Lower limb lymphedema staging based on magnetic resonance lymphangiography

OBJECTIVE

Dermal backflow (DBF) and reduced lymphatic visualization are common findings of lymphedema on various imaging modalities. However, there is a lack of knowledge about how these findings vary with the anatomic location and severity of lymphedema, and previous reports using indocyanine green lymphography or lymphoscintigraphy show variable results. Magnetic resonance lymphangiography (MRL) is expected to clarify this clinical question due to its superior ability for lymphatic visualization. This retrospective study aimed to investigate the following: (1) Are there any characteristic patterns for DBF and lymphatics' visualization, depending on the anatomic location within lower limbs and severity of lymphedema? (2) Is it possible to classify the severity of lymphedema based on MRL findings?

METHODS

Two radiologists performed consensus readings of MRL of 56 patients (112 limbs) with lower-limb lymphedema. The frequency of visualized DBF and lymphatics was analyzed in six regions in each lower limb. The results were compared with the International Society of Lymphology clinical stages and etiology of lymphedema. Characteristic findings were categorized and compared with the clinical stage and duration of lymphedema.

RESULTS

DBF and lymphatics were observed more frequently in the distal regions than the proximal regions of lower limbs. DBF appeared more frequently as the clinical stage increased, reaching statistical significance (P < 10^-3) between stages 0 or I and II. DBF above the knee joint was rarely observed (0.48%) in early stages (0 and I) but appeared more frequently (13.5%, P < 10^-5) in stage II. Lymphatics appeared less frequently as the stage progressed, with significant differences (P < .05) between stages I and II and between II and III. The frequency of lymphatics above the knee joint decreased significantly (P < .05) between stages I and II and between II and III as the stage progressed, reaching 0% in stage III. An MRL staging was proposed and showed significant positive correlations with the clinical stage (r = 0.79, P < .01) and the duration of lymphedema (r = 0.57, P < .01).

CONCLUSIONS

MRL-specific patterns of DBF and lymphatics that depended on the site within the lower limb and clinical stage were shown. The DBF pattern differed from those observed in previous studies with other imaging techniques. The proposed MRL staging based on these characteristic findings allows new stratification of patients with lymphedema. Combined with its excellent ability to visualize lymphatic anatomy, MRL could enable a more detailed understanding of individual patient's pathology, useful for determining the most appropriate treatment.

Diffuse Alveolar Hemorrhage Associated with Dilated Cardiomyopathy and Sleep Apnea Syndrome

We herein report a case of diffuse alveolar hemorrhage (DAH) associated with dilated cardiomyopathy (DCM) and sleep apnea syndrome (SAS) in a 47-year-old man. The patient exhibited recurring dyspnea and bloody sputum. Chest radiography showed bilateral diffuse infiltrative opacities without pleural effusion. A bronchoscopic analysis of bronchoalveolar lavage fluid revealed hemosiderin-laden macrophages. Based on these findings, he was diagnosed with DAH. Laboratory and pathological findings ruled out the possibility of collagen diseases and vasculitis. Overnight polysomnography revealed concomitant severe obstructive SAS. Treatment with continuous positive-pressure ventilation and pharmacological therapy for DCM prevented recurrence of DAH.

Combining the Tumor Contact Length and Apparent Diffusion Coefficient Better Predicts Extraprostatic Extension of Prostate Cancer with Capsular Abutment: A 3 Tesla MR Imaging Study

Purpose: To assess the diagnostic performance of the tumor contact length (TCL) and apparent diffusion coefficient (ADC) for predicting extraprostatic extension (EPE) of prostate cancer with capsular abutment (CA).

Methods: Ninety-three patients with biopsy-proven prostate cancer underwent 3-Tesla MRI, including diffusion-weighted imaging (b value = 0, 2000 s/mm²) and radical prostatectomy. Two experienced radiologists, blinded to the clinicopathological data, retrospectively assessed the presence of CA on T2-weighted imaging (T2WI). TCL on T2WI and ADC values were measured on detecting CA in prostate cancer. We used the receiver operating characteristic curves to assess the diagnostic performance of TCL and ADC values for predicting EPE.

Results: CA was present in 58 prostate cancers among 93 patients. The cut-off value for TCL was 6.9 mm, which yielded an area under the curve (AUC) of 0.75. This corresponded to a sensitivity, specificity, and accuracy of 84.2%, 61.5%, and 69.0%, respectively. The cut-off value for ADC was 0.63 × 10^–3 mm²/s, which yielded an AUC of 0.76. This, in turn, corresponded to a sensitivity, specificity, and accuracy of 84.2%, 59.0%, and 67.2%, respectively. The combined cut-off value of TCL and ADC yielded an AUC of 0.82. The specificity (84.6%) and accuracy (81.0%) of the combined value were superior to their individual values (P < 0.05).

Conclusion: A combination of TCL and ADC values provided high specificity and accuracy for detecting EPE of prostatic cancer with CA.

Applicability of ultrasonography for detection of marginal sinus placenta previa

This study aimed to examine whether marginal sinus placenta previa, defined as when the marginal sinus just reaches the internal cervical os and placental parenchyma might be >2 cm from the internal cervical os, can be diagnosed using ultrasonography (US). We identified the placenta previa cases that underwent both US and magnetic resonance imaging (MRI) between April 2010 and December 2018 at our institution. The diagnostic discrepancies for marginal sinus placenta previa between US and MRI were examined retrospectively. Of the 183 cases of placenta previa, 28 (15.3%) cases were diagnosed as marginal sinus placenta previa using MRI. Among them, 18 cases (64.3%) could also be diagnosed using US. The sensitivity and specificity of the diagnosis of marginal sinus placenta previa using US were 64.3% and 92.9%, respectively. A change in US diagnosis occurred in 10 (35.7%) cases, all of which were diagnosed with low-lying placenta previa or marginal placenta previa and did not develop any serious miserable obstetrical outcomes. In conclusion, the diagnostic accuracy of US for detecting marginal sinus placenta previa was not significant. MRI examination may be required to accurately categorize the types of placenta previa.

A rare case of isolated splenic sarcoidosis: A case report and literature review

Sarcoidosis is a multisystemic granulomatous disease. It is rarely isolated in the spleen. The present report describes a case of isolated splenic sarcoidosis that was diagnosed histologically following laparoscopic splenectomy. A 76-year-old woman, who underwent radical nephroureterectomy 7 years earlier for left renal pelvic cancer and mastectomy 6 years earlier for left breast cancer in another facility, was referred to our hospital for assessment of splenic tumors that were identified during a follow-up examination. The computed tomography scans revealed multiple nodules in the spleen, which had increased in size over 2 years. Positron emission tomography revealed accumulation of [18F]-fluorodeoxyglucose in the spleen. Laparoscopic splenectomy was performed and the diagnosis of sarcoidosis was confirmed histologically. A review of previous reports and the present case suggested that diagnosis of splenic sarcoidosis should be considered when the CT scans show multinodular splenic tumors, and sarcoidosis might be associated with malignant tumors.

Mild metatropic dysplasia: emphasis on the magnetic resonance imaging of articular cartilage thickening

Metatropic dysplasia (MD) is a rare skeletal disorder characterized by short stature due to epiphyseal cartilage and growth plate abnormalities. The severity of MD varies from mild to lethal. This disorder is caused by mutations in the transient receptor potential vanilloid 4 (TRPV4) that encodes calcium-permeable, nonselective cation channels.

A 33-year-old female presented at our hospital with a history of worsening knee pain diagnosed at the previous institution as a case of osteoarthritis. Radiographs of the knee showed epiphyseal irregularity without joint space narrowing. On MRI, fat-suppressed proton density-weighted imaging revealed thickened articular cartilage with a smooth surface and an abnormal signal intensity of the subchondral bone; T₁ weighted imaging demonstrated irregularity of the epiphysis. These findings and the familial history (both her children had TRPV4 mutations) led to the suspicion that her condition could be due to mosaicism for TRPV4 mutation. To the best of our knowledge, this is the first report of MRI findings focusing on articular cartilage thickening in a patient with mild MD. Bone dysplasia including MD should be considered in young patients with articular cartilage thickening and subchondral bone irregularities on MRI.

Acquired Cystic Disease-Associated Renal Cell Carcinoma Extending to the Renal Pelvis Mimicking Urothelial Carcinoma on Computed Tomography (CT): Two Case Reports

Case series

Patients: Male, 66-year-old • Male, 67-year-old

Final Diagnosis: Acquired cystic disease-associated renal cell carcinoma

Symptoms: Hematuria

Medication: —

Clinical Procedure: —

Specialty: Oncology • Radiology

COVID-19 in older adults: Retrospective cohort study in a tertiary hospital in Japan

AIM

We aimed to describe the clinical characteristics, treatment and outcomes of patients with COVID-19 pneumonia, in particular older patients, admitted to tertiary and partner hospitals in Saitama, Japan.

METHODS

We retrospectively reviewed the medical records of patients with COVID-19 pneumonia admitted to tertiary and partner hospitals in Saitama, Japan. Twenty-six patients with COVID-19 were categorized into two groups, i.e., older (≥75 years) and younger adults (≤74 years). We evaluated the clinical characteristics, comorbidities, symptoms, laboratory test results, treatments and outcomes of the patients.

RESULTS

The majority of the older patients had comorbidities, such as dementia, cardiovascular disease and bone fractures. Comorbidities were significantly more frequent in older patients than younger patients. No association was found between age and body temperature or the incidence of respiratory failure. White blood cell count was significantly lower in older patients (P = 0.018) and the decrease in lymphocytes was greater in younger patients (P = 0.009). Computed tomography (CT) of all patients showed non-segmental, peripherally dominant ground-glass opacities consistent with COVID-19 pneumonia. In older patients, antiviral drugs, anticoagulants and anti-inflammatory drugs were administered on a compassionate use basis. The difference in mortality between the older and the younger patients was not statistically significant.

CONCLUSIONS

In older patients, typical clinical symptoms and blood test changes were often absent; however, CT always contained typical findings of COVID-19, suggesting that CT may be a useful diagnostic tool. Our report illustrates that appropriate treatment, taking patient background into consideration, may improve their condition regardless of age. Geriatr Gerontol Int 2020; 20: 1044-1049.

Postoperative pneumonia causes the loss of skeletal muscle volume and poor prognosis in patients undergoing esophagectomy for esophageal cancer

PURPOSES

This retrospective study investigated the effect of postoperative pneumonia on the loss of skeletal muscle volume after esophagectomy for esophageal cancer.

METHODS

A total of 123 patients who had undergone esophagectomy for esophageal cancer and had (30 patients) or did not have (93 patients) postoperative pneumonia were included in the analysis. The association of clinicopathological characteristics with loss of skeletal muscle volume and long-term survival were evaluated in patients with or without postoperative pneumonia.

RESULTS

There were no differences in the psoas muscle volume index (PI), lymphocyte count, serum albumin level, or prognostic nutritional index between the two groups both preoperatively and at 6 months after surgery. The decrease in PI at 6 months after surgery was significant in patients with postoperative pneumonia (- 9.9 ± 2.5%) but not in those without pneumonia (- 2.6 ± 1.6%). Patients with postoperative pneumonia had a significantly increased frequency of asymptomatic pneumonia at 6 months after surgery compared with those who did not have postoperative pneumonia (36.7% vs. 19.4%). Overall survival was significantly poorer in patients with postoperative pneumonia than in those without pneumonia (p < 0.05).

CONCLUSIONS

Postoperative pneumonia was associated with the loss of skeletal muscle volume and asymptomatic pneumonia within 6 months of surgery as well as poorer overall survival.

The use of magnetic resonance imaging to predict placenta previa with placenta accreta spectrum

INTRODUCTION

Massive hemorrhage due to placenta previa with placenta accreta spectrum is associated with high maternal mortality and morbidity. Therefore, accurate prediction of placenta previa with placenta accreta spectrum is essential; magnetic resonance imaging (MRI) is a useful tool for this purpose. This study investigated novel predictors of anterior and posterior placenta previa with placenta accreta spectrum using MRI.

MATERIAL AND METHODS

This was a retrospective study at a tertiary obstetrics hospital in Japan. The singleton patients with placenta previa who were scanned with MRI prenatally and had a cesarean section at our institution between 2007 and 2018 were included. The prediction of anterior and posterior placenta previa with placenta accreta spectrum was evaluated using four MRI findings: heterogeneous signals in the placenta, dark T2-weighted intraplacental bands, myometrial thinning or interruption, and focal uterine bulging. The prediction of posterior placenta previa with placenta accreta spectrum was performed using the quantification of cervical varicosities, which were defined as the ratio of the distance between the minimum distance from the most dorsal cervical varicosities (a) to the deciduous and amniotic placenta (b) on a sagittal image.

RESULTS

Among 202 patients, 14 (6.9%) patients were pathologically diagnosed as having placenta accreta spectrum. Further, 38 (18.8%) patients had anterior placenta previa and 164 (81.2%) patients had posterior placenta previa. When anterior placenta previa with placenta accreta spectrum was predicted using at least one of the four MRI findings, the sensitivity and specificity of the anterior placenta previa with placenta accreta spectrum were 87.5% and 86.7%, respectively. In contrast, the sensitivity and specificity of posterior placenta previa with placenta accreta spectrum were 42.9% and 96.2%, respectively. But when the A/B ratio was set at 0.20, the sensitivity and specificity of the prediction for posterior placenta previa with placenta accreta spectrum using cervical varicosities were 100.0% and 89.2%, respectively.

CONCLUSIONS

The findings of MRI to predict the anterior placenta previa with placenta accreta spectrum were different from posterior placenta previa. The cervical varicosities may be useful in predicting posterior placenta previa with placenta accreta spectrum.

Quantitative analysis of the anatomical changes in the scalp and hair follicles in androgenetic alopecia using magnetic resonance imaging

BACKGROUND

Although the structural changes of the scalp in androgenetic alopecia (AGA) have been reported, these changes have been poorly understood. It is expected that modern MRI would visualize the scalp anatomy in vivo. This study aimed to explore whether AGA causes (a) changes in the thickness of the scalp, (b) anatomical changes in the hair follicles, and (c) changes in the signal intensity of MRI.

MATERIALS AND METHODS

Twenty-seven volunteers underwent MRI for hair and scalp (MRH) and were categorized into two according to the Hamilton-Norwood Scale: the "AGA group" and the "normal group." Two radiologists analyzed the thickness and signal intensity of the scalp, and the depth of hair follicles. These measurements were compared between the two groups.

RESULTS

The thickness of the hypodermis and the entire scalp was significantly thinner in the AGA group than in the control group. The AGA group had significantly shallower depth of hair follicles and relative depth of the hair follicles to that of the entire scalp than the normal group. The hypodermis showed higher signal intensity in the AGA group than the normal group.

CONCLUSION

MRH allowed noninvasive visualization of the scalp anatomy and demonstrated the thinner nature of the entire scalp and hypodermis, along with the shallower depth of the hair follicles in the AGA group in comparison to the normal group. Additionally, MRH demonstrated the increased MR signal intensity in the scalp associated with AGA. MRH may be a promising new method for quantitative and objective analyses of AGA.

MR Imaging of Hair and Scalp for the Evaluation of Androgenetic Alopecia

Purpose:

Although androgenetic alopecia (AGA) is a common cause of hair loss, little is known regarding the magnetic resonance imaging (MRI) of the AGA or scalp. This study aimed to analyze whether MRI for hair and scalp (MRH) can evaluate anatomical changes in the scalp caused by AGA.

Methods:

Twenty-seven volunteers were graded for the severity of AGA using the Hamilton–Norwood Scale (HNS), commonly used classification system. All subjects underwent MRH; two radiologists independently analyzed the images. As a quantitative measurement, the number of hair follicles was analyzed and compared with the HNS. As a qualitative analysis, each MRH scan was visually graded in terms of the severity of alopecia, using a 4-point MR severity score. The scores were compared with the HNS.

Results:

The volunteers were divided into two groups of 12 and 15 males without and with AGA at their vertex, respectively. Inter-observer agreements for the hair count and the MR severity score were excellent. The mean hair count on MRI in the normal group was significantly higher than that in the AGA group (P < 10⁻⁴). The MR severity score in the AGA group was significantly more severe than that in the control group (P < 10⁻⁴). In terms of the presence or absence of thinning hair, the MR severity score was consistent with the HNS determined by a plastic surgeon in 96% of cases. MR severity scores of clinically moderate AGA cases were significantly lower than those of severe cases (P = 0.022).

Conclusion:

MRH could depict scalp anatomy showing a clear difference between AGA and normal scalps, in both hair count and subjective visual assessment. The MR severity score was in good agreement with the clinical stages by HNS. The results support the potential of MRH as a promising imaging technique for analyzing healthy and pathological scalps.

Balloon-occluded retrograde glue embolization for intractable lymphorrhea from bilateral iliac lymphatics following surgery for rectal cancer

Lymphorrhea is a rare complication of rectal surgery. Although percutaneous embolization of thoracic or lymphatic ducts is now increasingly being reported for various types of lymphatic leakage, there are only sparse data on lymphatic interventions for lymphorrhea following rectal surgery. A novel balloon-occluded retrograde lymphatic embolization (BRLE) technique can be a simple and effective option for intractable lymphorrhea. We report a case of a man with infected lymphorrhea after rectal resection. Transperineal drainage was performed; however, lymphatic leakage persisted after 1 month of conservative treatment. Lymphangiography revealed multifocal leaks from bilateral iliac lymphatics. The proposed BRLE technique was performed via a balloon catheter inserted through the transperineal drainage. The balloon allowed occlusion of lymphatic outflow and forceful retrograde injection to achieve denser accumulation of n-butyl cyanoacrylate. Tight embolization of bilateral iliac lymphatics and drastic improvement of the leakage was achieved. To the best of our knowledge, this is the first report of percutaneous embolization for lymphorrhea after rectal surgery. This case supports the efficacy of the BRLE as a simple and effective therapeutic option for such persistent multifocal lymphatic leaks.

Histological differences in cancer cells, stroma, and luminal spaces strongly correlate with in vivo MRI-detectability of prostate cancer

The current study aimed to investigate the plausible histopathological factors that affect the detectability of prostate cancers on multiparametric magnetic resonance imaging (MP-MRI). This retrospective study included 59 consecutive patients who had undergone MP-MRI and subsequent radical prostatectomy. The cases were standardized according to the tumor size ranging from 10 to 20 mm on the final pathological diagnosis. Histopathological review and semi-automated imaging analysis were performed to evaluate the relative area fractions of the histological components, including cancer cells, stroma, and luminal spaces. Among the 59 prostatectomy specimens, no case showed two or more foci of cancer that matched the size criteria. Of the 59 lesions, 35 were MRI-detectable [Prostate Imaging Reporting and Data System (PIRADS) score of 3 or greater] and 24 were MRI-undetectable (PIRADS score of 2 or less). No significant differences were observed in Gleason Grade Group, percentage of Gleason pattern 4, and predominant subtype of Gleason pattern 4 between MRI-detectable and MRI-undetectable cancers. On the other hand, significantly higher mean area fraction of cancer cells (60.9% vs. 42.7%, P < 0.0001) and lower mean area fractions of stroma (33.8% vs. 45.1%, P = 0.00089) and luminal spaces (5.2% vs. 12.2%, P < 0.0001) were observed in MRI-detectable cancers than in MRI-undetectable cancers. In a multivariable analysis performed upon exclusion of area fraction of stroma due to its multicollinearity with that of cancer cells, area fractions of cancer cells (P = 0.0031) and luminal space (P = 0.0035) demonstrated strong positive and negative correlation with MRI-detectability, respectively. Changes in cancer cells, stroma, and luminal spaces, rather than conventional histological parameters, could be considered one of the best predictors to clinical, in vivo MRI-detectability of prostate cancer.

Mobile Spinal Schwannoma with a Completely Cystic Appearance

Patient: Female, 48

Final Diagnosis: Spinal schawnnoma

Symptoms: Dysuria • leg pain

Medication: —

Clinical Procedure: —

Specialty: Orthopedics and Traumatology

Magnetic Resonance Imaging Findings of Penile Abscess

A 72-year-old man presented with pain and swelling in the penis, indicating penile infection or abscess. An ultrasound was performed but unable to lead to a diagnosis of abscess. Magnetic resonance imaging with diffusion-weighted imaging was strongly suggestive of penile abscess. The puncture of the abscess was unsuccessful. However, pus was drained spontaneously via the urethra, and the symptoms disappeared eventually. Although ultrasound can be useful, sometimes it might be difficult to distinguish between inflammatory tissue and abscess containing necrotic tissue. Magnetic resonance imaging, especially diffusion-weighted imaging, can be a powerful tool for diagnosing abscess in the penis.

Analysis of Diffusion-weighted MR Images Based on a Gamma Distribution Model to Differentiate Prostate Cancers with Different Gleason Score

Purpose:

Prostate cancer management includes identification of clinically significant cancers that may require curative treatment. Statistical models based on gamma distribution can describe diffusion signal decay curves of prostate cancer. The purpose of this study was to evaluate the ability of parameters obtained with the gamma model in differentiating prostate cancers with different Gleason score values.

Methods:

This study included 155 patients with prostate cancer who underwent multiparametric magnetic resonance imaging prior to prostate biopsy (127 patients) or radical prostatectomy (28 patients) between January 2015 and June 2017; 159 foci of prostate cancer were included in our study. We compared cases scored as Gleason score (GS) 3 + 3 and GS ≥ 3 + 4, and analyzed cases scored as GS ≤ 3+ 4 and GS ≥ 4 + 3 based on the gamma model (Frac < 1.0, Frac < 0.8, Frac < 0.5, Frac < 0.3, and Frac > 3.0), and apparent diffusion coefficient (ADC).

Results:

Among 159 cancerous lesions in 155 patients, 13 (8.2%) were GS 3 + 3 prostate cancers, 51 (32.0%) were GS 3 + 4 prostate cancers, 30 (18.2%) were GS 4 + 3 cancers, and 65 (40.9%) were GS ≥ 4 + 4 cancers. Frac < 0.3, Frac < 0.5, Frac < 0.8, and Frac < 1.0 were significantly higher and ADC values were significantly lower in GS ≥ 4 + 3 cancers than in GS ≤ 3 + 4 cancers (P < 0.01, P < 0.01, P < 0.01, P = 0.01, and P < 0.01, respectively). With receiver operating characteristic (ROC) analysis, Frac < 0.3 and Frac < 0.5 had significantly greater area under the ROC curve for discriminating GS ≥ 4 + 3 cancers from GS ≤ 3 + 4 cancers than ADC (P = 0.03, P < 0.01, respectively).

Conclusion:

Frac < 0.3 and Frac < 0.5 showed higher diagnostic performance than ADC for differentiating GS ≥ 4 + 3 from GS ≤ 3 + 4 cancers. The gamma model may add additional value in discrimination of tumor grades.

Tomato endo beta-mannanase: A candidate of potential tomato allergen protein detected with human monoclonal antibody established from a patient suffered from Japanese cedar pollinosis

Peripheral blood lymphocytes from a patient allergic to Japanese cedar pollens were transformed by Epstein-Barr virus infection. Some transformed B-lymphoblastoid cells (BLCs) secreted IgM class antibodies to cedar pollen extracts and tomato fruit extracts. One stable human-mouse hybridoma clone Y-22-3-3 secreting IgM class monoclonal antibody to tomato fruit extracts was established by cell fusion of BLCs with mouse myeloma cells. Western blot analysis of tomato extracts showed Y-22-3-3 monoclonal antibody recognized a tomato protein with a molecular weight of 40 kDa. The CBB-stained 40 kDa protein from antibody-affinity chromatography was analyzed by MALDI-TOF/TOF, and identified as tomato endo-beta-mannanase, which was previously reported as one of the potential candidates for tomato allergens.

Bosniak Category III Renal Cysts Caused by Crizotinib in an Anaplastic Lymphoma Kinase Gene-Rearranged Non-Small Cell Lung Cancer Patient

Bosniak category III renal cystic masses are often treated with surgical resection because of high risk of malignancy. Crizotinib is an anaplastic lymphoma kinase (ALK) inhibitor used to treat ALK gene-rearranged non-small cell lung cancer and reported to be associated with complex renal cyst formation. We herein report a case of Bosniak category III renal cysts occurred in a crizotinib-treated ALK gene-rearranged non-small cell lung cancer patients. The cysts regressed spontaneously after cessation of crizotinib and we could thus avoid unnecessary surgical resection.

The added value of tomosynthesis in endoscopic retrograde cholangiography with radiography for the detection of choledocholithiasis

OBJECTIVE

The diagnostic performance of endoscopic retrograde cholangiography (ERC) with radiography is imperfect. We assessed the value of adding tomosynthesis to ERC with radiography for the detection of choledocholithiasis.

METHODS

This study included 102 consecutive patients (choledocholithiasis/non-choledocholithiasis, n = 57/45), who underwent both radiography and tomosynthesis for ERC in the same examination and were not diagnosed with malignancy. The reference standard for the existence of choledocholithiasis was confirmed by endoscopic stone extraction during ERC, intraoperative cholangiography, or follow up with magnetic resonance cholangiopancreatography (n = 78, 11, and 13, respectively). A gastroenterologist and a radiologist independently evaluated the radiographs and the combination of tomosynthesis and radiographic images in a blinded and randomised manner. Receiver operating characteristic analysis was used for statistical analysis.

RESULTS

The areas under the receiver operating characteristic curve for combined tomosynthesis and radiography were significantly higher than those for radiography alone for both readers: Reader 1/Reader 2, 0.929/0.956 [95% confidence interval (CI), 0.861-0.965/0.890-0.983) vs 0.803/0.769 (95% confidence interval, 0.707-0.873/0.668-0.846), respectively (p = 0.0047/< 0.0001).

CONCLUSION

Adding tomosynthesis to radiography improved the diagnostic performance of ERC for detection of choledocholithiasis. Advances in knowledge: Adding tomosynthesis to radiography improves detection of choledocholithiasis and tomosynthesis images can be obtained easily after radiographs and repeated immediately.