Answer for BIR CoW 19 June 2022
DANDYWALKER MALFORMATION
FINDINGS
GROSSLY DILATED BILATERAL , THIRD, AND FOURTH VENTRICLE NOTED WITH REDUCED VOLUME OF BILATERAL CEREBRAL HEMISPHERES ENLARGED POSTERIOR FOSSA SEEN WITH VERMIAN HYPOPLASIA AND ELEVATION OF TORCULAR HEROPHIL TORCULAR LAMBDOID INVERSION NOTED TEGMENTO VERMIAN ANGLE = 51 DEGREES THINNED OUT CORPUS CALOSSUM NOTED FALX CEREBRI NOTED IMPRESSION FEATURES CONSISTENT WITH DANDY WALKER MALFORMATION
DISCUSSION
LARGE POSTERIOR FOSSA CYST EXTENDING POSTERIORLY FROM FOURTH VENTRICLE VERMIAN AGENESIS OR HYPOGENESIS INCREASED TEGMENTO VERMIAN ANGLE > 45 DEGREES TORCULAR LAMBDOID INVERSION HYDROCEPHALUS VERMIAN HYPOPLASIA OLD TERM – DANDY WALKER VARIANT REDUCED VERMIAN TISSUE BELOW FASTIGIUM – DECLIVE LINE SUPERIOR ROTATION OF VERMIS TEGMENTO VERMIAN ANGLE 18-45 DEGREE POSTERIOR FOSSA NORMAL SIZE BLAKE POUCH CYST EPENDYMA PROTRUSION FROM FOURTH VENTRICLE NORMAL VERMIS TEGMENTO VERMIAN ANGLE 18-45 DEGREE MEGA CISTERNA MAGNA RETROCEREBELLAR CSF > 10 MM NO MASS EFFECT ON VERMIS OR CEREBELLUM NORMAL VERMIS TEGMENTO VERMIAN ANGLE < 18 DEGREE FLUID CROSSED BY VEINS AND FALX CEREBELLI ARACHNOID CYST NOT TRULY DANDY WALKER CONTINUUM CEREBELLO VERMIAN ANGLE > RETRO VERMIAN NO CROSSING VEINS OR FALX CEREBELLI CAUSES MASS EFFECT
REFERENCES
ABDEL RAZEK AA ET AL : MAGNETIC RESONANCE IMAGING OF MIDBRAIN – HIND BRAIN. J COMPUT ASSIST TOMOGR. 40(1):14-25, 2016 COTES C ET AL : CONGENITAL BASIS OF POSTERIOR FOSSA ANOMALIES, NEURORADIOL J. 28(3):238-53, 2015
FINDINGS
GROSSLY DILATED BILATERAL , THIRD, AND FOURTH VENTRICLE NOTED WITH REDUCED VOLUME OF BILATERAL CEREBRAL HEMISPHERES ENLARGED POSTERIOR FOSSA SEEN WITH VERMIAN HYPOPLASIA AND ELEVATION OF TORCULAR HEROPHIL TORCULAR LAMBDOID INVERSION NOTED TEGMENTO VERMIAN ANGLE = 51 DEGREES THINNED OUT CORPUS CALOSSUM NOTED FALX CEREBRI NOTED IMPRESSION FEATURES CONSISTENT WITH DANDY WALKER MALFORMATION
DISCUSSION
LARGE POSTERIOR FOSSA CYST EXTENDING POSTERIORLY FROM FOURTH VENTRICLE VERMIAN AGENESIS OR HYPOGENESIS INCREASED TEGMENTO VERMIAN ANGLE > 45 DEGREES TORCULAR LAMBDOID INVERSION HYDROCEPHALUS VERMIAN HYPOPLASIA OLD TERM – DANDY WALKER VARIANT REDUCED VERMIAN TISSUE BELOW FASTIGIUM – DECLIVE LINE SUPERIOR ROTATION OF VERMIS TEGMENTO VERMIAN ANGLE 18-45 DEGREE POSTERIOR FOSSA NORMAL SIZE BLAKE POUCH CYST EPENDYMA PROTRUSION FROM FOURTH VENTRICLE NORMAL VERMIS TEGMENTO VERMIAN ANGLE 18-45 DEGREE MEGA CISTERNA MAGNA RETROCEREBELLAR CSF > 10 MM NO MASS EFFECT ON VERMIS OR CEREBELLUM NORMAL VERMIS TEGMENTO VERMIAN ANGLE < 18 DEGREE FLUID CROSSED BY VEINS AND FALX CEREBELLI ARACHNOID CYST NOT TRULY DANDY WALKER CONTINUUM CEREBELLO VERMIAN ANGLE > RETRO VERMIAN NO CROSSING VEINS OR FALX CEREBELLI CAUSES MASS EFFECT
REFERENCES
ABDEL RAZEK AA ET AL : MAGNETIC RESONANCE IMAGING OF MIDBRAIN – HIND BRAIN. J COMPUT ASSIST TOMOGR. 40(1):14-25, 2016 COTES C ET AL : CONGENITAL BASIS OF POSTERIOR FOSSA ANOMALIES, NEURORADIOL J. 28(3):238-53, 2015
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!