This instrument is described by Paul (VI. xxx) in the operation for removing the tonsils:
‘Wherefore, having seated the patient in the sunlight, and directed him to open his mouth, one assistant holds his head and another presses down the tongue with a tongue depressor. We take a hook and perforate the tonsil with it and drag it outwards as much as we can without dragging the capsule out along with it, and then we cut it off by the root with the tonsillotome (ἀγκυλοτόμον) suited to that hand, for there are two such instruments having opposite curvatures. After the excision of one we may operate on the other in the same way.’
This passage clearly proves that there were two scalpels of a set, each having opposite curvatures after the manner of our right and left vesicovaginal fistula knives.
Curved blade cutting on one side, blunt-pointed.—Fistula Knife.
Greek, συριγγοτόμον, from σῦριγξ, ‘a fistula.’
This was a falciform blade whose end was blunt, but the handle end was prolonged into a slender, rounded sound-like portion with a sharp point ([Pl. IX, fig. 1]). The narrow point was passed into a fistula, caught, and the whole instrument pulled outwards by means of it, thus dividing the overlying tissues with the falciform blade. This instrument remained in use till comparatively recent times. Heister figures a large number of varieties, and from him I have taken the figure shown, although it is also described and figured by Fabricius. The two following passages, taken in conjunction with each other, show that the classical instrument was of the form I have indicated. The first passage, from Galen, shows that the end of the blade was blunt, and that there was only one cutting side. The second, from Paul, shows that the blade was falciform and was operated in the manner I have stated. Galen (x. 415) says that in enlarging an abdominal wound we use a fistula knife (συριγγοτόμῳ). ‘But the scalpels which are two-edged or have a point are distinctly to be avoided’ (τὰ δ' ἀμφήκη τῶν μαχαιρίων ἢ κατὰ τὸ πέρας ὀξέα παντὶ τρόπῳ φευκτέα).
Secondly, Paul (VI. lxxviii) says:
‘Having perforated the bottom of the fistula with the point of the falciform part of the syringotome (τοῦ δρεπάνου τοῦ συριγγοτόμου) bring the instrument out of the anus and so divide all the intervening space with the edge of the falciform part’ (τῇ ἀκμῇ τοῦ δρεπάνου).
Another passage in the same chapter indicates that some of the syringotomes had an eye in the instrument:
Τινὲς δὲ ἐν τῷ τρήματι τοῦ συριγγιακοῦ δρεπάνου τὸ λίνον ἐνείραντες.