Answer for BIR CoW 01 Sep 2024
Fungal cerebral abscess
Findings
Evidence of relatively well-defined T2 hyperintense lesion and surrounding T1 hyperintense, T2 hypointense rim having crenated margin with surrounding oedema causing effacement of ipsilateral frontal horn of body of lateral ventricle with mild subfalcine herniation. The lesion shows central diffusion restriction with low ADC values and rim of gradient blooming noted in right high frontal region. The lesion measures 2.5(anteroposterior) x1.5(transverse) x2 (cranio caudal )cm. Impression well-defined T2 hyperintense lesion with T1 hyperintense, T2 hypointense rim having crenated margins with mass effect and central diffusion restriction with rim of gradient blooming in right high frontal parasagittal region
Discussion
Most CNS fungal infections are opportunistic, resulting from inhalation of fungal spores and pulmonary infection followed by hematogeneous dissemination Disseminated fungal disease usually occurs only in immunocompromised patients CT –fungal abscess ○ Hypodense center ○ Hyperdense rim ○ Variable hemorrhage (angioinvasive infections) MRI Hypointense center, hyperintense rim on T1WI ○ Hyperintense center, hypointense rim on T2WI ○ Hemorrhagic "blooming" foci on T2* common ○ Restriction on DWI ○ Strong enhancement on T1 C+ MRS lactate in 90%, lipids and amino acids in 50%; multiple peaks at 3.6-3.8 ppm Differential Diagnosis • Pyogenic abscess ,Tubercular abscess, • Neoplasm (primary, metastatic) PYOGENIC ABSCESS Morphology- solitary involving grey and white matter junction wall-smooth T1 W-hypointense T2 W- hyperintense T1 C-smooth rim enhancemen ADC-shows diffusion restriction MRS-aminoacids(0.9),acetate(1.9 ppm),succinate(2.4ppm) Rim-hypointense on T2,hyperintense on T1 SWI- dual rim sign-outer hypointense,inner –hyperintense rim relative to abscess core TUBERCULAR ABSCESS Morphology-single or multipe often multilobulated Wall-smooth,lobulated and crenated T1 w-hypointense T2 w- non caseated-hyperintense caseated-hypointense T1 c-rim enhancement more often lobulated ADC-shows diffusion restriction MRS-lipid(1.3ppm) +lactate (1.3ppm) hyperintense on T1 Rim-hypointense on T2 FUNGAL ABSCESS wall-irregular wall with intracavitory projection T1 W-hypointense T2 W -hypointense T1 W-peripheral enhancement with no enhancement of projection ADC-wall and intracavitory projection low on adc,cavity itself shows high on ADC MRS-)lipid,lactate,aminoacids,peak between 3.6-3.8 ppm assaigned to trehalose Rim-hyperintense on T1,hypointense on T2
Findings
Evidence of relatively well-defined T2 hyperintense lesion and surrounding T1 hyperintense, T2 hypointense rim having crenated margin with surrounding oedema causing effacement of ipsilateral frontal horn of body of lateral ventricle with mild subfalcine herniation. The lesion shows central diffusion restriction with low ADC values and rim of gradient blooming noted in right high frontal region. The lesion measures 2.5(anteroposterior) x1.5(transverse) x2 (cranio caudal )cm. Impression well-defined T2 hyperintense lesion with T1 hyperintense, T2 hypointense rim having crenated margins with mass effect and central diffusion restriction with rim of gradient blooming in right high frontal parasagittal region
Discussion
Most CNS fungal infections are opportunistic, resulting from inhalation of fungal spores and pulmonary infection followed by hematogeneous dissemination Disseminated fungal disease usually occurs only in immunocompromised patients CT –fungal abscess ○ Hypodense center ○ Hyperdense rim ○ Variable hemorrhage (angioinvasive infections) MRI Hypointense center, hyperintense rim on T1WI ○ Hyperintense center, hypointense rim on T2WI ○ Hemorrhagic "blooming" foci on T2* common ○ Restriction on DWI ○ Strong enhancement on T1 C+ MRS lactate in 90%, lipids and amino acids in 50%; multiple peaks at 3.6-3.8 ppm Differential Diagnosis • Pyogenic abscess ,Tubercular abscess, • Neoplasm (primary, metastatic) PYOGENIC ABSCESS Morphology- solitary involving grey and white matter junction wall-smooth T1 W-hypointense T2 W- hyperintense T1 C-smooth rim enhancemen ADC-shows diffusion restriction MRS-aminoacids(0.9),acetate(1.9 ppm),succinate(2.4ppm) Rim-hypointense on T2,hyperintense on T1 SWI- dual rim sign-outer hypointense,inner –hyperintense rim relative to abscess core TUBERCULAR ABSCESS Morphology-single or multipe often multilobulated Wall-smooth,lobulated and crenated T1 w-hypointense T2 w- non caseated-hyperintense caseated-hypointense T1 c-rim enhancement more often lobulated ADC-shows diffusion restriction MRS-lipid(1.3ppm) +lactate (1.3ppm) hyperintense on T1 Rim-hypointense on T2 FUNGAL ABSCESS wall-irregular wall with intracavitory projection T1 W-hypointense T2 W -hypointense T1 W-peripheral enhancement with no enhancement of projection ADC-wall and intracavitory projection low on adc,cavity itself shows high on ADC MRS-)lipid,lactate,aminoacids,peak between 3.6-3.8 ppm assaigned to trehalose Rim-hyperintense on T1,hypointense on T2
Note:
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!
We do not discourage differential diagnosis. But all the differentials must satisfy the findings noted in the case.
If you feel you have answered rightly but cannot find your name in the above list, please call 09551942599.
Did you Know?
The order in which the names appear in this winner's list is based on the time of submission. The first person to send the correct answer gets his/her name on top of the list!