Adhesive Small-Bowel Obstruction: Value of CT in Identifying Findings Associated with the Effectiveness of Nonsurgical Treatment

This retrospective study of imaging findings in patients with SBO due to adhesions is mostly valuable because the author's have tried to actually correlate the findings to actual impact on management. It is a moderate sized review of 221 patients with SBO on CT, and review of findings on those studies. The specific features they identify as predictive of successful non-operative management is the presence of fewer than two beak signs and the presence of an anterior parietal adhesion are predictive of successful non-operative management. U shaped or C shaped loops were predictive of non-operative management failure.

PICO Analysis:
Population: patients with SBO on CT
Intervention: non-operative management
Comparison: none
Outcome: successful non-operative management

Reference: Pubmed Full Text

Accuracy of Multiparametric MRI for Prostate Cancer Detection: A Meta-Analysis

This meta-analysis of the current literature found 7 studies meeting their inclusion criteria for assessment of multiparametric MRI for prostate cancer (defined as using both T2-weighted imaging and functional MR techniques DWI and DCEMRI). All studies had to include comparison with either biopsy or surgical histopathology. Studies were assessed for quality using QUADAS-2.

Overall the meta-analysis of pooled data demonstrated a specificity of 0.88 and sensitivity of 0.74 for prostate cancer detection, with variable NPV ranging from 0.65 to 0.94.

The meta-analysis is methodologically sound, but does have a limited pool of only 7 studies to assess. This provides a good overview of the current literature and provides further evidence of the role of MRI in assessment of patients with suspected or diagnosed prostate cancer.

PICO Analysis:
Population: Patients with suspected prostate cancer.
Intervention: Multiparametric prostate MRI.
Comparison: Surgical or Biopsy histopathology.
Outcome: Sensitivity & Specificity.

Reference: Pubmed Full Text

Management of Nodules with Initially Nondiagnostic Results of Thyroid Fine-Needle Aspiration: Can We Avoid Repeat Biopsy?

This retrospective review of followup results from patients with non-diagnostic ultrasound guided thyroid biopsy. Of the 393 nodules with non-diagnostic initial result, only 9 were subsequently diagnosed with malignancy with either repeat FNA or surgical excision, and a very low percentage (2/336) had a malignancy diagnosed on repeat sampling. As such the authors propose ultrasound followup in lieu of repeat biopsy.

They further identify higher risk features including size, male gender and increased age.

While the study is limited as it is a retrospective sampling, it does provide some evidence to guide management of a frequent clinical conundrum in the setting of a non-diagnostic FNA.

PICO Analysis:
Population: Patients with initial negative US guided FNA
Intervention: Repeat FNA
Comparison: Followup US
Outcome: Prevalence of missed malignancy

 Reference: Pubmed Full Text

Repeatability of Diagnostic Features and Scoring Systems for Hepatocellular Carcinoma by Using MR Imaging

This article evaluated the inter-rater reliability of assessing characteristics of liver lesions and overall staging of hepatocellular carcinomas using various staging systems (OTPN, AASLD, and LI-RADS).

10 blinded readers reviewed 100 liver MRI cases assessing lesions for HCC criteria (arterial hyper-enhancement, washout, and pseudocapsule). Readers were also asked to assign an OTPN, AASLD and LI-RADS score (ver. 2013.1) based on their findings.

5 abdominal imaging staff at an OPTN approved liver transplant center (6-11 years of experience) and 5 “novice” radiology residents were selected to be a part of the study. 10 cases were used for training but not included as part of the study results.

High Kappa scores were achieved for the finding of arterial hyper-enhancement (0.67). Moderate scores for wash-out and the presence of a pseudocapsule (0.48 and 0.52 respectively).

As for staging moderate agreement was noted for OPTN staging (0.53) and fair agreement for LI-RADS and AASLD (0.35 and 0.39).

Overall agreement amongst experts was significantly higher in comparison to that of novice residents (P<.001). Interestingly (yet not surprising) agreement between experts for LI-RADS and AASLD was fair to moderate (0.43 and 0.46) in comparison to OPTN (0.64).


PICO Analysis:

Population: Radiologists
Intervention: The effect of experience for interpretation and accurate staging of hepatocellular carcinomas.
Comparison: “experts” versus “novice” residents
Outcome: There is higher consistency and accuracy amongst experts reading liver MRI. There is moderate agreement amongst “experts” for relatively complex classification systems (LI-RADS and AASLD) in comparison to high agreement for OPTN




Advancement in Knowledge:

1. Experience plays a role in the interpretation of Liver MRI
2. There is only moderate agreement amongst “experts” in staging hepatocellular carcinoma using LI-RADS and AASLD.



Reference:
Pubmed Full Text

Advanced-stage Hodgkin Lymphoma: US/Chest Radiography for Detection of Relapse in Patients in First Complete Remission—A Randomized Trial of Routine Surveillance Imaging Procedures

This intriguing study looks at alternatives to PET/CT and CT for followup of Hodgkin lymphoma. The study prospectively enrolled 300 patients into either F18 PET/CT or US + CXR at specified intervals. The US/CXR arm had higher specificity than PET/CT (96% vs 86%), and both arms had similar sensitivity (97.5% vs 100%).
This is an intriguing approach to reduce radiation dose (14.5 mSv per PET/CT vs 0.1 mSv per CXR) in this population who have a high baseline risk of second malignancy (as documented in this study, ~5% 5yr risk of secondary malignancy with no difference between the two arms). Further benefit is the reduced cost of the US/CXR approach, which in Italy was estimated at €1071 per PET/CT vs €103 per US/CXR. There were also lower secondary costs and fewer invasive procedures (eg mediastinoscopy) in the US/CXR arm.
The main limitation is the technical feasibility of performing US screening, in the study this was all done by one 'expert' radiologist, and its extension to other practices may be challenging but is worth considering.

PICO Analysis:
Population: advanced stage Hodgkin Lymphoma
Intervention: US + CXR f/u post initial tx
Comparison: PET/CT f/u post initial tx
Outcome: Sensitivity & specificity for relapse, time to recurrence and cost

Reference: Pubmed Full Text

Diagnostic accuracy and patient acceptance of MRI in children with suspected appendicitis

This prospective study compares 3 strategies for imaging suspected appendicitis. Ultrasound alone, US+conditional MRI and MRI alone. The sensitivity of MRI alone and US + conditional MRI was 100%, ultrasound alone was found to be significantly lower at 76%.
The specificity was found to be comparable among the three investigated strategies; MRI alone 89%, US + conditional MRI 80% and US alone 89%.

The study on a technical basis is quite good, with patients enrolled consecutively and prospectively. Surgical diagnosis or 3mo followup including contact of all patients primary physician was used for clinical followup. While no flowchart is provided in the text documenting the different arms it appears none were lost to followup and all 'positive' cases did proceed to surgery. The study population had a relatively high prevalence of appendicitis at 56%.

Limitations are that the US was performed by radiology residents, and the surgical management is not clear for all cases which makes assessment of the applicability of these results to different practices (such as in Canada or US) somewhat challenging, and may explain the relatively low sensitivity of US alone despite relatively high subjective quality evaluation of the US studies.

PICO Analysis:
Population: pediatric patients 4-18yo (mean 12yo)
Intervention: US alone, MRI alone or US + conditional MRI
Comparison: Surgical dx or 3mo clinical followup
Outcome: Sensitivity and Specificity

Reference: Pubmed Full Text

Comparison of Two-dimensional Synthesized Mammograms versus Original Digital Mammograms Alone and in Combination with Tomosynthesis Images

This study is a case control series of patients assessing the performance of digital breast tomosynthesis + simulated mammogram with tomosynthesis + FFDM. The series of 123 patients included both normals (defined as 1yr followup normal mammo) as well as biopsy/surgery proven benign and malignant lesions. Lesions included both asymmetries and microcalcifications.

Overall the study demonstrates similar performance of the simulated mammogram and FFDM when both are combined with tomosynthesis. The study did not report the dose of the two techniques in the study used. This study is further limited in that it is a population of convenience as opposed to a true screening population, and future work with true prospective screening is required for this technology. Another limitation of this study (and most assessments of the simulated 2D mammogram) is the lack of comparison between FFDM alone and Tomo+simulated mammo in a non-inferiority analysis for sensitivity and assessment of specificity, and a true comparison of the total dose from the two techniques.

PICO Analysis:
Population: Case-Control series of 123 patients
Intervention: Tomosynthesis + Simulated 2D Mammogram
Comparison: Tomosynthesis + FFDM
Outcome: ROC

Reference: Pubmed Full Text