Stensen's Duct Dynamic Anatomy Assessed with Sialography.

Objectives: The presence of a catheter required for contrast infusion during sialography obscures imaging of the distal duct. Static imaging via cone beam computed tomography and magnetic resonance sialography fails to address changes that occur dynamically to the anatomy of the flexible salivary ductal system. We aim to identify dynamic changes to the parotid gland by introducing a novel approach to analyze the full extent of Stensen's duct based on dynamic infusion digital sialography. Methods: Retrospective chart review of a single-center consecutive series of 409 parotid sialograms performed between April 2008 and June 2023 permitted selection of a contemporary series including seven normal sialograms and seven sialograms with stricture(s). Dynamic (fluoroscopic) infusion (iopamidol/gadolinium) sialograms were assessed through blinded review by two radiologists employing the institution's picture archiving and communication (PACS) system (©2023 Koninklijke Philips N.V., Amsterdam, Netherlands). Measurements determined changes, in two dimensions, to the angle of the masseteric bend and duct length while the catheter was in place (repose), during catheter withdrawal (stretch), and during recoil after withdrawal. Differences in median lengths and angles of Stensen's duct between the three time points were compared using Wilcoxon matched-pairs signed rank and Mann-Whitney tests. Results: Fourteen patients [median age (IQR), 55 years (24.7); 10 women] were evaluated. The median angle of the masseteric bend was 117.7° in repose versus 155.4° during catheter withdrawal (P < .001, n = 14). The median distance measured from the Stensen's duct orifice to the first major ductal bifurcation was 81.5 mm (IQR = 12.3) in repose. The median percent increase in length from repose to stretch was 6.3% (P < .001, n = 14). Conclusions: Dynamic infusion digital sialography with fluoroscopic recording during catheter removal permits assessment of the distal duct unobstructed by the presence of a catheter. The technique also identifies the dynamic nature and varying length and angulation of Stensen's duct.

Gadolinium as a contrast agent for infusion sialograms in patients with iodine allergy.

Objectives: To assess the adequacy of gadolinium in sialography as an alternative contrast agent for patients with iodine allergies. To directly compare images taken with gadolinium versus iodine-based contrast agents using the Iowa Sialography Classification System. Methods: Retrospective chart review was performed on patients undergoing sialography between February 2008 and July 2022. Patients with sialograms obtained with gadolinium were identified and matched to similar sialograms obtained with iodine-based contrast agent. Patients were matched based on duct location, duct side, and initial radiology findings. Blinded reevaluation of sialograms was performed first independently and then by consensus by two head and neck radiologists to evaluate overall image adequacy and grade using the Iowa Sialography Classification System. Results: Four patients with six sialograms (one bilateral parotid and one parotid + submandibular) obtained with gadolinium were identified and reevaluated. Five patients with six sialograms (one bilateral parotid) obtained with iodine-based were matched to the gadolinium sialograms. The overall adequacy of images for gadolinium sialograms was graded at an average of 4.25 (4 = good and 5 = excellent); whereas, the overall adequacy of iodine-based sialograms was graded at an average of 5. Inter-observer variability was observed in three sialograms obtained with gadolinium (50%), while no interobserver variability was observed in sialograms obtained with iodine-based contrast agent. Conclusion: Gadolinium is an adequate alternative to use in sialography for patients with iodine allergies undergoing contemporary digital infusion sialography. Adverse reactions to iodine contrast agents are rare in sialography; however, the precautionary use of gadolinium is acceptable for the diagnostic and therapeutic benefits in sialography.Level of Evidence: IV.

Conventional and MR-sialography of accessory submandibular glands: A case report.

Our review of the literature shows anatomical variation of the submandibular gland is a rare entity, unlike the variation that can be seen in parotid glands. Specifically, bilateral submandibular abnormality has only been reported on one occasion with limited imaging in our review. We report a 78-year-old female with a history of sialadenitis and sialolithiasis who presents with swelling and pain in the right submandibular gland. Sialography of the right submandibular gland disclosed a second primary duct branching off the main duct to a second submandibular gland. Cannulation of the left submandibular duct was unsuccessful due to scarring of the duct orifice; however, subsequent MR sialography identified marked submandibular duct dilation and the incidental finding of a second anteriorly located left submandibular gland. The anatomic detail provided by conventional digital sialography is contrasted to the useful but less-defined imaging provided by MR sialography. To our knowledge, this is the first reported case of bilateral accessory submandibular glands that has been evaluated using both conventional and MR sialography.

Ultrasound and Sialogram Correlates to Parotid Immunoglobulin G4-Related Disease.

Immunoglobulin G4 (IgG4)-related disease is an immune-mediated disorder that commonly manifests in the salivary glands. As a recently described disorder, the description and classification of IgG4-related disease is an ongoing process. Diagnosis of IgG4-related disease requires integration of clinical history, histopathology, and radiographic findings, including ultrasonography and sialography. In this case report, we correlate parotid ultrasonographic and sialographic findings in a patient with proven IgG4-related disorder confirmed from analysis of previous submandibular gland resections. We aim to highlight the utility of multimodality imaging in the diagnosis of IgG4-related disease.

Sialographic Analysis of Radioiodine-Associated Chronic Sialadenitis.

OBJECTIVES/HYPOTHESIS: To apply a novel sialography classification system to identify parotid and submandibular ductal findings following I-131 therapy and to assess correlates to dose and duration of symptoms. STUDY DESIGN: Retrospective single-center case series. METHODS: Patients who underwent sialography between February 2008 and February 2019 after previously receiving I-131 treatment were identified via a retrospective chart review. Their sialograms were systematically evaluated and scored by applying the Iowa parotid sialogram scale to also include submandibular gland analysis. RESULTS: From 337 sialograms, 30 (five submandibular, 25 parotid) underwent analysis. Ductal stenosis was identified in all sialograms and was graded as moderate (>50%-75%) in 7/30 cases and severe (>75%) in 15/30 cases. The distal (main) duct was narrowed in 23/30 cases. No association was identified between degree of ductal stenosis and I-131 dose (P = .39), age (P = .81), or time from I-131 therapy to sialogram (P = .97). CONCLUSIONS: The Iowa parotid sialogram scale was successfully applied to report abnormalities of the parotid and submandibular ductal system. The most common manifestation of I-131-associated sialadenitis was a severe stenosis within the distal salivary duct. No statistically significant association was found between degree of ductal stenosis and dose of I-131, age, or duration of symptoms. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1450-E1456, 2021.

Intraoperative Shoulder Traction as Cause of C5 Palsy: Magnetic Resonance Imaging Study.

OBJECTIVE: During surgery, shoulder traction is often used for better fluoroscopic imaging of the lower cervical spine. Traction on the C5 root has been implicated as a potential cause of C5 palsy after cervical spine surgery. Using magnetic resonance imaging, this study was undertaken to determine the impact of upper extremity traction on the C5 root orientation. METHODS: In this study, 5 subjects underwent coronal magnetic resonance imaging of the cervical spine and left brachial plexus. Using a wrist restraint, sequential traction on the left arm with 10, 20, and 30 lb. was applied. Measurements of the angle between the spinal axis and C5 nerve root and the angle between the C5 nerve root and the upper trunk of the brachial plexus were obtained. The measurements were taken by a trained neuroradiologist and analyzed for significance. RESULTS: The angle between the C5 nerve root and the vertical spinal axis remained within 3 and 4 degrees of the mean and was not found to be associated with increased traction weight (P = 0.753). The angle between the C5 root and the upper trunk increased with increasing weight and was found to be statistically significant (P = 0.003). CONCLUSIONS: While the cause of C5 palsy is likely multifactorial, this study provides evidence that, in the awake volunteer, upper extremity traction leads to C5 root and upper trunk tension. These results suggest that shoulder traction in the anesthetized patient could lead to tension of the C5 nerve root and subsequent injury and palsy.

Pneumoparotitis as a complication of long-term oronasal positive airway pressure for sleep apnea.

BACKGROUND: Parotid swelling is rarely caused by pneumoparotitis from retrograde insufflation of air into Stensen's duct. Previous reports have identified occupational exposures, self-induced habits, exercise, spirometry, and short-term positive pressure airway ventilation as causes of salivary duct insufflation. METHODS: We present 2 cases of pneumoparotitis in patients on long-term oronasal continuous positive airway pressure (CPAP) for obstructive sleep apnea. RESULTS: A diagnosis of pneumoparotitis was made by CT scan in case 1 and sialography in case 2. Patients were advised to transition from oronasal to nasal-only CPAP. One patient was successfully transferred and had good symptomatic improvement, whereas the second patient did not tolerate nasal CPAP and had persistent symptoms on oronasal CPAP. CONCLUSION: Long-term use of oronasal CPAP is a potential cause of pneumoparotitis.

Interobserver and intermodality variability in GTV delineation on simulation CT, FDG-PET, and MR Images of Head and Neck Cancer.

PURPOSE: To compare the interobserver and intermodality differences in image-based identification of head and neck primary site gross tumor volumes (GTV). Modalities compared include: contrast-enhanced CT, F-18 fluorodeoxyglucose positron emission tomography (PET/CT) and contrast-enhanced MRI. METHODS AND MATERIALS: Fourteen patients were simulated after immobilization for all 3 imaging modalities (CT, PET/CT, MRI). Three radiation oncologists (RO) contoured GTVs as seen on each modality. The GTV was contoured first on the contrast-enhanced CT (considered the standard), then on PET/CT, and finally on post-contrast T1 MRI. Interobserver and intermodality variability were analyzed by volume, intersection, union, and volume overlap ratio (VOR). RESULTS: Analysis of RO contours revealed the average volume for CT-, PET/CT-, and MRI-derived GTVs were 45cc, 35cc and 49cc, respectively. In 93% of cases PET/CT-derived GTVs had the smallest volume and in 57% of cases MRI-derived GTVs had the largest volume. CT showed the largest variation in target definition (standard deviation amongst observers 35%) compared to PET/CT (28%) and MRI (27%). The VOR was largest (indicating greatest interobserver agreement) in PET/CT (46%), followed by MRI (36%), followed by CT (34%). For each observer, the least agreement in GTV definition occurred between MRI & PET/CT (average VOR = 41%), compared to CT & PET/CT (48%) and CT & MRI (47%). CONCLUSIONS: A nonsignificant interobserver difference in GTVs for each modality was seen. Among three modalities, CT was least consistent, while PET/CT-derived GTVs had the smallest volumes and were most consistent. MRI combined with PET/CT provided the least agreement in GTVs generated. The significance of these differences for head & neck cancer is important to explore as we move to volume-based treatment planning based on multi-modality imaging as a standard method for treatment delivery.

Craniofacial osteoma: clinical presentation and patterns of growth.

BACKGROUND: This study was designed to investigate the clinical features and the growth rate of craniofacial osteomas. METHODS: Retrospective chart review was performed of 200 cases of craniofacial osteomas diagnosed from January 2001 to September 2011. Data pertinent to patient and osteoma lesion characteristics were collected. Histology of operated cases was reviewed. Computer tomography (CT) charts were reviewed and those with multiple images were analyzed for growth characteristics. RESULTS: One hundred forty-nine patients met our inclusion criteria. Eighty-nine percent of these osteomas were found incidentally. Forty-three percent were in the frontal sinus. Fifteen percent of the patients complained of headaches and only 6.71% of patients with osteoma had headaches congruent with osteoma location. Thirty-one percent of CT scans had sinus mucosal disease; only 8% had mucosal disease adjacent to the osteoma. Ten of the 149 patients underwent surgery for cosmetic and/or rapidly growing osteomas. Thirteen patients had intestinal tubular adenoma, and one was genetically positive for Gardner's syndrome. Fifty-two patients had multiple CT scans that were included in growth rate analysis. The mean linear growth rate of osteomas was estimated to be 0.117 mm/yr (95% CI, 0.004, 0.230) in maximal dimension, assuming linear growth. A descriptive analysis of osteoma growth divided the osteomas into several intervals and studied the growth rate separately in each interval. The median change in maximum dimension was different in each interval in a nonsystematic manner, ranging from -0.066 mm, over 3- to 9-month interval (interquartile range [IQR] = -0.404-1.069), to 0.369 mm over 9- to 15-month interval (IQR = -0.032-0.855), and 0.082 mm over 45- to 51-month interval (IQR = -0.000-0.197). There was no significant association between tumor size, location, or complications. CONCLUSION: Craniofacial osteomas are slow-growing lesions with no specific growth pattern and rare complications. Their clinical behavior is ill defined and justifies a conservative approach toward asymptomatic lesions with close radiological follow-up.

Request form history, clinical indication, and yield of brain magnetic resonance studies.

PURPOSE: To investigate whether improved clinical history allows the radiologist to better predict the pretest probability of obtaining a positive or negative result from a magnetic resonance (MR) examination. MATERIALS AND METHODS: Six neuroradiologists prospectively reviewed 100 consecutive requests for brain MR examinations and sequentially assessed 1) quality of written history, 2) degree of indication for requested study, and 3) any pertinent new information found during chart review that may have altered the degree of indication. MR yield was correlated with the degree of indication assessed before and after chart review. RESULTS: Most request form histories were judged as poor (63%), and chart review reduced the overall indications for MR examinations, as there was a tendency for high-indication requests to migrate to the low-indication category. Based on request form history alone, the yields for low- and high-indication studies were 13% and 37%, respectively. Correlations between MR yield and indication after chart review improved significantly (P < 0.05) with 2% and 61% for low and high indications, respectively. Sensitivity and specificity for a positive MR yield were 71% and 62%, respectively, for the indication judged by the request history alone, and 96% and 80%, respectively, after chart review. Positive and negative prediction rates were 37% and 87%, respectively, for the indication judged by the request history alone, and 61% and 98%, respectively, for the indication judged after chart review. CONCLUSION: Based on our limited data, most request form histories were inadequate, and essential information available in the chart before MR examinations was frequently missing from the request forms. When adequate information was provided, the indication for the studies as judged by the radiologists predicted the MR yield more accurately, particularly for those requests with low indication. Therefore, our study suggests that MR imaging (MRI) may be used more effectively when pertinent clinical history is available. However, our study is limited and further studies are needed to confirm our results.

Radiology residency eCurriculum developed in-house: evaluation of benefits and weaknesses.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate residents' use of a radiology curriculum CD-ROM designed to provide ready access to the department's curricula, study materials, and Internet resources. MATERIALS AND METHODS: A survey questionnaire eliciting feedback about the usability and value of the CD-ROM, as well as suggestions for future modifications in its content, was distributed to radiology residents (n = 26) in the authors' training program. Twenty-three (88%) of the residents responded to the survey. RESULTS: Eighteen (78%) of the 23 respondents reported having used the CD-ROM at least once, and 22 (96%) considered the CD-ROM an asset to the residency program. Fourteen (61%) identified the centralization of important information as the greatest benefit of the CD-ROM. Nonetheless, a majority continued to rely on more traditional methods of obtaining information essential to their work and studies. Twelve (52%) of the 23 residents reported that daily use of the material stored on the CD-ROM would be encouraged by placing it on a departmental intranet, while seven (30%) preferred the addition of dedicated computers and the provision of study space in the department. CONCLUSION: The CD-ROM has not been fully integrated into the residency program. The greatest obstacle to its use is the lack of computer resources in the department.

Qualitative assessment of cervical spinal stenosis: observer variability on CT and MR images.

BACKGROUND AND PURPOSE: Several studies have been undertaken to validate quantitative methods of evaluating cervical spinal stenosis. This study was performed to assess the degree of interobserver and intraobserver agreement in the qualitative evaluation of cervical spinal stenosis on CT myelograms and MR images. METHODS: Cervical MR images and CT myelograms of 38 patients were evaluated retrospectively. Six neuroradiologists with various backgrounds and training independently assessed the level, degree, and cause of stenosis on either MR images or CT myelograms. Unknown to the evaluators, 16 of the patients were evaluated twice to determine intraobserver variability. RESULTS: Interobserver agreement among the radiologists with regard to level, degree, and cause of stenosis on CT myelograms showed kappa values of 0.50, 0.26, and 0.32, respectively, and on MR images showed kappa values of 0.60, 0.31, and 0.22, respectively. Intraobserver agreement with regard to level, degree, and cause of stenosis on CT myelograms showed mean kappa values of 0.69, 0.41, and 0.55, respectively, and on MR images showed mean kappa values of 0.80, 0.37, and 0.40, respectively. CONCLUSION: MR imaging and CT myelographic evaluation of cervical spinal stenosis by using current qualitative methods results in significant variation in image interpretation.