Improving diagnosis of atraumatic splenic lesions, part I: nonneoplastic lesions

Acoustic Radiation Force Impulse (ARFI) Elastography of Focal Splenic Lesions: Feasibility and Diagnostic Potential

PURPOSE

Nontraumatic focal splenic lesions (FSL) are rare, and the need for tissue diagnosis must be weighed against the very high risk of bleeding after a splenic biopsy. The aim of this study was to explore the feasibility and diagnostic potential of acoustic radiation force impulse (ARFI) elastography as a noninvasive method for different benign and malignant FSLs. No human studies on the elastographic characteristics of FSL exist.

METHODS

This was a retrospective analysis of 34 patients with FSLs, who underwent abdominal B-mode ultrasound (B-US), contrast-enhanced ultrasound (CEUS), and standardized ARFI examinations between October 2021 and December 2022 at our university hospital. The inclusion criteria were: (i) FSL size ≥ 1 cm; (ii) 10 valid ARFI measurements of the FSL, as well as of the normal splenic parenchyma (NSP) as an in vivo reference; and (iii) diagnostic confirmation of FSL etiology based on histological examination (8/34; 23.5%) or clinical evaluation, which included a clinical and sonographic follow-up (FU), CEUS morphology, and/or morphology on cross-sectional imaging (26/34; 76.5%). CEUS was performed on all patients and the FSLs were classified according to the current guidelines; cross-sectional imaging was available for 29/34 (85.3%). The mean FU duration was 25.8 ± 30.5 months. The mean ARFI velocity (MAV) of the FSL (MAVL), the NSP (MAVP), and the ratio of the MAVL to the MAVP (MAVL/P) were calculated and compared.

RESULTS

Of the 34 FSLs, 13 (38.2%) were malignant (mFSL) and 21 (61.8%) were benign (bFSL). The MAVL of all 34 FSLs (2.74 ± 0.71 m/s) was lower than the MAVP (3.20 ± 0.59 m/s), p = 0.009, with a mean MAVL/P ratio of 0.90 ± 0.34. No significant differences in the MAVL were observed between the mFSL (2.66 ± 0.67 m/s) and bFSL (2.79 ± 0.75 m/s). There were also no significant differences between the MAVP in patients with mFSL (3.24 ± 0.68 m/s) as compared to that in the patients with bFSL (3.18 ± 0.55 m/s). Likewise, the MAV L/P ratio did not differ between the mFSL (0.90 ± 0.41 m/s) and bFSL (0.90 ± 0.30 m/s) groups.

CONCLUSION

ARFI elastography is feasible in evaluating the stiffness of FSLs. The lesions' stiffness was lower than that of the NSP, regardless of the FSL etiology. However, differentiation between benign and malignant FSL with the help of this elastographic method does not appear possible. Larger prospective studies are needed to validate these findings.

Differential Diagnosis of Cystic Lesions of the Spleen: A Review of Clinical, Imaging and Pathological Findings

Cystic lesions of the spleen are being noticed with increased frequency as "incidentalomas" during imaging work-up for unrelated causes. As a group, these lesions encompass pure cystic and mixed cystic and solid, benign and malignant processes that in general require a tissue sample for definitive diagnosis. In this review, we will describe the differential diagnosis of cystic lesions of the spleen, highlighting key imaging, clinical and pathologic findings.

Differential Diagnosis of Abdominal Tuberculosis in the Adult-Literature Review

Tuberculosis (TB) is a public health issue that affects mostly, but not exclusively, developing countries. Abdominal TB is difficult to detect at first, with the incidence ranging from 10% to 30% of individuals with lung TB. Symptoms are non-specific, examinations can be misleading, and biomarkers commonly linked with other diseases can also make appropriate diagnosis difficult. As a background for this literature review, the method used was to look into the main characteristics and features of abdominal tuberculosis that could help with differentiation on the PubMed, Science Direct, and Academic Oxford Journals databases. The results were grouped into three categories: A. general features (the five forms of abdominal tuberculosis: wet and dry peritonitis, lymphadenopathy, lesions at the level of the cavitary organs, lesions at the level of the solid organs), B. different intra-abdominal organs and patterns of involvement (oesophageal, gastro-duodenal, jejunal, ileal, colorectal, hepatosplenic, and pancreatic TB with calcified lymphadenopathy, also with description of extraperitoneal forms), and C. special challenges of the differential diagnosis in abdominal TB (such as diagnostic overlap, the disease in transplant candidates and transplant recipients, and zoonotic TB). The study concluded that, particularly in endemic countries, any disease manifesting with peritonitis, lymphadenopathy, or lesions at the level of the intestines or solid organs should have workups and protocols applied that can confirm/dismiss the suspicion of abdominal tuberculosis.

Reappraisal of surgical decision-making in patients with splenic sclerosing angiomatoid nodular transformation: Case series and literature review

BACKGROUND

Many clinicians and surgeons are unfamiliar with the sclerosing angiomatoid nodular transformation (SANT), which is gaining recognition as a benign splenic tumor. We challenge that SANT is rare and whether surgical intervention could be avoided through critical imaging review.

AIM

To evaluate the incidence of SANT among splenic tumors and the decision-making process of SANT management.

METHODS

Twenty hospitalized patients who underwent splenectomy in 2018 and 2019 in a tertiary university hospital were retrospectively reviewed, and their data on imaging, diagnosis, surgical indications, and courses were recorded. All pathology results were confirmed by pathologist. Discriminative features differentiating SANT from other non-SANT splenic tumors were descriptively analyzed in this case series.

RESULTS

Fourteen out of 20 patients who underwent splenectomy had splenic tumors, including 3 SANTs (21% splenic tumors), 6 non-SANT benign lesions (43%), 2 metastatic tumors, and 3 lymphomas. Hypointensity on T2-weighted magnetic resonance imaging (MRI), spoke wheel enhancing pattern in contrasted computed tomography or MRI, and cold spot (low fluorodeoxyglucose uptake) in positron emission tomography (PET) scan helped establish the diagnosis of SANT. Lymphoma, presenting with a hot spot on the PET scan were differentiated from SANT. Surgical indications were reformatted for splenic tumors. Splenectomy need not be performed in patients with typical imaging features of SANT.

CONCLUSION

SANT is not a rare disease entity in clinical practice. Splenectomy should not be routinely indicated as the only management option for SANT with typical imaging features.

Focal splenic lesions: Imaging spectrum of diseases on CT, MRI and PET/CT

The spleen can be affected by a variety of diseases. Some of them are readily identified as variations of normal or benign diseases on imaging. However, for a substantial number of focal splenic abnormalities, the diagnosis can be difficult so that histopathologic analysis may be required for a definite diagnosis. In this review, the typical splenic abnormalities that can be diagnosed with imaging with a high degree of confidence are illustrated. The complementary role of computed tomography (CT), magnetic resonance imaging and positron emission tomography/CT that helps make a diagnostic approach is discussed. Finally, current applications and future trends of radiomics and artificial intelligence for the diagnosis of splenic diseases are addressed.

Iron-containing pathologies of the spleen: magnetic resonance imaging features with pathologic correlation

Systemic and non-systemic pathologies that involve iron deposition within the spleen have characteristic features on MRI due to the susceptibility properties of deposited iron, or hemosiderin. These lesions will have signal loss on longer echo sequences due to the T2* effect when evaluated with dual-echo gradient-echo sequences. The pathophysiology of systemic and localized iron sequestration disease processes can elucidate an underlying diagnosis based on these imaging features in conjunction with clinical information.

Calcified Splenic Lesions: Pattern Recognition Approach on CT With Pathologic Correlation

OBJECTIVE. Incidental splenic lesions, often found on CT images of the abdomen, may often be ignored or mischaracterized. Calcified splenic lesions are often presumed to be granulomas; however, understanding the broader differential diagnostic considerations can be useful. CONCLUSION. Determining the cause of splenic lesions is essential to guide appropriate management; the pattern of calcification together with other imaging and clinical findings can aid with differentiation.

Percutaneous Image-Guided Biopsy of the Spleen: Experience at a Single Tertiary Care Center

PURPOSE

The purpose of this study is to assess the complication rate of percutaneous image-guided biopsy of the spleen at our institution and to evaluate for variables associated with complication rate.

METHODS

This is a Research Ethics Board approved retrospective study of consecutive patients who underwent image-guided biopsy of the spleen at our institution from January 2010 to November 2019. Complications, imaging findings, and pathologic diagnosis were reviewed. Complications (major and minor) were classified per Society of Interventional Radiology Guidelines, and complication rate was calculated. Logistic regression was applied to determine factors associated with complications. Diagnostic yield was calculated.

RESULTS

In all, 55 patients (28 female) underwent splenic biopsy using ultrasound guidance. The most common indication was possible lymphoma in 41 (71.7%) patients followed by query metastasis 18 (31.5%) patients. Core biopsies (18 g/20 g) were done in 53 (92%) cases, and fine-needle aspiration (22 g) was performed in 4 (8%). The median number of samples collected was 4 (range: 2-9). The results were diagnostic in 54 cases (94.7%, 95% confidence interval [CI]: 88.7-100.0). There were 12 (21%, 95% CI: 10.1-31.9) patients with minor complications and 2 (3.5%, 95% CI: 0.0-8.4) with major complications (2 splenic bleeds requiring embolization, no splenectomy, or deaths). No variables (needle size, lesion size, and number of passes) were associated with complication rate.

CONCLUSION

Percutaneous image-guided biopsy of the spleen at a single tertiary care institution demonstrates major complication rate comparable to that in the literature with no variables associated with complication rate; there were no cases of splenectomy or death.

Asymptomatic Splenic Cysts in an Immunocompromised Patient: Should They Be Investigated

Splenic abscess is a rare disease that generally occurs in immunocompromised patients. It is difficult to distinguish between splenic abscesses and cysts using imaging studies, especially if they are asymptomatic. A 50-year-old asymptomatic man who had received steroid therapy for underlying rheumatoid arthritis was referred to a university hospital due to presence of several splenic cysts, with the largest being 3.5 cm in diameter. Percutaneous aspiration was performed, and fluid analysis showed cysts infected by extended-spectrum, beta-lactamase-producing Escherichia coli. The patient was treated with ertapenem for four weeks, and the lesion disappeared on follow-up imaging studies. Splenic abscess should be included as a differential diagnosis of splenic cystic lesions in immunocompromised patients.

Focal spleen lesions in visceral leishmaniasis, a neglected manifestation of a neglected disease: report of three cases and systematic review of literature

BACKGROUND

The Mediterranean area is endemic for the zoonotic form of visceral leishmaniasis (VL) caused by Leishmania infantum, a species which has been recently associated with unexpected epidemiological and clinical features.

METHOD

We report the result of a systematic review of the literature on VL unusually presenting with spleen focal lesions, including three previously unpublished cases.

RESULTS

A total of 28 cases of VL with multiple spleen focal lesions were retrieved. Twenty-six (93%) were acquired in the Mediterranean area, where L. infantum is endemic. Thirteen cases were diagnosed in children, and the remaining 15 cases in middle-aged adults, of whom 9 were immunosuppressed. Four patients (14%) underwent diagnostic splenectomy, while the diagnosis was confirmed by less invasive techniques in the remaining patients. The most common radiological patterns were: multiple subcentimetric or centimetric spleen lesions (size ≤ 1 cm in 14 of 19 cases, 74%), hypoechoic at ultrasonography (25 of 26 cases, 99%) and hypodense at CT scan (9 of 10 cases, 90%). PET-CT (available for four patients) showed an intense FDG spleen uptake. MRI and contrast-enhanced ultrasonography, available for two and one cases each, showed complex patterns.

CONCLUSIONS

VL must be added to the list of possible differential diagnosis of spleen focal lesions and health care provider awareness about this condition will avoid unnecessary invasive diagnostic procedures.