Correct answer is: Know infant hip anatomy

Discussion

In this image, we can see a Type IV Graf dislocated hip with a poor bony roof, a flattened superior bony rim and with the cartilaginous roof pressed downwards. The angles are immeasurable in this case. By simply knowing the anatomy you are able to diagnose the hip dislocation.

We cannot measure the angles and draw the lines in this case because it is a decentered joint. Before a hip sonogram can be evaluated you must identify the anatomical structures in a methodical way (chondro-osseous junction, femoral head, synovial fold, joint capsule, acetabular labrum, cartilage acetabular roof, bony socket and osseous rim) (1). In order to reach a diagnostic and measurable sonogram the three landmarks must be present (the formed acetabular roof, bony part of the acetabular roof and bony rim: turning point from concavity to convexity).

One of the main advantages of the Graf method is that it can be used as a criterion of improvement, stagnation or worsening of the condition during the follow-up of patients treated with Pavlik harness (2, 3). In this case, the infant had a dislocated hip, and after 3 weeks of treatment, this is the sonographic result:

In 6 weeks, 9 weeks and 12 weeks, the favorable evolution of the case can be observed, starting from a type IV to a type Ia hip, or from a dislocated hip to a mature hip.

Image 5: The first step: anatomical identification. Subtitles:
1-Femoral head
2-Large trochanter
3-Bony roof
4-Medial border of the Ilium
5-Labrum
6-Cartilaginous acetabular roof
7-Joint capsule
8-Synovial fold
9-Triradiate cartilage

Take home message

Through accurate analysis of the pathological changes in the cartilage and bony socket it is possible to state the severity of the pathology affecting the hip joint, even before the confirmation by the fourth step (the measurement with alpha and beta angles). Always remember the order of assessment: the first step is the anatomical identification, the second step is checking the three landmarks, the third step is the description of the structures (bony socket, bony rim and cartilaginous acetabular roof), and finally, the last one is the angles’ measurement that it must coincide (be congruent).

References

1. GRAF, Reinhard.Hip sonography: diagnosis and management of infant hip dysplasia. Springer Science & Business Media, 2006.
2. KOSAR, Pinar et al. Follow‐up SonographicResults for Graf Type 2a Hips: Association With Risk Factors for Developmental Dysplasia of the Hip and Instability.Journal of Ultrasound in Medicine, v. 30, n. 5, p. 677-683, 2011.
3. JUDD, Julia; CLARKE, Nicholas MP. Treatment and prevention of hip dysplasia in infants and young children.Early human development, v. 90, n. 11, p. 731-734, 2014.

Correct answer to Q1 is:

1. B-line artefacts
2. Irregular pleural line and very small amount of free fluid located peripherally
3. Multiple small consolidations in all lung regions

Correct answer to Q2 is:

1. SARS-CoViD-19 infection

Discussion:

Since COVID-19 infection is primarily a respiratory disease the expectation would be that lung imaging would be essential for the diagnosis (1,2). The typical sonographic signs using lung US (LUS) identified in the course of COVID-19 infections include features of the pleura and pleural space (1), findings of interstitial pneumonia (2) and specific artefacts (3) (1,3-5). The signs are specific when there is a very high “a priori” probability of COVID-19 with cough and dyspnea (1). The initial lung involvement often posterior-basal may become extensive with involvement of the entire lung as shown in this patient. In later stages mixed and much less specific image patterns can be observed including the so-called white lung and bacterial pneumonia superinfection. US also allows detection of complications including pneumothorax, not only in ventilated patients, and pulmonary embolism (5).

Ultrasound signs and differential diagnoses

Pleura

• Thickened, irregular (coarse) and fragmented pleural line.
• Small amount of superficially located pleural fluid (sign of severity). More extensive pleural effusions are not typical.

Lung

• Consolidations, multiple. Very small consolidations often posterobasally, initially. Later in various distributions and possibly involving the entire lung.

Artefacts

• B-lines (initially discrete, later multifocal and confluent), alveolar-interstitial syndrome, so-called „white lung“ (ARDS).
• Respiratory dependent lung sliding (A-artefact), combined with B-line artefacts (mixing A and B patterns).

Differential diagnoses and complications

• Chronic heart insufficiency (BLA, larger pleural effusion than in CoViD-19).
• Bacterial pneumonia (typically larger consolidations than in CoViD-19).
• Pulmonary embolism (initially no vascularity)

Conflicts of interest

“The authors declare no conflict of interest.”

Image(s): Confluent curtain like B-line artefacts (BLA) intercostally using 5 MHz curved array transducer (a). Thickened and irregular pleura line and tiny amount of pleural fluid using 5 MHz curved array transducer (b) and 10 MHz transducer revealing much more details (c). The corresponding computed tomography image is also shown (d). C: Consolidation. FF: free fluid. White arrow: Pneumo-alveolo-bronchogram.

References

1. Piscaglia F, Stefanini F, Cantisani V, Sidhu PS, Barr R, Berzigotti A, Chammas MC, et al. Benefits, Open questions and Challenges of the use of Ultrasound in the COVID-19 pandemic era. The views of a panel of worldwide international experts. Ultraschall Med 2020;41:228-236.
2. Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, Zhao X, et al. A Novel Coronavirus from Patients with Pneumonia in China, 2019. N Engl J Med 2020;382:727-733.
3. Dietrich CF, Mathis G, Cui XW, Ignee A, Hocke M, Hirche TO. Ultrasound of the pleurae and lungs. Ultrasound Med Biol 2015;41:351-365.
4. Dietrich CF, Mathis G, Blaivas M, Volpicelli G, Seibel A, Atkinson NS, Cui XW, et al. Lung artefacts and their use. Med Ultrason 2016;18:488-499.
5. Dietrich CF, Mathis G, Blaivas M, Volpicelli G, Seibel A, Wastl D, Atkinson NS, et al. Lung B-line artefacts and their use. J Thorac Dis 2016;8:1356-1365.

Correct answer to Q1 is:

1. B-line artefacts
2. Irregular pleural line and very small amount of free fluid located peripherally
3. Multiple small consolidations in all lung regions

Correct answer to Q2 is:

1. SARS-CoViD-19 infection

Discussion:

Since COVID-19 infection is primarily a respiratory disease the expectation would be that lung imaging would be essential for the diagnosis (1,2). The typical sonographic signs using lung US (LUS) identified in the course of COVID-19 infections include features of the pleura and pleural space (1), findings of interstitial pneumonia (2) and specific artefacts (3) (1,3-5). The signs are specific when there is a very high “a priori” probability of COVID-19 with cough and dyspnea (1). The initial lung involvement often posterior-basal may become extensive with involvement of the entire lung as shown in this patient. In later stages mixed and much less specific image patterns can be observed including the so-called white lung and bacterial pneumonia superinfection. US also allows detection of complications including pneumothorax, not only in ventilated patients, and pulmonary embolism (5).

Ultrasound signs and differential diagnoses

Pleura

• Thickened, irregular (coarse) and fragmented pleural line.
• Small amount of superficially located pleural fluid (sign of severity). More extensive pleural effusions are not typical.

Lung

• Consolidations, multiple. Very small consolidations often posterobasally, initially. Later in various distributions and possibly involving the entire lung.

Artefacts

• B-lines (initially discrete, later multifocal and confluent), alveolar-interstitial syndrome, so-called „white lung“ (ARDS).
• Respiratory dependent lung sliding (A-artefact), combined with B-line artefacts (mixing A and B patterns).

Differential diagnoses and complications

• Chronic heart insufficiency (BLA, larger pleural effusion than in CoViD-19).
• Bacterial pneumonia (typically larger consolidations than in CoViD-19).
• Pulmonary embolism (initially no vascularity)

Conflicts of interest

“The authors declare no conflict of interest.”

Image(s): Confluent curtain like B-line artefacts (BLA) intercostally using 5 MHz curved array transducer (a). Thickened and irregular pleura line and tiny amount of pleural fluid using 5 MHz curved array transducer (b) and 10 MHz transducer revealing much more details (c). The corresponding computed tomography image is also shown (d). C: Consolidation. FF: free fluid. White arrow: Pneumo-alveolo-bronchogram.

References

1. Piscaglia F, Stefanini F, Cantisani V, Sidhu PS, Barr R, Berzigotti A, Chammas MC, et al. Benefits, Open questions and Challenges of the use of Ultrasound in the COVID-19 pandemic era. The views of a panel of worldwide international experts. Ultraschall Med 2020;41:228-236.
2. Zhu N, Zhang D, Wang W, Li X, Yang B, Song J, Zhao X, et al. A Novel Coronavirus from Patients with Pneumonia in China, 2019. N Engl J Med 2020;382:727-733.
3. Dietrich CF, Mathis G, Cui XW, Ignee A, Hocke M, Hirche TO. Ultrasound of the pleurae and lungs. Ultrasound Med Biol 2015;41:351-365.
4. Dietrich CF, Mathis G, Blaivas M, Volpicelli G, Seibel A, Atkinson NS, Cui XW, et al. Lung artefacts and their use. Med Ultrason 2016;18:488-499.
5. Dietrich CF, Mathis G, Blaivas M, Volpicelli G, Seibel A, Wastl D, Atkinson NS, et al. Lung B-line artefacts and their use. J Thorac Dis 2016;8:1356-1365.

Correct answer is: Leukemia

Image Findings:

The examination revealed an enlarged, heterogeneous right testicle, with a normal epididymis. Also, a small homogenous fluid collection, corresponding to a hydrocele was seen (Figure 1 and 2). The color Doppler study showed a pattern of hypervascularity.

Discussion

Leukemia is a cancer of the body’s blood-forming tissues, such as the bone marrow and the lymphatic system. Leukemia can affect adults and children. In acute lymphocytic leukemia, the brain and the spinal cord and the testes in boys are known as sanctuary sites of cancer. Sanctuary sites are extramedullary anatomic locations that have historically been difficult to penetrate with systemic chemotherapy. In the testes, the finding of an enlarged firm testicle and hyperactivity on color Doppler similar to inflammatory findings, should remind the physician of leukemia of the testis.

Teaching Points

Although an enlarged testicle due to leukemia is a rare ultrasound finding, it is important to remember this diagnosis when dealing with a patient with a previous history of leukemia. The differential diagnoses include inflammatory diseases, but the clinical finding of a painless testicle is very important, as this indicates leukemia more than inflammation.

References

1. https://radiopaedia.org/articles/leukaemia-testicular-manifestations-1?lang=us
2. Kocakroc E, Bhatt S, Dogra V S; Ultrasound Evaluation of Testicular neoplasms. Ultrasound Clinics (2), 27-44, 2007.
3. Dogra V, Gottlieb RH, Oka M et al. Sonography of scrotum. Radiology, 227:18-36, 2003.
4. Hortsman WG, Melson GL, Middleton WD et al. Testicular tumors: findings with color Doppler US. Radiology, 185: 733 -37, 1992.

Correct answer is: Intrathyroidal thymic tissue

Explanation:

In the images, we see a nodule with ill-defined margins and multiple hyperechoic foci similar to microcalcifications, which matched the sonographic appearance of the normal eutopic thymus, in the mid-portion of the right thyroid lobe. Color Doppler sonography showed scanty blood flow within the nodule. 

Intrathyroidal thymic tissue is a rare benign lesion found in the pediatric thyroid gland of nonthyroid origin and may be confused with a malignant thyroid nodule because of the hyperechoic dots mimicking microcalcifications (1-3).

Solitary thyroid nodules in children are present in 0.2%-1.5% (4) in comparison to the higher prevalence in adults. The probability of malignancy in children is higher than in adults (3). The accurate ultrasound diagnosis of such lesions is critical to avoid unnecessary biopsy or surgery. Most lesions identified within the thyroid gland in children are benign nodules of follicular cell origin or, rarely, differentiated thyroid cancers (6). The sonographic findings that suggest a malignant thyroid nodule are marked hypoechogenicity, irregular margins, microcalcifications, and a taller-than-wide shape.

Take Home Message

Solitary thyroid nodules in children are rare.
In ultrasound of the thyroid you must also assess the lymph nodes and the rest of the neck, especially the thymus in children. A good exam can avoid unnecessary biopsy or surgery.

References

1. BÜYÜKYAVUZ, I. et al. Ectopic thymic tissue as a rare and confusing entity. European journal of pediatric surgery, v. 12, n. 05, p. 327-329, 2002.
2. http://www.pathologyoutlines.com/topic/thyroidthymictissue.html
3. FRATES, Mary C. et al. Ectopic intrathyroidal thymic tissue mimicking thyroid nodules in children. Journal of Ultrasound in Medicine, v. 37, n. 3, p. 783-791, 2018.
4. PARK, So Hyun et al. Intrathyroidal thymic tissue mimicking a malignant thyroid nodule in a 4-year-old child. Ultrasonography, v. 33, n. 1, p. 71, 2014.
5. O’CONNOR, Kelly et al. An ectopic intrathyroidal thymic tissue and intrathymic parathyroid tissue in a patient with Graves disease. Gland surgery, v. 6, n. 6, p. 726, 2017.
6. HUANG, Yanlei; ZHENG, Shan; XIAO, Xianmin. Ectopic intrathyroidal thymus in children: two case reports and review of the literature. Journal of Pediatric Surgery Case Reports, v. 1, n. 11, p. 386-390, 2013.