Israel Medical Association Journal

Background: Management of patients with reported iodinated contrast media (ICM) allergy is not supported by sufficient data. It is assumed that these patients are at risk for severe reactions, and that premedication provides protection.

Objective: To examine current practice and prognosis in hospitalized patients with ICM allergy.

Methods: In this retrospective study, we analyzed data of 17,356 patients who were hospitalized between 2018 and 2022 and referred for imaging. No-allergy and allergy groups were matched by age, sex, co-morbidities, and indications for imaging. Statistical analysis compared demographic, clinical, and imaging-related parameters.

Results: Our study included records of 501 patients with ICM allergy and 16,855 with no allergy. Patients with allergy were older (70.92 ± 16.25 vs. 59.02 ± 23.74 years, P < 0.001), female preponderance (male proportion 42.5% vs. 54%, P < 0.001), and those with increased cardiovascular and metabolic co-morbidities. The rate of ICM injection was similar among patients with ICM allergy (34%) and no allergy (36%). Most patients with ICM allergy did not receive premedication. Allergic patients demonstrated increased mortality (25.9% vs. 16.5%, P < 0.001); however, this result was not associated with the diagnosis of allergy, anaphylactic reactions, or premedication.

Conclusions: ICM allergy is mostly reported in patients with advanced age and multiple co-morbidities. Mortality was not increased when compared to matched non-allergic individuals. Among patients with reported allergy who were injected with ICM, anaphylaxis was not a cause of death, although fewer than half received premedication. Prospective trials are warranted to revise the clinical approach to ICM allergy.

Background: Cloacal malformation represents the rarest and most complex congenital anorectal malformation in females and is characterized by the convergence of urinary, gynecological, and intestinal systems within a single common channel. Three-dimensional computed tomography reconstruction (3D CT cloacagram) has emerged as a valuable method for anatomical assessment and preoperative planning.

Objectives: To evaluate our experience with 3D CT cloacagram and assess its results.

Methods: This retrospective case series included all patients with cloacal malformation who underwent preoperative 3D CT cloacagram at a single institution during 2019–2023. Collected data included patient characteristics, timing of the 3D CT cloacagram, results of the 3D CT cloacagram, comparison with endoscopic results, surgical procedures, and postoperative outcome.

Results: Six patients with cloacal malformation were included in this study, including two with posterior cloaca. The median common channel length on 3D CT cloacagram was 24.5 mm (range 9–48 mm) and the median urethral length was 15.5 mm (range 13-24 mm). The surgical approach involved a combined abdominoperineal approach in three patients and posterior sagittal anorectal vaginal urethral plasty in one patient. Two patients were awaiting surgical reconstruction at the time of publication.

Conclusions: Our implementation of 3D cloacagram has facilitated precise measurements of both the urethra and common channel lengths, two key factors in formulating surgical strategies for cloacal reconstruction. Moreover, this technique has markedly improved our capacity for surgical planning contributing to colorectal, gynecological, and urological perspectives.

Background: Computed tomography (CT) is the main diagnostic modality for detecting pancreatic adenocarcinoma.

Objectives: To assess the frequency of missed pancreatic adenocarcinoma on CT scans according to different CT protocols.

Methods: The medical records of consecutive pancreatic adenocarcinoma patients were retrospectively collected (12/2011–12/2015). Patients with abdominal CT scans performed up to a year prior to cancer diagnosis were included. Two radiologists registered the presence of radiological signs of missed cancers. The frequency of missed cancers was compared between portal and pancreatic/triphasic CT protocols.

Results: Overall, 180 CT scans of pancreatic adenocarcinoma patients performed prior to cancer diagnosis were retrieved; 126/180 (70.0%) were conducted using pancreatic/triphasic protocols and 54/180 (30.0%) used portal protocols. The overall frequency of missed cancers was 6/180 (3.3%) in our study population. The frequency of missed cancers was higher with the portal CT protocols compared to the pancreatic/triphasic protocols: 5/54 (9.3%) vs. 1/126 (0.8%), P = 0.01. CT signs of missed cancers included small hypodense lesions, peri-pancreatic fat stranding, and dilated pancreatic duct with a cut-off sign.

Conclusions: The frequency of missed pancreatic adenocarcinoma is higher on portal CT protocols. Physicians should consider the cancer miss rate on different CT protocols.

Recent studies using propensity score matching have clearly indicated that contrast nephropathy following computed tomography occurs in hospitalized patients with advanced chronic kidney disease (eGFR < 30 ml/min/1.73 m²) and that this iatrogenic complication is likely underestimated because of concomitant renal functional recovery, unrelated to the imaging procedure. These findings should be considered regarding contrast-enhanced studies in such patients.

Fever of unknown origin (FUO) is defined as the repeated occurrence of elevated body temperature above 38.3°C (101°F) lasting for at least 3 weeks with no clear diagnosis despite a thorough investigation of more than one-week duration. FUO cases could be categorized into three major etiologies: infectious, neoplastic, and systemic inflammatory. Despite novel diagnostic modalities, clinicians still encounter a significant number of unresolved FUO cases, accounting for as many as 50% of cases [1]. Prolonged futile FUO investigations may be a source of frustration for many clinicians [2]. We described a unique cause for FUO that shares the complexity of the diagnostic workup and emphasizes the importance of ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (PET/CT) modality in the process of investigating FUO.

Background: Unilateral intratonsillar abscess (ITA) is an underreported, well-known complication of acute tonsillitis. The prevalence of unilateral ITA compared to peritonsillar abscess (PTA) is 1:14. However, bilateral ITA is an extremely rare entity, with only four cases reported thus far.

Objectives: To describe past cases and our experience, elaborating the diagnostic challenge and the surgical treatment for bilateral ITA.

Methods: We conducted a literature search in the PubMed database using the key words intra-tonsillar abscess, tonsillar abscess, bilateral tonsillar abscess, bilateral intra-tonsillar abscess and bilateral peritonsillar abscess. Our search was limited to the years 1980 to 2020.

Results: We found that only four cases of bilateral ITA were previously published. All were characterized by a delay in diagnosis with a median of 10 days (4–14 days), symmetrical oral cavity appearance, enlarged bilateral kissing tonsils, and subsequent treatment by surgical drainage/paracentesis. Respiratory compromise was a concern in most cases. Our patient was treated with bilateral quinsy tonsillectomy and had a prompt recovery.

Conclusions: Bilateral ITA is a rare, deceiving entity, with a diagnosis delay attributed to the symmetrical oral bulging. We present the fifth case reported and the first ever reported in a pediatric patient. We describe the assumed pathogenesis and the main characteristics among all five patients, emphasizing the important role of a high index of suspicion and appropriate imaging, guiding to proper diagnosis and treatment.

Mesenteric venous thrombosis (MVT) refers to acute, subacute, or chronic thrombosis and occlusion of the mesenteric veins. MVT is an uncommon disorder, with an estimated incidence of is 2.7 per 100,000 patient-years. It accounts for 1 in 5000 to 15,000 inpatient admissions [1,2].

Background: The current approach to performing sacral neuromodulation consists of a two-stage procedure, the first of which includes insertion of the sacral electrode under fluoroscopic visualization of the S3 foramen. Alternatively, in certain situations computed tomography (CT)-guided insertion can be used.

Objectives: To evaluate the use of CT in cases of reinsertion of the electrode due to infection, dislocation, or rupture.

Methods: Medical records of patients who underwent neuromodulation device reinsertion between 2005 and 2016 for fecal incontinence were reviewed. Study outcomes included procedure course, successful placement, and long-term treatment success.

Results: During the study period, we inserted a neuromodulation device in 67 patients. A CT-guided insertion of a sacral electrode was performed in 10 patients. In nine patients, the insertion and the final location of the electrode were successful. In one patient, the electrode migrated upward due to a malformation of the S3 foramen on both sides and had to be placed in S4. In a mean follow-up of 68.4 ± 30.0 months following the re-insertion, there was a significant reduction in the number of incontinence episodes per day (P < 0.001) and the number of pads used per day (P = 0.002).

Conclusions: CT-guided insertion of a sacral electrode is a safe and promising option, especially in recurrent and or selected cases

Background: For locally advanced rectal cancer patients a watch-and-wait strategy is an acceptable treatment option in cases of complete tumor response. Clinicians need robust methods of patient selection after neoadjuvant chemoradiation.

Objectives: To predict pathologic complete response (pCR) using computer vision. To analyze radiomic wavelet transform to predict pCR.

Methods: Neoadjuvant chemoradiation for patients with locally advanced rectal adenocarcinoma who passed computed tomography (CT)-based simulation procedures were examined. Gross tumor volume was examind on the set of CT simulation images. The volume has been analyzed using radiomics software package with wavelets feature extraction module. Statistical analysis using descriptive statistics and logistic regression was performed was used. For prediction evaluation a multilayer perceptron algorithm and Random Forest model were used.

Results: In the study 140 patients with II–III stage cancer were included. After a long course of chemoradiation and further surgery the pathology examination showed pCR in 38 (27.1%) of the patients. CT-simulation images of tumor volume were extracted with 850 parameters (119,000 total features). Logistic regression showed high value of wavelet contribution to model. A multilayer perceptron model showed high predictive importance of wavelet. We applied random forest analysis for classifying the texture and predominant features of wavelet parameters. Importance was assigned to wavelets.

Conclusions: We evaluated the feasibility of using non-diagnostic CT images as a data source for texture analysis combined with wavelets feature analysis for predicting pCR in locally advanced rectal cancer patients. The model performance showed the importance of including wavelets features in radiomics analysis.

Background: Medical imaging and the resultant ionizing radiation exposure is a public concern due to the possible risk of cancer induction.

Objectives: To assess the accuracy of ultra-low-dose (ULD) chest computed tomography (CT) with denoising versus normal dose (ND) chest CT using the Lung CT Screening Reporting and Data System (Lung-RADS).

Methods: This prospective single-arm study comprised 52 patients who underwent both ND and ULD scans. Subsequently AI-based denoising methods were applied to produce a denoised ULD scan. Two chest radiologists independently and blindly assessed all scans. Each scan was assigned a Lung-RADS score and grouped as 1 + 2 and 3 + 4.

Results: The study included 30 men (58%) and 22 women (42%); mean age 69.9 ± 9 years (range 54–88). ULD scan radiation exposure was comparable on average to 3.6–4.8% of the radiation depending on patient BMI. Denoising increased signal-to-noise ratio by 27.7%. We found substantial inter-observer agreement in all scans for Lung-RADS grouping. Denoised scans performed better than ULD scans when negative likelihood ratio (LR-) was calculated (0.04–-0.08 vs. 0.08–0.12). Other than radiation changes, diameter measurement differences and part-solid nodules misclassification as a ground-glass nodule caused most Lung-RADS miscategorization.

Conclusions: When assessing asymptomatic patients for pulmonary nodules, finding a negative screen using ULD CT with denoising makes it highly unlikely for a patient to have a pulmonary nodule that requires aggressive investigation. Future studies of this technique should include larger cohorts and be considered for lung cancer screening as radiation exposure is radically reduced.

Background: Multiple myeloma (MM) affects the long bones in 25% of patients. The advent of positron-emission tomography/computed tomography (PET/CT) scanners offers the possibility of both metabolic and radiographic information and may help determine fracture risk. To the best of our knowledge, no published study correlates these two factors with long bone fractures.

Objective: To evaluate the impact of PET/CT on fracture risk assessment in multiple myeloma patients.

Methods: We identified all bone marrow biopsy proven multiple myeloma patients from 1 January 2010 to 31 January 2015 at a single institution. We prospectively followed patients with long bone lesions using PET/CT scan images.

Results: We identified 119 patients (59 males/60 females) with 256 long bone lesions. Mean age at diagnosis was 58 years. The majority of lesions were in the femur (n=150, 59%) and humerus (n=84, 33%); 13 lesions in 10 patients (8%) required surgery for impending (n=4) or actual fracture (n=9). Higher median SUVmax was measured for those with cortical involvement (8.05, range 0–50.8) vs. no involvement (5.0, range 2.1–18.1). SUVmax was found to be a predictor of cortical involvement (odds ratio = 1.17, P = 0.026). No significant correlation was found between SUVmax and pain or fracture (P = 0.43).

Conclusions: Improved medical treatment resulted improvement in 8% of patients with an actual or impending fracture. The orthopedic surgeons commonly use the Mirels classification for long bone fracture prediction. Adding PET/CT imaging to study in myeloma long bone lesions did not predict fracture risk directly but suggested it indirectly by cortical erosion.

Background: Recommendations for a head computed tomography (CT) scan in elderly patients without a loss of consciousness after a traumatic brain injury and without neurological findings on admission and who are not taking oral anticoagulant therapy, are discordant.

Objectives: To determine variables associated with intracranial hemorrhage (ICH) and the need for neurosurgery in elderly patients after low velocity head trauma

Methods: In a regional hospital, we retrospectively selected 206 consecutive patients aged ≥ 65 years with head CT scans ordered in the emergency department because of low velocity head trauma. Outcome variables were an ICH and neurological surgery. Independent variables included age, sex, disability, neurological findings, facial fractures, mental status, headache, head sutures, loss of consciousness, and anticoagulation therapy.

Results: Fourteen patients presented with ICH (6.8%, 3.8–11.1%) and three (1.5%, 0.3–4.2%) with a neurosurgical procedure. One patient with a coma (0.5, 0.0–2.7) died 2 hours after presentation. All patients who required surgery or died had neurological findings. Reducing head CT scans by 97.1% (93.8–98.9%) would not have missed any patient with possible surgical utility. Twelve of the 14 patients (85.7%) with an ICH had neurological findings, post-trauma loss of consciousness or a facial fracture were not present in 83.5% (95% confidence interval 77.7–88.3) of the cohort.

Conclusions: None of our patients with neurological findings required neurosurgery. Careful palpation of the facial bones to identify facial fractures might aid in the decision whether to perform a head CT scan.