{Reference Type}: Case Reports {Title}: Sigmoid sinus diverticulum without pulsatile tinnitus occurring concurrently with chronic otitis media mucosal type. {Author}: Kuotsu R;Mallick A;Roy M;Mukherjee A; {Journal}: BMJ Case Rep {Volume}: 17 {Issue}: 7 {Year}: 2024 Jul 3 暂无{DOI}: 10.1136/bcr-2023-259052 {Abstract}: Sigmoid sinus diverticulum is a rare vascular anomaly often associated with pulsatile tinnitus. It can occur in cases of chronic otitis media squamous type (unsafe type) due to dehiscence of the sigmoid sinus plate caused by cholesteatoma. The presentation of which is that of pulsatile tinnitus. However, we present an unusual case of sigmoid sinus diverticulum occurring concurrently with chronic otitis media mucosal type (safe type) but in the absence of pulsatile tinnitus. This case report highlights the diagnostic challenges and management of this rare clinical scenario.