A 9 year old female
patient presented with complaint of gradually progressive asymmetrical weakness
of all four limbs and difficulty in walking since 1 month. The patient also had
c/o difficulty in speaking and hearing since 1 month.
This was associated with c/o low grade fever since last 10 days and c/o dry cough since last 3 days.
The birth history was unremarkable.
The past history, family history and personal history were not significant.
The General Examination revealed deviation of angle of mouth to right side and drooling of saliva.
Systemic examination of Central Nervous System revealed hypertonia in bilateral lower limbs.
INVESTIGATIONS: 1) Mildy elevated WBC levels (12,900)
2)CSF Examination : Normal
3) Vitamin B-12 : Normal
MRI Brain with contrast and whole spine screening was conducted for further evaluation
Fig 1(A to D) reveal abnormal signal intensity lesion causing enlargement of bilateral thalami, appearing hypointense on T1W images (green arrows), hyperintense on T2W images (yellow arrows) and FLAIR images (red arrows); extending into mid brain (white arrows). It is causing effacement of 3rd ventricle(chevron) with mild dilatation of bilateral lateral ventricles.
The lesion involving right thalamus shows few areas of restriced diffusion on DWI (Fig 1E) with corresponding drop on ADC images (Fig 1F).
The lesion shows no focus of blooming on SWI ( Fig 1G) and no abnormal enhancement on post-contrast images (Fig 1H).
Also MRI whole spine screening was unremarkable.
MR Spectroscopy of the lesion revealed raised choline peak, depressed in N- Acetyl Aspartate peak and increased choline/creatine ratio.
DIAGNOSIS: LOW GRADE BILATERAL THALAMIC GLIOMA
IMAGING: Neuroimaging is indispensable in establishing diagnosis in affected individuals. Typically, BTGs appear as diffuse thalamic hypodensities on CT scan with no discrete enhancement. On MRI, these lesions show diffuse low signal intensity on T1-weighted images and high signal intensity on T2 / fluid attenuated inversion recovery (FLAIR)-weighted images. The tumor is usually hypo-perfused in perfusion images with no enhancement in contrast study.
Bilateral thalamic lesions are uncommon, with limited differential diagnoses that include other brain tumours (Lymphomas, teratomas, germinomas), toxic and metabolic disorders (Wernicke's encephalopathy, osmotic myelinosis), vascular conditions (infarcts, deep venous thrombosis) and infection (viral encephalitis, Creutzfeldt-Jakob disease)metabolic and toxic causes, infection, vascular lesions, and neoplasm.The diagnosis can be achieved with patient history, imaging characteristics and presence or absence of associated abnormalities outside the thalami.
In general, MR spectroscopy is not routinely performed for the evaluation of brain tumors, but it can be useful when an imaging result is equivocal. MR spectroscopy may aid the differentiation of primary brain tumors from other non-neoplastic conditions (e.g., vascular diseases, infections, and inflammatory diseases) by analyzing the chemical composition in an anatomical area of interest. The presence of decreased N-acetyl aspartate and increased choline levels are suggestive of a neoplasm.
These findings were detected on MR spectroscopy in the present case.
0 Comments