocal leukoencephalopathy,Source: Reiman (1997).3,Benign Lesions of the Spleen,Hemangioma,Lymphangioma,Peliosis,Hemangioendothelioma,Hamartomas,Other Benign Lesions,Nonparasitic Cysts,Parasitic Cysts,Hemangioma,This is the most common,benign primary neoplasm of,the spleen and can present with,splenomegaly,Lesions can be solitary or,multiple, and are usually,blue-red, well-circumscribed,nodules.,Microscopically,they usually,appear as endothelium-lined,spaces, and are known as,cavernous hemangiomas.,Treatment of these lesions,is usually splenectomy,Benign Lesions of the Spleen,Gross images:,It weighed 425 grams and measured,15 x 9 x 7 cm.A splenectomy was performed.,Micro images:representative section of tumor,Lymphangioma,These lesions are less common than hemangiomas,and are usually subcapsular, appearing as soft,compressible, multicystic lesions on the,splenic surface.,When large, they present with,splenomegaly as an indication.,There are case reports of patients,presenting with hypersplenic syndromes,consumptive coagulopathy, and,even portal hypertensionwith,these lesions.,Benign Lesions of the Spleen,Peliosis,These rare lesions bear a superficial resemblance to,vascular neoplasms of the spleen.,They consist of blood-filled cysts distributed,in patches or diffusely, and can result in splenomegaly.,Intraperitioneal hemorrhage can,result from the rupture of these lesions.,Benign Lesions of the Spleen,Hemangioendothelioma,These rare lesions is thought to be intermediate between,hemangioma and angiosarcoma.,They usually contain cellular atypia, differentiating,them from hemangiomas.,These lesions may present with splenomegaly or rupture,and should suggest the possibility of a malignabt vascular,neoplasm.,Hamartomas,These are focal developmental abnormalities within the,normal spleen, rather than being true neoplasms.,They consist of normal cellular elements in disarray,and are usually found incidentally,Benign Lesions of the Spleen,Maligant Lesions of Spleen,There are many malignancies that affect the spleen.,. Lymphoproliferative disorders,a. Non-Hodgkin,s lymphoma,b. Hodgkin,s disease,c. Chronic lymphocytic leukemia,d. Hairy cell leukemia,e. plasmacytoma,f. Waldenstrm,s macroglobulinemia,.,Myeloproliferative disorders,a. Chronic myelogenous leukemia,b. polycythemia vera,c. Myelofibrosis (agnogenic myeloid metaplasia),d. Essential thrombocythemia,.Vascular tumors,a. Hemangiosarcoma,b. Lymphangiosarcoma,. Metastatic tumors: breast,lung,melanoma,etc,.Other lesions,a. Sarcoma: fibrosarcoma, leiomyocarcoma, Kaposi,s sarcoma,Source: Adapted from Giles and Lim(1997). 7,Maligant Lesions of Spleen,Non-Hodgkin,s Lymphoma,Non-Hodgkin,s lymphoma is a diverse,group of disease with a wide range of,biological behaviors.,They may be very aggressive and rapidly,fatal, or may behave as one of the most,indolent and well-tolerated malignancies,afflicting man.,The role of the surgeon in Non-Hodgkin,s,lymphoma is usually limited to the biopsy of,a single peripheral lymph node to establish,a tissue diagnosis.,Splenectomy for Non-hodgkins lymphomas,􀂅,Symptomatic splenomegaly,􀂅,NHL confined to the spleen or with,prominent splenic involvement,Non-Hodgkin,s lymphoma are systemic,disease at the time of diagnosis, and require,the use of systemic therapy (e.g., chemotherapy),rather than regional therapy (e.g., radiation),for treatment.,Hodgkin,s disease,Hodgkin,s Lymphoma usually originates,in a single nodal group and predictably,proceeds in a stepwise progression from,one contiguous node group to the next.,Below the diaphragm, the spleen becomes,involved by Hodgkin,s Lymphoma,before proceeding along the periaortic,lymph nodes to the iliac and inguinal,nodal basins.,Historically, staging laparotomy with,splenectomy were essential guides to,treatment,Improvement in imaging and chemotherapy,have minimized the role of the surgeon,Chronic lymphocytic Leukemia (CLL),This is the most common of the chronic,leukemias, usually found in patients over,60 years of age.,It is usually of B-cell lineage and is,characterized by an accumulation of,incompetent lymphocytes.,CLL is incurable, but it is managed with,a variety of chemotherapeutic agents and,sometimes splenectomy.,Splenectomy is indicated in those,patients who progress despite chemotherapy.,Hairy Cell Leukemia,This is a rare lymphoproliferative,disorder that affects middle-aged men,It present with pancytopenia and,splenomegaly and is characterized,by the identification of “hairy cell”,in the peripheral circulation.,Splenomegaly is thus reserved for,patients who fail to respond to systemic,chemotherapy or who have massive,symptomatic splenomegaly.,Myeloproliferative Disorders,This disease include,chronic myelogenous leukemia,(CML),myelofibrosis,polycythemia vera,and essential thrombocythemia.,The role of splenectomy remains,controversial in this disease,.,Micro images: CML,myelofibrosis,polycythemia vera,essential thrombocythemia,Hemangiosarcoma,This is a rare,primary tumor of,the spleen in humans.,Treatment is,surgical, and no,effective adjuvant,therapies have been,identified.,Indications for Splenectomy,There are two surgical procedures performed,in reference to the spleen:,partial splenectomy,splenectomy.,A splenectomy can be conducted by,conventional open technique (OS) or,by laparoscopic means (LS).,Indications for Splenectomy,Splenectomy for Trauma,Management of Splenic,Injuries In Children,Management of Splenic,Injuries In Adults,Splenectomy for,Hematological Disorders,Hereditary Spherocytosis,Thalassemia,Sickle Cell Disease,Idiopathic Autoimmune Hemolytic,Anemia,Idiopathic Thrombocytopenia,Purpuma (ITP),Thrombotic Thrombocytopenia,Purpuma (TTP),Splenectomy for Trauma,The spleen is the organ most commonly injured in blunt,abdominal trauma, and thus the majority of splenectomies,are performed for trauma.,Splenic injury is often suspected,in the injured patients on the basis,of mechanism of injury and the,presence of associated injuries,such as left lower rib fractures.,Some patients undergo CT scan,of the abdomen and reveal injuries,such as those seen in Figure 1.,Figure 1.,Once splenic injury is identified, there are three options:,nonoperative management,splenic salvage (repair of the injury or partial,splenectomy),or splenectomy.,In these critically injured patients with multiple,intraabdominal injuries, splenectomy is the only,procedure to be considered.,TABLE 3 Grading of Traumatic Splenic Injuries, Hematoma Subcapsular, nonexpanding,10% surface,Laceration Capsular tear, nonexpanding,1cm parenchymal depth, Hematoma Subcapsular, nonexpanding,10%-50% surface area,Laceration Capsular tear, active bleeding,1-3cm,not involving a,trabecular vessel, Hematoma Subcapsular,50% surface area or expanding,ruptured subcapsular hematoma with active bleeding,intraparenchymal hematoma,2cm or expanding,Laceration 3cm parenchymal depth or involving trabecular,vessels, Hematoma Ruptured intraparenchymal hematoma with active bleeding,Laceration Laceration involving segmental or hilar vessel with,major devascularization(25%), Hematoma Completely shattered spleen,Vascular Hilar vascular injury with devascularized spleen,Source: Adapted from Lipshy et al.(1996).20,Splenic injuries are graded by severity (Table 3).,The splenic management of a patient with a splenic,injury is guided by the overall stability of the injured,patient, mechanism of injury, age, interval from time,of injury, associated injuries, and preexisting medical,conditions.,In a recent series of adults with splenic injuries,18% were treated nonoperatively, 22% underwent,splenorrhaphy, and 60% underwent splenectomy.,Management of Splenic Injuries In Children,The nonoperative management of splenic injury has been,applied primarily in children.,Guidelines for the nonoperative management of splenic,injuries in children include,documentation of splenic injury by imaging studies,admission to the ICU with close observation,hemodynamic stability ,serial hematocrit determination,absence of other intraabdominal injuries,transfusion requirements less than 50% of the blood,volume,and absence of neurottrauma,Management of Splenic Injuries In Adults,The nonoperative management of splenic injuries in adults,is less established as a standard than in children.,Patients are considered candidates for nonoperative management,by meeting criteria such as:,hemodynamic stability,minimum transfusion requirement,absence of associated intraabdominal injury,stable defect on repeat imaging .,an ability to perform reliable serial abdominal examinations.,Grade I to II injuries (capsular,avulsions and superficial parenchymal,fractures) are managed by topical,hemostatic agents.The argon beam,coagulator may be helpful in the,management of these lesions. Mattress,sutures over Teflon pledgets mays be,useful to close deeper wounds.,Grade III and IV splenic injury requires complete,mobilization of spleen to expose the hilum. Division,of the short gastric vessels is required. Partial splenectomy,may be indicated.,Splenectomy for Hematological Disorders,TABLE 4 Indications for Elective Splenectomy.,ITP(idiopathic thrombocytopenia purpura),Hereditary spherocytosis,Autoimmune hemolytic anemia,Staging for Hodgkin,s disease,Lymphoma,Thrombocytopenic thrombotic purpura,AIDS-related thrombocytopenia,Leukemia,Splenic abscess,Gaucher,s disease,Myelofibrosis,Splenic infarct,Hereditary Spherocytosis,􀂅,Autosomal dominant fashion,􀂅,Most common hemolytic anemia for which,splenectomy is advised,􀂅,Defective erythrocyte membrane causes,trapping and disintegration within the,spleen,􀂅,Presents with anemia, reticulocytosis,jaundice, and splenomegaly,􀂅,Diagnosis made by peripheral blood smear,􀂅,Splenectomy is the only therapeutic,modality (wait until age 4 to 6),Splenectomy for Hematological Disorders,Thalassemia,􀂅􀂅,Autosomal dominant transmission,􀂅􀂅,Defect in the synthesis rate of hemoglobin,􀂅􀂅,Thalassemia major (homozygous) presents,with pallor, retarded body growth, enlarged,head, and intractable ulcers,􀂅􀂅,Diagnosis made by nucleated RBCs (target,cells) in smear,􀂅􀂅,Splenectomy reserved for patients with,markedly symptomatic splenomegaly, painful,splenic infarction, and increased transfusion,requirements,􀂅􀂅,Greater risk of post-splenectomy sepsis,Splenectomy for Hematological Disorders,Sickle Cell Disease,􀂅,􀂅􀂅,Due to homozygous inheritance of HbS,􀂅,Single amino-acid substitution of valine for,glutamic acid,􀂅,Spleen commonly enlarged during the first,decade of life but then undergoes,progressive atrophy due to repeated attacks,of vaso-occlusion and infarction,􀂅,􀂅,In general, splenectomy should be avoided,in patients with SCD,􀂄,􀂅,Already immunocompromized,Splenectomy for Hematological Disorders,Idiopathic Autoimmune Hemolytic Anemia,This disease is characterized by hemolysis of normal,erythrocytes after exposure to circulating antibodies.,The spleen serves as a source of,antibody in this process.,The initial therapy is steroid administration ,Reserving splenectomy for patients,in whom steroids are ineffective or contraindicated,.,Splenectomy for Hematological Disorders,Idiopathic Thrombocytopenia Purpuma (ITP),􀂅,Most common hematologic indication,for splenectomy,􀂅,Spleen is the source of circulating,antiplatelet IgG,􀂅,Diagnosis made by thrombocytopenia,with normal bone marrow,􀂅,Usually an isolated phenomenon,􀂅,Patients present with ecchymosis and,purpura and at times there is excessive,bleeding from the gums,vaginal bleeding,gastrointestinal bleeding, and hematuria,􀂅,Platelet count characteristically less,than 50,000/mm,3,First line of treatment medical:,􀂄,Steroids ;IgG ; Plasmapheresis,Medical treatment only curative in 15% of adults,Cure rates up to 87% reported with splenectomy,Splenectomy for Hematological Disorders,Thrombotic Thrombocytopenia Purpuma (TTP),􀂅,Increase of subendothelial,collagen in the arterioles and,capillaries causing diffuse,platelet trapping,􀂅,Manifested by,thrombocytopenia, hemolytic,anemia, fever, neurologic,manifestations, and renal,failure,􀂅,Primarily treated with high,volume plasmapheresis (80 to,90% survival) ,F,irst-line therapy,remains medical,.,Splenectomy reserved for,non-responders,Splenectomy for Hematological Disorders,Operative Approach to the spleen,Patient Preparation,Open Splenectomy,Partial Splenectomy,Accessory Splenic Tissue,Incidental Splenectomy,Laparoscopic Splenectomy,Patient Preparation,Patients should be immunized against Pneumococcus,Haemophilus influenza B, and Meningococcus at least,2 weeks before operation .,Patients must be given a thorough discussion of,overwhelming postsplenectomy infection before the,procedure.,The technique has remained,largely unchanged for many years,.,The patients is placed on the,operating table in the supine,position,.,The incision used is dependent on the,performed with facility through a,midline incision or a left subcostal,incision.,The splenic artery can be managed,in several ways.,After removal of the spleen, drains,are not usually required, but when,desired, closed suction drains are,employed.,Open Splenectomy,Operative Approach to the spleen,Laparoscopic Splenectomy,LS has become the preferred,surgical technique for ITP and,other diseases with normal,spleen size.,The technique of laparoscopic,splenectomy was first described,in 1992 and has become a,well-accepted procedure.,Operative Approach to the spleen,Strict lateral position of the patient for,laparoscopic splenectomy. The table is,angulated, giving forced lateral flexion,of the patient to open the costophrenic,space. Trocars are inserted along the left,costal margin more posteriorly. The spleen,is hanged by its peritoneal attachments.,The numbered lines show the position of,laparoscopic ports.,The lateral position offers excellent,exposure of the hilum to facilitate,dissection and vessel ligation.,Operative Approach to the spleen,Increasing operative experience,and technical refinements have,produced good results relative,to open splenectomy (OS) in terms,of outcome, patient discomfort,length of hospitalization, and costs.,Wound problems, infections, and,pulmonary complications, which,are particularly troublesome with,conventional splenectomy,techniques, may be avoided,with LS.,Operative Approach to the spleen,Partial Splenectomy,The principal indication f