Israel Medical Association Journal

Background: Computed tomography (CT) brain perfusion is a relatively new imaging method that can be used to differentiate patients following epileptic seizures in the setting of acute neurological deficits (e.g., hemiparesis, hemiplegia, hemianopsia, aphasia) who arrive at the emergency room with a suspected stroke.

Objectives: To evaluate brain perfusion changes in patients who had an epileptic seizure.

Methods: We retrospectively identified 721 patients who presented at our stroke center between 2012 and 2015 with a suspected acute stroke and underwent examination thorough a stroke protocol, including cerebral CT perfusion (CTP) and CT angiography (CTA) within 8 hours from the onset of symptoms. 

Results: Out of 721 patients, 25 presented with ictal electroencephalography (EEG) findings within 24–72 hours from symptom onset without evidence of vascular occlusion on CTA. While 15 patients had to be excluded from the study due to concomitant brain pathology, we found a specific reduction in cerebral blood volume and cerebral blood flow occurring at the ictal zone, which was identified by a post hoc EEG investigation. 

Conclusions: Our study shows that CTP is an easily accessible tool in emergency department setting for the detection of changes in blood flow dynamics among postictal patients. Thus, we propose the use of CTP in emergency settings to discriminate between postictal changes and acute vascular events. 

 

Background: Pulmonary infiltrates (PIs) detected in patients with non-Hodgkin lymphoma (NHL) may present a diagnostic challenge due to their wide differential diagnosis, including infection, pulmonary lymphoma and immunochemotherapy-associated pulmonary toxicity.

Objectives: To characterize therapy-associated PIs by positron emission tomography/computed tomography (PET/CT) imaging.

Methods: We conducted a historical analysis of fluorodeoxyglucose-PET/CT (¹⁸F-FDG-PET/CT) PIs in NHL patients treated with combined immunochemotherapy including rituximab. Incidence of PIs, radiological features, patients’ characteristics, underlying NHL type, rituximab/chemotherapy dosing schedules, and symptoms were recorded. Therapy-associated PIs were defined as new or worsening PIs appearing after treatment onset, without evidence of active pulmonary lymphoma or infection.

Results: Among 80 patients who met the pre-specified criteria, therapy-associated PIs were identified in 17 (21%), 6 of whom had accompanying symptoms. Increased FDG uptake was observed in nine, and PI resolution in six. The incidence of PIs was higher in females and in patients with aggressive lymphoma, at advanced stages, and in those who had received treatment consisting of a combination of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisolone every 14 days (R-CHOP-14).

Conclusions: This characterization of therapy-associated PIs may support the clinician managing NHL patients. Further prospective studies are needed to establish the role of each therapeutic component and the natural history of this phenomenon.

Background: Accurate assessment of liver fibrosis is crucial for the management of patients with hepatitis C virus (HCV) infection.

Objectives: To evaluate the performance of liver segment-to-spleen volume ratio in predicting the severity of liver fibrosis.

Methods: Sixty-four consecutive HCV patients were enrolled in this retrospective study. All patients underwent contrast-enhanced computed tomography (CT) and were divided into three groups based on their hepatic fibrosis stage evaluated by shear-wave elastography (SWE): non-advanced (F0–F1, n=29), advanced (F2, n=19) and severe fibrosis (F3–F4, n=16). Using semi-automated liver segmentation software, we calculated the following liver segments and spleen volumes for each participant: total liver volume (TLV), caudate lobe (CV), left lateral segment (LLV), left medial segment (LMV), right lobe (RV) and spleen (SV), a well as their ratios: CV/SV, RV/SV, LLV/SV, LMV/SV and TLV/SV.

Results: RV/SV was found to discriminate between patients with non-advanced and advanced fibrosis (P = 0.001), whereas SV, CV, RV, TLV/SV, LMV/SV and RV/SV discriminated between patients with advanced and severe fibrosis (P < 0.05). RV/SV ≤ 3.6 and RV ≤ 2.9 were identified as the best cutoff values to differentiate non-advanced from advanced fibrosis and advanced from severe fibrosis with sensitivities of 72.2% and 92.7%, specificities of 72.7% and 77.8%, and with an area under the receiver operating characteristic (ROC) curve of 0.797 and 0.847, respectively (P ≤ 0.002).

Conclusions: RV/SV may be used for the assessment and monitoring of liver fibrosis in HCV patients prior to the administration of antiviral therapy, considering SWE as the reference method.

Background: Despite the lack of clinical studies supporting the use of routine surveillance FDG-positron emission tomography (PET) in patients with diffuse large B cell lymphoma (DLBCL) who achieved remission, many centers still use this strategy, especially in high risk patients. Surveillance FDG-PET computed tomography (CT) is associated with a high false positive (FP) rate in DLBCL patients. 

Objectives: To investigate whether use of specific CT measurements could improve the positive predictive value (PPV) of surveillance FDG-PET/CT. 

Methods: This retrospective study included DLBCL patients treated with CHOP or R-CHOP who achieved complete remission and had at least one positive surveillance PET. CT-derived features of PET-positive sites, including long and short diameters and presence of calcification and fatty hilum within lymph nodes, were assessed. Relapse was confirmed by biopsy or consecutive imaging. The FP rate and PPV of surveillance PET evaluated with/without CT-derived measurements were compared. 

Results: Seventy surveillance FDG-PET/CT scans performed in 53 patients were interpreted as positive for relapse. Of these studies 25 (36%) were defined as true-positive (TP) and 45 (64%) as FP. Multivariate analysis found long or short axis measuring ≥ 1.5 and ≥ 1.0 cm, respectively, in PET-positive sites, International Prognostic Index (IPI) ≥ 2, lack of prior rituximab therapy and FDG uptake in a previously involved site, to be independent predictors of true positive surveillance PET (odds ratio 5.4, 6.89, 6.6, 4.9, P < 0.05 for all). 

Conclusion: PPV of surveillance PET/CT may be improved by its use in selected high risk DLBCL patients and combined assessment of PET and CT findings.

 

Abstract

Background: Only a few studies have compared the accuracy of magnetic resonance enterography (MRE) and computed tomography enterography (CTE) in the diagnosis of Crohn's disease and its complications.

Objectives: To compare the sensitivity of MRE and CTE analysis in their ability to detect, sign-by-sign, 10 classical imaging signs of Crohn's disease.

Methods: The study group comprised 42 biopsy-proven Crohn's disease patients who underwent both CTE and MRE within an average period of 6 weeks. Agreement between the two modalities in detecting the 10 most significant radiological signs of CD was evaluated using the Kappa index. The sensitivity of MRE and CTE was calculated using a standard of reference composed of all the findings seen by CTE and/or MRE. We analyzed MRE and CTE sensitivity separately in two groups, according to the time interval between the examinations.

Results: Agreement between CTE and MRE was more than 70% in 8 of the 10 signs: mural thickening, phlegmon, stenosis, skip lesions, mucosal stratification, fistula, abscess, and creeping fat. The Kappa level of agreement values for CTE versus MRE varied between substantial for phlegmon and skip lesions; moderate for fistula, creeping fat, abscess and mural thickening; and fair for stenosis and dilatation. CTE detected more findings than MRE, except for creeping fat and fistula. There was no significant difference in the sensitivity of CTE and MRE in the two groups defined by the time interval (time < 1.5 and time > 1.5 months) except for detection of dilatation.

Conclusions: Almost all imaging signs of Crohn's disease were detected equally well by both modalities regardless of the time interval between examinations. We therefore consider MRE to be reliable for imaging and follow-up in patients with Crohn's disease who may need recurrent imaging.

Objectives: To evaluate common misinterpretations of head CT scans by radiology residents in a level I trauma center ED.

Methods: We studied 960 head CT scans of patients admitted to our ED from January 2010 to May 2011. They were reviewed separately by two senior neuroradiologists and graded as being unimportant (score of 1), important but not requiring emergent treatment (score of 2), and important requiring urgent treatment (score of 3). We recorded the time of day the examination was performed, the year of residency, the site, subsite and side of the lesion, the pathology, the anatomical mistake, false-positive findings, and the attending neuroradiologists' score.

Results: A total of 955 examinations were interpreted of which 398 had misinterpreted findings that were entered into the database, with the possibility of multiple errors per examination. The overall misinterpretation rate was 41%. The most commonly missed pathologies were chronic infarcts, hypodense lesions, and mucosal thickening in the paranasal sinuses. The most common sites for misdiagnosis were brain lobes, sinuses and deep brain structures. The highest percentage of misinterpretation occurred between 14:30 and 20:00, and the lowest between 00:00 and 08:00 (P < 0.05). The overall percentage of errors involving pathologies with a score of 3 by at least one of the neuroradiologists was 4.7%. Third-year residents had an overall higher error rate and first-year residents had significantly more false-positive misinterpretations compared to the other residents.

Conclusions: The percentage of errors made by our residents in cases that required urgent treatment was comparable to the published data. We believe that the intense workload of radiology residents contributes to their misinterpretation of head CT findings.

Background: Lung disease in patients with famHiat dys-autonomia is caused mainly by recurrent aspiration of gastric contents, food and liquids swallowed incorrectly.

Objective: To describe chest computed tomography findings in patients with familial dyautonomia.

Methods: A retrospective analysis of chest CT findings was performed for 34 FD patients (15 females, 19 males) with a mean age of 18± 12.8 years.

Results: The CT revealed bronchial wall thickening (in 94% of the patients), atelectasis (in 73%), ground glass opacities (in 53%), focal hyperinflation (in 44%), fibrosis (in 29%) and bronchiectasis (in 26%). The extrapulmonary abnormalities were scoliosis (79%) and esophageal dilatation (35%). Silent fractures were noted in two vertebral bodies and one rib.

Conclusions: Pulmonary changes were consistent with chronic inflammation in the bronchi and interstitial tissues. Ground  glass opacities and fibrosis support the theory that these changes could be due to gastric aspiration. Bronchiectasis is less frequent. Esophageal dilatation with fluid overflow adds to aspiration. Fractures can be asymptomaflc and are often missed.