Imaging Features and Complications of Facial Cosmetic Procedures.

Facial aesthetic procedures have become increasingly popular and complex, making knowledge of facial anatomy crucial for achieving desired outcomes without complications. Some of the most common procedures include blepharoplasty, bichectomy, face-lifts, facial implants, thread lifting, and fillers. Blepharoplasty and bichectomy are surgical procedures that respectively aim to restore youthful contours to the periorbita and create a slimmer lower face by removing Bichat fat from the maxillofacial region. Facial implants are used for aesthetic augmentation of the skeletal structure and restoration of facial contour by using biomaterials or autogenous bone grafts. Face-lift surgeries involve incisions and removal of excess skin, and thread lifts involve less invasive procedures performed by inserting threads beneath the skin, with the aim to lift the skin and thus reduce wrinkles and sagging. Fillers improve wrinkles and loss of facial volume, with biologic types made from animal, human, or bacterial sources (such as hyaluronic acid), while synthetic fillers include substances such as paraffin, silicone, calcium hydroxyapatite, polymethylmethacrylate microspheres, polyacrylamide hydrogel, hydroxyethyl-ethyl methacrylate, and poly-l-lactic acid. Synthetic fillers can be classified as rapidly resorbable (<12 months), slowly resorbable (<24 months), or permanent. Imaging modalities such as US, CT, and MRI can help identify and analyze each type of facial aesthetic procedure or filler, as well as their possible complications such as foreign-body granuloma, noninflammatory nodule, late intermittent persistent edema, filler migration, infection, or complications after removal of the buccal fat pad. ©RSNA, 2023 Quiz questions for this article are available through the Online Learning Center The online slide presentation from the RSNA Annual Meeting is available for this article.

Reassessing the Anatomic Origin of the Juvenile Nasopharyngeal Angiofibroma.

OBJECTIVE: A modern imaging review is necessary to further define the anatomic origin of the juvenile nasopharyngeal angiofibroma. METHODS: After institutional review board approval, a search from January 1998 to January 2013 yielded 33 male patients (aged 10-23 years) with pathologically proven juvenile nasopharyngeal angiofibroma lesions, as well as pretreatment computed tomography/magnetic resonance imaging. Juvenile nasopharyngeal angiofibroma involvement was assessed in the following regions: sphenopalatine foramen, pterygopalatine fossa, vidian canal, nasopharynx, nasal cavity, sphenoid sinus, choana, pterygomaxillary fissure/masticator space, orbit, and sphenoid bone. RESULTS: The choana and nasopharynx were involved in all 33 patients. In contrast, only 22 lesions involved the pterygopalatine fossa, 24 lesions involved the sphenopalatine foramen, and 28 lesions involved the vidian canal. CONCLUSIONS: Our results suggest that the juvenile nasopharyngeal angiofibroma origin is in the region of the choana and nasopharynx rather than the sphenopalatine foramen or pterygopalatine fossa.

The prevalence of superior semicircular canal dehiscence in conductive and mixed hearing loss in the absence of other pathology using submillimetric temporal bone computed tomography.

OBJECTIVE: The objective of this study was to assess the relationship between superior semicircular canal dehiscence (SSCD) and hearing impairment. METHODS: We retrospectively compared the prevalence of SSCD in the ears classified as conductive hearing loss (CHL), mixed hearing loss (MHL), and normal hearing status using submillimetric temporal bone computed tomography (TBCT) on the basis of coronal and additional reformatted planes dedicated to SSCD. RESULTS: From the patients with CHL (n = 127) and MHL (n = 45), the overall prevalence of SSCD in the ears classified as CHL, MHL, and normal hearing status were 6.6%, 7.2%, and 3.0%, respectively. Furthermore, the odds ratio for SSCD in the absence of any cause of hearing loss (eg, dysfunction of the tympanic membrane or middle ear, TBCT abnormalities, otosclerosis, trauma, surgery) was 5.35 in MHL (4/27; P = 0.037, 95% confidence interval, 1.1-25.81) and 3.31 in CHL (5/61; P = 0.115, 95% confidence interval, 0.75-14.63), compared with normal hearing status. CONCLUSIONS: Bony covering of the SSC should be specifically evaluated in patients with hearing impairment using submillimetric TBCT.

Calcified cystic lesion in cerebellum: A case report.

Intracranial epidermoid cysts are benign, slow-growing congenital tumors of ectodermal origin. They are rare embryonal benign cystic masses with an incidence rate of approximately 0.04%-0.6% of intracranial tumors. Computed tomography (CT) and magnetic resonance imaging (MRI) are fundamental diagnostic tools providing valuable information for surgical management. We reported a 59-year-old male patient with right limb weakness twelve hours prior to admission, slurred speech, and paresis of the facial nerve. Based on history taking, physical examination, and radiology examinations, we concluded a diagnosis of non-communicated hydrocephalus due to a right cerebellar intra-axial tumor with a suspicion of low-grade glioma (Pylocitic Astrocytoma). CT and MRI in intracranial epidermoid cysts are fundamental diagnostic tools for diagnosing and obtaining helpful information for surgical planning. Intracranial epidermoid cysts appear as lobulated lesions filling and expanding CSF spaces and exerting a gradual mass effect, insinuating between structures and encasing adjacent nerves and vessels. In this case, we noted a hypodense lesion with irregular calcifications and well-defined on the right cerebellar region measuring 6.15 × 5.47 × 5.7 cm, surrounded by a hypodense image suggesting an intra-axial mass suspected of low-grade glioma with a differential diagnosis of brain abscess. The hypointense lesion on the T1WI sequence found in the MRI examination, with no significant contrast enhancement and restricted diffusion area on DWI, was one of the notable features described in the epidermoid cyst. Intracranial epidermoid cyst rarely occurs in the intracranial, resulting in many symptoms in this case, which should be diagnosed and treated promptly. Imaging aids in proper diagnosis and provides more valuable information for further treatment.

Utility of dual-energy CT virtual keV monochromatic series for the assessment of spinal transpedicular hardware-bone interface.

OBJECTIVE: Our aim was to evaluate the utility of dual-energy CT (DECT) virtual kilo-electron volt (keV) monochromatic images for the visualization of the transpedicular screw-bone interface after spinal fusion. MATERIALS AND METHODS: This retrospective study included postfusion spine CT studies performed from October 2011 through April 2012 on a dual-energy 64-MDCT unit (Discovery CT750 HD). Studies were postprocessed on an Advantage Windows workstation (version 4.4) by two neuroradiologists with creation of monochromatic images from 40 to 140 keV. Each reader graded the screw-bone interfaces on the 70-keV images (used for clinical interpretation) and on the monochromatic series using a 5-point scale (1 [uninterpretable] to 5 [excellent]). The grades of the interfaces were compared using the Wilcoxon signed rank test to detect differences between the 70-keV image and the monochromatic series. RESULTS: Ninety-two transpedicular screws in 10 patients were studied. Significant improvement in the visibility of the hardware-bone interface was seen on the monochromatic series compared with the 70-keV images: The median grade for the monochromatic series was 4 (range, 2-5) for both readers, whereas the median grade for the 70-keV images was 3 (range, 2-4) for reader 1 and 2 (range, 2-3) for reader 2 (both, p < 0.001). The interobserver agreement using weighted kappa was 0.51 for grading screw-bone interface visualization. The volume CT dose index was 29.5 mGy in all patients and the mean dose-length product was 805.2 mGy × cm. CONCLUSION: Monochromatic images generated on gemstone spectral DECT are beneficial in the reduction of metallic streak artifact and enable better visualization of the hardware-bone interface than the 70-keV series in patients treated with spinal transpedicular screw fixation.

Differentiation of benign and malignant neck pathologies: preliminary experience using spectral computed tomography.

PURPOSE: The objective of this study was to evaluate spectral Hounsfield unit (HU) curves and effective Z (atomic number) generated on dual-energy gemstone spectral imaging computed tomography (CT) in the differentiation of benign and malignant neck pathologic findings. METHODS: This was a retrospective review of 38 patients who underwent neck CT on a gemstone spectral imaging dual-energy CT (Lightspeed CT750 HD 64-slice CT scanner; GE Medical Systems, Milwaukee, Wis) from November 2009 to June 2012 with identifiable masses. One board-certified radiologist placed regions of interest within the mass (19 benign, 19 malignant) and in paraspinal muscles (PSMs) to create 2 spectral HU curves in each patient. The curve parameters compared between the benign and malignant groups included range (conceptually, the difference between the highest and lowest HU), asymptote, decay, and the differences and ratios (of lesion to PSM) of each of these 3 parameters. A logistic regression model was built with these parameters and effective Z. RESULTS: The difference in ranges (between lesion and PSM) was the best predictor of malignancy, with a threshold of 75 or greater demonstrating 95% sensitivity, 89% specificity, and 91.8% area under the curve (AUC). Adding other spectral HU parameters and effective Z to the model did not substantially increase the AUC (93.3%, difference between the 2 models not statistically significant, P > 0.25). The effective Z showed a 79.9% AUC with 68% sensitivity and 68% specificity at an 8.80 cutoff. CONCLUSIONS: The spectral HU curve is promising for differentiating benign and malignant neck pathologic findings, with the difference in range between the lesion and PSM showing the best predictive value.

Intranodal cystic changes: a potential radiologic signature/biomarker to assess the human papillomavirus status of cases with oropharyngeal malignancies.

OBJECTIVE: The aim of this study was to determine if lymph node imaging findings can predict human papillomavirus (HPV) positivity in oropharyngeal squamous cell cancers. METHODS AND MATERIALS: Pretreatment postcontrast neck computed tomographic scans of 49 patients (male, 35; female, 14; age range, 45-76 years) diagnosed with oropharyngeal malignancies and with available HPV data were retrospectively reviewed. Metastatic lymph nodes were identified based on standardly accepted size and morphological criteria. Various lymph node parameters were studied, including presence of cystic foci in the metastatic lymph nodes, abnormal lymph nodes showing low-attenuation foci, matted lymph nodes, and morphologically normal smaller (<1.5 cm) lymph nodes. These parameters were then independently correlated with the available HPV status of these patients. Finally, an extended criterion, that is, intranodal cystic changes in cases with morphologically normal small (<1.5 cm) lymph nodes, was correlated with HPV status. Sensitivity, specificity, and positive predictive values (PPVs) and negative predictive values (NPVs) were calculated. RESULTS: Of these 49 cases with oropharyngeal cancers, 27 were HPV positive, and 22 cases were HPV negative. Eight cases (3 HPV positive and 5 HPV negative) did not have metastatic lymph nodes. Of remaining 41 cases with metastatic abnormal lymph nodes, 26 were HPV positive, and 15 were HPV negative. Of these 41 cases with metastatic lymph nodes, 14 had 1 or more lymph nodes with cystic foci. Of these 14 cases, 10 (71.4%) were HPV positive. Resultant sensitivity, specificity, PPV, and NPV of cystic foci for the presence of HPV status were 38.4%, 73.3%, 71.4%, and 40.7%, respectively. Intranodal cystic changes in cases with morphologically normal small (<1.5 cm) lymph nodes were found in 5 cases; all 5 were HPV positive. Resultant accuracy was specificity and PPV of 100%, sensitivity of 19.2% and NPV of 41.6%. CONCLUSIONS: Intranodal cystic changes seen on the pretreatment postcontrast neck computed tomographic scan of patients with oropharyngeal malignancies are radiologic signatures strongly associated with the HPV status of the patient. The results in this initial study warrant larger prospective studies to determine if this finding may be used in addition to other molecular biomarkers to help identify those patients who may be amenable to the most appropriate treatment options.

Extraosseous Ewing sarcoma in the fossa jugular: A rare case report.

Background: Extraosseous Ewing sarcoma (EES) is a rare case that accounts for 20% of Ewing sarcoma cases. EES is the second most prevalent pediatric malignancy after peripheral primitive neuroectodermal tumors. EES mostly arise from soft tissue and extra-skeletal. Computed tomography (CT) and magnetic resonance imaging (MRI) are primary modalities for determining tumor location, characteristics, type, and extent of tumors. In addition, for presurgical management, radio intervention with arterial embolization is needed as a preoperative. Case Description: We present a case of a 15-year-old boy diagnosed with EES. He had a "horn-like" tumor that grew progressively on his right ear over 5 months. Head CT scan and MRI were conducted to assess the extent. Embolization was performed before surgery. The surgery was conducted to excise the tumor radically. The histology pathology examination showed EES. Conclusion: EES rarely occurs in the head and neck. This may manifest as a solid mass with bleeding components that destroy the nearby bones, with exophytic mass. Imaging is important for early finding and detecting complications of EES.

Differentiation between germinoma and other pineal region tumors using diffusion-and susceptibility-weighted MRI.

PURPOSE: To evaluate the effectiveness of diffusion-weighted imaging (DWI) and susceptibility-weighted imaging (SWI) for differentiation between germinoma and other pineal region tumors. METHOD: This retrospective study consisted of 72 patients with pathologically proven pineal region tumors between January 2010 and August 2020. Tumors were classified as germinomas (40), non-germinomatous germ cell tumors (11) (NGGCT), pineal parenchymal tumors (10) (PPT), and other types of tumors (11). Visual scale score, ADC values and SWI intratumoral susceptibility signal (ITSS) score were analyzed and compared to histopathology data. RESULTS: The mean apparent diffusion coefficient (ADCmean) and minimum apparent diffusion coefficient (ADCmin) ratio of germinoma were significantly lower than NGGCT. ADCmean or ADCmin cut-off ratio of ≤ 1.48 or ≤ 1.32 allowed for discrimination between germinoma and NGGCT with sensitivity and specificity of 100 % and 63.6 %. An ADCmin cut-off ratio of ≥ 0.93 allowed for discrimination between germinoma and PPT with sensitivity and specificity of 60 % and 80.0 %. ADCmin cut-off ratio of ≤ 1.15 allowed for discrimination of germinoma from other types of tumors with sensitivity and specificity of 87.5 % and 54.5 %. CONCLUSIONS: ADC ratio can differentiate germinoma from other types of pineal region tumors. Our initial results suggest that ITSS score was not significantly correlated with specific histology subtype.

Summary of the 2022 ACR Intersociety Meeting.

The ACR Intersociety Committee meeting of 2022 (ISC-2022) was convened around the theme of "Recovering From The Great Resignation, Moral Injury and Other Stressors: Rebuilding Radiology for a Robust Future." Representatives from 29 radiology organizations, including all radiology subspecialties, radiation oncology, and medical physics, as well as academic and private practice radiologists, met for 3 days in early August in Park City, Utah, to search for solutions to the most pressing problems facing the specialty of radiology in 2022. Of these, the mismatch between the clinical workload and the available radiologist workforce was foremost-as many other identifiable problems flowed downstream from this, including high job turnover, lack of time for teaching and research, radiologist burnout, and moral injury.

Utility of pretreatment mean apparent diffusion coefficient and apparent diffusion coefficient histograms in prediction of outcome to chemoradiation in head and neck squamous cell carcinoma.

PURPOSE: This study aimed to evaluate pretreatment whole-tumor mean apparent diffusion coefficient (ADC) and ADC histogram as predictors of outcome to chemoradiation in patients with head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Patients with HNSCC underwent pretreatment 3-T diffusion-weighted magnetic resonance imaging with calculation of mean ADC and ADC histograms. Outcomes were determined 2 years after chemoradiation. Positive outcome was defined as no abnormal 18-fluoro deoxy glucose uptake on posttherapy computed tomography-positron emission tomography (or abnormal uptake that was proven benign), no locoregional recurrence or metastatic disease, and no requirement for salvage surgery. Negative outcome was defined as residual abnormal 18-fluoro deoxy glucose avidity that was proven malignant, salvage surgery requirement, locoregional recurrence or metastatic disease, death, or a combination of these. A 2-sample t test was used to compare the mean ADC between patients with positive and negative outcomes. The ADC cut point for dividing the groups was determined by looking at its distribution. A Kaplan-Meier plot was produced, and a log-rank test was conducted with calculation of sensitivity, specificity, and positive and negative predictive values. RESULTS: Nine patients showed positive and 8 showed negative outcomes. Significant difference (P = 0.03) was seen in mean ADC (in 10 mm/s) between patients showing positive and negative outcomes (1.18 and 1.43, respectively). According to the log-rank test, tumors with greater than 45% of their volume below the ADC threshold of 1.15 × 10 mm/s were more likely to have a positive outcome (accuracy, 77%). CONCLUSIONS: Patients with HNSCC demonstrating lower pretreatment ADC and with greater than 45% of volume below ADC threshold of 1.15 × 10 mm/s may have better outcome to chemoradiation at 2 years.

Artificial Intelligence in Head and Neck Imaging.

Artificial intelligence (AI) can be applied to head and neck imaging to augment image quality and various clinical tasks including segmentation of tumor volumes, tumor characterization, tumor prognostication and treatment response, and prediction of metastatic lymph node disease. Head and neck oncology care is well positioned for the application of AI since treatment is guided by a wealth of information derived from CT, MRI, and PET imaging data. AI-based methods can integrate complex imaging, histologic, molecular, and clinical data to model tumor biology and behavior, and potentially identify associations, far beyond what conventional qualitative imaging can provide alone.

Role of MR Imaging in Head and Neck Squamous Cell Carcinoma.

Routine and advanced MR imaging sequences are used for locoregional spread, nodal, and distant staging of head and neck squamous cell carcinoma, aids treatment planning, predicts treatment response, differentiates recurrence for postradiation changes, and monitors patients after chemoradiotherapy.

Preimaging and Postimaging of Graft and Flap in Head and Neck Reconstruction.

Head and neck reconstructive surgical techniques are complex; now the microvascular free tissue transfer is the most frequently used. The postreconstruction imaging interpretation is challenging due to the altered anatomy and flap variability. We aim to improve radiologists' knowledge with diverse methods of flap reconstruction for an accurate appreciation of their expected cross-sectional imaging appearance and early detection of tumor recurrence and other complication.

MR Imaging of Vascular Malformations and Tumors of Head and Neck.

Soft tissue vascular anomalies show a wide heterogeneity of clinical manifestations and imaging features. MR imaging has an important role in the diagnosis and management of vascular lesions of the head and neck. MR angiography is mandatory in cases of arteriovenous and combined malformations to assess the high-flow nature/component of the lesions and plan therapy. Infantile hemangiomas can be differentiated from congenital hemangiomas by clinical course. Reactive vascular tumors have nonspecific features similar to infantile hemangiomas. Locally malignant and malignant vascular tumors have irregular borders, infiltration of different tissue planes, and lower apparent diffusion coefficient values than benign vascular tumors.

MR imaging of Oral Cavity and Oropharyngeal Cancer.

MR imaging is the modality of choice in the evaluation of oral cavity and oropharyngeal cancer. Routine postcontrast MR imaging is important for the accurate localization and characterization of the locoregional extension of oral cavity and oropharyngeal cancers. The anatomy of the oral cavity and oropharynx is complex; accurate interpretation is vital for description of the extension of the masses. Understanding the new changes in the eighth edition of the American Joint Committee on Cancer staging system. MR imaging is the imaging modality of choice for detection of perineural spread.

Delineation of Radiation Therapy Target Volumes for Lingual Nerve Involvement.

It is important for radiation oncologists to be able to accurately contour the lingual nerve pathway, as it is commonly involved in oral cavity cases. However, most atlases do not give a detailed account of the entire lingual nerve pathway as it traverses from the oral cavity, through the masticator space, to the base of the skull. Three experienced head and neck cancer specialists (two radiation oncologists and one neuroradiologist) examined anatomy textbooks, institutional magnetic resonance imaging (MRI), and computed tomography (CT) images of normal anatomy and also recurrences along the lingual nerve pathway to determine "anchor points" to help radiation oncologists contour more confidently. We found five anchor points to help radiation oncologists contour the lingual nerve pathway: At the level of the foramen ovale, the lateral pterygoid, the transition between lateral and medial pterygoid, the medial pterygoid (within the pterygomandibular space), and the oral cavity. Five anchor points with easily identifiable anatomy are established that radiation oncologists can use to contour the lingual nerve pathway more confidently.

Head and neck cancers on CT: preliminary study of treatment response assessment based on computerized volume analysis.

OBJECTIVE: The objective of our study was to investigate the feasibility of computerized segmentation of lesions on head and neck CT scans and evaluate its potential for estimating changes in tumor volume in response to treatment of head and neck cancers. MATERIALS AND METHODS: Twenty-six CT scans were retrospectively collected from the files of 13 patients with 35 head and neck lesions. The CT scans were obtained from an examination performed before treatment (pretreatment scan) and an examination performed after one cycle of chemotherapy (posttreatment scan). Thirteen lesions were primary site cancers and 22 were metastatic lymph nodes. An experienced radiologist (radiologist 1) marked the 35 lesions and outlined each lesion's 2D contour on the best slice on both the pre- and posttreatment scans. Full 3D contours were also manually extracted for the 13 primary tumors. Another experienced radiologist (radiologist 2) verified and modified, if necessary, all manually drawn 2D and 3D contours. An in-house-developed computerized system performed 3D segmentation based on a level set model. RESULTS: The computer-estimated change in tumor volume and percentage change in tumor volume between the pre- and posttreatment scans achieved a high correlation (intraclass correlation coefficient [ICC] = 0.98 and 0.98, respectively) with the estimates from manual segmentation for the 13 primary tumors. The average error in estimating the percentage change in tumor volume by automatic segmentation relative to the radiologists' average error was -1.5% +/- 5.4% (SD). For the 35 lesions, the ICC between the automatic and manual estimates of change in pre- to posttreatment tumor area was 0.93 and of percentage change in pre- to posttreatment tumor area was 0.85. The average error in estimating the percentage change in tumor area by automatic segmentation was -3.2% +/- 15.3%. CONCLUSION: Preliminary results indicate that this computerized segmentation system can reliably estimate changes in tumor size on CT scans relative to radiologists' manual segmentation. This information can be used to calculate changes in tumor size on pre- and posttreatment scans to assess response to treatment.

The utricular macula: qualitative and quantitative analysis using 3-T imaging.

PURPOSE: To identify and measure the mean size of the utricular macula using 3-T imaging. METHODS: One hundred one examinations using a 3-T magnetic resonance scanner and standard temporal bone protocol were performed over a 9-month period. Asymptomatic sides were then retrospectively evaluated using the axial T2-driven equilibrium sequence (0.3-mm slice thickness). We performed the following analyses: (1) reported frequency at which this structure could be identified and (2) calculated the mean size of the utricular macula. RESULTS: The utricular macula was identified in all 101 cases as an ellipsoid area of T2 hypointensity in the utricle. The average anteroposterior x transverse x craniocaudal dimensions were 1.7 x 1.5 x 1.0 mm. CONCLUSIONS: The utricular macula is consistently identified with 3-T imaging in asymptomatic patients.