Spot Diagnosis

Spot Diagnosis

What is "Spot Diagnosis" all about! That's a tough one! I really don't have a straight answer. It is supposed to showcase the work we do at Jankharia Imaging, but the website anyway does that job, so that's not really it. I guess its just that we have so much material, that it would a waste for all that stuff to be lying only in our archives. I have taken the challenge of publishing daily, one case a day, and currently we have seven threads running on a weekly basis (Head Injuries Lecture, CT Urography, etc). From August though, we will be publishing five times a week only, keeping Saturday and Sunday, in ours and your lives, for non-radiology stuff.

I also want to see how long I can keep this up, but honestly I don't see any reason for it not to go on and on and on......

Radiology Grand Rounds - VI

It is my turn to host the Radiology Grand Rounds that Sumer has so well popularized. Unfortunately, I have not been able to keep up with this blog itself, but nevertheless, here we go.

At Filmjacket.com, if all you did was look at these images of portal venous gas, and extreme hydrocephalus, you would think that you were walking into a "House of Horrors". Or qualify for a "Wall of the Weird" entry, with this old post from Medgadget. Since images form the core of radiology, let's wish Radiology Picture of the Day all the best as it attempts to put up one new case every day. Quizzes keep our minds sharp and these two have been going on and on and on for many, many years. Check out the weekly quizzes at Radiology Education Foundation and Korean Thoracic Society.

Off track weird topics have been carried by Sumer as well, when he talks about x-ray vision and Superman. And I thought this post about drinking barium, so that it shields the fetus from the ill-effects of radiation during pregnancy, was a joke as well, until I checked out its source. Sumer has flirted with contrast media issues this month, discussing new data on complications with gadolinium. Surprisingly, there is now data on skin damage with gadolinium, as well.

Technology is our backbone. But stupid things like this can happen, as Dalai realized, when internet-security nerds become ultra-conservative. And as the world moves ahead, marketing has become an issue to be looked at seriously and if done ethically, there is no reason, why it should not be something that we use to enhance our work. And as the world changes, issues like teleradiology bring up their own problems and raise tempers.

As we move out of the reading rooms into the real world, some columnists like Scanman and Michael Brand-Zawadski, should never be ignored.

Happy reading.

Radiology Ground Round Archives

MDCT for assessing pancreatico-biliary union

This article, by Itoh S et al , in the September issue of the AJR, shows how MDCT (using 4-slice) can depict the pancreatico-biliary ductal anatomy exceptionally well. This allows the diagnosis of the abnormal channel, especially in patients with choledochal cysts.

Because of the superior spatial resolution with multi-slice scanners, it is highly likely that the results with MSCT for this particular purpose, will be better than MRCP.

We have had a similar experience on our 64-slice CT. This is a child with a choledochal cyst (Fig. 1), where the abnormal pancreatico-biliary channel is extremely well seen (Figs. 2, 3).

Giant cell tumors - dynamic curves

This patient has a typical giant cell tumor in the lower end of the radius on the plain radiograph (Fig. 1). The T1W coronal (Fig. 2) and T2W sagittal (Fig. 3) images, show typical features. On the contrast enhanced study, the lesion shows homogeneous enhancement (Fig. 4). The dynamic study however shows that the lesion is vascular with rapid uptake and wash-out, paralleling the artery (Fig. 5).

This is a curve usually seen with malignant tumors, but also seen in the vast majority of virgin and especially recurrent tumors.

Solitary pulmonary nodule lecture - slides 7-11

Cervical vertebra biopsy

This 24-yeras old student had neck pain. An MRI revealed a C4 vertebral lesion. A contrast-enhanced CT scan prior to the biopsy showed an expansile osteolytic lesion involving the body and pedicle (Figs. 1, 2) with abnormal soft tissue. Under CT guidance, a core biopsy was performed, both of the soft tissue as well as from within the lesion (Figs. 3, 4).

Adequate tissue was obtained, which was reported to be tuberculosis.

Subependymal heterotopia

This is a 12-years old girl, previously asymptomatic, with a history of fever followed by three episodes of seizures.

The MRI images (Figs. 1-3) show a smooth, nodular area, isointense to grey matter, on all pulse sequences, along the margin of the atrium of the right lateral ventricle. The closest differential diagnosis is a hamartoma of tuberous sclerosis, but this would be irregular with its long axis perpendicular to the ventricular wall and will not be isointense to grey matter.

MRI arthrography of the hip in femoro-acetabular impingement (FAI)

This is an article by Pfirrmann et al from Zurich, describing the differences in the Cam and Pincer types of femoro-acetabular impingement (FAI) in the September issue of Radiology.

In Cam type of FAI, there are abnormal labral changes along the anterior and antero-superior aspects with an abnormal alpha angle due to non-sphericity and an abnormal osseous bump at the head-neck junction. In the Pincer type of FAI, there are abnormal labral changes postero-inferiorly, with over-riding of the anterior acetabulum or an increased acetabular depth.

The article nicely mentions these differences and findings and describes the various related issues.

This patient with a Cam type FAI shows acetabular ossicles on the plain radiograph (Fig. 1), which is otherwise normal. The MRI arthrogram shows an antero-superior labral tear (Figs. 2, 4 - red arrows). An osseous bump is noted at the head-neck junction on the oblique axial image (Fig. 3).

Giant cell tumor - distal radius

This 25-years old lady showed an expansile, osteolytic, trabeculated lesion involving the epiphysis and metaphysis of the distal end of the radius, with a narrow zone of transition, the lesion extending upto the articular surface (Figs. 1, 2). There appeared to an anterior cortical break (Fig. 2). The MRI showed the lesion to be isointense on the T1W images (Fig. 3) and mildly hyperintense on the T2W images (Fig. 4) with a focal area of necrosis (red arrowhead). The anterior cortical break (red arrow) and extra-osseous extension of the soft tissue, was well appreciated on the T2W sagittal image (Fig. 4).

Solitary pulmonary nodule lecture - slides 4-6

Radiofrequency ablation (RFA) of a lung tumor

This is a 78-years old man, who had a 3.8cm sized mass in the left upper lobe (Fig. 1), which was proven to be a squamous cell carcinoma. There was marked surrounding emphysema and though the lesion was a T1 lesion, with no adenopathy or evidence of spread elsewhere on a PET study, he was not considered to be a candidate for surgery.

He was referred for a radiofrequency ablation (RFA). We had to make sure that we did not penetrate the emphysematous lung. Using the CT fluoroscopy function, it was possible to find an oblique route into the centre of the lesion (Figs. 2-4) and the tines of the electrode were then deployed (Figs. 5,6). A successful ablation was obtained with peri-lesional ground-glass attenuation (Fig. 7).

There was no evidence of a pneumothorax, but a plain-radiograph (FIg. 8) obtained 24 hours later showed fluid-fluid levels, presumably due to hemorrhage into the bullae. The patient however was comfortable and was discharged with due precautions.

Neuroradiology case of the week

Every Friday, we will be putting up a new Neuroradiology case

1. Neuronal ceroid lipofuscinosis

Neuronal ceroid lipofuscinosis (NCL)

This is a 5-years old boy, normal at birth with regression of social and language milestons in the last few months with loss of vision, due to retinitis pigmentosa.

An MRI was performed, which shows moderate cerebral and cerebellar atrophy with a reduction in the volume of the cerebral white matter (Figs. 1, 2). The T2W images demonstrate confluent hyperintense signal in the periventricular zones along the margins of the lateral ventricles and optic radiations extending into the lateral geniculate bodies (Figs. 3-5). Ill-defined T2 hyperintense signals are noted in the deep white matter. Short TE spectra (Fig. 6) suggestive of increase in myoinositol and glutamine-glutamate at 3.56 and 3.6-3.8 ppm are seen. Choline/creatine ratios are relatively well preserved. The NAA/creatine ratios are slightly decreased. Long TE spectra (FIg. 7)  do not show significant lactate peak.

In the given clinical setting, these findings are suggestive of neuronal ceroid lipofuscinosis.


 

High-resolution MRI lymphangiography

A new technical innovation from Germany, by Lohrmann C et al, in the August issue of the AJR, shows how we can perform high-resolution MRI lymphangiography using gadodiamide (Omniscan), by injecting it into the web-spaces of the toes and imaging approximately 45-60 minutes later. The lymphatic vessels are very well seen and patients with lymphedema can thus be imaged.

Considering that traditional lymphangiography is so difficult nowadays to perform, especially due to the lack of availability of Lipiodol, this should be an attactive technique to use.

Giant cell tumor

This is a 20-years old lady whose knee radiograph shows a well-defined, expansile osteolytic lesion involving the epiphysis and metaphysis of the lower end of the femur, extending upto the articular surface, with subtle trabeculations. The zone of transition is narrow, as would be expected in benign lesions.

This appearance is highly suggestive of a giant cell tumor.

Solitary pulmonary nodule lecture

1. Slides 1-3

2. Slides 4-6