I thought this might be interesting and answer a couple of questions regarding the timespan of AN's
Raydean
first description? AN was first described in the latter part of the 1700's (it would be interesting to learn whether DaVinci or other early anatomists had experience with AN or other brain tumors in their work; the fact of AN being reported in the 1700's might argue against the conjecture that AN is caused by cell phones or other modern devices)
understanding the tumor: by the mid-1800's, neurologists understood that patients with unilateral (on one side only) deafness, facial numbness, and progressive blindness due to "optic neuritis" (papilledema) had a tumor of the cerebellopontine angle
diagnosis in the 1800's: in the mid-1800's, the only intracranial tumors which could be reliably identified and located were those that involved either the motor strip or cranial nerves at the base of the brain
contributions to surgery knowledge: ANs played a major role in the early development of neurological surgery since they were readily diagnosable with signs and symptoms alone
first surgery? the earliest attempt at removal of an AN apparently was performed by Charles McBurney of New York in 1891, after whom the appendectomy incision is named; the ancient Incas and some other peoples attempted brain surgery and some of their patients survived (as evidenced by bone healing); however, it is not known to this writer whether any of the wounds from Incan surgery would be consistent with an effort to relieve symptoms of acoustic neuroma; are there ancient links in non-Western medicine? e-mail us at acoustic.neuroma@attbi.com
results of first surgery in 1891: doctors reported that after opening the suboccipital plate with a mallet and gouge, the cerebellum swelled massively, so much so that it became necessary "to shave off the excess"; no tumor was removed and the patient expired twelve days later
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the first "successful" results: 1894 by Ballance in London and Annandale in Scotland; a unilateral suboccipital craniotomy was employed; complete removal was performed by finger dissection; hemostasis was obtained by packing the CPA with gauze, and there was great emphasis upon operative speed; really poor outcomes
1913 report: at the International Congress of Medicine in London in 1913 the results of Victor Horsley (London), von Eiselsberg (Vienna), and Fedor Krause (Berlin) were presented; in 63 patients, surgical mortality was 78% and most of the survivors were severely crippled (all of the early cases were those of patients who were approaching death and surgery was a last ditch effort to save them)
hydrocephalus (abnormal build up of fluids on the brain, which can cause mental deterioration, convulsions, etc.): virtually universal in AN surgical candidates into the 1930's and frequent until the CT and MRI era; much less common now (maybe several percent by some studies and it should be noted that this consequence can occur with radiosurgery as well)
the era of Harvey Cushing (Yale and Harvard): in 1905, he advocated decompression of the posterior fossa by extensive removal of suboccipital bone; he reasoned that few tumors could be safely removed and that bony decompression alone might be beneficial; after this proved fruitless, he developed a technique of subtotal tumor debulking via a bilateral suboccipital craniectomy; Cushing's greatest contributions were that he was gentle with tissues, meticulous with hemostasis, and operated deliberately without undue emphasis upon speed; he made a number of valuable innovations and advances; his mortality was 20% in 1917 but this dropped to only 4% in 1931; since he practiced subtotal removal with other advances, his mortality rate went down -- but the recurrence rate was such that many of the patients who survived surgery later died of the recurrences; this basic issue remains a consideration in today's treatment: do you use a protocol with less risk now but greater chance of recurrence and other problems later?
the era of Walter Dandy of Johns Hopkins (he studied under Cushing): in 1916 Dandy reported a case in which he totally removed an AN; Cushing, who vehemently maintained that attempts at total removal were "foolhardy in the extreme" was infuriated; later reports from 1922-1941 described a unilateral suboccipital approach during which, following gutting of the tumor, Dandy gently drew the capsule away from the brainstem; Dandy's mortality rate (about 10%) was higher than Cushing's), but this was because he sought total tumor removal (and many of Cushing's patients died later of recurrence)
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first suboccipital: 1905, M. Bourchadt performed the first combined suboccipital - transtemporal approach where he chiseled away the temporal bone to the level of the internal auditory canal to expose the tumor
the first purely translabyrinthine approach: first proposed by two writers in the early 1900's; (doctors performed cadaver dissections in which they determined the shortest route to the CPA (cerebellopontine angle, where AN's are located) was about 1-2 cm behind the ear); first performed by F. H. Quix of Utrecht in 1911; first operation aborted due to bleeding; it was completed four days later; the operation consisted of radical mastoidectomy followed by chiseling away the inner ear, including the facial nerve, to the level of the carotid artery; although the patient survived the operation, he succumbed six months later -- and on post-mortem examination only a tiny amount of tumor had been removed
translabyrinthine approach fades from view: due to problems with inadequate exposure, hemorrhage from the surrounding venous sinuses, cerebrospinal fluid leak, and meningitis the procedure was not pursued much right after 1911 and Cushing dismissed it in 1917 in an important academic work; others echoed this sentiment through 1925 and onward
the era of William House and the translabyrinthine approach: this approach perfected by House in the early 1960's; since the approach had been pushed into obscurity, it might safe to say House recreated and not just perfected the approach; by this time, more advanced equipment (surgical drills and operating microscopes) were available
facial nerve preservation: one might think that in the early decades facial nerve preservation could not happen, but it was actually first achieved in 1931 by Sir Hugh Cairns of London; there is a difference between anatomical preservation of nerves (they are there, intact, and look fine) and functional preservation (all of the preceding plus they still work)
what about cranial nerve monitoring? surely this is a modern advance; true, modern surgical techniques for nerve monitoring have advanced greatly, but the first cranial nerve monitoring was by Fedor Krause of Berlin in 1898 when he identified the facial nerve "by faradic stimulation" ("faradic" comes from the name Faraday, an electrical pioneer; "faradic stimulation" means basically inducing a current through the nerve) during an eighth nerve section for tinnitus
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facial nerve monitoring: Olivecrona of Stockholm, during the late 1930's and 1940's, was first to place great emphasis on facial nerve preservation; he too used electrical stimulation and had a nurse to observe the face during the operation; by 1940, he reported a 65% success rate in anatomical preservation of the nerve, but only 4% early function
tumor in the auditory canal: the presence of tumor within the internal auditory canal (IAC) was first recognized in 1910 by Folke Henschen, a Swedish pathologist; but surgeons did not address this until the 1950's; neither Cushing nor Dandy removed this portion of the tumor; most surgeons, even at the mid-twentieth century, truncated the tumor at the porus acusticus and coagulated the remnant; now it is recognized that the removal of the tumor from the IAC is essential
modern microsurgery: nerve monitoring of the facial nerve and the hearing nerve (if there is hope of any hearing preservation) is what patients expect today; while there are no guarantees, mortality is low and for small and medium size tumors in the hands of the best surgeons facial nerve preservation (both anatomically and functionally) is extremely likely through use of several different surgical approaches; mortality is extremely low, probably well under 1% and perhaps 0.1% or less with the best microsurgical teams
Also see our information in stories and microsurgery resource information for more information on current microsurgical information.
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See the UCSF site on AN
For more information on the above plus lots of other facts, see the University of California at San Francisco website on the history of AN surgery at:
http://itsa.ucsf.edu/~rkj/Chapter/History.html.
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