accessory spleen

(redirected from splenule)

spleen

 [splēn]
a large glandlike but ductless organ in the upper part of the abdominal cavity on the left side, lateral to the cardiac end of the stomach. Called also lien. adj., adj splen´ic. It is the largest collection of reticuloendothelial cells in the body and is composed of spongelike tissue of two types: red pulp, which is the dark reddish brown substance filling the interspaces of the sinuses of the spleen, and white pulp, which consists of sheaths of lymphatic tissue surrounding the arteries of the spleen. It is enclosed in a dense capsule. In a normal adult the spleen is about 12.5 cm long and weighs about 140 to 210 g. After gastric digestion and in the presence of disease the spleen enlarges.



During fetal life the spleen and liver produce erythrocytes, but after birth that function is taken over by the bone marrow. However, if there is bone marrow failure, the spleen may again produce erythrocytes. In the normal adult the spleen is a reservoir for blood, and contains a high concentration of erythrocytes. In times of exertion, emotional stress, pregnancy, severe bleeding, carbon monoxide poisoning, or other occasions when the oxygen content of the blood must be increased, the spleen contracts rhythmically to release its store of erythrocytes into the bloodstream.

The spleen also acts to help keep the blood free of unwanted substances, including wastes and infecting organisms. The blood is delivered to it by the splenic artery, and passes through smaller branch arteries into a network of channels lined with leukocytes known as phagocytes (see reticuloendothelial system). These clear the blood of old erythrocytes, damaged cells, parasites, and other toxic or foreign substances. Hemoglobin from the removed red cells is temporarily stored.
accessory spleen a small mass of tissue elsewhere in the body, histologically and functionally identical with that composing the normal spleen.

ac·ces·so·ry spleen

[TA]
one of the small globular masses of splenic tissue occasionally found in the region of the spleen, in one of the peritoneal folds or elsewhere.

accessory spleen

splen accessorius Any of a number of small aggregates or masses of encapsulated splenic tissue located adjacent to the spleen or along the gastrosplenic ligament. See Spleen.

ac·ces·so·ry spleen

(ak-ses'ŏr-ē splēn) [TA]
One of the small globular masses of splenic tissue occasionally found in the region of the spleen, in one of the peritoneal folds, or elsewhere.
Synonym(s): lien accessorius.
References in periodicals archive ?
This mass had been seen on a chest PE with contrast study 12 years prior and had similar contrast enhancement patterns and Hounsfield unit values as the spleen, compatible with a splenule (Figures 3A, 3B).
Infarcted splenule. Differential diagnoses: neoplasm, tuberculoma, infectious abscess.
In this case, CT was used to diagnose an infarcted splenule. While rare, it is important to know the radiological and clinical signs in order to keep a high index of suspicion for infarcted splenule given the correct clinical scenario in order to prevent unnecessary surgery and facilitate correct, conservative treatment.
Splenules, or accessory spleens, are congenital foci of normal splenic tissue that are separate from the main body of the spleen.
(7) These unusual imaging features led those involved to consider rarer extratesticular lesions such as polyorchism with malignant degeneration, posttraumatic extra-abdominal splenule implantation, and lymphoma.
Mimics: Multiple lesions can mimic primary pancreatic masses, such as duodenal diverticula, accessory splenules in the pancreatic tail, retroperitoneal masses, or masses arising exophytically from adjacent organs (Figure 9).
The presence of accessory splenules may arise within the substance of solid organs, notably the pancreas [10].
Accessory spleen, in other words supernumerary spleens, splenunculi, or splenules, results from the failure of fusion of the primordial splenic buds in the dorsal mesogastrium during the fifth week of fetal life.
By demonstrating uptake of 99m-Tc sulphur colloid or 99m-Tc-labelled heat-denatured erythrocytes within the splenules a diagnosis can confidently be made (10).
Computed tomography (CT) showed paraesophageal fluid and varices, liver cirrhosis, splenectomy and multiple splenules. There is a dilated upper and mid esophagus with air fluid level, paraesophageal fluid and varices; mid to lower esophagus was dilated with fluid contrast level to the distal esophagus, approaching the gastroesophageal junction.
A diagnosis can be made by demonstrating uptake of 99m-Tc sulphur colloid or 99m-Tc-labeled heat-denatured erythrocytes within the splenules, (2) although the latter has higher specificity.
(38,39) Splenic activity is usually less than liver on FDG-PET, and CT can be of particular help with splenules that can cause some confusion on PET imaging alone.