Visual Diagnosis by Betsy Helander

This is a parasternal long axis view of a 21 year old female who recently underwent surgery for correction of tetralogy of fallot.

To obtain the parasternal long axis cardiac view, the probe should be placed near the sternum around the T4 interspace with the marker positioned towards the apex of the heart. This is a three chamber view in which you should visualize the left ventricle, the left atrium and the right ventricle. As you fan into view you should also be able to see the aortic outflow tract as well as the descending thoracic aorta.

In this image you see a moderate sized pericardial effusion which wraps around the anterior and posterior portion of the heart. You can distinguish this from anterior cardiac fat by noting the presence of the fluid posteriorly as well. Near the top of the image, which is anterior, you see the right ventricle. There is notable right ventricular hypertrophy evidenced by the thickened muscular wall. Also significant in this picture is the ventricular septum which does not display a smooth, congruent contour. This patient recently underwent a ventricular sepal defect repair which was not completely closed and with color flow you would see a small ventricular septal defect remaining.

Videos:
Pericardial 1

Pericardial 2

Case by Rachel Metz

A 22 yo female who is 10 weeks 5/7 days pregnant by LMP presents to the ED with vaginal spotting and intermittent RLQ abdominal pain for the past month. She notes that the pain is crampy at times and is worse when walking. The patient also notes that she has had similar pain with all of her three previous pregnancies. She denies nausea or vomiting but notes some constipation. Her vital signs were stable. She is afebrile and her abdomen is soft non-distended but tender in the RLQ. There is no rebound or guarding. Vaginal exam shows an os that is open to fingertip and scant amount of blood in the vaginal vault. The ultrasound is shown below.

Trans



Long

When ultrasounding someone who is pregnant it is best to start with the trans abdominal approach. This view is best done when the patient has a full bladder. This was the approach used in the above patient. The patient was known to be pregnant but upon ultra sounding it was found that the patient had a twin pregnancy with two chorions/placentas (dichorionic) and two amniotic sacs (diamniotic).
The common misconception when ultra sounding is that the presence of two sacs diagnoses a twin pregnancy as fraternal twins. The diagram below shows the different ways identical twins can present

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While Mono chorionic twins are almost always identical, same sexed dichorionic twins can be dizygotic or monozygotic. If two distinct placentas are found then the pregnancy is always dichorionic. However if a single placenta is seen the pregnancy may be mono chorionic or it can represent a fused placenta and be dichorionic. The lambda sign or peak twin sign helps to differentiate the type of twin pregnancy and is seen in dichorionic/diamniotic pregnancy. It is seen as a triangular projection that extends between two layers of amniotic membrane as shown by the arrows in the picture below.

Clinical course of patient

The patient had an ultrasound of her RLQ and later an MRI to rule out appendicitis. The patient was seen by Ob/Gyn and was diagnosed with constipation and round ligament pain. The patient returned two more times after this visit for the same pain over the next 4 weeks.


References:
1.Noble, Vicki E. “Emergency and Critical Care Ultrasound”
2. sonoguide.com
3. Sperkly, Lene; Taylor, Ann. “ Twin pregnancy: the role of ultrasound in management” Acta Obstetricia et Gynecolgia Scandinavia. Vol 80, Iss 4 15, jan 2002
4. Woo, Jean; Tonge, Stephen “ Corpus Lutea seen at 6-13 weeks gestation infers dizygosity amoung spontaneous same sexed dichorionic twins” Twin research and human genetics. Volume 12 Num 2 pp 180-182
5. worldtttsawarenessday.org “ lambda sign picture”
6. obmd.com for monozygotic twin picture.

Case by Myles McClelland



Image #1: Hypoechoic hypervascular testis consistent with orchitis. Also present is a hydrocele, a fluid collection surrounding the testicle, commonly seen with orchitis.




Image #2: Hypervasculature in epididymitis. The pyramid-shaped epididymis is seen superior to the testis. It is enlarged, edematous, hypoechoic, and hypervascular with Doppler flow.

Discussion: The testicle can be evaluated by placing the high frequency probe initially in the longitudinal position along the testicle. The sonographer should scan through the entire testicle looking for areas of hypervascularity and heterogenicity, and use color flow Doppler to evaluate for adequate blood flow and hypervascularity. The probe should then be rotated 90 degrees in the transverse position scanning through the superior and inferior poles. Both testicles should be evaluated for comparison. Special care should be taken to evaluate the entirety of both testicles and identifying extra testicular structure including scrotal skin thickness, epididymis, rete testi, spermatic cord, and vasculature. A normal testicle will appear homogeneous with an echo texture similar to the thyroid gland. Due to the encapsulation by the tunica vaginalis the normal testis will appear to have a hypoechoic ring.


In patients with epididymo-orchitis, ultrasound will demonstrate an enlarged and heterogeneous epididymis with diffusely hypoechogenic and hypervascular testis. Although it is not demonstrated in the following images it is also common to find scrotal skin thickening.