RadioGraphics Update: Parathyroid CT and Primary Hyperparathyroidism.

Editor's Note.-RadioGraphics Update articles supplement or update information found in full-length articles previously published in RadioGraphics. These updates, written by at least one author of the previous article, provide a brief synopsis that emphasizes important new information such as technological advances, revised imaging protocols, new clinical guidelines involving imaging, or updated classification schemes.

Sinonasal organized hematoma: Case report and review of the literature.

Sinonasal organized hematoma is a rare condition characterized by an organizing blood clot in the sinonasal cavity, which consists of blood products, fibrin, and dilated blood vessels. As a benign entity with an aggressive imaging appearance, it is important to differentiate sinonasal organized hematoma from malignancies affecting the paranasal sinuses and nasal cavities to guide appropriate management. In this report, we discuss the clinical presentation and diagnostic evaluation of an 82-year-old male with a left maxillary sinus organized hematoma and provide a comprehensive review of the relevant literature.

Parathyroid 4D CT in Primary Hyperparathyroidism: Exploration of Size Measurements for Identifying Multigland Disease and Guiding Biochemically Successful Parathyroidectomy.

BACKGROUND. In patients with primary hyperparathyroidism (PHPT), bilateral neck exploration is necessary for multigland disease (MGD), whereas minimally invasive parathyroidectomy is often preferred for single-gland disease (SGD). An existing system (the 4D-CT MGD score) for differentiating SGD from MGD with the use of preoperative parathyroid CT considers the size of only the largest candidate lesion. OBJECTIVE. The purpose of this study was to assess the utility of the size of the second-largest lesion on parathyroid CT for differentiating SGD from MGD as well as the utility of individual gland size for predicting the need for surgical removal and to derive optimal size thresholds for these purposes. METHODS. This retrospective study included patients with PHPT who underwent biochemically successful parathyroidectomy after preoperative parathyroid CT. Clinical radiology reports were reviewed to classify reported candidate parathyroid lesions as low-, intermediate-, or high-confidence lesions. Resected hypercellular parathyroid lesions were correlated with clinically reported candidate lesions. Patients were classified as having SGD or MGD on the basis of operative and pathology reports, independent of CT findings. One observer retrospectively determined the estimated volume (0.52 × length × width × height) and maximum diameter of clinically reported high-confidence lesions, as well as the 4D-CT MGD scores from the examinations. Diagnostic performance was assessed. RESULTS. The sample comprised 62 patients (41 women, 21 men; median age, 65 years), 47 of whom had SGD and 15 of whom had MGD, with 151 candidate lesions, including 106 high-confidence lesions. Based on the second-largest high-confidence lesions, an estimated volume threshold of 60 mm3 or greater achieved 53% sensitivity and 96% specificity, whereas a maximum diameter threshold of 7 mm or greater achieved 67% sensitivity and 96% specificity for MGD; a 4D-CT MGD score of 3 or greater achieved 47% sensitivity and 68% specificity for MGD. For predicting the need to remove a gland for successful parathyroidectomy, an estimated volume threshold of 114 mm3 or greater achieved 84% sensitivity and 97% specificity, and a threshold of 55 mm3 or greater achieved 93% sensitivity and 87% specificity; a maximum diameter threshold of 7 mm or greater achieved 93% sensitivity and 84% specificity. CONCLUSION. The estimated volume and maximum diameter of high-confidence candidate lesions can differentiate SGD from MGD and identify individual glands requiring removal for successful parathyroidectomy. Differentiating SGD from MGD may be aided by considering both the first- and second-largest high-confidence lesions. CLINICAL IMPACT. The findings will help identify patients who are likely to require bilateral neck explorations, informing preoperative patient counseling and individualized operative planning.

Optic Nerve Sheath Diameter Measured by Point-of-Care Ultrasound and MRI.

BACKGROUND AND PURPOSE: Ultrasound (US) measurement of the optic nerve sheath diameter (ONSD) and optic nerve diameter (OND) is a method frequently used to screen for an increased intracranial pressure. The aim of this study was to assess the accuracy of US measurements of ONSD and OND, when compared to magnetic resonance imaging (MRI) measurements as the criterion standard. METHODS: In this prospective, single-institution study, orbital US was performed for those patients requiring an emergent brain MRI. ONSD and OND of both eyes were measured in the axial and coronal planes in straight gaze by US. ONSD and OND from brain and orbital MRI were measured by two neuroradiologists. Correlation and agreement between readings were assessed using Pearson's correlations. RESULTS: Eighty-two patients met inclusion criteria. The mean axial and coronal ONSD in the MRI examinations was 5.6 and 5.7 mm at 3-5.9 mm behind the globe, respectively. The mean ONSD from the US measurements was 6.22 and 5.52 mm in the axial and coronal planes, respectively. The mean OND in US examinations was 4.31 mm (axial) and 3.68 mm (coronal). Axial versus coronal measurements of ONSD had a modest correlation in US assessment with an r2 of .385 (P < .001) but there were no correlations between any of the US and MRI measurements. CONCLUSIONS: In measuring ONSD and OND, US measurements showed a modest correlation between axial and coronal measurements, but no concordance was found between US and MRI in our setting.

The T2-FLAIR-mismatch sign as an imaging biomarker for IDH and 1p/19q status in diffuse low-grade gliomas: a systematic review with a Bayesian approach to evaluation of diagnostic test performance.

OBJECTIVE: With the revised WHO 2016 classification of brain tumors, there has been increasing interest in imaging biomarkers to predict molecular status and improve the yield of genetic testing for diffuse low-grade gliomas (LGGs). The T2-FLAIR-mismatch sign has been suggested to be a highly specific radiographic marker of isocitrate dehydrogenase (IDH) gene mutation and 1p/19q codeletion status in diffuse LGGs. The presence of T2-FLAIR mismatch indicates a T2-hyperintense lesion that is hypointense on FLAIR with the exception of a hyperintense rim. METHODS: In accordance with PRISMA guidelines, we performed a systematic review of the Ovid Medline, Embase, Scopus, and Cochrane databases for reports of studies evaluating the diagnostic performance of T2-FLAIR mismatch in predicting the IDH and 1p/19q codeletion status in diffuse LGGs. Results were combined into a 2 × 2 format, and the following diagnostic performance parameters were calculated: sensitivity, specificity, positive predictive value, negative predictive value, and positive (LR+) and negative (LR-) likelihood ratios. In addition, we utilized Bayes theorem to calculate posttest probabilities as a function of known pretest probabilities from previous genome-wide association studies and the calculated LRs. Calculations were performed for 1) IDH mutation with 1p/19q codeletion (IDHmut-Codel), 2) IDH mutation without 1p/19q codeletion (IDHmut-Noncodel), 3) IDH mutation overall, and 4) 1p/19q codeletion overall. The QUADAS-2 (revised Quality Assessment of Diagnostic Accuracy Studies) tool was utilized for critical appraisal of included studies. RESULTS: A total of 4 studies were included, with inclusion of 2 separate cohorts from a study reporting testing and validation (n = 746). From pooled analysis of all cohorts, the following values were obtained for each molecular profile-IDHmut-Codel: sensitivity 30%, specificity 73%, LR+ 1.1, LR- 1.0; IDHmut-Noncodel: sensitivity 33.7%, specificity 98.5%, LR+ 22.5, LR- 0.7; IDH: sensitivity 32%, specificity 100%, LR+ 32.1, LR- 0.7; 1p/19q codeletion: sensitivity 0%, specificity 54%, LR+ 0.01, LR- 1.9. Bayes theorem was used to calculate the following posttest probabilities after a positive and negative result, respectively-IDHmut-Codel: 32.2% and 29.4%; IDHmut-Noncodel: 95% and 40%; IDH: 99.2% and 73.5%; 1p/19q codeletion: 0.4% and 35.1%. CONCLUSIONS: The T2-FLAIR-mismatch sign is an insensitive but highly specific marker of IDH mutation but not 1p/19q codeletion in diffuse LGGs, although there may be significant exceptions. These findings support the utility of T2-FLAIR mismatch as an imaging-based biomarker for positive selection of patients with IDH-mutant gliomas.

Emphysematous osteomyelitis: Report of two cases and review of literature.

Emphysematous osteomyelitis is a rare condition characterized by the presence of intraosseous gas. A prompt diagnosis is required for this disease to expedite management as it is a potentially fatal condition. Many comorbidities, such as malignancy, diabetes mellitus, alcohol abuse, Crohn's disease, and other etiologies causing immunosuppression, predispose to this condition. The causative organisms are generally anaerobes or members of Enterobacteriaceae family; however, the infection can be mono or polymicrobial. We report two cases affected with emphysematous osteomyelitis due to varied underlying comorbidities. The purpose of this study is to (a) emphasize the importance of computed tomography in diagnosing emphysematous osteomyelitis and (b) to highlight an unusual location of this rare pathology.

A Low-Cost, Low-Skill Model for Efficient Breast Cancer Screening in Low Resource Rural Settings of a Developing Country.

Objective To suggest a low-cost, easily-operable, non-invasive imaging modality for cancer detection in rural settings. Method A total of 212 cases with palpable breast masses aged 18 - 65 years were enrolled and underwent thorough clinical, mammographic, and ultrasonographic (USG) evaluation. Imaging findings were reported using the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS®) criteria. The findings were confirmed histopathologically. Data were analyzed using the Chi-square test. Results The malignancy rate was 35.8% (n = 76). On mammography, lesions size, margins, shape, calcification, and distorted arch/skin thickening were significantly associated with malignancy. On USG, the number of nodules, shape, margins, echotexture, posterior wall echo, through transmission changes, distorted arch/skin thickening, microlobulation, duct extension, and height/width ratio were significantly associated with malignancy. Independently, mammography and USG had a sensitivity of 78.1% and 80.3%, respectively, and a specificity of 83.3% and 89.0%, respectively. Using a positive result of either study as the criteria, the sensitivity was 97.4% and the specificity was 80.1%. Conclusion The combined use of mammography and USG provides high sensitivity and specificity, thus showing that a combination of two can be used as a screening tool for use in low resource rural settings.

The Utility of Dual Energy Computed Tomography in Musculoskeletal Imaging.

The objective of this article is to review the mechanisms, advantages and disadvantages of dual energy computed tomography (DECT) over conventional tomography (CT) in musculoskeletal imaging as DECT provides additional information about tissue composition and artifact reduction. This provides clinical utility in detection of urate crystals, bone marrow edema, reduction of beam hardening metallic artifact, and ligament and tendon analysis.

Unique Association of Multiple Seminal Vesicle Cysts with Contralateral Renal Agenesis: A Rare Variant of Zinner Syndrome.

Zinner syndrome is a rare developmental anomaly of the Wolffian (mesonephric) duct which is characterised by a triad of obstruction of the ejaculatory duct, the ipsilateral seminal vesicle cyst, and the ipsilateral renal agenesis. The aim of this case report is to emphasize the importance of radiological imaging in diagnosing the condition and to report its rare unusual variant.

Evaluation of Prostatic Lesions by Transrectal Ultrasound, Color Doppler, and the Histopathological Correlation.

Objective To evaluate the role of a transrectal ultrasound (TRUS) guided biopsy and a color Doppler test in the detection of prostate cancer in patients with increased serum prostate-specific antigen (PSA) levels and/or an abnormal digital rectal examination (DRE). Method A total of 40 cases, ranging in age from 50 to 80 years and showing increased serum PSA levels (4-10 ng/ml) and/or abnormal DRE, were enrolled and underwent TRUS evaluation followed by color Doppler flowmetric studies. A TRUS-guided biopsy was performed in all the cases. The findings were confirmed histopathologically. Data were analyzed using the chi-square test. Results Histopathologically, a total of 13 cases (32.5%) were malignant. On TRUS, irregular shape, heterogeneous echotexture loss of differentiation between the peripheral and internal zones, less mean weight of the prostate, and capsular invasion were significantly associated with malignancy. On flowmetry, moderate vascularity and focal asymmetry were significantly associated with malignancy. The combined use of TRUS and color Doppler flowmetry was found to be 100% sensitive and 92.6% specific and had a positive predictive value (PPV) and a negative predictive value (NPV) of 86.7% and 100%, respectively. Conclusion TRUS with color Doppler flowmetry was highly sensitive and specific in the detection of prostate malignancy.

Disparate Presentations of Localized Cystic Disease of Kidney: A Review with an Objective of Correct Approach for Accurate Treatment Plan.

BACKGROUND: Localized cystic disease of the kidney is a rare, non-familial condition. Its imaging and clinical features are unique and need to be differentiated from autosomal dominant polycystic kidney disease and focal cystic masses such as multicystic nephroma and cystic renal cell carcinoma. It is always restricted to one kidney and is characterized by multiple cysts of varying sizes separated by residual normal renal tissue. MATERIALS AND METHODS: This study reports 12 cases of localized cystic disease of the kidney based on imaging findings and clinical histories. The modalities of choice were ultrasonography followed by contrast-enhanced computed tomography. Eight out of 12 patients were men and the average age of presentation was 46 years. The screening of family members and relatives was done to rule out the differentials. RESULTS: Localized cystic disease of kidney was diagnosed in all the patients and it presented in two different forms. In three patients, multiple cysts involved whole of the kidney, resulting in thinned-out residual renal parenchyma. In the rest nine patients it remained localised to a particular segment of the kidney. No cysts were observed in the contralateral kidney in seven patients, and one or two simple cysts were observed in five. Clinical presentations included only flank pain in six patients, flank pain with palpable abdominal mass in four patients, two patients presented as asymptomatic cases with diagnosis as an incidental finding and one patient with hematuria. Eight patients underwent imaging and two underwent clinical follow-up for a period of two years showing stability of the disease. One patient underwent nephrectomy for suspected renal neoplasm. CONCLUSION: Localized cystic disease of the kidney is a unilateral, rare and stable disease that has two different forms of presentations. Its imaging findings should be clearly understood so as to not classify it as a separate disease and avoid unnecessary surgery. It rarely leads to hypertension or polycythemia, and until then no definitive management is required. It can be followed up using imaging techniques and requires nephrectomy only when the suspicion of malignancy is strong.

Caffey's Disease Sans Mandibular and Clavicular Involvement: A Rare Case Report.

Caffey's disease, also known as Infantile Cortical Hyperostosis, is a rare, self-limited, benign, inflammatory gene-related disorder of infants that causes bone changes, soft tissue swelling, and irritability. The mandible (75%), clavicles, and ulnae are the bones most frequently involved, others being long bones, lateral ribs, ilia with skull being the rarest. However, we report a case of a 5-month-old male diagnosed with Infantile cortical hyperostosis but with absent mandibular and clavicular involvement, thus depicting the unusual presentation of this disease.

Role of Color Doppler Flowmetry in Prediction of Intrauterine Growth Retardation in High-Risk Pregnancy.

OBJECTIVE: To evaluate the usefulness of Color Doppler flowmetry in the prediction of intrauterine growth restriction (IUGR) in high-risk pregnancies. MATERIALS AND METHOD: A total of 62 high-risk pregnant women underwent Color Doppler flowmetric umbilical artery pulsatility index (PI), resistive index (RI) and systolic/diastolic (S/D) ratio, middle cerebral artery PI, RI and S/D ratio, Ductus venosus S-wave/isovolumetric A-wave index (SIA) and vertebral artery RI at 23-27 weeks, 28-32 weeks and 32-36 weeks of their pregnancy. Cerebral-umbilical C/U PI, RI and S/D were evaluated at the third visit. All the pregnancies were followed up till delivery. Ponderal index <10 was considered to be indicative of IUGR. Data were analyzed using IBM Statistical Package for Social Sciences (SPSS) 21.0. RESULTS: Thirty-nine (62.9%) deliveries were IUGR. On all the three visits, umbilical artery, mean PI, RI and SD values were significantly higher while MCA PI, RI and SD values were significantly lower in IUGR as compared to non-IUGR cases. Third visit C/U PI, RI and SD ratio values were also significantly lower in IUGR as compared to non-IUGR cases. Ductus venosus SIA values did not show a significant difference between IUGR and non-IUGR groups. The vertebral artery resistive index was significantly higher in non-IUGR as compared to IUGR on all the visits. Umbilical artery PI was the most sensitive and specific for the prediction of IUGR at all the three visits, with the maximum sensitivity and specificity at the third visit (82.1% and 87%). Third visit C/U PI was most sensitive (82.1%) and specific (96.7%) for the prediction of IUGR. CONCLUSION: This showed that Doppler flowmetry is a useful method for the prediction of IUGR in high-risk pregnancies.

The Impact of Surgery and Stored Red Blood Cell Transfusions on Nitric Oxide Homeostasis.

BACKGROUND: Cell-free hemoglobin (Hb) forms in stored red blood cells (RBCs) as a result of hemolysis. Studies suggest that this cell-free Hb may decrease nitric oxide (NO) bioavailability, potentially leading to endothelial dysfunction, vascular injury, and multiorgan dysfunction after transfusion. We tested the hypothesis that moderate doses of stored RBC transfusions increase cell-free Hb and decrease NO availability in postoperative surgical patients. METHODS: Twenty-six patients undergoing multilevel spine fusion surgery were studied. We compared those who received no stored RBCs (n = 9) with those who received moderate amounts (6.1 ± 3.0 units) of stored RBCs over 3 perioperative days (n = 17). Percent hemolysis (cell-free Hb), RBC-NO (heme-NO), and plasma nitrite and nitrate were measured in samples from the stored RBC bags and from patients' blood, before and after surgery. RESULTS: Posttransfusion hemolysis was increased approximately 3.5-fold over preoperative levels (P = 0.0002) in blood samples collected immediately after surgery but not on postoperative days 1 to 3. Decreases in both heme-NO (by approximately 50%) and plasma nitrite (by approximately 40%) occurred postoperatively, both in nontransfused patients (P = 0.036 and P = 0.026, respectively) and transfused patients (P = 0.0068 and P = 0.003, respectively) and returned to preoperative baseline levels by postoperative day 2 or 3. Postoperative plasma nitrite and nitrate were decreased significantly in both groups, and this change was slower to return to baseline in the transfused patients, suggesting that blood loss and hemodilution from crystalloid administration contribute to this finding. CONCLUSIONS: The decrease in NO metabolites occurred irrespective of stored RBC transfusions, suggesting this decrease may be related to blood loss during surgery and hemodilution rather than to scavenging of NO or inhibition of NO synthesis by stored RBC transfusions.

Clinical scoring scales in thyroidology: A compendium.

This compendium brings together traditional as well as contemporary scoring and grading systems used for the screening and diagnosis of various thyroid diseases, dysfunctions, and complications. The article discusses scores used to help diagnose hypo-and hyperthyroidism, to grade and manage goiter and ophthalmopathy, and to assess the risk of thyroid malignancy.