Expanding Virchow Robin space in the midbrain causing hydrocephalus

Findings

Figure 1: Noncontrast CT brain image demonstrate a cluster of round cyst-like lesions in the right thalamic region with associated dilated 3rd and frontal horns of the lateral ventricles. Note the cyst-like lesions follow CSF attenuation. No evidence of calcification is seen.
Figure 2, Figure 3, Figure 4: Sagittal T1 weighted non-contrast images and axial T2 weighted images demonstrate a cluster of round cyst-like lesions in the midbrain/right thalamic region with associated aqueductal compression and hydrocephalus. The cyst-like lesions follow CSF signal intensity on all pulse sequences.
Figure 5: Coronal FLAIR images demonstrate a cluster of round cyst-like lesions in the midbrain/right thalamic region with associated aqueductal compression and hydrocephalus. The cyst-like lesions follow CSF signal intensity and attenuate completely on FLAIR images.
Figure 6: Coronal T1 weighted postcontrast image demonstrates a cluster of round cyst-like lesions in the midbrain/right thalamic region with associated aqueductal compression and hydrocephalus. The cyst-like lesions follow CSF signal intensity on all pulse sequences. No calcification or enhancement is seen.


Diagnosis: Expanding Virchow Robin space in the midbrain causing hydrocephalus


Pestalozzi and later Virchow in 1851 and Robin in 1859 characterized the perivascular space of Virchow-Robin. This is a pial-lined interstitial fluid – filled structure that accompanies penetrating arteries but does not communicate directly with the subarachnoid space. They affect 25-30% of the pediatric population. Mean age of occurance of enlarged PVSs in adults is mid 4th decade with a slight male preponderance. They occur at all locations and at all ages and are usually discovered incidentally. They occasionally present with non-specific symptoms such as headaches.

Normal PVSs are commonly seen in the basal ganglia region whereas giant or tumefactive PVSs are seen in the midbrain. Other common locations include deep white matter, subinsular cortex and extreme capsule. Less common sites include the thalami, dentate nuclei, corpus callosum and cingulate gyrus. They almost never involve the cortex. PVSs are usually 5mms or less. Occasionally they may enlarge up to several cms and may cause focal mass effect or obstructive hydrocephalus.

Imaging findings include clusters of round /ovoid/linear/punctuate cyst-like lesions which follow CSF density/signal intensity on all pulse sequences. They suppress completely on FLAIR images and show no restricted diffusion on DWI. They neither calcify nor enhance.

Differential diagnosis includes cystic neoplasm, lacunar infarct and infectious (neurocysticercosis, hydatid cyst) or inflammatory cysts. Enlarging PVSs are "DO NOT TOUCH" lesions unless they cause obstructive hydrocephalus where the patient needs to be shunted.

Tuberculosis-The Mimic

This is 31 yr old female who presented acute complaints, inhomogenously enhancing pathology was seen in the cerebllar vermis and a MRI diagnosis of neoplastic etiology was made. Patient underwent surgery and histopathologically turned out to be tubercular infection. Yet another reminder to the fact that TB can mimic any pathology, should be included in differential in endemic areas.

Dr.Sumer K Sethi, MD
Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers
Editor-in-chief, The Internet Journal of Radiology
Director, DAMS (Delhi Academy of Medical Sciences)

Ventriculitis-MRI

These are post Gd MRI images of an infant showing intense ependymal enhancement and hydrocephalus consistent with ventricultis. Abscess formation is also noted in the left frontal and right temporo-parietal region. Abscess is seen as differential bright signal on DWI.

Case by --

Teleradiology Providers

Right Sided Aortic Arch

These are usually asymptomatic Unless they cause encircling vascular ring like pulmonary sling etc.

Escolta: Then and Now

During the olden days, Escolta was the shopping capital of the rich and the privileged Filipinos. Going back in time during the early 20th century, a casual tourist in Manila will find in Escolta all the luxurious bazaars: Heacock's, La Estrella del Norte, Oceanic, and Beck's, to name a few. They are all gone now, replaced by more modern edifices, now occupied mostly by banks and fast food stores. Yet Escolta still exist, only its past splendor is gone.



It was also in the Escolta where the first Ice Cream parlor was established(Clarke's Ice Cream), the first cinema house was founded (Cinematografo), and the very first electric cable car was installed (the Trambiya). It was indeed the classic old Manila of cobblestones and beautiful promenades.



Yesterday, I was browsing through my collection of century old photographs, and I came across some very old pictures of the Escolta from the early years of the American occupation. The photos look old and worn, black and white and sepia, all a distant witness to a time that will never come back.



Looking at the old Escolta pictures below can evoke nostalgic memories of the yesteryears when life in Manila was simpler and gay, when everything seemed to happen one moment at a time. The pictures became a virtual time machine, enabling us to visit the old Escolta as if it were just here and now. I will probably never know who shot these pictures. But they served well the nostalgic soul inside me.



Today, I walked in Escolta to shoot some pictures of Escolta to replicate the photos taken 100 years earlier , and maybe 100 years from now, a youthful visitor to this blog will find my pictures of old Escolta comparable to the old ones I admire now.

Escolta circa 1900s (anonymous photographer)

1930s (anonymous photographer)

Early 1940s(anonymous photographer). I just noticed that street parking was already in practice during this time. The increase in car population was probably unexpected by then building owners, who did not provide parking lots for their clients. Indeed, there were no leveled parking lots in Manila during the American occupation. The streets therefore became the temporary stations of parked vehicles. After the war, the car industry boomed, and the numerous automobiles created the first traffic jams in the Philippines.



Meanwhile, here are my photographs of the present-day Escolta:





This is the view from the Sta.Cruz Church. The old Regina bulilding still stands up to this day, a vestige of the old times gone by.





The Escolta viewed from the opposite direction. Note the Sta. Cruz Church belfry on the background.





Old Shoeshine station that still exist up to this day in Escolta





Escolta street sign

New Website for Information on Hydatid Cyst Sonography

Here is a new information website by Dr Elfortia (President - Meditrranean & African Society of Ultrasound (MASU)President - Libyan Society of Ultrasound in Medicine & Biology (LSUMB).Misurata Teaching Hospital, Department of Radiology) and Dr Sumer Sethi (Consultant Radiologist, Vimhans, CEO-Teleradiology Providers www.teleradproviders.com Blog - Sumer's Radiology Site http://sumerdoc.blogspot.com Editor-in-chief,The Internet Journal of Radiology, Director DAMS (Delhi Academy of Medical Sciences) www.damsdelhi.com for latest updates on the radiology of hydatid cyst. Hydatid Cyst

http://hydatidcyst.info

All readers are welcome to send their experiences on Radiology of hydatid cyst and they will be included on the website with due credit to them.

Graves disease

Findings

0.1 mCi of I-123 in the form of sodium iodide capsule was administered orally. 4 and 24 hour radioiodine uptakes were determined. The following day, 5.4 mCi of Tc 99m sodium pertechnetate was injected intravenously for the perfusion part of the scan followed by routine planar and pinhole imaging of the neck.

There is increased flow to the thyroid gland bilaterally. Planar and pinhole imaging of the neck demonstrate a symmetrically enlarged gland with homogenous radiotracer uptake. Thyroid to salivary gland ratio is increased and there is suppression of the background. Four-hour radioactive iodine uptake (RAIU) is 22.2% and 24-hour radioactive iodine uptake is 55.3%.



Diagnosis: Graves disease


Graves disease is the most common etiology of thyrotoxicosis and predominantly occurs in middle-age females. Binding of immunoglobulins to TSH receptors results in autonomous, inappropriate hyperfunctioning of the thyroid gland. This result in suppression of TSH levels, which are typically less than 0.01 mU/L.

Thyroid scintigraphy and RAIU determination are useful for distinguishing Graves disease from other causes of thyrotoxicosis in ambiguous cases. Thyroid scan radiotracers include Tc99m pertechnetate, I123 and I131. I123 is preferred over I131 for most applications due to the shorter half-life and lower peak energy of the I123 gamma photon, which results in more optimal image quality and lower radiation dose to the patient. Imaging is performed 2-6 hours after I123 is administered. Radioiodine distributes to the salivary glands, stomach and choroid plexus and is only stored within the thyroid. The classic thyroid scan findings associated with Graves disease include homogeneously increased activity in an enlarged thyroid gland, increased thyroid to salivary gland activity and suppression of the background. RAIU measurements can be performed at 4-6 hours and 24 hours. Graves disease usually yields RAIU values of 40 to 80% (normal 10 to 30%) at 24 hours. However, high-turn over varieties may manifest only as elevated 4-6 hour RAIU values (normal 4 to 15%), as 24 hour RAIU results may be normal or only mildly elevated.

Patients with Graves disease are initially treated with beta-blockers and temporarily with thyroid specific medications, such as PTU and methimazole. Radioiodine therapy, rather than surgery, represents the definitive treatment of choice. Indeed, high cure rates result from I131 treatment doses of at least 15 mCi. Side-effects for Graves treatment doses include hypothyroidism, radiation induced thyroiditis, xerostomia, sialadenitis, change in taste, and worsening of ophthalmopathy. Leukemia and other secondary malignancies are rare in any setting and not relevant to the Graves/hyperthyroid treatment doses

Early Stroke-CT finding

NCCT done on the day reveals obscuration of the outline of lentiform nucleus, which is a early sign of infarction. CT repeated next day confirms the right MCA territiry infarct.

Anoxic/hypoxic brain injury

During initial triage, the patient had cardiac arrest and resuscitation







Five days later







Findings

No significant abnormality is noted on the first non-contrast CT head performed the day of the patient’s cardiac arrest. On the CT head performed five days later, however, there has been interval diffuse loss of gray-white differentiation, decreasing ventricular size, and decreasing sulcal prominence. In addition, at level/window shown, there is now subtle hypodensity of the caudate heads and lentiform nuclei bilaterally.

Differential diagnosis:
- Anoxia/hypoxia
- Toxic exposure
- Metabolic abnormalities


Diagnosis: Anoxic/hypoxic brain injury


Key points

A period of global intracranial hypoxia (hypoperfusion or hypoxemia) tends to affect the most metabolically active areas of the brain preferentially.
These areas include the caudate nuclei, lentiform nuclei, parahippocampal gyri, hippocampi, cerebellar hemispheres, and cerebral white matter.
A similar distribution of injury occurs with exposure to certain toxins like carbon monoxide, methanol, hydrogen sulfide, barbiturates, and Ecstasy.
Metabolic abnormalities like hypoglycemia can also cause injury to these structures and should be included in the differential.
CT findings include hypo densities in the affected areas representing edema, which later resolves leaving residual volume loss with possible calcification and/or hemorrhage.
Evidence of diffuse brain edema (loss of gray-white definition, sulcal effacement, effacement of cisterns, downward herniation, etc.) may be present acutely as well.
MR findings include increased signal on fluid sensitive sequences in the affected areas. Hemorrhagic necrosis (petechial or laminar) may subsequently develop.

Cryptococcal Meningitis-MRI

Cryptococcal organisms spread from the basal cisterns through the Virchow-Robin spaces to the basal ganglia, internal capsule, thalamus, and brainstem.The production of voluminous mucoid material may enlarge the perivascular spaces. MRI is more sensitive than CT scanning in demonstrating abnormalities such as dilated perivascular spaces. These manifest on T2-weighted MRIs as punctate, hyperintense, round or oval lesions that are usually smaller than 3 mm. This is 40 yr old man with altered sensorium clinically suspected meningitis. Cyptococcal infection was suggested and confirmed microbiologically.

Dr.Sumer K Sethi, MD

Sr Consultant Radiologist ,VIMHANS and CEO-Teleradiology Providers

Editor-in-chief, The Internet Journal of Radiology

Director, DAMS (Delhi Academy of Medical Sciences)

MR-PET Imaging is feasible

In a paper by Heinz-Peter W. Schlemmer et al in Radiology 2008;248:1028-1035 authors concluded " MR/PET data enabled accurate coregistration of morphologic and multifunctional information. Simultaneous MR/PET imaging is feasible in humans, opening up new possibilities for the emerging field of molecular imaging. "

Looks like hybrid imaging is going to feel like science fiction soon.

Hyperdense MCA sign-Hyperacute Stroke

Axial CT images demonstrate increased linear attenuation within the left middle cerebral artery. Hyperacute stroke was suspected. MRI was done and diffusion weighted MRI confirms left MCA territory infarct.

Tuber cinereum hamartoma

Findings

There is a 1 cm circumscribed, exophytic mass extending from the hypothalamus in the region of the tuber cinereum. It is isointense to gray matter on both T1 and T2 sequences. There is no appreciable contrast enhancement.

Differential diagnosis:
- Tuber cinereum hamartoma
- Non-enhancing (low grade) glioma
- Craniopharyngioma
- Germinoma


Diagnosis: Tuber cinereum hamartoma


Key points

Tuber cinereum hamartoma is a non-neoplastic focus of heterotopic gray matter.
Clinically, patients present with precocious puberty (due to increase leutinizing hormone releasing hormone release) and/or gelastic seizure activity.
Of pathologically proven lesions, 75% of patients will have experienced precocious puberty and 25% will have experienced seizures.
In patients with precocious puberty, 33% will be found to have tuber cinereum hamartoma.
Imaging features include small size (1 cm), round shape, non-enhancing, location near tuber cinereum (between pons/mamillary bodies and posterior aspect of the optic chiasm), iso- to hypo-intense on T1 sequences, and iso- to slightly hyper-intense to gray matter on T2. These tumors DO NOT invade adjacent structures.

Carotid Stenosis-MRA

These are MRA images showing significant atherosclerotic narrowing of the left proximal internal carotid artery.

A Divisoria Scenery

A Divisoria street scenery on a rush hour. The traffic was heavy, and pedestrians and vendors are everywhere. To be trapped in crowded Divisoria is truly one of the nightmares of city driving.
To avoid falling asleep behind the wheels, I took the opportunity to capture a typical scenery with my camera. Afterwards, at home, I transposed the photo into a retro digital art using Photoshop CS2, and here's the result (click to enlarge):




Below is the unedited photo (with a little tweak in contrast and saturation). I used my new dslr camera here, the Sony Alpha 100, and a 75-300 telephoto lens.

Outsourcing Radiology Services

"The internet, affordable high performance computers, the wide adoption of digital imaging, and picture archiving and communication systems (PACS) have propelled radiology into the digital era. Amy Davis has discussed pros and cons of the radiology services outsourcing in this article in BMJ, taking on issues like diagnostic clarity and cost effectiveness."

Read the full article here-

BMJ 2008;337:a785

Eagle syndrome

Findings

Figure 1 : AP radiograph of the cervical spine demonstrates an asymmetric ossified structure extending from the left side of the skull base.
Figure 2 and Figure 3 : Axial CT image and a 3D reconstruction demonstrate an elongated left styloid process that extends to the level of the vallecula as can be seen in Eagle syndrome.


Diagnosis: Eagle syndrome


An elongated styloid process, as well as calcification of the stylohyoid ligament, can result in clinical symptoms, known as Eagle syndrome. In an adult, the normal length of the styloid process is 2.5 cm. It is considered elongated when 3 cm or greater. The etiology of this rare disorder is unknown. It tends to occur at an older age, and is more common in women. Although approximately 4% of the population is thought to have an elongated styloid process, only 4 – 10.3% of this group experience symptoms. Hence, an elongated styloid process may go unnoticed, unless it results in clinical symptoms. These symptoms may occur due to irritation of adjacent nerves, most commonly the glossopharyngeal, lower branch of the trigeminal, and chorda tympani nerves. Patients may experience throat or ear pain, taste disturbance or throat discomfort. Alternatively, symptoms may arise from local mass effect, such as dysphagia or a foreign body sensation.

The differential diagnosis for Eagle syndrome is vast, largely due to the varying types of symptoms that patients may experience. However, other entities to consider include migraines, neoplasms, temporal arteritis, laryngopharyngeal dysesthesia, Sluder syndrome, cluster type headaches, glossopharyngeal/trigeminal neuralgia, temporomandibular arthritis, hyoid bursitis and cervical vertebral arthritis. Imaging will distinguish between these entities and Eagle syndrome.

Diagnosis of Eagle syndrome involves both clinical and radiological means. On physical examination, a mass may be palpated in the tonsillar fossa. A lateral plain film of the cervical spine will reveal an asymmetric elongated and ossified styloid process. A CT scan is often obtained to help clarify the relationship between the styloid process and adjacent structures of the neck. Imaging may also reveal a calcified stylohyoid ligament. A barium study performed for dysphagia may show a filling defect due to the indentation caused by the elongated styloid process.

Treatment of Eagle syndrome is both medical and surgical. In patients with mild or moderate symptoms, treatments with NSAIDs or steroid injections may be adequate. Surgical intervention is used in patients with severe symptoms and involves surgical removal of the elongated portion of the styloid process. One of the most common complications with surgical removal is infection of the deep spaces of the neck, reduced via an extraoral approach.