A study spanning 16 years of data and thousands of cases of acoustic neuroma surgery outcomes across the country found that facilities where the relatively rare treatment is performed at higher volumes resulted in better outcomes and shorter hospital stays.
Vestibular schwannoma, otherwise known as acoustic neuroma, involves a usually slow-growing tumor that develops within the inner ear. Schwannoma refers to Schwann cells, which normally wrap around nerve fibers to help support and insulate them, including hearing and balance nerves inside the ear.
Overproduction of Schwann cells in the form of a tumor, however, can cause hearing loss, tinnitus (ringing in the ear), dizziness and loss of balance. If untreated, a growing tumor can interfere with the trigeminal nerve, which controls facial sensations, such as touch and temperature, and helps you chew. If the tumor becomes large enough, it can press against nearby brain structures and become life threatening.
Treatment may involve stereotactic radiosurgery, which delivers precisely targeted radiation to the tumor while avoiding surrounding healthy tissue, but surgery is often the preferred option.
In a cohort study published online March 2, 2023 in JAMA Otolaryngology, physicians-scientists at UC San Diego School of Medicine report that higher vestibular schwannoma surgical volumes were associated with a reduced risk of adverse outcomes, shorter hospital stays and less likelihood of subsequent readmission.
Study authors reviewed 11,524 relevant cases at U.S. medical facilities accredited by the Commission on Cancer between 2004 and 2019. The median case volume was 16 cases per year, but with higher case volume, authors said reports of adverse reactions and excess hospital times declined, plateauing around 25 cases per year. Surgery at facilities with annual case volume at or above 25 were associated with a 42% reduction in the odds of excess time compared to those below the 25-case-per-year threshold.
For patients with vestibular schwannoma and facing surgery — there are an estimated 3,000 new cases diagnosed annually — the data may provide food for thought when choosing a place for surgery, wrote the authors.
“These findings suggest that higher hospital surgical volume may be associated with reduced risk of excess time in the hospital after vestibular schwannoma surgery, and 25 cases per year may represent a risk-defining threshold.”
Vestibular schwannomas are relative rare. They are not commonly seen or treated. Since 2017, UC San Diego Health has operated a special clinic that focuses on acoustic neuromas. You can read more here. The clinic, notably, performs twice as many acoustic neuroma surgeries as the next highest program in the country.
– Scott LaFee