Table 4.

Differential table for heterotaxy polysplenia (left isomerism) syndrome

Disorder	X-ray	Echocardiography	USG	CT	MRI
Heterotaxy (Situs ambiguous) Polysplenia (Left isomerism) Syndrome	Cardiac apex- left/right Aortic arch- left/right Dilated azygos vein Bilateral bilobed lungs Stomach – left/right	Cardiac apex- left/right Incomplete AV septal defect Normal relationship of great arteries Bilateral left atrial appendages	Multiple spleens- left/right Liver Right/Left/Midline Interrupted IVC Truncated pancreas Gut malrotation with SMV rotation sign	Cardiac apex-left/right Aortic arch- left/right Bilateral left atrial appendages Interrupted IVC with azygos/hemiazygos continuation Normal suprahepatic IVC Bilateral bilobed lungs Bilateral hyparterial bronchi Normal relationship of IVC and aorta in abdomen Multiple splenules Stomach- left/right Liver- right/left/midline Gut malrotation with SMV rotation sign Short truncated pancreas Preduodenal portal vein	Cardiac apex-left/right Aortic arch- left/right Bilateral left atrial appendages Interrupted IVC with azygos/hemiazygos continuation Normal suprahepatic IVC Bilateral hyparterial bronchi Normal relationship of IVC and aorta in abdomen Multiple splenules Stomach- left/right Liver- right/left/midline Gut malrotation with SMV rotation sign Short truncated pancreas Preduodenal portal vein
Heterotaxy (Situs ambiguous) Asplenia (Right isomerism) Syndrome	Cardiac apex- Right/Left/Midline Aortic arch- right/left Bilateral trilobed lungs Stomach- right/left	Cardiac apex- right/left/midline Bilateral right atrial appendages ASD Common atrioventricular valve Transposition of great arteries Pulmonary stenosis/atresia Bilateral SVC TAPVC IVC & aorta on same side of spine	Absent spleen Stomach- midline/right/left Symmetrical and midline liver midline gall bladder IVC and aorta on the same side of spine in abdomen Gut malrotation Truncated pancreas	Cardiac apex- right/left/midline Aortic arch- right/left Transposition of great arteries (TGA) Persistent left SVC Total Anomalous Pulmonary Venous Connection Pulmonary atresia/stenosis Bilateral eparterial bronchi Bilateral trilobed lungs Absent spleen Symmetrical and midline liver Midline gall bladder Right sided stomach Gut malrotation Truncated pancreas	Cardiac apex- right/left/midline Aortic arch- right/left Transposition of great arteries (TGA) Persistent left SVC Total Anomalous Pulmonary Venous Connection Pulmonary atresia/stenosis Bilateral eparterial bronchi Absent spleen Symmetrical and midline liver Midline gall bladder Right sided stomach Gut malrotation Truncated pancreas
Situs inversus totalis	Cardiac apex- right (Dextrocardia) Right Aortic arch Bilobed right and trilobed left lung Dextrogastria	Cardiac apex- right (Dextrocardia) Right atrium and ventricle on left side Left atrium and ventricle on right side Corrected transposition of great arteries Left IVC and right sided aorta	Right side spleen Right sided stomach (Dextrogastria) Left sided liver and Left sided gall bladder Left IVC and right sided aorta	Cardiac apex-right (Dextrocardia) Right aortic arch Corrected transposition of great arteries Right sided aorta and left IVC Right hyparterial & left eparterial bronchus Bilobed right and trilobed left lung Right side spleen Left side liver Left side gall bladder Right side stomach	Cardiac apex-right (Dextrocardia) Right aortic arch Corrected transposition of great arteries Right sided aorta and left IVC Right hyparterial & left eparterial bronchus Right side spleen Left side liver Left side gall bladder Right side stomach