Longitudinal Pattern of Lymphedema and Fibrosis in Patients With Oral Cavity or Oropharyngeal Cancer: A Prospective Study.

PURPOSE: The study aimed to describe the prevalence, severity, and trajectory of internal lymphedema, external lymphedema, and fibrosis in patients with oral cavity or oropharyngeal (OCOP) cancer. METHODS AND MATERIALS: One hundred twenty patients with newly diagnosed OCOP cancer were enrolled in a prospective longitudinal study. Recruitment was conducted at a comprehensive medical center. Participants were assessed pretreatment; at end of treatment; and at 3, 6, 9, and 12 months post-cancer treatment. Validated clinician-reported measures and computed tomography were used to assess the study outcomes. RESULTS: Seventy-six patients who completed the 9- or 12-month assessments were included in this report. Examination of the external lymphedema and fibrosis trajectories revealed that the total severity score peaked between the end of treatment and 3 months posttreatment and then decreased gradually over time but did not return to baseline by 12 months posttreatment (P < .001). The longitudinal patterns of severity scores for patients treated with surgery only or with multimodality therapy were similar. Examination of the internal swelling trajectories revealed that all patients experienced a significant increase in sites with swelling immediately posttreatment. For patients treated with surgery only, swelling was minimal and returned to baseline by 9 to 12 months posttreatment. Patients receiving multimodal treatment experienced a gradual decrease in number of sites with swelling during the 12-month posttreatment period that remained significantly above baseline (P < .05). Computed tomography revealed different patterns of changes in prevertebral soft tissue and epiglottic thickness in the surgery-only and multimodality treatment groups during the 12-month posttreatment period. There were minimal changes in thickness in both regions in the surgery-only group. Patients with multimodal treatment had significant increases in thickness in both regions 3 months posttreatment that remained thicker at 12 months than at baseline (P < .001). CONCLUSIONS: Lymphedema and fibrosis are the common complications of OCOP cancer therapy. Routine assessment, monitoring, and timely treatment of lymphedema and fibrosis are critical.

Epilepsy with anterior temporal encephaloceles: Baseline characteristics, post-surgical outcomes, and comparison to mesial temporal sclerosis.

OBJECTIVE: To review clinical and neuropsychological characteristics and natural history of a series of patients with temporal lobe epilepsy (TLE) and anterior temporal encephaloceles (ATE) and compare them to a similar series of TLE patients with mesial temporal sclerosis (MTS) to identify characteristics suggestive of ATE-related epilepsy. METHODS: Patients with epilepsy and ATE were identified via clinic encounters and consensus epilepsy surgery conference at a Level 4 epilepsy center. The drug-resistant subset of these patients who underwent epilepsy surgery (twenty-two of thirty-five) were compared to age- and laterality-matched patients with MTS. Clinical, neuropsychological, electrophysiologic, and surgical data were abstracted through chart review. RESULTS: In comparison with MTS, ATE patients were more often female, had significantly later onset of epilepsy, and did not have prior febrile seizures. In addition, ATE patients were more likely to have chronic headaches and other historical features consistent with idiopathic intracranial hypertension (IIH). Failure to identify ATE on initial imaging was common. Most patients had limited temporal cortical resections sparing mesial structures. Of the twenty ATE patients who had a long-term postsurgical follow-up, seventeen (85%) had International League Against Epilepsy (ILAE) Class 1 or 2 outcomes. SIGNIFICANCE: A shorter duration of epilepsy, female gender, and lack of history of febrile seizures may suggest ATE as an etiology of refractory TLE in adults. Targeted encephalocele resections can result in seizure freedom, underscoring the importance of encephalocele identification.

Association of Postoperative Sigmoid Sinus Occlusion and Cerebrospinal Fluid Leak in Translabyrinthine Surgery.

OBJECTIVE: To characterize the incidence of sigmoid sinus occlusion (SSO) following translabyrinthine (TL) surgery for posterior fossa tumor resection and determine the association with cerebrospinal fluid (CSF) leak. STUDY DESIGN: Retrospective case series. SETTING: Tertiary referral center. METHODS: Patients undergoing TL surgery for vestibular schwannoma from 2012 to 2020 were included. Demographic data, medical history, preoperative tumor length and volume, and postoperative complications including CSF leak were recorded. Neuroradiology review of postoperative magnetic resonance imaging was used to determine the presence or absence of flow through the sigmoid sinus. RESULTS: Of 205 patients undergoing TL, 21 (10.2%) experienced CSF leak postoperatively. Overall 56 (27%) demonstrated SSO on immediate postoperative magnetic resonance imaging. CSF leaks were more likely in those with SSO (19.6%) than those without SSO (6.7%; odds ratio, 3.54 [95% CI, 1.25-10.17]). Tumor volume and body mass index were not significantly associated with CSF leak. In total, 105 (51%) patients had some degree of sigmoid sinus thrombosis, but nonocclusive thrombosis was not associated with CSF leak. CONCLUSION: SSO after TL approaches is common and appears to be significantly associated with postoperative CSF leak development. Minimizing manipulation of the sigmoid sinus during TL surgery and compression after surgery may have a role in preventing CSF leak.

Diameter-Based Volumetric Models May Inadequately Calculate Jugular Paraganglioma Volume Following Sub-Total Resection.

BACKGROUND: As gross total resection of jugular paragangliomas (JPs) may result in cranial nerve deficits, JPs are increasingly managed with subtotal resection (STR) with postoperative radiological monitoring. However, the validity of commonly used diameter-based models that calculate postoperative volume to determine residual tumor growth is dubious. The purpose of this study was to assess the accuracy of these models compared to manual volumetric slice-by-slice segmentation. METHODS: A senior neuroradiologist measured volumes via slice-by-slice segmentation of JPs pre- and postoperatively from patients who underwent STR from 2007 to 2019. Volumes from three linear-based models were calculated. Models with absolute percent error (APE) > 20% were considered unsatisfactory based on a common volumetric definition for residual growth. Bland-Altman plots were used to evaluate reproducibility, and Wilcoxon matched-pairs signed rank test evaluated model bias. RESULTS: Twenty-one patients were included. Median postoperative APE exceeded the established 20% threshold for each of the volumetric models as cuboidal, ellipsoidal, and spherical model APE were 63%, 28%, and 27%, respectively. The postoperative cuboidal model had significant systematic bias overestimating volume (p = 0.002) whereas the postoperative ellipsoidal and spherical models lacked systematic bias (p = 0.11 and p = 0.82). CONCLUSION: Cuboidal, ellipsoidal, and spherical models do not provide accurate assessments of postoperative JP tumor volume and may result in salvage therapies that are unnecessary or inappropriately withheld due to inaccurate assessment of residual tumor growth. While more time-consuming, slice-by-slice segmentation by an experienced neuroradiologist provides a substantially more accurate and precise measurement of tumor volume that may optimize clinical management.

Contemporary Management of Jugular Paragangliomas With Neural Preservation.

OBJECTIVES: Management of jugular paragangliomas (PGL) has evolved toward subtotal resection (STR). The purpose of this study is to analyze neural preservation and adjuvant treatment for long-term local control. STUDY DESIGN: Retrospective chart review. SETTINGS: Tertiary neurotology practice. SUBJECTS AND METHODS: Adults undergoing surgical treatment of jugular PGL between 2006 and 2019. Patients, disease, and treatment variables were collected retrospectively. Single predictor logistic regression was used to ascertain predictors of regrowth or need for salvage radiation. RESULTS: A total of 41 patients (median age, 47 years; 76% female) were identified. Most patients presented with advanced-stage disease (Glasscock-Jackson stage III-IV = 76%). Subtotal resection (STR) was performed in 32 (78%) patients. Extended STR (type 1) was the most commonly performed conservative procedure (n = 19, 59%). Postoperative new low cranial neuropathy (LCN) involving CN X and XII was rare (n = 3 and n = 1, respectively). Seventeen patients (41%) underwent postsurgical therapy for tumor regrowth or recurrence, including 15 patients who underwent adjuvant (n = 4) or salvage (n = 11) radiation. Overall tumor control of 94.7% was achieved at a mean follow-up of 35 months. All patients treated with combined modality treatment had local control at last follow-up. Logistic regression identified no single predictor for postsurgical radiation treatment or salvage-free survival. CONCLUSION: Management of jugular PGL with a conservative approach is safe and effective with a low rate of new LCN deficit. Active surveillance of residual tumor with salvage radiation for growth results in excellent long-term tumor control.

Chronic Electroconvulsive Therapy May Induce Calvarial Hyperemia and Marrow Replacement.

ABSTRACT: Electroconvulsive therapy (ECT) is a treatment option for a number of psychiatric disorders, including refractory major depression and obsessive compulsive disorder. There are no known structural sequelae of ECT. Here we present a patient with severe refractory obsessive compulsive disorder and major depression treated over 2 years with ECT every 2 weeks. Planning magnetic resonance imaging intended for a potential procedural intervention for her psychiatric disease incidentally demonstrated a new area of increased enhancement and loss of marrow signal within the right frontal bone. Imaging findings were suggestive of underlying bone marrow or bone changes, although there was no evidence of bone destruction on bone-windowed computed tomography (CT) and there was no uptake on nuclear bone scan. The CT chest/abdomen/pelvis were also reassuring that this did not represent metastatic disease, and findings were unchanged on repeat magnetic resonance imaging 4 months later. Thus, this area corresponded to the site directly underlying the unilateral ECT electrode placement, suggestive of never-before described ECT-induced hyperemia. We report for the first time that frequent, chronic ECT may induce asymptomatic skull bone marrow hyperemia with radiologic findings. This appears to be a direct consequence of electrical current leading to chronic inflammatory and edematous marrow replacement. Electroconvulsive therapy should be added to the neuroradiological differential diagnosis of calvarial enhancement and loss of marrow signal. Psychiatrists should counsel patients on the possibility of this rare radiological finding, which may be confused for other processes.

Baseline neuropsychological characteristics in patients with epilepsy with left temporal lobe encephaloceles compared with left mesial temporal sclerosis.

BACKGROUND: Temporal lobe encephaloceles (TE) are increasingly recognized as a cause of drug-resistant temporal lobe epilepsy. Improved recognition of these lesions offers an opportunity to treat them with a limited resection sparing the hippocampus. However, as they can be difficult to identify on imaging, additional clues pointing to the diagnosis can be helpful. We sought to understand the baseline cognitive/neuropsychological profile in patients with left temporal lobe epilepsy caused by encephaloceles compared with that caused by mesial temporal sclerosis (MTS), a common entity in the differential diagnosis. METHODS: Neuropsychological testing, including language (semantic and phonemic fluency and naming), verbal memory, intelligence quotient (IQ), and executive function measures were compared across two groups (five patients with left TE and five age- and gender-matched patients with left MTS). Other clinical variables related to cognition, including patient age, electroencephalographic characteristics, epilepsy duration, and factors related to antiseizure medication dosing, were also compared between groups. RESULTS: More patients with left MTS had atypical language lateralization (3/5 with right-sided language in the group with MTS compared with 0/5 in the group with TE). Patients with MTS had significantly worse scores on the Verbal Comprehension Index (VCI) subscore of the Wechsler Adult Intelligence Scale (WAIS; p = 0.026). General IQ was also worse in patients with MTS (p = 0.028). There was a trend towards worse executive function in patients with MTS as measured on Trails B (p = 0.096). Other measures related to language and verbal memory did not differ significantly between the groups nor did other relevant clinical variables, except epilepsy duration, which was significantly longer in patients with MTS (p = 0.0001). CONCLUSIONS: This pilot study demonstrates few significant differences between the groups with left MTS and TE surveyed. A higher rate of atypical language lateralization was noted in patients with left MTS. The higher baseline global IQ and VCI scores in patients with left TE compared with patients with MTS may be attributable to longer duration of epilepsy in patients with left MTS. Future work with a larger sample size will focus on establishing a unique neuropsychological profile related to epilepsy due to TE.

Transcervical sonography and human papillomavirus 16 E6 antibodies are sensitive for the detection of oropharyngeal cancer.

BACKGROUND: Human papillomavirus 16 (HPV-16) E6 seropositivity is a promising early marker of human papillomavirus-driven oropharyngeal cancer (HPV-OPC), yet more sensitive imaging modalities are needed before screening is considered. The objective of this study was to determine the sensitivity of transcervical sonography (TCS) for detecting clinically apparent HPV-OPC in comparison with computed tomography (CT) and positron emission tomography (PET)/CT. METHODS: Fifty-one patients with known or suspected HPV-OPC without prior treatment underwent oropharyngeal TCS and blood collection (for HPV multiplex serology testing). Eight standard sonographic images were collected; primary-site tumors were measured in 3 dimensions if identified. Each patient underwent a full diagnostic workup as part of standard clinical care. The pathologic details, HPV status, final staging, and imaging findings were abstracted from the medical record. The sensitivity of each imaging modality was compared with the final clinical diagnosis (the gold standard). RESULTS: Twenty-four base of tongue cancers (47%), 22 tonsillar cancers (43%), and 2 unknown primary cancers (4%) were diagnosed; 3 patients (6%) had no tumors. All p16-tested patients were positive (n = 47). Primary-site tumors were correctly identified in 90.2% (95% confidence interval [CI], 78.6%-96.7%) with TCS, in 69.4% (95% CI, 54.6%-81.7%) with CT, and in 83.3% (95% CI, 68.6%-93.0%) with PET/CT. TCS identified tumors in 10 of 14 cases missed by CT and recognized the absence of tumors in 3 cases for which CT or PET/CT was falsely positive. The smallest sonographically identified primary-site tumor was 0.5 cm in its greatest dimension; the average size was 2.3 cm. Among p16-positive patients, 76.1% (95% CI, 61.2%-87.4%) were seropositive for HPV-16 E6. CONCLUSIONS: TCS and HPV-16 E6 antibodies are sensitive for the diagnosis of HPV-OPC.

ACR Appropriateness Criteria® Neck Mass-Adenopathy.

A palpable neck mass may be the result of neoplastic, congenital, or inflammatory disease. Older age suggests neoplasia, and a congenital etiology is more prevalent in the pediatric population. The imaging approach is based on the patient age, mass location, and clinical pulsatility. Underlying human papillomavirus-related malignancy should be considered in all age groups. Although the imaging appearance of some processes in the head and neck overlap, choosing the appropriate imaging examination may allow a specific diagnosis, or a limited differential diagnosis. Tissue sampling is indicated to confirm suspected malignancy. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Suspected Spine Trauma.

Injuries to the cervical and thoracolumbar spine are commonly encountered in trauma patients presenting for treatment. Cervical spine injuries occur in 3% to 4% and thoracolumbar fractures in 4% to 7% of blunt trauma patients presenting to the emergency department. Clear, validated criteria exist for screening the cervical spine in blunt trauma. Screening criteria for cervical vascular injury and thoracolumbar spine injury have less validation and widespread acceptance compared with cervical spine screening. No validated criteria exist for screening of neurologic injuries in the setting of spine trauma. CT is preferred to radiographs for initial assessment of spine trauma. CT angiography and MR angiography are both acceptable in assessment for cervical vascular injury. MRI is preferred to CT myelography for assessing neurologic injury in the setting of spine trauma. MRI is usually appropriate when there is concern for ligament injury or in screening obtunded patients for cervical spine instability. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Acute Mental Status Change, Delirium, and New Onset Psychosis.

Acute changes in mental status represent a broad collection of symptoms used to describe disorders in mentation and level of arousal, including the more narrowly defined diagnoses of delirium and psychosis. A wide range of precipitating factors may be responsible for symptom onset including infection, intoxication, and metabolic disorders. Neurologic causes that may be detected on neuroimaging include stroke, traumatic brain injury, nonconvulsive seizure, central nervous system infection, tumors, hydrocephalus, and inflammatory disorders. Not infrequently, two or more precipitating factors may be found. Neuroimaging with CT or MRI is usually appropriate if the clinical suspicion for an acute neurological cause is high, where the cause of symptoms is not found on initial assessment, and for patients whose symptoms do not respond appropriately to management. There was disagreement regarding the appropriateness of neuroimaging in cases where a suspected, nonneurologic cause is found on initial assessment. Neuroimaging with CT is usually appropriate for patients presenting with delirium, although the yield may be low in the absence of trauma or a focal neurological deficit. Neuroimaging with CT or MRI may be appropriate in the evaluation of new onset psychosis, although the yield may be low in the absence of a neurologic deficit. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Cervical Neck Pain or Cervical Radiculopathy.

Nontraumatic neck pain is a leading cause of disability, with nearly 50% of individuals experiencing ongoing or recurrent symptoms. Radiographs are appropriate as initial imaging for cervical or neck pain in the absence of "red flag" symptoms or if there are unchanging chronic symptoms; however, spondylotic changes are commonly identified and may result in both false-positive and false-negative findings. Noncontrast CT can be complementary to radiographs for evaluation of new or changing symptoms in the setting of prior cervical spine surgery or in the assessment of extent of ossification in the posterior longitudinal ligament. Noncontrast MRI is usually appropriate for assessment of new or increasing radiculopathy due to improved nerve root definition. MRI without and with contrast is usually appropriate in patients with new or increasing cervical or neck pain or radiculopathy in the setting of suspected infection or known malignancy. Imaging may be appropriate; however, it is not always indicated for evaluation of cervicogenic headache without neurologic deficit. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Secretory Carcinoma of the Thyroid Gland: Report of a Highly Aggressive Case Clinically Mimicking Undifferentiated Carcinoma and Review of the Literature.

After being described in the salivary glands as a malignancy with features essentially identical to those of the breast, secretory carcinoma (SC) (formerly mammary analogue SC) has now been identified in other sites including the skin, lung, and thyroid gland. In the breast, SC has a relatively favorable prognosis. Likewise when arising in the salivary glands, it is generally considered to be a low to intermediate grade carcinoma; however, there is a range of clinical behavior with occasional patients dying of progressive disease. SCs of the thyroid gland are rare, and reports suggest a relatively aggressive behavior, at least relative to well differentiated carcinomas such as papillary carcinoma and minimally invasive follicular carcinoma. We present a patient with a highly aggressive thyroid gland SC that mimicked undifferentiated carcinoma clinically. The patient had widespread metastatic disease and died rapidly from airway compromise. We also review the literature for reported cases of thyroid gland SC in order to better establish the clinical features and expected clinical course of such tumors occurring at this site.

ACR Appropriateness Criteria® Hearing Loss and/or Vertigo.

This article presents guidelines for imaging utilization in patients presenting with hearing loss or vertigo, symptoms that sometimes occur concurrently due to proximity of receptors and neural pathways responsible for hearing and balance. These guidelines take into account the superiority of CT in providing bony details and better soft-tissue resolution offered by MRI. It should be noted that a dedicated temporal bone CT rather than a head CT best achieves delineation of disease in many of these patients. Similarly, optimal assessment often requires a dedicated high-resolution protocol designed to assess temporal bone and internal auditory canals even though such a study will be requested and billed as a brain MRI. Angiographic techniques are helpful in some patients, especially in the setting of vertigo. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Evaluation of CT Changes in the Head and Neck After Cancer Treatment: Development of a Measurement Tool.

BACKGROUND: The late effect continuum of lymphedema and fibrosis (LEF) affects more than 70% of patients after treatment for head and neck cancer (HNC). LEF is associated with symptom burden and decreased function and quality of life. Although surveillance imaging is common posttreatment, objective assessment of soft tissues is not, likely due to the lack of objective evaluation methods and understanding of the significance of LEF. We undertook the development of a tool to measure LEF using CT scans in HNC patients. METHODS AND RESULTS: We developed a CT measurement tool assessing sites of soft tissue damage secondary to tumor, surgery, or radiation. The tool was applied to pre- and posttreatment CT scans for 10 HNC patients. The data were reviewed, and the initial tool was modified. Ten additional patients' scans were assessed using the revised tool. The tool was modified further after data review by an expert panel and was then applied to scans from all 20 patients. The final tool included 11 items as follows: grading of fat stranding at 6 sites (axial reconstruction images, scale 0-2), measurement of epiglottic thickness (sagittal images, scale mm), and measurement of prevertebral soft tissue thickness at C3 (sagittal images, scale mm). A total of 176 CT scans were evaluated from 20 patients (range 4-14 examinations/patient). Preliminary data demonstrated face validity. CONCLUSIONS: The final LEF assessment tool (CT-LEFAT) provides a standardized method for assessing critical sites that are involved by LEF. Studies to assess reliability and validity are ongoing.

Misdiagnosis: CNS Erdheim-Chester disease mimicking CLIPPERS.

Introduction Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory central nervous system (CNS) disorder with particular involvement of the pons. Diagnostic criteria include a range of clinical symptoms related to the underlying brainstem pathology, visible with magnetic resonance imaging (MRI). MRI findings include the appearance of punctuate and curvilinear gadolinium enhancement 'peppering' the pons. We discuss a patient presenting with clinical and radiographic characteristics of CLIPPERS who was diagnosed with Erdheim-Chester disease (ECD). Case report A 52-year-old male presented with 2 years of progressive spasticity, dysarthria, and gait instability. Initially, he was diagnosed with Parkinson's disease at an outside hospital, based on tremor, rigidity, and gait instability; however, he failed to improve with a trial of levodopa. Brain MRI showed small enhancing parenchymal nodules coalescing in the central pons, but also affecting the cerebellum and cerebellar peduncles, with more punctate enhancing lesions in the cerebral lobar subcortical white matter. When the patient's response to steroids was inadequate, further imaging was done, revealing perinephric processes. Subsequent biopsy revealed ECD. Conclusions A review of the literature for cases of CLIPPERS demonstrated a subset of patients later found to have various malignancies involving the CNS. This case report uses the patient's unique radiographic and clinical presentation to demonstrate the importance of the exclusion criteria within the CLIPPERS diagnostic requirements and stresses red flags suggestive of alternative diagnoses. This distinction is of high importance when differentiating a relatively benign process such as CLIPPERS from more malignant diseases.

ACR Appropriateness Criteria® Sinonasal Disease.

Imaging of sinonasal pathology may occur for assessment of rhinosinusitis or mass lesions. Rhinosinusitis is prevalent in up to 16% of the US population with annual economic burdens estimated at 22 billion dollars. Rhinosinusitis is characterized as acute or chronic based on symptom duration; if four or more episodes occur annually, the term recurrent acute rhinosinusitis (RARS) is used. In acute uncomplicated rhinosinusitis when inflammatory change remains in the paranasal sinuses and nasal cavity, imaging may not be required. Distinction between viral or bacterial rhinosinusitis is a clinical diagnosis, and imaging should be interpreted in conjunction with clinical and endoscopic findings. Sinus CT imaging is appropriate per clinical judgment in associated complications including headache, facial pain, swelling, orbital proptosis, or cranial nerve palsies. In maxillary sinusitis, teeth may require assessment because 20% may be odontogenic in origin. MRI may be complementary in aggressive infections with intraocular/intracranial complications, invasive fungal sinusitis, or sinonasal masses. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Tinnitus.

Tinnitus is the perception of sound in the absence of an external source. It is a common symptom that can be related to hearing loss and other benign causes. However, tinnitus may be disabling and can be the only symptom in a patient with a central nervous system process disorder. History and physical examination are crucial first steps to determine the need for imaging. CT and MRI are useful in the setting of pulsatile tinnitus to evaluate for an underlying vascular anomaly or abnormality. If there is concomitant asymmetric hearing loss, neurologic deficit, or head trauma, imaging should be guided by those respective ACR Appropriateness Criteria® documents, rather than the presence of tinnitus. Imaging is not usually appropriate in the evaluation of subjective, nonpulsatile tinnitus that does not localize to one ear. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.