SUMMARY OF SPLEEN IMAGING THE SPLEEN Imaging Techniques

SUMMARY OF SPLEEN IMAGING THE SPLEEN Imaging Techniques �CTand. US: major techniques. �Radioisotopes: confirmthepresenceoffunctioningsplenic tissue. �MR: CTismoreimportant Anatomy Functions: Formation. Fetus. Blood-Sequestration. Aged. Cells– Reservoir. R. B. Cs Site: leftupperquadrant/belowthediaphragm/, posterior&lateraltothe stomach. Surfaces: 2 surfaces/ Diaphragmatic smoothandconvex, - Visceral: Haveconcavitiesforthestomach, kidney, colon, andpancreas. Size: Averagedimensions CHILD (in adults) 6 + 1/3 Age in Years Length: 12 cm, ADULT Splenic / Renal index not > 1. 2 Width: 7 cm, 120: 480 Cm 3 Thickness: 3 to 4 cm. length x width x thickess Blood supply: - Thesplenicarteryandvein coursethroughthepancreastothesplenichilum, divideinto multiple branches. - Splenicarteries: areendarteries(noanastomosesorcollaterals) Occlusionofthesplenic. A. or its branches infarction. - Variableratesof bloodflowthroughsplenicparenchyma Heterogenous. Enhance "Transientpseudomasses"@earlyarterial phaseboth. CTand. MR. Imaging: - Onallimagingstudies, homogeneousappearance. CECTand. MR lesionsarebestdemonstrated. Onnoncontrast. CT, spleendensityislessthanorequalnormalliver. On. MR: intensity o T 1 WIs islowerthanhepaticparenchyma. o T 2 WIs higherthanliverparenchymaon. By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING - Arterialphase irregulardefectsin parenchymalenhancement. - Oneor 2 minuteslater, the entirespleenishomogeneouslyenhancedonboth. CTand. MR. - Lobulationsandclefts: common/ mustnotbemistakenformassesorsplenicfractures. Accessory spleens 10%to 16%ofnormalindividuals 1 to 3 cm, Roundmasses, Singleor multiple. Sameasnormalsplenicparenchyma. Usuallynearthesplenichilum. ® If. Near. Tailof. Pancreas Misdiagnosed aspancreaticmass Wandering spleen Laxityofthesplenic ligaments spleentobewanderanywherein theabdominal cavity. o (+/-abnormalitiesofintestinal rotation, ) C. P. : mostcause nosymptoms. / Mass/ pain Torsion Complication: Torsion Splenosis Def: multipleimplantsofectopicsplenictissue, mayoccuraftertraumaticsplenicrupture. Pathology: Splenictissuecanimplantanywherein the abdominalcavity , or(eveninthethoraxif thediaphragmhasbeenruptured). o Splenosiscomplicates 40%to 60%ofsplenicinjuries. o Usuallymultiple&varyin sizeandshape. By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING o Thetissuefragmentsenlargeovertime maysimulateperitonealmetastases. Aftersplenectomy, seedingofsplenic tissuerupture remainingaccessoryspleensor splenules mayenlargeandresumethefunctionoftheresected spleen. Howell-Jollybodies: bitsofnuclearmaterialseenin RBCsafter spleenectomy. Disappearanceofthese. Howell-Jollybodies signofsplenic regeneration. ® Imagingstudies singleormultiplespleen-likemassesin theabdominalcavity+historyof splenectomy. Polysplenia Rare Multiplesmallspleens, usuallylocatedin theright abdomen+situs ambiguous. Mostpatientsalsohavecardiovascularanomalies. Asplenia (Ivemark syndrome) Mostlydiebefore 1 yearofage Congenitalabsenceofthe spleen. Associatedwith: bilateralright-sidedness+midlineliver+bilateralthree-lobedlungs. Majorcardiacanomalies in 50%ofcases. By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING Congestive spleniclength>13 cm Splenome galy Myeloproliferative -Portalhypertension(50%ofcases) -Portalveinthrombosis Infiltrative -Systemiclupus erythematosus -Amyloidosis -Gaucher disease Infection -Lymphoma(30%ofcases) Malaria (universalin endemicareas) -Leukemia Schistosomiasis(endemicareas) -Polycythemia Infectious mononucleosis Subacutebacterial endocarditis -purpura Idiopathic AIDS thrombocytopenia -Sicklecelldisease(in infants) IVdrug abuse - spherocytosis -Thalassemia major CHILD - Hereditary -Myelofibrosis ) 6 + 1/3 Age in Years ) ADULT Splenic / Renal index not > 1. 2 length x width x thickess Diagnosis: 120: 480 MR nosignificantbenefitin thedifferentialdiagnosisofsplenomegaly. Mildtomoderatesplenomegalyisseenwith portalhypertension, AIDS, storagediseases, collagen vasculardisorders, andinfection. More marked splenomegaly usually associated with lymphoma, leukemia, infectious mononucleosis, hemolyticanemia, andmyelofibrosis. Portosystemiccollateral vessels - AWV=abdominalwallvarices CV=coronaryvenouscollateral vessels EV=esophageal varices GRV=gastrorenal shunt IMV=inferior mesentericvein LPV=left portalvein LRV=leftrenal vein MV=mesentericvarices OMV=omental varices PEV=Paraesophagealvarices PSV=perisplenic varices PUV=Paraumbilicalcollateral vessels PV=portal vein RGV=retro-gastric varices RPPV=retroperitoneal-Para vertebral varices SMV=superiormesentericvein SRV=splenorenal shunt SV=splenic vein. Dilatedporto-systemiccollaterals In portalhypertension Sever. Paraesophagealvarices By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING CYSTIC LESIONS OF THE SPLEEN Usuallydiscoveredaccidentally Largeorcomplicatedcystsproducesymptoms Complications: rupture, infection , hemorrhage Splenic Cysts Primary True. Epithelial Lining Parasetic"Hydatid" Cong. Simple Epidermoid 5% Multiple. Simple. Hepatic&splenic Cysts Secondary No. Epithelial. Lining"False" Post. Traumatic(80%) Infecti ous Infarc Hydatid Cyst tion Abscess "Enh. Margins&Airless common" Multipple. Fungul. Abscess "Immunocompromised" Splenic. Sarcoidosis. D. D. Multiple. Splenic. Calcifications (TBor. Histoplasmosis) MULTIPLE SMALL CYSTS LIVER SPLEEN Metastases Fungal Abcesses Abcess Simple By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING SPLENIC TRAUMA (Blunt/ Penetrating) Commonest. Abdominalorgantobeinjured. +/-Otherorgans. Injury CT Best. Modalityto. Diagnose. "accuracy 98%" Staged by of laceration 3 I <1 Rul cme Superficial subcapsular hematoma II I: II Heal 1: 3 cm in Deeplaceration 4 m subcapsular hematoma III >3 cm Deeplaceration subcapsular hematoma III " "6 m IV Fragmentation>3 pieces Subcapsular. Hematoma Shuttered Spleen no enhancement Deep. Laceration SPLENIC INFARCTION Singleormultiplewedgeshapedhypodensitiesbasedtothespleniccapsule+/-Ca Causesinclude: o Embolicincardiovasculardiseases (endocarditis, AF, Localthrombosis( o splenic. Torsion wanderingspleen-o pancreatitis o AIDS, o sicklecell disease (when. Chronic Fibrosis Volumeloss) By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING SICKLE CELL DISEASE Hereditary(autosomalrecessive) formationofabnormalhaemoglobin(haemoglobinopathy) Abnormalshape. RBCs"Sicklelike" Aggregationin Bloodvessel �Atsmallarteriole Infarction �Atsplenicvain bloodtrapping SQUESTRATION / RUPTURE �Atsplenic. A. AUTO-SPLENECTOMY �Abnormaliron. Accumulation"Haemosedrin" 2 ry Haemosedrosis Infarction Peripheralwedgeshape Hypodensity SQUESTRATIO N Infantorchild Enlargedheterogenous spleen+/- Rupture AUTOSPLENECTOMY Totalgradual. Infarction Smallcalcefiedspleen 2 ry. Haemosedrosis ironoverloaddisorder the accumulationofhemosiderin "Diffudelossofsignalin. MRI& inceasedensityin. CT. By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING Gamna gandy bodies Only seen in MRI Multiplesmall. Focioflowsignal =Organizingfociofhaemorhage Seen 10%ofportalhypertension/ Notrelatedtospleen size. Onlyseenby. MRI"Notby. CT" NEOPLASMS OF THE SPLEEN Any solid lesion in the spleen is considered malignancy until proved Normal spleen imaging Not exclude Metastasis Hemangioma -Commonestbening (14%) Lipoma Welldefined– Fat density Primary: Rare Secondary: Uncommon Angiosarcoma Massheterogenous/Rare–Primary Mayinvolveholespleen Hemangiomatosis Mets LYMPHOMA The most common malignant lesion of the spleen Splenic involvement in HD = 27% / NHL =35% Lymphoma"4 patterns" Uncommon Hematogenousspread Breast, lung, ovary, stomach, melanoma *Calcificationisrare By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING Spotted spleen Multiplelowattenuationnodules Uncommon. Finding/ Butcommonin Immunosupresed"Infectious" Neoplasm Infections - Lymphoma"coomonest" - Fungul - Metastases - Mycobacterial - Hemangioma - Parasetic Sarcoid CASES Splenic TB Wandering. Spleen Hydatid. Cyst Massive. Infarction Auto-splenectomy Splenic. Cysts Lymphoma Polysplenia– Situs Inversus Spotted Spleen Portal Hypertension Leiomyosarcoma &Livermets Mets Angiosarcoma Gamna. Gandy. Bodies By Ahmad Mokhtar Abodahab

SUMMARY OF SPLEEN IMAGING Sources Fundmentals Sec VII -CHAPTER 28 – Primer of Diagnostic radiology 6 th Lecture of Prof. Mamdouh Mahfouz https: //radiopaedia. org By Ahmad Mokhtar Abodahab 7 July 2018