Israel Medical Association Journal

Background: Right hydronephrosis secondary to acute appendicitis is an under-reported phenomenon with only several case reports published.

Objectives: To assess the incidence of this phenomenon in our database of patients diagnosed with acute appendicitis.

Methods: Data were collected on 1092 patients who underwent surgery due to acute appendicitis between 2003 and 2007 in our tertiary medical center. The data entailed demographic, surgical, and hospitalization parameters including ultrasound or computed tomography examinations and presence of right hydronephrosis prior to surgery.

Results: Out of 1092 patients, appendicitis was eventually diagnosed in 87.4% of the patients. Only 594 (54%) had preoperative imaging performed prior to surgery (ultrasound or computed tomography). Out of these 594 patients, 21 (3.5%) had a new right hydronephrosis diagnosed and all had appendicitis with 15/21 (71%) having a retrocecal appendix. Of those with retrocecal appendix, 10 were pregnant women (48%). Erythrocyturia was present in 15/21 patients (71%) and in 10/11 of patients (91%) after excluding those who were pregnant. No significant differences were seen in patients with hydronephrosis regarding age, hospitalization, and surgery time. In all patients, an ultrasound was performed 2 weeks after surgery demonstrating the disappearance of hydronephrosis. Median follow-up time was 41.7 months (range 14.8–118.4 months).

Conclusions: Our study shows that 3.5% of our cohort had right hydronephrosis secondary to acute appendicitis. Although this presentation is very rare, physicians should be aware of this phenomenon and the risk for delayed diagnosis and treatment of acute appendicitis.

Background: Enthesopathy may lead to calcification of the stylohyoid ligament and can cause elongation of the styloid process (SP).

Objectives: To evaluate whether SP elongation is associated with two common enthesitis-related diseases: ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH).

Methods: Cervical spine computed tomography (CT) examinations of patients with DISH (n=64, Resnick criteria), AS (n=24, New York criteria) and a controls (no radiological signs of DISH or AS, n=54) were retrospectively evaluated. The DISH group was further divided into patients with and without cervical DISH. The length of right and left SP was measured independently by two readers on coronal and sagittal curved reformats. The average right and left styloid length and average length per person were compared among the groups.

Results: Demographic characteristics were similar between the DISH and control groups (average age 68.2 ± 15.7, 69.2 ± 12.7 years, male:female ratio 48:16 and 35:19, respectively, P > 0.05), whereas age was significantly lower (average age: 53 ± 15 years, P < 0.0001) in the AS group, which was also composed mainly of men. The AS and DISH groups had significantly longer SP compared to controls (AS 37.9 ± 9.6 mm, DISH 34.4 ± 9 mm, control 30.3 ± 10.1 mm, P < 0.05). There was no correlation between age and SP length. Inter-reader reliability of SP measurements was excellent in all groups (ICC = 0.998, P < 0.0001).

Conclusions: SP elongation is associated with both AS and DISH substantiating the enthesopathy-related pathophysiology of this finding.

Background: Facial rejuvenation using different dermal and sub-dermal injectable compounds is a popular cosmetic procedure which may pose a diagnostic dilemma to the radiologist.

Objectives: To describe the appearance of cosmetic facial fillers on PET-CT.

Methods: All PET-CT exams performed between January 2015 and May 2017 in which findings suggestive of prior facial filler procedures was evident and where anamnestic confirmation with the patient was possible were reviewed.

Results: We describe five females who had undergone facial filler procedures leading to calcifications around the mouth and nasolabial triangle.

Conclusions: Familiarity with the appearance of such cosmetic procedures on PET-CT is of paramount importance in order to avoid misinterpretation of the findings leading to unnecessary apprehension and work-up.

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: While patients presenting to emergency departments (ER) with chest pain are increasingly managed in chest pain units (CPU) that utilize accelerated diagnostic protocols for risk stratification, such as single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), data are lacking regarding the prognostic implications of mildly abnormal scans in this population.

Objectives: To evaluate the prognostic implications of mildly abnormal SPECT MPI results in patients with acute chest pain.

Methods: Of the 3753 chest pain patients admitted to the CPU at the Leviev Heart Center, Sheba Medical Center 1593 were further evaluated by SPECT MPI. Scans were scored by extent and severity of stress-induced perfusion defects, with 1221 patients classified as normal, 82 with myocardial infarction without ischemia, 236 with mild ischemia, and 54 with more than mild ischemia. Mild ischemia patients were further classified to those who did and did not undergo coronary angiography within 7 days.

Results: Mild ischemia patients who underwent coronary angiography were more likely to be male (92% vs. 81%, P = 0.01) and to have left anterior descending ischemia (67% vs. 42%, P = 0.004). After 50 months, these patients returned less often to the ER with chest pain (53% vs. 87%, P < 0.001) and had a lower combined endpoint of acute coronary syndrome and death (8% vs. 16%, P < 0.001).

Conclusions: Compared to patients with chronic stable angina, patients presenting with acute chest pain exhibiting mildly abnormal SPECT MPI findings should perhaps undergo a more aggressive diagnostic and therapeutic approach.

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: Four-dimensional parathyroid computed tomography (4DCT) is a relatively new parathyroid imaging technique that provides functional and highly detailed anatomic information about parathyroid tumors.

Objective: To assess the accuracy of 4DCT for the preoperative localization of parathyroid adenomas (PTAs) in patients with biochemically confirmed primary hyperparathyroidism (PHPT) and a history of failed surgery or unsuccessful localization using ^99mTc-sestamibi scanning and ultrasonography.

Methods: Between January 2013 and January 2015, 55 patients with PHPT underwent 4DCT at Hillel Yaffe Medical Center, Hadera, Israel. An initial unenhanced scan was followed by an IV contrast injection of nonionic contrast material (120 ml of at 4 ml/s). Scanning was repeated 25, 60, and 90 seconds after the initiation of IV contrast administration. An experienced radiologist blinded to the earlier imaging results reviewed the 4DCT for the presence and location (quadrant) of the suspected PTAs. At the time of the study, 28 patients had undergone surgical exploration following 4DCT and we compared their scans with the surgical findings.

Results: 4DCT accurately localized 96% (27/28) of abnormal glands, all of which were hypervascular and showed characteristic rapid enhancement on 4DCT that could be distinguished from Level II lymph nodes. Surgery found hypovascular cystic PTA in one patient who produced a negative 4DCT scan. All patients had solitary PTAs. The scan at 90 seconds provided no additional information and was abandoned during the study.

Conclusions: 4DCT accurately localized hypervascular parathyroid lesions and distinguished them from other tissues. A three-phase scanning protocol may suffice.

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.

 

Background: Trans-catheter valve implantation (TAVI) is a non-surgical alternative for patients with severe aortic stenosis (AS). Pre-procedural computed tomography angiography (CTA) allows accurate “road mapping,” aortic annulus sizing and the detection of incidental findings.

Objectives: To document the prevalence of non-valvular extra-cardiac findings on CTA prior to TAVI and the impact of these findings on the procedure.  

Methods: Ninety AS patients underwent CTA as part of pre-TAVI planning. Scans extended from the clavicles to the groin. Non-vascular non-valvular findings were documented and graded as follows: (A) significant findings causing TAVI cancellation or postponement, (B) significant findings leading to a change in the TAVI procedure approach, (C) non-significant findings not affecting the TAVI procedure. 

Results: TAVI was planned for 90 patients; their average age was 80.2 ± 7.5 years, 53% were females. Overall, non-valvular cardiac, extra-cardiac and extra-vascular significant and non-significant incidental findings were documented in 97% of scans (87/90). Significant pathologies causing TAVI cancellation or postponement (category A) were documented in 8%. Significant findings affecting the TAVI procedure (category B) were found in 16% of patients. 

Conclusions: Pre-TAVI CTA detected non-valvular extra-vascular pathologies leading to procedure cancellation/postponement or procedure modification in 8% and 16%, respectively. Comprehensive CTA evaluation that acknowledges the importance of such findings is of major importance since it might alter the TAVI procedure or even render it inappropriate. 

 

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.