A comparative study of the pterygopalatine fossa and its ganglion in a South African skeletal and cadaver population

Abstract

Blocking the contents of the pterygopalatine fossa (PPF) is a highly effective method in alleviating pain in trigeminal neuralgia (TN) and other facial pain syndromes. This, however, is not a widely used technique, due to the difficulty in locating the PPF which is obscured by bony and soft tissue structures. Despite the various unspecific techniques that have been attempted, in many cases radiography still seems to be used as it is the most effective method in locating the PPF. The aim of this study was therefore to achieve a safe and alternative method of locating the PPF including its contents without the aid of radiography. A total of 160 skulls from the Pretoria Bone Collection at the University of Pretoria were used. Distinct anatomical landmarks and the use of existing and new anthropometric measurements were used to define the location of the PPF in any individual. Regression analysis provided the strength of influence each measurement had on the location of the PPF. From the results, two mathematical formulae were devised (one for each side). These formulae were tested on 47 cadavers by substituting the measurements of each individual into the created formulas. A needle was then inserted at the calculated points, and the area around the needle dissected to determine whether or not it was in the PPF. Our results showed an accuracy of 65.22% on the right and 54.35% on the left. It is hoped that this new technique will aid researchers and clinicians alike in the management of various pain disorders as well as pain management during surgery. AFRIKAANS : Daar is bevind dat ‘n lokale verdowingsblok van die inhoud van die pterygopalatine fossa (PPF) die pyn effektief verlig vir trigeminale senuweepyn, sowel as ander pyn sindrome. Die tegniek word egter nie gereeld gebruik nie as gevolg daarvan dat dit moeilik is om die PPF te betree deurdat dit deur verskeie benige en sagte weefsels verberg word. Die literatuur beskryf verskeie onspesifieke metodes om die prosedure uit te voer, maar in die meeste gevalle moes radiografie gebruik word om sukses te behaal. Die doel van hierdie projek was om ’n alternatiewe metode te ontwikkel wat veilige en effektiewe toegang tot die PPF bied, sonder om radiografie te gebruik. ’n Totaal van 160 skedels was gebruik om anatomies landmerke en bestaande sowel as nuwe antropologiese metings te maak. Regresie analise het die sterkte van die invloed van die onderskeie metings met die pterygopalatine fossa gemeet. Vanuit die resultate van die statistiese analise is twee formules ontwerp (een vir elke kant van die gesig). Die formules was getoets op 47 kadavers deur die metings vir elke individu in die formules te plaas. ‘n Naald is dan geplaas in die uitgewerkte punt, die area om die naald was gedisekteer om te sien of die naald in die fossa en dus by die ganglion was of nie. Die resultate toon ‘n akkuraatheid van 65.22% aan die regterkant en 54.35% aan die linkerkant. Daar word gehoop dat hierdie nuwe tegniek ‘n effektiewe manier van pyn behandeling word in verskeie pyn sindrome sowel as gedurende chirurgie vir beide navorsers en chirurge.