Correct answer to Q1 is: Abnormal lymph nodes either due to abscess or malignancy.

Due to the inconclusive ultrasound examination the patient was referred to a CT of the abdomen as well as further blood samples at the department of infectious diseases. The CT was inconclusive too, and a fine needle aspiration of the lymph nodes (FNA) was suggested.

Correct answer to Q2 is: Tularemia.

Discussion:

Tularemia is a zoonosis caused by Francisella tularensis, a small aerobe gram-negative rod. Tularemia is very rare in northern Europe, with under 10 cases per year in Denmark. The most common disease vectors are rabbits and wild game, but ticks and mosquitoes can also carry and spread the infection. Typical symptoms include fever, muscle soreness, fatigue and lymphadenopathy. Diagnosis is usually confirmed using PCR or microbial culturing of samples. Oral antibiotics are effective, and complications are rare with adequate treatment. [1]

In the present case, ultrasound revealed an ovoid lymph node of moderate size, with no lobulation and no clear effacement of the hilum – typical traits of benign lymphadenitis [2]. However, the node had areas of considerable hypoechogenicity (see image 4), which is typically seen in areas of abscessing infection, or of necrosis in metastatic lymph nodes, especially in malignant melanoma. A lymph node with metastasis of malignant melanoma is typically hypoechoic and round, and the hilum may be effaced. The shape may also be irregular or lobulated. [3] When ultrasound reveals a lymph node exhibiting one or more of these traits, biopsy should be considered in order to rule out malignancy.

In the current case, purulent exudate was sampled from the lesion and cytology was not performed, as PCR soon confirmed infection with Francisella tularensis. The patient was treated with oral antibiotics, and the symptoms quickly subsided with no further complications.

As an interesting sidenote, because of the potential of Francisella tularensis to cause pulmonary tularemia through infection using aerosols, the Center for Disease Control considers tularemia to be a potential biological weapon threat. [4]

Conflicts of interest

“The authors declare no conflict of interest.”

References

1. Tularæmi (harepest) Available online: https://www.ssi.dk/sygdomme-beredskab-og-forskning/sygdomsleksikon/t/tularaemi (accessed on Dec 13, 2020).
2. Vassallo, P.; Wernecke, K.; Roos, N.; Peters, P.E. Differentiation of benign from malignant superficial lymphadenopathy: The role of high-resolution US. Radiology 1992, 183, 215–220.
3. Patnana, M.; Bronstein, Y.; Szklaruk, J.; Bedi, D.G.; Hwu, W.J.; Gershenwald, J.E.; Prieto, V.G.; Ng, C.S. Multimethod imaging, staging, and spectrum of manifestations of metastatic melanoma. Clin. Radiol. 2011, 66, 224–236.
4. CDC Tularemia | Emergency Preparedness & Response Available online: https://emergency.cdc.gov/agent/tularemia/ (accessed on Dec 13, 2020).

Correct answer is: Testicular tumor

Fig. 5

Ultrasound demonstrated an enlarged right testicle of128 ml (Fig. 1 and 2). The parenchyma was hypoechoic and heterogeneous, with small calcifications and regular contours (Fig. 3). Doppler imaging showed increased vascularization (Fig.4). Due to the suspicion of a testicular tumor in the scrotum, an abdominal ultrasound was also performed. This revealed a hypoechoic 4.6cm tumor with irregular contours in the right para-aortic region –just above the aortoiliac bifurcation –highly suspect of a metastatic lymph node (Fig.5).

Discussion

A testicular tumor should be suspected when an ultrasound shows a solid intratesticular mass with internal vascularization. It is essential to evaluate extra-testicular sites for lymph node metastases as disseminated metastases from testicular cancer may be seen here before the testiculartumor is identified(1). Especially, the retroperitoneal lymph nodes nearthe abdominal aorta should be examinedcarefully, as it is the main site for lymphatic spread(2). Infarction and hematoma are also relevant differential diagnoses when a mass is seen; however, no Doppler flow will be seen. In the case of infection, we would see an increase in Doppler flow in the affected testicle, but without the presence of a mass(3).

Teaching Points

The gold standard test for initial detection of testicular tumoris ultrasound, with a sensitivity close to 100% and specificity of 95-99%(3,4). Extra-testicular evaluation should be encouraged when malignancy is suspected.

Figure Legends

Figure 1 and 2 -Scrotal ultrasound performed with a linear transducer in the transversal plane (Fig. 1) and longitudinal plane (Fig. 2) demonstrated an enlarged right testicle with hypoechoic and diffuse heterogeneous echotexture and small hyperechoic focicorresponding tomicrocalcifications.

Figure 3 -Presence of a hyperechoic lesioninside the right testicle, suggestive of calcification (arrow).

Figure 4 -Scrotal ultrasound performed with a convex array transducer in the longitudinal plane demonstrated a diffuse increase in vascularization of the right testis on amplitude Doppler.

Figure 5 -Abdominal ultrasound performed with a convex array transducer, cross-section,showing the image of a right para-aortic lymph node, with loss of normal architecture, irregular contours (arrow) and the aorta (arrowhead).

References

1. Moreno CC, Small WC, Camacho JC, et al. Testicular Tumors: What Radiologists Need to Know—Differential Diagnosis, Staging, and Management. RadioGraphics 2015; 35:400–415.
2. Marko J, Wolfman DJ, Aubin AL, Sesterhenn IA. Testicular Seminoma and Its Mimics. RadioGraphics 2017;37:1085–1098.
3. S. Gallego García, C. Santos Montón, I. Alonso Diego, et al. Testicular tumors: ultrasound diagnosis. European Society of Radiology. ECR 2019 / C-0935. 2019. DOI: 10.26044/ecr2019/C-0935
4. Sumat K, Rumana M and Parveen Shah. Clinicopathological Characteristics of Testicular Tumors. Medwin Publishers. Clinical Pathology 2017, 1(1): 000106

Correct answer is: Dermoid cyst

Dermoid cysts account for 15% of all ovarian neoplasms and predominate in young women, being the most common ovarian neoplasm in patients younger than 20 years. Ultrasound is the preferred imaging modality. Typically, an ovarian dermoid is seen as a unilocular cystic adnexal mass with some mural components. The spectrum of sonographic features includes: a diffusely or partially echogenic mass with posterior sound attenuation owing to sebaceous material and hair within the cyst cavity; an echogenic interface at the edge of the mass that obscures deep structures (the tip of the iceberg sign); mural hyperechoic or Rokitansky nodule (dermoid plug); echogenic shadowing calcific or dental (tooth) components; fluid-fluid levels; multiple thin echogenic bands caused by the hair in the cyst cavity; the dot-dash pattern (dermoid mesh); no internal vascularity on color Doppler; intracystic floating balls sign (uncommon, but characteristic).

Discussion

Among the alternatives, the diagnosis of dermoid cyst should be considered because ovarian serous or mucinous cystadenoma/cystadenocarcinoma is usually only a serious consideration if the typical features of dermoid cyst are absent. Carcinoma also tends to occur in an older age group than dermoid cysts. Ovarian dysgerminomas are rare ovarian tumors that occur predominantly in young women in the 2nd to 3rd decades. Approximately 10-20% of cases occur in pregnancy. On ultrasound, they may be seen as a septated ovarian mass with varying echotexture. Color Doppler ultrasound may show prominent flow signal within the fibrovascular septa. Fibromas occur at all ages but are most frequently seen in middle-aged women, and on ultrasound manifest as solid, hypoechoic masses with ultrasound beam attenuation. As such, they may appear similar to a pedunculated subserosal uterine fibroid. However, the sonographic appearance can be variable, and some tumors can have cystic components, although rarely.

Take home message

Knowing the ultrasound aspects of dermoid cysts is important because they are benign lesions that grow slowly (1-2 mm per year) and, therefore may not need surgery. The most common complication is ovarian torsion, which occurs in 3-16% of dermoid cysts. Many recommend annual follow-up for lesions <7 cm to monitor growth. Tumors larger than 7 cm should be resected.

References

1. Outwater EK, Siegelman ES, Hunt JL. Ovarian teratomas: tumor types and imaging characteristics. Radiographics. 21 (2): 475-90
2. Adusumilli S, Hussain HK, Caoili EM et-al. MRI of sonographically indeterminate adnexal masses. AJR Am J Roentgenol. 2006;187 (3): 732-40.
3. Gürel H, Gürel SA. Ovarian cystic teratoma with a pathognomonic appearance of multiple floating balls: a case report and investigation of common characteristics of the cases in the literature. Fertility and sterility. 90 (5): 2008.e17-9.
4. Acién P, Ruiz-Maciá E, Acién M, Martín-Estefanía C. Mature ovarian teratoma-associated limbic encephalitis. Journal of obstetrics and gynaecology : the journal of the Institute of Obstetrics and Gynaecology. 35 (3): 317-9.
5. Patel MD, Feldstein VA, Lipson SD et-al. Cystic teratomas of the ovary: diagnostic value of sonography. AJR Am J Roentgenol. 1998;171 (4): 1061-5
6. Park SB, Kim JK, Kim KR et-al. Imaging findings of complications and unusual manifestations of ovarian teratomas. Radiographics. 28 (4): 969-83.
7. Moomjian LN, Clayton RD, Carucci LR. A Spectrum of Entities That May Mimic Abdominopelvic Abscesses Requiring Image-guided Drainage. (2018) Radiographics : a review publication of the Radiological Society of North America, Inc. 38 (4): 1264-1281.

Correct answer is: Passive hepatic congestion.

Discussion

The figures show a slightly enlarged liver with regular contours and blunt edges. The liver echogenecity is homogeneous. There are no focal lesions. Enlarged hepatic veins, measuring 1.3 to 2 cm near the IVC. Enlarged portal vein with a diameter of 1.5 cm and without thrombi.

Passive hepatic congestion, also known as congested liver in cardiac disease, describes the stasis of blood in the hepatic parenchyma, due to impaired hepatic venous drainage, which leads to the dilation of the central hepatic veins and hepatomegaly. Passive hepatic congestion is a well-studied result of acute or chronic right-sided heart failure.

The spectrum of sonographic features includes enlargement of the right hepatic lobe and the right hepatic vein measures about 9 mm (normal caliber < 6 mm), increases up to 13 mm with pericardial effusion, dilated IVC/hepatic veins, hepatomegaly, ± ascites.

Expected findings related to alternative answers

Among the alternatives, the diagnosis of congestive hepatic congestion should be considered by the patient history and the imaging findings. Budd-Chiari syndrome refers to the clinical picture that occurs when there is partial or complete obstruction of the hepatic veins. It is characterized on imaging by ascites, caudate hypertrophy, peripheral atrophy and prominent collateral veins. Hepatic veno-occlusive disease (VOD), also known as sinusoidal obstruction syndrome (SOS), is a condition arising from occlusion of the hepatic venules. Ultrasound is the imaging modality of choice which may show: hepatomegaly; portal vein abnormalities, such as portal vein dilatation, portal venous pulsatility, hepatofugal portal venous flow; gallbladder wall thickening (> 6-8 mm); and ascites. Acute hepatitis is a clinical diagnosis and the spectrum of sonographic features includes hepatomegaly (most sensitive sign) >15.5 cm at the midclavicular line; starry sky appearance; gallbladder wall thickening; periportal edema; accentuated brightness of the portal veinous walls; overall decreased echogenicity.

Take home message

Knowing the ultrasound aspects of hepatic congestion is important because it allows the clinician to direct the treatment to the basic cause – the heart failure.

References

1. Zakim D, Boyer TD. Hepatology. Saunders. ISBN:0721648363.
2. McNaughton DA, Abu-Yousef MM. Doppler US of the liver made simple. RadioGraphics 2011; 31(1): 161–188.
3. Gore RM, Mathieu DG, White EM et-al. Passive hepatic congestion: cross-sectional imaging features. AJR Am J Roentgenol. 1994;162 (1): 71-5.
4. Murphy FB, Steinberg HV, Shires GT et-al. The Budd-Chiari syndrome: a review. AJR Am J Roentgenol. 1986;147 (1): 9-15
5. Bayraktar UD, Seren S, Bayraktar Y. Hepatic venous outflow obstruction: three similar syndromes. World J. Gastroenterol. 2007;13 (13): 1912-27
6. Brancatelli G, Vilgrain V, Federle MP et-al. Budd-Chiari syndrome: spectrum of imaging findings. AJR Am J Roentgenol. 2007;188 (2): W168-76

Correct answer is: Medial tibial plateau stress fracture.

Discussion

Stress fractures of the lower limb are not an uncommon finding in runners. This may be due to an increase in load or training errors. They may also occur due to decreased bone density of individuals without necessarily any increase in loading.

Our patient indicated an increase in loading along with tenderness over medial tibial plateau. On ultrasound assessment oedema of the fat layer overlying bone was noted along with periosteal haematoma which is shown as a hypoechoic line overlying the bone cortex (this is nicely shown in video 1 and Image 4). Swelling and oedema of the overlying fat can be noted on Image 1 between the medial collateral ligament and tibia. Clinical history and examination along with ultrasound findings are strongly indicative of stress fracture.

Image 4- Medial tibial plateau transverse view. Tibia (open white arrow), deep fascia (white arrow), periosteal haematoma (black arrow). Associated fat oedema can be noted overlying periosteal haematoma.

Image 3- PDFS MRI sequence showing bone marrow oedema of tibial plateau consistent with stress fracture.

Expected findings related to alternative answers

1. A) Pes anserine bursitis-very rare to occur in isolation and swelling in this region can usually be attributed to one of the other 3 possible answers.
2. B) Medial meniscal tear-clinically would present with pain and tenderness centred more over medial joint line rather than pes anserine region. Fluid and oedema uncommonly seen tracking down towards the pes anserine region due to a related meniscal cyst with or without rupture. Periosteal haematoma would not be present.
3. D) Pes anserine bursitis may occur in patients with systemic arthropathy. This would result in localised swelling of tissues between medial collateral ligament (MCL) and pes anserine (unlike our current case which shows swelling under MCL).

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.

Correct answer is: Bilateral Tessier Type 3

Click here to view after photos after birth >>

Explanation:

This is a bilateral Tessier type 3 because the cleft is from the nasal alar up to the medial orbit bilaterally. However, this is a rare case of Type 3 because the upper lip and the maxilla are intact.

Facial cleft – also called craniofacial cleft – is one of the most commonly arising non‐lethal congenital abnormalities. The worldwide incidence ranges between 1 and 2.2/1000, depending on the geographical region [1].

The classification proposed by Tessier uses the numbers from 0 to 14 depending on the location of a cleft in relation to the median facial line. Clefts number 0 to 6 are craniofacial defects, while clefts number 8 to 14 are cerebrocranial defects [2]. The classification is simple, logical and has been widely accepted due to the precise description of a defect and facilitation of comparison of various defects between centers.

References

[1] Moore, MH. Rare craniofacial clefts. The Journal of Craniofacial Surgery 1996; 7 (6): 408–11.

[2] Tessier P. Anatomical classification of facial, cranio-facial and latero-facial clefts. Journal of Maxillofacial Surgery 1976; 4 (2): 69–92.

Correct answer is:

Relapsed Grynfelt lumbar hernia.

Explanation:

Lumbar hernia is characterized by the presence of a failure in the transversal fascia or aponeurosis of the transverse muscle of the abdomen that results in the extrusion of intra-abdominal content through the defect in the posterolateral abdominal wall.

Lumbar hernias are quite rare, have a higher prevalence in males (about 2/3 of all reported cases) and the majority are unilateral, being twice as common on the left side than on the right side [1; 2]. Most diagnosed patients are in the sixth to seventh decade of life. [3, 4] There is a higher prevalence of lumbar hernias located in the upper lumbar triangle, probably because it is larger and located in a region with weaker musculature than the lower triangle [2].

The lumbar region can be anatomically defined as the area of the abdominal wall lateral to the midclavicular line, between the subcostal plane and the plane that connects the tubercles of the iliac crests.

Lumbar hernias are classified as superior or inferior according to their anatomical location. The upper lumbar or Grynfelt hernia is the one that appears through the anatomical triangle delineated superiorly by the 12th rib, laterally by the external oblique muscle, inferiorly by the internal oblique muscle and medially by the erector spinae muscle. [1, 5]

The lower lumbar or Petit’s hernia is located in the lower triangle, limited inferiorly by the iliac crest, medially by the latissimus dorsi muscle and laterally by the external oblique muscle [1, 5].

The diagnosis is suspected by clinical and physical examination, and may be confirmed by imaging methods such as ultrasound, computed tomography or magnetic resonance imaging. Like other types of hernias, lumbar hernias can evolve with complications such as incarceration and necrosis of intestinal loops [6]. In the present case, the patient presented recurrence after herniorrhaphy with mesh placement.

Take Home Message

Although lumbar hernias are very rare, it is an important differential diagnosis to remember. The suspected clinical diagnosis can be confirmed by ultrasound with high accuracy.

References

1.Heniford BT, Iannitti DA, Gagner M. Laparoscopic inferior and superior lumbar hernia repair. Arch Surg 1997;132: 1141-4.

2.Zhou X, Nve JO, Chen G (2004) Lumbar hernia: clinical analysis of 11 cases. Hernia 8:260–263.

3.Sharma, Lt Col P (2009) Lumbar hernia. MJAFI 65:178–179. 42.Baker ME, Weinerth JL, Andriani RT et al (1986) Lumbar hernia: diagnosis by CT. AJR Am J Roentgenol 148:565–567.

4.Baker ME, Weinerth JL, Andriani RT et al (1986) Lumbar hernia: diagnosis by CT. AJR Am J Roentgenol 148:565–567.

5. Stamatiou D, Skandalakis JE, Skandalakis LJ, Mirilas P. Lumbar hernia: surgical anatomy, embryology, and technique of repair. American Surgeon. 2009;75(3):202–207.

6. Christiano Marlo Paggi CLAUS1,2, Lucas Thá NASSIF1 , Yan Sacha AGUILERA. Reparo Laparoscópico de hérnia lombar (GRYNFELT): Descrição ténica. 2017;30(1):56-59.

Correct answer is:

Left portal vein -> umbilical vein/paraumbilical vein -> superior epigastric vein -> internal thoracic vein -> brachiocephalic vein -> superior vena cava

Explanation:

In the context of portal hypertension, the umbilical vein undergoes recanalization and, as well as the paraumbilical veins that run with it in the falciform and round ligaments, have their flow inverted, from the peripheral portal branches of the left hepatic lobe towards the epigastric veins. From there the blood goes in cranial direction (superior epigastric vein – internal thoracic vein – brachiocephalic vein – superior vena cava) or caudal (inferior epigastric vein – external iliac vein – common iliac vein – inferior vena cava) to achieve the ultimate goal which is the arrival of blood to the heart, deviating from the liver.

Discussion of the image interpretation leading to the diagnosis compared to the alternative answers

Doppler demonstration of hepatofugal flow in the umbilical veins is pathognomonic for portal hypertension. Paraumbilical vein dilation has been observed in about 34% of cirrhotic patients, while in groups with greater impairment of the liver function (Child C patients) this percentage may be even higher, with reported rates as high as 57%.

Portosystemic communication can lead to vascular dilation in these pathways, that may lead to a peculiar aspect in the periumbilical region often compared to Medusa’s head (origin of the latin term caput medusae).

Take Home Message

As important as detecting collateral circulation in cases of portal hypertension, as important it is to know its possible paths.

References

1. Melo-Leite AF, Mota Jr. A, Chagas-Neto FA, Teixeira SR, Elias Junior J, Muglia VF. Acquired portosystemic collaterals: anatomy and imaging. Radiol Bras.2016 Jul/Ago;49(4):251–256.
2. MARTINELLI ALC. Hipertensão portal. Medicina, Ribeirão Preto, jul./dez. 2004; 37: 253-261.
3. Machado MM, CRF Ana, Barros N, Azeredo LM, Rosa JBF, Cerro LMO, Chammas MC, Daher MT, Daher RT, Saad WA, Cerri GG. Estudo Dopper na hipertensão portal. Radiol Bras 2004; 37 (1):35-39.

Correct answer is:

Spontaneous complete detorsion of previously twisted ovary/adnexa

Explanation:

We have shown a case of spontaneous detorsion of a previously twisted ovary. Ovarian or adnexal (ovary and fallopian tube) torsion is a surgical emergency that requires prompt diagnosis and treatment. It is defined as complete or partial rotation of the adnexa around the pedicle, causing lymphatic and venous ovarian congestion, followed by ischemia and necrosis due to arterial occlusion when untreated. It can rapidly progress to a stage of hemorrhagic necrosis in a few hours or remain at the stage of edema for several days, rarely resulting in complete spontaneous detorsion.

Adnexal torsion accounts for approximately 3% of all gynecological emergencies [1]. The torsion may involve normal adnexa, however ovarian enlargement predisposes to torsion, commonly by corpus luteal cyst, benign ovarian tumour or ovulation induction [2, 3]. Prompt diagnosis is important to prevent irreversible damage of the ovary. However, the diagnosis can be challenging because clinical presentation of ovarian torsion is variable and often misleading. Definitive diagnosis is often achieved by surgery [4, 5]. Sonography is usually the first imaging tool used for evaluation, but the diagnostic accuracy is rather poor (46-74%) [6-9]. The sonographic findings vary from the enlarged ovary simulating a mass with peripherally displaced follicles in the early phase and a “solid” avascular appearance of the ovary in the late phase. However, Doppler is not a very sensitive for diagnosing ovarian torsion, and normal flow does not rule out torsion [10, 11]. An important sonographic sign of adnexal torsion is the “whirlpool sign”. A coiling pattern of ovarian vessels in the ovarian ligament refers to the sonographic appearance of the twisted ovarian vascular pedicle and has been shown to have up to 87% diagnostic accuracy for ovarian torsion [12-14]. In the rare cases of spontaneous complete detorsion the ultrasound findings can persist for a while after the untwisting because the edema does not disappear immediately [15].

In conclusion, the diagnosis of ovarian torsion remains challenging. In a patient who presents with acute pain and an ovary that demonstrates sonographic findings consistent with ovarian torsion, the diagnosis should be suggested even in the presence of documented arterial blood flow.

References

1. Rochelle F. Andreotti, Sara M. Harvey. Sonographic Evaluation of Acute Pelvic Pain. J Ultrasound Med 2012; 31:1713–1718.
2. Mashiach S, Bider D, Moran O, Goldenberg M, Ben-Rafael Z. Adnexal torsion of hyperstimulated ovaries in pregnancies after gonadotropin therapy. Arch Gynecol Obstet 2002;267(1):4 –6.
3. Purcell K, Wheeler JE. Benign disorders of the ovaries and oviducts. In: De Cerney A, Nathan L, editors. Current obstetric and gynecologic diagnosis and treatment. New York: McGraw-Hill; 2003.
4. Kokoska ER, Keller MS, Weber TR. Acute ovarian torsion in children. Am J Surg 2000; 180: 462–465.
5. Gordon JD, Hopkins KL, Brooke JR, Giudice LC. Adnexal torsion: color Doppler diagnosis and laparoscopic treatment. Fertil Steril 1994; 61: 383–385.
6. Mazouni C, Bretelle F, Ménard JP, Blanc B, Gamerre M. Diagnosis of adnexal torsion and predictive factors of adnexal necrosis. Gynecol Obstet Fertil 2005; 33:102–106.
7. Bar-On S, Mashiach R, Stockheim D, et al. Emergency laparoscopy for suspected ovarian torsion: are we too hasty to operate? Fertil Steril 2010; 93:2012–2015.
8. Reuven Mashiach, Nir Melamed, Noa Gilad, Gadi Ben-Shitrit, Israel Meizner. Sonographic Diagnosis of Ovarian Torsion. Accuracy and Predictive Factors. J Ultrasound Med 2011; 30: 1205–1210.
9. Cohen SB, Weisz B, Seidman DS, Mashiach S, Lidor AL, Goldenberg M. Accuracy of the preoperative diagnosis in 100 emergency laparoscopies performed due to acute abdomen in nonpregnant women. J Am Assoc Gynecol Laparosc 2001; 8: 92–94.
10. Hurh PJ, Meyer JS, Shaaban A. Ultrasound of a torsed ovary: characteristic gray-scale appearance despite normal arterial and venous flow on Doppler. Pediatr Radiol 2002; 32(8): 586- 8.
11. Shadinger LL, Andreotti RF, Kurian RL. Preoperative sonographic and clinical characteristics as predictors of ovarian torsion. J Ultrasound Med 2008; 27:7–13.
12. Lee EJ, Kwon HC, Joo HJ, Suh JH, Fleischer AC. Diagnosis of ovarian torsion with color Doppler sonography: depiction of twisted vascular pedicle. J Ultrasound Med 1998; 17:83–89.
13. Vijayaraghavan SB. Sonographic whirlpool sign in ovarian torsion. J Ultrasound Med 2004; 23: 1643–1649.
14. V. Valsky, E. Esh-Broder, S.M. Cohen, M. Lipschuetz and S. Yagel. Added value of the gray-scale whirlpool sign in the diagnosis of adnexal torsion. Ultrasound Obstet Gynecol 2010; 36: 630–634.
15. Ghossain MA, Hachem K, Aoun NJ, Haddad-Zebouni S, Mansour F, Suidan JS, Abboud J (2006) Spontaneous detorsion of the ovary: can it be diagnosed by MRI? J Magn Reson Imaging 24(4):880–885.

Correct answer is:

Thick and echogenic bands surrounding the portal vessels and gallbladder. – Schistosomiasis (hepatosplenic form)

Explanation:

Schistosomiasis is an important health problem in underdeveloped countries, especially in South America. The case represents a hepatosplenic form of this disease. The main findings in this presentation are thick and echogenic bands around the portal vessels and the gallbladder. Splenomegaly is highly prevalent in these patients, often with siderotic nodules. The rate of blood flow in the portal vein is usually normal (>16 cm/s) in the early stages of the disease.

In cirrhosis the main signs are nodulated liver surface, parenchymal disorganization, caudate lobe hypertrophy and portal hypertension with low blood flow speeds in the portal vein, typically <15 cm/s.^1,2,3

Take home message:

Although ultrasound findings must be associated with epidemiologic information for best accuracy, in a liver marked by periportal thickening, especially if associated with pronounced splenomegaly, schistosomiasis must be remembered in the differential diagnoses of liver diseases. Special attention must be taken to the thick and echogenic bands surrounding the portal vessels and the gallbladder.

References

1. Azevedo, LM; Queroz LC; Santo, MCCE; Chammas, MC. Aspectos ultrassonográficos e hemodinâmicos da esquitossomose mansônica: avaliação pela ultrassonografia Doppler em áreas endêmicas. Radiologia Brasileira, vol.43 nº2-Mar/Abr 2010
2. Hatz C, Jenkins JM, Ali QM, Abdel- Wahab MF, Cerri GG, Tanner M. A review of the literature on the use of ultrasonography in schistosomiasis with special reference to its use in field studies. 2. Schistosoma mansoni. Acta Trop 1992;51:15¾28CH, Dickman K, Tisch DJ. Reassessment of the cost of chronic helmintic infection: a meta-analysis of disability-related outcomes in endemic schistosomiasis. Lancet 2005; 365:1561.
3. Meurs L, Mbow M, Vereecken K, et al. Epidemiology of mixed Schistosoma mansoni and Schistosoma haematobium infections in northern Senegal. Int J Parasitol 2012; 42:305.

Explanation

Biliary atresia can be diagnosed based on biliary hilar thickening (the so called triangular cord sign), hypoplastic gallbladder, and enlarged hepatic artery – the relation between it and the right hepatic portal branch is = 0.66 (Normal < 0.50).

Except for the periportal thickening, the liver keeps its usual sonographic features. Indirect signs of liver disease as ascites and splenomegaly are the only suspicious findings on B-mode ultrasound.

Elastography, specially 2D-SWE, has an important role as it can show increased liver stiffness, usually above 20 kPa. This is due to biliary atresia as well as to liver cirrhosis that is already present at this age. The child was referred to liver transplantation.

Expected findings related to the alternative answers

Answer 1: Neonatal hepatitis – Liver has normal sonographic features. Liver stiffness can be slightly increased, around 10 to 15 kPa.

Answer 2: Obstruction due to biliary sludge – in this setting there is biliary dilation. The sludge can be seen inside the common bile duct.

Answer 3: Congenital cirrhosis – due to multiple causes, as congenital infections, metabolic disorders, gestational alloimmune liver disease, haemophagocytic lymphohistiocytosis, and ischaemic injury. If cirrhosis develops during pregnancy, the newborn shows signs of liver failure. Portal hypertension signals can be depicted by Doppler. In this setting the ductus venosus does not close, and can be seen with flow at color Doppler. Usually, the liver has no other suspicious findings

References

1. Ciocca M, Álvarez F. Neonatal acute liver failure: a diagnosis challenge. Arch Argent Pediatr. 2017;115:175-180.
2. Duan X, Peng Y, Liu W, Yang L, Zhang J. Does Supersonic Shear Wave Elastography Help Differentiate Biliary Atresia from Other Causes of Cholestatic Hepatitis in Infants Less than 90 Days Old? Compared with Grey-Scale US. Biomed Res Int. 2019;9036362.
3. Leschied JR, Dillman JR, Bilhartz J, Heider A, Smith EA, Lopez MJ. Shear wave elastography helps differentiate biliary atresia from other neonatal/infantile liver diseases. Pediatr Radiol. 2015;45:366-75.
4. Neonatal Liver Failure and Congenital Cirrhosis due to Gestational Alloimmune Liver Disease: A Case Report and Literature Review. Roos Mariano da Rocha C, Rostirola Guedes R, Kieling CO, Rossato Adami M, Cerski CT, Gonçalves Vieira SM. Case Reports in Pediatrics. 2017;7432859
5. Wang X, Qian L, Jia L, Bellah R, Wang N, Xin Y, Liu Q. Utility of Shear Wave Elastography for Differentiating Biliary Atresia From Infantile Hepatitis Syndrome. J Ultrasound Med. 2016;35:1475-9.
6. Zhou L, Shan Q, Tian W, Wang Z, Liang J, Xie X. Ultrasound for the Diagnosis of Biliary Atresia: A Meta-Analysis. AJR Am J Roentgenol. 2016;206:W73-82.
7. Zhou LY, Wang W, Shan QY, Liu BX, Zheng YL, Xu ZF, Xu M, Pan FS, Lu MD, Xie XY. Optimizing the US Diagnosis of Biliary Atresia with a Modified Triangular Cord Thickness and Gallbladder Classification. Radiology. 2015;277:181-91.

Explanation

The Northern Lights phenomenon is caused by micro bubbles bursting during B-mode scanning at a point in time after Sonazoid administration when the organ in question (here the liver) is still packed with microbubbles.

The high density of Sonazoid bubbles will cause attenuation of sound, thus initially preventing sound propagation to deeper layers. At the same time it will burst the microbubbles due to the high MI inherent with B-mode imaging (as opposed to the deliberate setting of very low MI during CEUS scanning)  thus generating a hyper-enhancing band horizontally across the image plane first superficially and later in the deeper parts.

The bursting bubbles are seen as a hyper-enhancing band propagating from the near filed towards deeper tissue layers when the most superficially placed bubbles are cleared by the first sound waves thus paving the way for the next wave – and the next and the next… and so forth still moving deeper down bursting its way through.

The artifact is well described and actually was part of the diagnostic procedure back in the early days when bubble disruption mode was part of the CEUS algorithm (1). It has been named “The gray-scale veil” to emphasize that this high MI CEUS artifact presents as a ‘Veil’ moving down into the deeper tissue parts as a veil covering underlying information (2)

References

1. Skjoldbye B, Pedersen MH, Struckmann J, Burcharth F, Larsen T. Improved detection and biopsy of solid liver lesions using pulse-inversion ultrasound scanning and contrast agent infusion. Ultrasound Med Biol 2002;28:439-444.
2. Wilson SR, Burns PN, Muradali D, Wilson JA, Lai X. Harmonic hepatic US with microbubble contrast agent: initial experience showing improved characterization of hemangioma, hepatocellular carcinoma, and metastasis. Radiology. 2000;215(1):153-61.

Ultrasound description

Ultrasound revealed a 4 mm, well circumscribed, slightly hypoechoic lesion in the right scrotum. It had a hyperechoic center and no flow on colour Doppler. The lesion did not change in size or location during Valsalva. The testis, epididymis and spermatic cord appeared normal.

Image gallery below indicates the original images without indicators, one with indicators indicating the lesion and one indicating both the lesion and adjacent anatomical structures.  (click on images to enlarge)

Discussion

The appendix epididymis is, along with the appendix testis, thought to be a vestigial remnant without vital function. While the appendix epididymis is a small, stalked structure attached to the head of the epididymis, the appendix testis is a  fixed, globular structure located at the cranial pole of the testis[1,2]. The appendages may appear unassuming, but are clinically significant, as up to 60% of cases of acute scrotum in children have been reported to arise from torsion of the appendages [3,4].

The most common ultrasound findings in the case of a torsed appendix are the presence of an enlarged, hetero- or homogenous avascular mass with hyperemia and edema of the surrounding structures  [2,3]. The condition most often requires only symptomatic treatment [3].

Discerning a relatively benign torsion of the appendages from the surgical emergency of testicular torsion by clinical examination is difficult, as symptoms often overlap. Ultrasound  is considered to be both sensitive and specific in this regard, and findings suggestive of testicular torsion include absent or reduced intra-testicular blood flow compared with the asymptomatic side, twisting of the spermatic cord and abnormal location and appearance of the epididymal head [5].

Teaching points

Torsion of the epididymal or testicular appendix is one of the most common finding in the acute scrotum in children. Ultrasound examination with colour Doppler is an important tool in ruling out the more severe diagnosis of testicular torsion.

References

1. Sahni D, Jit I, Joshi K, Sanjeev. Incidence and structure of the appendices of the testis and epididymis. J Anat. 1996 Oct;189 ( Pt 2):341–8.
2. Sellars MEK, Sidhu PS. Ultrasound appearances of the testicular appendages: Pictorial review. Vol. 13, European Radiology. 2003. p. 127–35.
3. Lev M, Ramon J, Mor Y, Jacobson JM, Soudack M. Sonographic appearances of torsion of the appendix testis and appendix epididymis in children. J Clin Ultrasound. 2015 Oct 1;43(8):485–9.
4. Kalfa N, Veyrac C, Lopez M, Lopez C, Maurel A, Kaselas C, et al. Multicenter assessment of ultrasound of the spermatic cord in children with acute scrotum. J Urol. 2007 Jan;177(1):297–301; discussion 301.
5. Alkhori NA, Barth RA. Pediatric scrotal ultrasound: review and update. Vol. 47, Pediatric Radiology. Springer Verlag; 2017. p. 1125–33.