Diagnosis Please : May 3rd, 2016

56yr old male with right eye proptosis of 10yr duration.

DIAGNOSIS ???

Diagnosis Please : May 2nd, 2016

What could be probable diagnosis in this elderly patient?

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Frontal lobe abscess : follow up MRI

Patient 2 months back, presented with headache and fever. CT and MRI done were consistent with the clinical diagnosis of Brain Abscess in the frontal lobe, which measures ~5.1cm x 4.6cm x 3.1cm (~37mL as per 0.52 x ABC). Abscess was aspirated at that time.

Present MRI showed T2 hyperintense lesion with hypointense rim / capsule. Perilesional vasogenic oedema was seen in frontal-parietal and temporal white matter.

Lesion is showing a T1 iso to mildly hyperintense rim. 

SWI images showed peripheral blooming artefacts of the lesion, which are seen tracking towards the calvarium - indicating the possibility of post aspiration haemorrhage.

Track is also seen showing susceptibility artefacts.

The entire contents of the abscess cavity is showing restricted diffusion.

Smooth rim enhancement of the lesion in post contrast images are noted. 

The track is also noted enhancing. Surrounding parenchyma also showed intense enhancement. No other lesions were seen. No CVT / Oto-mastoiditis seen. Lesion in the current study measured only about ~8mL. 

Right Partial Hemifacial Hyperplasia

Cervical spine MRI was done for a young male patient, for evaluation of neck pain. Incidentally there was right hemifacial hyperplasia, which was noticed by the patient since childhood.

Right masseter showed increased thickness ( Compare with the left).

Right IJV is seen enlarged.

Right parotid gland is also seen enlarged.

Depending on involvement of soft tissues, teeth, and bones, Rowe further classified hemifacial hypertrophy into (a) true hemifacial hypertrophy and (b) partial hemifacial hypertrophy.

True hemifacial hypertrophy exhibits unilateral enlargement of all tissues, teeth, bones, and soft tissues, characterized by viscerocranial enlargement, bounded by frontal bone superiorly (sparing the eye), inferior border of the mandible inferiorly, midline medially, and ear including the pinna laterally.

In partial hemifacial hypertrophy not all structures are enlarged to the same degree or limited to one structure. The term hyperplasia is more precise histologically, as all tissues show an increase in the number of cells rather than an increase in cell size.

Hemifacial hyperplasia is associated with a wide variety of abnormalities such as thickened skin and hair on the involved side, excessive secretion of sebaceous and sweat glands, and vascular and pigmentary defects of the affected side. Different texture and colour variance of ipsilateral scalp hair have also been reported. In addition skeletal abnormalities such as macrodactyly, polydactyly, syndactyly, ectrodactyly, scoliosis, tilting of pelvis, and clubfoot have also been described.

Central nervous system involvement in the form of cerebral enlargement, epilepsy, strabismus, and mental retardation in 15–20% of patients has been reported in the literature. Ipsilateral pinna and pupil may be enlarged, but an increase in size of the inner ear or globe of the eye has not been reported. Occurrence of small exostoses of the posterior auditory canal has also been reported.

Adrenal cortical carcinoma, nephroblastoma (Wilm’s tumour), and hepatoblastoma can be occasionally associated with this disorder. Genitourinary system disorders, such as hypospadias, cryptorchidism, and medullary sponge kidney, were also noted occasionally.

Other bony conditions that may result in hemifacial enlargement like FD, Paget's etc are usually associated with narrowing of the skull base foramina, but hemifacial hyperplasia usually result in their widening.

References
R. A. Pollock, M. Haskell Newman, A. R. Burdi, and D. P. Condit, “Congenital hemifacial hyperplasia: an embryologic hypothesis and case report,” Cleft Palate Journal, vol. 22, no. 3, pp. 173–184, 1985.

N. H. Rowe, “Hemifacial hypertrophy—review of the literature and addition of four cases,” Oral Surgery, Oral Medicine, Oral Pathology, vol. 15, no. 5, pp. 572–587, 1962.

Bansari A. Bhuta, Archana Yadav, Rajiv S. Desai, Shivani P. Bansal, Vipul V. Chemburkar, and Prashant V. Dev, “Clinical and Imaging Findings of True Hemifacial Hyperplasia,” Case Reports in Dentistry, vol. 2013, Article ID 152528, 7 pages, 2013. doi:10.1155/2013/152528

Hypoxic-Ischemic Brain Injury in a post cardiac arrest patient

Middle age patient, referred from outside hospital, was brought to the emergency due to a cardiac arrest, and was resuscitated successfully. Patient GCS score was low on the following days. MRI Brain was done later to r/o any hypoxic-ischemic insult to the brain.

 

Diffusion-Weighted MR image showed hyper intensity involving the bilateral precentral gyri and frontal eye-fields bilaterally.

Restricted diffusion was also seen in the bilateral parieto-occipital areas, in a relatively symmetrical manner.

T2 FLAIR and T2 FSE images showed symmetrical hyper intensity of the bilateral lentiform and caudate nuclei, but with no restricted diffusion.

Corresponding ADC mapping images showed hypo intensity consistent with restricted diffusion.

In SWI images no abnormal blooming artefacts were seen in the brain lesions.

Grade 3 ( Trans-Sphincteric) Perianal Fistula

Coronal STIR image showing a fistulous track, in the right peri-anal region. External opening is in the right perianal region, with track coursing inferiorly. Track is seen traversing along the outer aspect of the external anal sphincter on right side.

Superiorly the track is seen entering through the external anal sphincter.

Axial STIR images demonstrating the fistula coursing through the external anal sphincter.

The internal opening of the fistula was seen in the posterior midline (6'o clock) position.


According to the St.James University Hospital Classification this is classified as a Grade 3 Or Trans-sphincteric fistula. There was no abscess formation of secondary tracking into the ischio-rectal fossa. No supralevator extension was seen.

Hypertrophic Pachymeningitis

T1 pre and post-contrast axial images showing meningeal thickening with abnormal enhancement in the left parietal convexity.

Similar type of pachymeningeal enhancement is also seen in bilateral parieto-occipital convexities also.

(T1 MPRAGE Post  Contrast Sagittal Image)

(T1 MPRAGE Post  Contrast Sagittal Image)

This young female patient had presented with history of multiple cranial nerve palsies, including few episodes of visual blurring, with symptoms over past few months. No abnormal enhancement of the basal dura were seen during this scan. Scan was performed to rule out any demyelinating diseases like MS.

The brain parenchyma showed no abnormal T2 FLAIR hyper intensities. Screening of the whole spine with T2 Sagittal images showed no cord hyper intensities or swelling.

There were no evidence of Intracranial Hypotension ( like tonsillar herniation, rounded adenohypophysis, distended venous sinuses, sagging of corpus callous or brainstem). Patient is not a known cancer patient.


Differential  Diagnosis of Hypertrophic Pachymeningitis

1.Infection / Inflammation
   Sarcoidosis : Usually have other lesions. Difficult to differentiate.
   TB : More common is leptomeningeal involvement.
   Wegener's Granulomatosis : Recurrent sinus disease. Lung or Kidney pathologies.
   RA, SLE, Sjogren's : Have systemic symptoms.
   Inflammatory Pseudotumor
2. Intracranial Hypotension : Usually have other associated features as mentioned above.
3. Tumors like en plaque meningioma, lymphoma, metastases. (Lymphoma usually have associated systemic component). En plaque meningioma may have associated bone erosion or hyperostosis, and a long non-neoplastic dural tail.
4. Dural sinus occlusion : Engorged collaterals will be seen. Empty delta sign.
5. Chronic SDH : Usually have some SWI/GRE blooming artifacts and T1/T2 signal abnormalities.
6. Normal dural enhancement.

Hypertrophic pachymeningitis can be caused by a plethora of conditions. Will need meningeal biopsy correlation for a specific diagnosis.

Adenomyosis of Uterus

ADENOMYOSIS of the UTERUS

Adenomyosis is the presence of ectopic endometrial glands and stroma embedded within the myometrium. Morphologically adenomyosis is classified into two : Focal and Diffuse. Clinicians and pathologist distinguishes between Superficial and Deep adenomysosis.

Adenomyotic endometrial glands do not typically undergo cyclical bleeding. In cases where there is extensive hemorrhages within the ectopic endometrial tissue, results in cystic adenomyosis.

Adenomyosis is a relatively common gynecologic disorder, with incidences up to 20% to 60%, seen in reproductive and perimenopausal ages. Common symptoms include dysmenorrhoea and menorrhagia.

DIAGNOSIS by MRI relies mainly on the T2 Weighted Images which depict the zonal anatomy. Thickened junctional zone >12mm is usually considered as diagnostic of Adenomyosis.

(T2 Sagittal Image showing thickened junctional zone, measuring up to 14.2mm, T1 hyperintense focus secondary to hemorrhage)

Ancilliary findings include Poorly defined margins, High signal intensity focus on T1 and T2 images and Linear high signal striations radiating from endometrial surface.

In some cases there may be T1 hyperintense foci which corresponds to the areas of hemorrhage within the ectopic endometrial tissue (see image above).

References
1. Clinical MRI - Edelman.

Diagnosis please !!

For answer and discussion of the diagnosis click the following link

ANSWER

BENIGN VERTEBRAL COLLAPSE

Case history :  Elderly female with back pain of 1 week duration.

Discussion : Benign Vs Malignant Vertebral Collapse.

Fatty filum terminale

 

LIPOMA OF FILUM TERMINALE

Persistence of caudal cells that differentiate toward fat could produce filar lipomas. The presence of fat within the filum terminal may be observed incidentally in 4% to 19% of normal adults and may be considered a normal variation if the fat is not associated with cord tethering or neurologic dysfunction.

Typically, fatty fila thicker than 2 mm are regarded as filar lipomas.They exhibit increased signal intensity on T1-weighted images and progressively lower signal intensity with greater T2 weighting and are easily observed on good sagittal and axial sections.
(Ref : Scott Atlas, 4th, 2009).

This is sometimes also called as fibrolipoma of filum terminale. Conus medullaris has to be normal in position.     (Ref : Differential Diagnosis in MRI, Burgener).

Choroid Fissure Cyst

 9 year old male child for follow-up scan of an incidentally detected right temporal lobe cyst.

Choroid fissure cyst is a benign intracranial cyst, which is a location based diagnosis, rather than a histological one. Cysts can be an arachnoid cyst or a neuro-epithelial cyst. The cyst shows signal characteristics that resemble CSF in all sequences. No enhancement on contrast is seen. There will no surrounding hyperintensity.

The choroidal fissure is the CSF space between the fimbria of hippocampus and the diencephalon. This is normally a shallow fissure that curves posterosuperiorly from the anterior temporal lobe to the atrium of lateral ventricle. Tela choroidea is a double layer of pia mater that invaginated through the choroid fissure to reach the lateral ventricles.

Ref : MRI of CSF-like Choroidal fissure and parenchymal cysts of brain, AJNR 1990.

Arachnoid cyst of Septum Pellucidum

5 year old male child presented with complaints of ?seizures.
MRI Brain were within normal limits excepting the cystic enlargement of the septum pellucidum.

 

Arachnoid cysts account for ~1% of all intracranial masses.

On imaging, they are characterized as well circumscribed cysts, with an imperceptible wall, displacing adjacent structures, and following the CSF pattern (hypodense on CT and hyperintense on T2 with FLAIR suppression on MRI).


References
1. Radiopaedia.org
2. Arachnoid cyst of septum pellucidum  

Periventricular Leukomalcia Vs Normal PV Blush

Periventricular Leukomalcia Vs Normal Periventricular Blush
- Normally the periventricular area can be slightly echogenic.

- Early PVL appears as periventricular increased echogenicity ( PV area- Watershed area in premature babies and Posterior Parieto-Occipital areas are watershed areas in Term Infants).


To differentiate remember this --
"Echogenicity that is less echogenic than the adjacent choroid plexus is considered   to be normal.Coarse, echogenic areas equal to or greater than that of the adjacent choroid are suspicious for PVL. When in doubt, scanning through the posterior fontanelle will eliminate the normal periventricular blush, whereas the pathological echogenicity of PVL will persist."