We revised CT and MRI findings in 6 patients diagnosed with PCNSL at our centre in the last 5 years.
CT and a conventional sequences-MRI were performed on all of them.
We also used more advanced techniques (spectroscopic and perfusion MRI) on 3 of them.
PET-CT was used in 3 patients to rule out systemic involvement.
In 6 the diagnosis was reached by biopsy,
and in 1 case through a specific study of the cerebroespinal fluid.
Case1: Fig. 1
We report a case of a 46-year-old male with left facial nerve paralysis,
hearing loss,
and tinnitis as first presentation.
He was successfully diagnosis by cytology as Primary central nervous system lymphoma (PCNSL) small cell variant.
MR:
- T2 and T2 FLAIR-weighted images: white matter hyperintensities with enlargement and thickening of the left trigeminal nerve.
- T1-weighted postcontrast MR: diffuse enhancement with thickening of the meninges and V,
VII,
VIII cranial nerves.
- Diffusion weighted imaging DWI b-1000-ADC: the lesions have no restricted diffusion.
Case 2: Fig. 2
We report a case of a 54-year-old male with headaches and visual disturbances.
He was diagnosed by biopsy as small B cell lymphoma.
Head CT scan withand without contrast:
- Hyperdense lesion in the recess of the third ventricle,
with marked perilesional vasogenic edema and intense enhancement pattern in postcontrast exploration.
MR:
- T1,
T2 and T2 FLAIR-weighted images: hypointense lesion with marked perilesional vasogenic edema.
- T1-weighted postcontrast MR: diffuse peripheral enhancement.
- Axial and Coronal T1 with Gd: presents intense peripheral enhancement.
- Diffusion weighted imaging DWI b1000-ADC: the lesions have restricted diffusion,
and diffusion b-1000 values weakly increased.
Case 3: Fig. 3
A 71-year-old man was brought to the mergency department by 061 as "Code Stroke".
Surgical biopsy reveals small B lymphoma.
Head CT scan withand without contrast:
- Left temporal lesion isodense with homogeneous intense enhancement pattern.
MR:
- T2 and T2 FLAIR-weighted images: isointense lesion with marked perilesional vasogenic edema.
- T1-weighted postcontrast MR: heterogeneous enhancement pattern in association with areas of necrosis.
- CT perfusion maps showed increased Cerebral Blood Flow (CBF).
- Diffusion weighted imaging DWI b1000-ADC: the lesions have no restricted diffusion.
Case 4: Fig. 4
We report a case of a 63-year-old female with visual acuity loss.
She was diagnosed by biopsy as having Primary central nervous system lymphoma (PCNSL),
large B cell variant.
Head CT scan withand without contrast:
- left cerebellar hemisphere hyperintense lesion with homogeneous enhancement pattern.
MR:
- T1 and T2 -weighted images: hypointense on T1 and isointense on T2.
- T1-weighted postcontrast MR: intense homogeneous enhancement pattern.
- CT perffusion maps showed increased Cerebral Blood Flow (CBF).
- Diffusion weighted imaging DWI b1000-ADC: the lesions have no restricted diffusion.
- Arterial spin labeling (ASL) reveals the cerebral blood flow (CBF) was weakly increased.
Case 5: Fig. 5
60-year-old woman was brought to the emergency department with right hemianopsia.
Past medical history: Stroke.
She was diagnosed by biopsy as having small B cell lymphoma.
Head CT scan withand without contrast:
- Left parietal lesion hypodense without enhancement after intravenous contrast administration.
MR:
- T1 and T2 -weighted images: the left parietal lesion was heterogeneous in signal intensity.
- T1-weighted postcontrast MR: cortical gyral enhancement pattern with necrosis and subcortical nodular enhancement.
- Magnetic resonance spectroscopy: lactate peak was markedly elevated and the choline peak was weakly increased.
- Diffusion weighted imaging DWI b1000-ADC:the lesions have restricted diffusion.
- CT perfusion maps showed decreased Cerebral Blood Flow / CBF and Cerebral Blood Volume / CBV (probably a result of necrosis).
Case 6: Fig. 6
78-year-old man was brought to the emergency department with recent onset of weakness of the right leg.
Past medical history: Waldenstrom macroglobulinemia (therapy with rituximab).
Head CT scan withand without contrast:
- Hyperdense lesions are seen in periventricular white matter with edema.
MR:
- T1 and T2 -weighted images: hypointense lesions in periventricular white matter with edema.
- T1-weighted postcontrast MR: thick periventricular enhancement pattern.
- Magnetic resonance spectroscopy: Markedly elevated the choline with reduced NAA and creatinine peaks.
- Diffusion weighted imaging DWI b1000-ADC: the lesions have restricted diffusion.
Results summary: Fig. 7
•PCNSL presented as solitary lesion (4 cases - 66%),
as multiple lesion (1 case - 16%) and as meningeal infiltration (1 case- 16%).
•5 patients with solid lesions were analyzed.
Tumor location was supratentorial in 4 patients (80%) and infratentorial in 1 patient (20%).
• In total,
5 cases had brain CT-scans.
CT scan without contrast showed a hyperdense lesion in 3 cases,
(60%) and hypodense lesion in 2 cases (40%).
All of them presented vasogenic cerebral edema.
CT scan post contrast revealed 4 lesions with an intense and homogeneous enhancement pattern,
one of them with central necrosis.
One patient had lesions with a peripheral enhancement pattern with central necrosis.
• Our patients had no intracranial hemorrhage associated.
• Two patients were evaluated using MR spectroscopy,
one case showed a classic malignant pattern and the other was unspecified.
• Four patients who had solitary lesions were studied with Diffusion weighted MRI,
the lesions had restricted diffusion in 75% and had no restricted diffusion in the other 25%.
• In total,
3 cases were evaluated using perfusion studies,
the lesions revealed an increased CBV/CBF in 2 cases (66%).
• The patient with multiple lesions was under treatment with rituximab.