Appendiceal neuroma (obliterative appendicitis / neurogenic appendicopathy) is a benign condition characterized by proliferation of neural elements (Schwann cells, nerve fibers, ganglion cells) in the appendiceal wall. It most commonly develops in the post-appendectomy stump or in the setting of chronic inflammation. Incidentally detected in 0.5-5% of appendectomy specimens. Clinically usually asymptomatic; however, post-appendectomy stump neuroma may present with right lower quadrant pain (stump appendicitis-like presentation).
Age Range
30-65
Peak Age
45
Gender
Equal
Prevalence
Rare
Appendiceal neuroma develops from reactive, non-neoplastic proliferation of neural elements in the appendiceal wall. The pathophysiological mechanism involves two distinct pathways: (1) Chronic inflammation pathway — recurrent low-grade inflammation triggers reactive hyperplasia of nerve fibers in submucosal and myenteric plexuses; Schwann cells proliferate and neural plexuses expand. This process is also called 'obliterative appendicitis' because neural proliferation can partially or completely obliterate the appendiceal lumen. (2) Post-traumatic neuroma pathway — cut nerve endings after appendectomy show regenerative growth but form a disorganized neural tissue mass (traumatic neuroma). Schwann cells in neuroma tissue show characteristic MRI signal features — high signal on T2 (high water content), low-intermediate signal on T1, and enhancement (vascularized neural tissue). On CT, neuroma generally appears as a small soft tissue density nodule without specific features.
T2 hyperintense nodule at the cecal base/stump in a post-appendectomy patient — reflects high water content of neurogenic tissue. Has high predictive value for stump neuroma when combined with appendectomy history.
Small (<15 mm), well-defined, soft tissue density nodule at the cecal base/appendectomy stump. May show mild enhancement. Periappendiceal inflammatory changes are generally absent (chronic lesion).
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A __ mm soft tissue density nodule at the cecal base/appendectomy stump is observed, which should be evaluated for stump neuroma.
High signal intensity nodule at the cecal base/stump on T2-weighted sequences. High water content of neural tissue and myxoid stroma accounts for T2 hyperintensity. Split-fat sign (thin fat ring around neuromas) may be observed.
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A high signal intensity nodule at the cecal base is observed on T2-weighted sequences, compatible with neurogenic lesion (neuroma).
Progressive enhancement of the neuroma nodule on contrast-enhanced MRI. Mild enhancement in early phase, more pronounced enhancement in late phase. This enhancement pattern reflects the vascular structure and large extracellular space of neural tissue.
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Progressive enhancement is observed in the nodule on contrast-enhanced MRI, compatible with neurogenic lesion.
Small, hypoechoic, well-defined nodule at the cecal base/appendectomy stump on ultrasonography. May show homogeneous internal echo pattern and posterior acoustic enhancement (solid but homogeneous structure). No inflammatory changes in surrounding fat.
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A small, hypoechoic, well-defined nodule at the cecal base is observed, which should be evaluated for post-appendectomy neuroma.
Neuroma nodule shows isointense or mildly low signal intensity to muscle on T1-weighted sequences. Signal does not change on fat-suppressed T1 (no fat content).
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The nodule shows isointense signal to muscle on T1-weighted sequences.
Criteria
Regenerative growth of cut nerve endings after appendectomy. Localized neural tissue mass at the stump.
Distinct Features
Appendectomy history mandatory. Small nodule at stump location. Re-resection is curative if symptomatic.
Criteria
Diffuse neural proliferation in the appendiceal wall in the setting of chronic inflammation. Lumen partially or completely obliterated.
Distinct Features
Seen in intact appendix. Diffuse wall thickening, luminal narrowing. Incidentally detected — pathological diagnosis in appendectomy specimen.
Distinguishing Feature
Lymphoid hyperplasia shows homogeneous intermediate signal, T2 hyperintensity is not as pronounced as neuroma. Neuroma shows markedly high signal on T2 and split-fat sign.
Distinguishing Feature
Mucocele shows cystic dilatation and low-density mucinous content. Neuroma is a solid soft tissue density nodule without cystic component.
Distinguishing Feature
Lipoma shows negative density (-70 to -130 HU); neuroma shows soft tissue density (30-50 HU). On MRI, lipoma shows T1 high signal (fat), neuroma shows T1 low-intermediate signal.
Urgency
routineManagement
conservativeBiopsy
Not NeededFollow-up
12-monthAppendiceal neuroma is a benign condition that does not require treatment in most patients. Follow-up is sufficient for incidentally detected asymptomatic neuromas. Stump resection is curative for symptomatic stump neuroma (chronic right lower quadrant pain, stump appendicitis-like presentation). Malignancy risk is very low; however, carcinoid tumor should be considered in differential diagnosis — biopsy or surgical excision is recommended if CT/MR findings are indeterminate. Obliterative neurogenic appendicopathy is generally detected as an incidental pathological finding in appendectomy specimens and requires no additional treatment.
Appendiceal neuroma is a benign lesion that generally requires no treatment. Follow-up is not necessary when discovered incidentally. However, differentiation from carcinoid tumor is important. Surgical excision is curative in symptomatic cases (chronic right lower quadrant pain). Malignant transformation has not been reported.