Israel Medical Association Journal

Background: Whole-body integrated positron emission tomography / contrast-enhanced computed tomography (PET/CT) scan is increasingly used in cutaneous lymphomas. However, the value of PET/CT in the detection of cutaneous lesions in primary cutaneous B-cell lymphoma (PCBCL) has barely been investigated.

Objectives: To investigate the diagnostic accuracy of PET/CT in tracking cutaneous involvement in PCBCL.

Methods: A retrospective study was conducted on 35 consecutive patients diagnosed with cutaneous B-cell lymphoma according to the World Health Organization classification who were evaluated with PET/CT as the initial staging procedure before treatment.

Results: Thirty-five patients met the study criteria. In two patients extracutaneous disease was detected by PET/CT and CT and confirmed by biopsy. Of the 33 patients with PCBCL, 26 (79%) had small cell PCBCL (18 marginal-zone, 8 follicle-center lymphoma) and 7 (21%) had large cell PCBCL (3 follicle-center, 3 leg-type, 1 indeterminate). PET/CT detected skin lesions in 3 of 26 patients (12%) with small-cell PCBCL as compared to 6 of 7 patients with large-cell PCBLC (86%), a 7.4-fold detection risk (95% confidence interval, 2.4–22, P = 0.004). The PET-positive subgroup was characterized by larger lesion size (P < 0.001) and a higher Ki-67 proliferation index (P < 0.001).

Conclusions: The sensitivity of PET/CT for detecting cutaneous involvement of lymphomas is low for small-cell PCBCL but high for large-cell types, and thus may facilitate therapeutic strategies.

Background: Implant-related spinal infections are a surgical complication associated with high morbidity. Due to infection, hardware removal may be necessary, which could lead to pseudarthrosis and the loss of stability and alignment.

Objectives: To evaluate the accuracy and diagnostic value of ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) in the workup of patients with suspected implant-related infections of the spine and to assess the clinical impact of PET/CT results on the management of these infections.

Methods: The study included nine consecutive patients with a history of spinal surgery who underwent PET/CT for evaluation of suspected spinal implant related infection. All imaging studies were performed between January 2011 and December 2013. All ¹⁸F-FDG PET/CT scans were performed on an 8 slice PET/CT following an ¹⁸F-FDG injection. Images were scored both visually and semi-quantitatively by a radiology expert. Results were compared to additional imaging studies when available, which were correlated to clinical and bacteriological findings allowing calculation of sensitivity, specificity and accuracy.

Results: Among the patients, five experienced hardware-related spinal infection. ¹⁸F-FDG PET/CT sensitivity was 80%, specificity 100%, and accuracy 88.9%. One scan produced a false negative; however, a second PET/CT scan revealed an infection.

Conclusions: PET/CT was found to be valuable for the diagnosis of postoperative hardware-related spinal infection, especially when other imaging modalities were uninformative or inconclusive. As such, PET/CT could be useful for management of infection treatment.

Background: Acute non-traumatic abdominal pain is typically evaluated by abdomino-pelvic computed tomography (CT) with oral and venous contrast. The accuracy of unenhanced CT for diagnosis in this setting has not been widely studied.

Objectives: To assess the accuracy of unenhanced CT in establishing the etiology of acute non-traumatic abdominal pain.

Methods: We retrospectively reviewed the medical and imaging records of patients aged ≥ 18 years who presented to the emergency department (ED) during a 6-month period with acute non-traumatic abdominal pain of unknown etiology, and who were evaluated with non-contrast CT within 24 hours of ED admission. Clinical details were recorded. A presumptive clinical diagnosis and CT diagnosis were compared to the discharge diagnosis which was considered the reference standard. The requirement for informed consent was waived.

Results: Altogether, 315 patients met the inclusion criteria – 138 males (44%) and 177 females (56%); their mean age was 45 years (range 18–90). Clinical diagnosis correlated with the CT findings in 162 of the cases (51%). CT was accurate in 296/315 cases (94%). The leading diagnosis in cases of a mismatch between CT diagnosis and discharge diagnosis was infection mostly in the urinary tract (12/18). Sensitivity, specificity, positive predictive value and negative predictive value were 91%, 99%, 91% and 85% respectively. The discharge diagnosis was unchanged in the patients who returned to the ED within 1 week of the first admission.

Conclusions: In this study, unenhanced CT proved to be a feasible, convenient and legitimate examination for the evaluation of patients with acute non-traumatic abdominal pain presenting to the ED.

Background: Ga-prostate-specific membrane antigen positron emission tomography/computerized tomography (Ga-PSMA PET/CT) is part of the initial workup of patients with intermediate and high-risk prostate cancer provided by the Israeli national health services.

Objectives: To assess the incidence of metastatic spread in consecutive patients with newly diagnosed cancer, and the potential added value of Ga-PSMA PET/CT to the staging imaging algorithm.

Methods: Patients with newly diagnosed intermediate- and high-risk prostate cancer were referred for initial staging by Ga-PSMA PET/CT between May 2016 and April 2017. Blood prostate-specific antigen (PSA) levels, clinical history, imaging reports and histopathological reports (including Gleason scores) were obtained. Maximal standardized uptake values (SUVmax) were determined for the primary lesions detected within the prostate.

Results: The study included 137 consecutive patients with intermediate- and high-risk disease who underwent Ga-PSMA PET/CT staging. Of these, 75 had Ga-PSMA uptake in both prostate lobes, 57 had unilateral uptake, and 5 patients had no uptake. SUVmax in the primary tumor correlated significantly with PSA levels. Thirty-five patients had increased uptake compatible with metastatic disease involving lymph nodes, bone, and viscera. Twenty-seven patients had available bone scintigraphy results: 18 (69%) of their 26 bone metastases detected by Ga-PSMA PET/CT were missed on bone scintigraphy.

Conclusions: Ga-PSMA PET/CT shows promise as a sole whole-body imaging modality for assessing the presence of soft tissue and bone metastases in the setting of prostate cancer.

Because fragility fractures have an enormous impact on the practice of medicine and global health systems, effective screening is imperative. Currently, dual-energy X-ray absorptiometry (DXA), which has limited ability to predict fractures, is being used. We evaluated the current literature for a method that may constitute a better screening method to predict fragility fractures. A systematic review of the literature was conducted on computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound to evaluate screening methods to predict fragility fractures. We found that ultrasound had sufficient data on fracture prediction to perform meta-analysis; therefore, we analyzed prospective ultrasound cohort studies. Six study populations, consisting of 29,299 individuals (87,296 person-years of observation) and including 992 fractures, were analyzed. MRI was found to be sensitive and specific for osteoporosis, but its use for screening has not been sufficiently evaluated and more research is needed on cost, accessibility, technical challenges, and sensitivity and specificity. CT could predict fracture occurrence; however, it may be problematic for screening due to cost, exposure to radiation, and availability. Ultrasound was found to predict fracture occurrence with an increased risk of 1.45 (95% confidence interval 1.21–1.73) to fracture. Ultrasound has not replaced DXA as a screening tool for osteoporosis, perhaps due to operator-dependency and difficulty in standardization of testing.

Background: Evidence has been emerging that Helicobacter pylori may also impact colorectal cancer (CRC). Positron emission tomography/computed tomography (PET/CT) imaging can predict overall survival in CRC patients.

Objectives: To determine a possible association between H. pylori seropositivity and all-cause mortality among CRC patients evaluated by PET/CT scans.

Methods: This prospective cohort study was comprised of 110 consecutive CRC patients who had undergone a PET/CT evaluation in a tertiary academic medical center. Data included demographics, body mass index (BMI), tumor node metastasis stage at diagnosis, treatment, time from diagnosis to PET/CT, and PET/CT findings. All patients were tested for anti-H. pylori immunoglobulin G (IgG) antibodies and followed for 36 months from the day of the PET/CT scan. Mortality was documented. Univariate and multivariate Cox regression was used to estimate the hazard ratio (HR) of H. pylori serological status.

Results: During the follow-up period, of the 110 CRC patients 41 (37.3%) died and 69 (62.7%) survived. Of the 41 patients, 26 (63.4%) were H. pylori seropositive and 15 (36.6%) were seronegative. Multivariate analysis showed that H. pylori seropositivity was associated with increased mortality (HR 3.46, 95% confidence interval 1.63–7.32), stage IV at diagnosis, metastatic disease found on PET/CT, longer time from diagnosis to PET/CT, lower BMI, and older age.

Conclusions: Our findings suggest that H. pylori infection may be a risk factor for all-cause mortality among CRC patients who are evaluated by PET/CT. Multicenter studies with larger patient groups are needed to confirm our findings.

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: Virtual autopsies by computer tomography (CT) or magnetic resonance imaging can be valuable in cases of unexplained infant death. The radiologist must be familiar with the normal appearance of all the segments of the thoracic aorta in normal and deceased children. A thorough review of the literature revealed no prior articles describing CT changes in the ascending aorta or the aortic arch in pediatric virtual autopsies.

Objectives: To compare the CT appearance of the thoracic aorta in deceased children and in those younger than 3 years of age.

Methods: Hospital registries were searched for cases of unexpected deaths in children younger than 3 years old, with a postmortem CT available, as well as for clinically indicated chest CT in children of the same age during a 5 year period. The ascending aorta (AA), aortic arch (arch), and the descending aorta (DA) diameters were measured. Student's t-tests and Mann–Whitney U-tests were used to compare the two groups.

Results: A total of 64 scans were reviewed: 35 postmortem and 29 performed on living patients. The differences in the diameter and the ratios of the diameter between the AA and the arch, as well as between the arch and the DA in the postmortem and living groups were statistically significant (P < 0.05).

Conclusions: On postmortem CT scans, we found focal tapering of the aortic caliber at the level of the arch between the origin of the brachiocephalic artery and left subclavian artery. This finding should not be misinterpreted as a hypoplastic aortic arch.