Submandibular masses

Echogenic line is the Intraglandular DUct
H - myelohyoid; D - Belly of Diagastric
s:- Submandibular gland


small White arrow -Whartons Duct; Large white arrow, mylohyoid muscle


P, parotid gland; White arrow, Küttner lymph node; R, retromandibular vein; S, submandibular gland


There is a non-obstructing intraductal calculus within Wharton's duct casting an acoustic shadow (large white arrow), together with sludge. S, submandibular gland


submandibular abscess --. There is an ill-defined intraglandular hypoechoic mass and adjacent enlarged reactive lymph node (white arrow). Under ultrasound guidance pus was aspirated and subsequent culture grew Staphylococcus aureus. S, submandibular gland.

tuberculous abscess. There is a complex mass (callipers) in the submandibular gland with a central necrotic abscess cavity. Excision confirmed involvement of the gland with
Mycobacterium tuberculosis.


chronic sialadenitis secondary to stone disease. S, atrophic, hypoechoic, irregular gland. Note the associated intraglandular calculus (callipers).



Küttner tumour. There is a well-defined, hypoechoic mass in the submandibular gland, which could be mistaken, clinically and sonographically for a tumour. Diagnosis of chronic inflammation was confirmed by core biopsy and subsequent excision. Incresed Doppler

sarcoid granulomata



Sjögren's syndrome. The gland is diffusely enlarged and of heterogeneous echotexture. Note the hypoechoic foci within the gland representing early sialectatic chang
numerous prominent cystic spaces typical of florid sialectasis in Sjögren's syndrome. A similar appearance can occur in HIV infection.


submandibular gland pleomorphic adenoma. This lesion appears rounded, well defined and hypoechoic with distal acoustic enhancement present.


Oncocytoma




intraglandular adenoid cystic carcinoma. This appears as an ill-defined, hypoechoic and inhomogeneous mass.



mucoepidermoid carcinoma (large white arrow). Sonographically the features shown are similar to the adenoid cystic carcinoma in Note that in this case there is also extraglandular extension of tumour with invasion of the subcutaneous tissues and skin (small white arrows).



lymphoma of the submandibular gland

------------------------------------------------
Pretty much the whole article:=
British Journal of Radiology (2005) 78, 362-369

Parathyroid Embryology

Descent of the lower parathyroid. Whereas the upper parathyroid occupies a relatively constant position in relation to the middle or upper third of the lateral thyroid lobe, the lower parathyroid normally migrates in embryonic life and may end up anywhere along the course of the dotted line. When this gland is in the chest, it is nearly always in the anterior mediastinum.

Focal thyroid FDG-PET incidentaloma

Occasionally, a patient may be referred for an incidental thyroid nodule noted only on 18-fluorodeoxyglu-cose positron-emission tomography (FDG-PET) scan obtained for another purpose, usually evaluation of another known or suspected malignancy.

Among a group of 32 patients with a focal thyroid FDG-PET incidentaloma who then underwent FNAB, 16 (50%) were found to be malignant — 14 were papillary thyroid carcinoma and 2 were metastatic from breast and esophagus.^[61]

Thus, thyroid incidentalomas identified on FDG-PET scan have a high risk of malignancy and thus should be evaluated further, starting with FNAB.

------------------------------------------
SURGERY: Volume 138, Issue 6, Pages 1166-1175 (December 2005)

Fifteen of 48 lesions were malignant and 33 were benign. Nine of 15 malignant lesions were 18FDG-avid (sensitivity 60%). Thirty of 33 benign lesions were 18FDG-cold (specificity 91%). Positive and negative predictive values were 75% and 83%, respectively.

^{18FDG-PET/CT provides a high negative predictive value for malignancy, making this a potentially useful tool in the evaluation of thyroid nodules with indeterminate fine-needle aspiration. However further studies with larger sample sizes are needed to determine the true efficacy of this test.}

Adrenal Lesion SUV on PET-CT

The SUV_max for each adrenal nodule was recorded by drawing a rectangular three-dimensional region of interest around the nodule. Verification that the location of the demarcated SUV_max pixel resided within the adrenal nodule was performed by viewing the fused images. The rectangular region of interest was adjusted to exclude adjacent FDG-avid structures.

The average liver SUV (SUV average) for each patient was recorded by drawing a 90-cm³ rectangular three-dimensional region of interest centered within the right hepatic lobe. Care was taken to exclude any abnormalities, portions of the gallbladder, and the fissure of the ligamentum teres. The liver SUV average could not be measured in one patient because of extensive intrahepatic metastases. The adrenal SUV_max was divided by the liver SUV average to calculate a ratio (SUV ratio) for each nodule.

Conclusion: Definitive identification of many metastases can be accomplished by applying an SUV ratio cutoff of greater than 2.5, allowing pragmatic management of adrenal nodules that initially test positive with the combined PET/CT criteria SUV_max > 3.1 and mean attenuation > 10 HU.

• We found that recent proposed thresholds of nodule maximum standardized uptake value (SUV_max) greater than 3.1 and nodule SUV ratio (ratio of nodule SUV_max to liver SUV average) greater than 1.0 had the same sensitivity; however, the SUV_max threshold was more specific and yielded fewer false-positive results.
  
• Combined PET/CT has improved accuracy compared with PET alone when using a mean attenuation threshold of greater than 10 HU; however, lipid-poor fluorine 18 fluorodeoxyglucose (FDG)-avid adrenal adenomas lead to a high number of false-positive findings.
  
• Further application of a high SUV ratio threshold of greater than 2.5 separated many true-positive metastases from false-positive FDG-avid adrenal adenomas.

• The proposed algorithm refines the evaluation of adrenal nodules with PET/CT when staging disease in patients known to have or suspected of having lung cancer.
  
• The proposed algorithm allowed definitive characterization of 72 (76%) of 95 adrenal nodules found at PET/CT and can therefore spare some patients from undergoing further imaging or interventions.

----------------------------------------------------------------------------------

Adrenal Nodules at FDG PET/CT in Patients Known to Have or Suspected of Having Lung Cancer: A Proposal for an Efficient Diagnostic Algorithm¹

Matthew J. Brady, MD, John Thomas, MBBS, Terence Z. Wong, MD, Kendra M. Franklin, MD, Lisa M. Ho, MD, and Erik K. Paulson, MD

¹ From the Department of Radiology, Duke University Medical Center, Erwin Rd, Durham, NC 27710. From the 2007 RSNA Annual Meeting. Received February 1, 2008; revision requested April 2; revision received June 17; accepted July 1; final version accepted August 29. Address correspondence to M.J.B., Roper Radiologists, PA, 316 Calhoun St, Charleston, SC 29401.

Iodine Allergy and I-131 Treatment

True Iodine Allergy - Extremely rare (Some debate its Existence)

So called 'Iodine Allergy' is usually a reference to Allergic reaction to Iodinated Contrast or Shellfish. The allergic reaction is to the protein molecule or organic molecule that is bound to the iodine. Iodine-131 Treatment can be safely given to these patients

Fetal Nasal Bone Length

Median Normal nasal bone lengths :

2.3 (range, 1.5–3.2), mm between 77 and 83 days’ gestational age- 11-12 Weeks
2.6 (range, 1.4–4.2), mm between 84 and 90 days’ gestational age- 12-13 Weeks
2.9 (range, 2.1–3.8) mm between 91 and 98 days’ gestational age - 13-14 Weeks

Absent Nasal Bone High Correlation with Downs