A total of 100 patients with tic douloureux were followed up following surgery in two series; in one, the extradural approach was used and the trigeminus sensory root was manipulated in its dural sleeve, while in the other, the trigeminus sensory root was manipulated in the dura. The intradural approach, which caused less postoperative sensory impairment in 100 patients, injured the semilunar ganglion less, and caused more complete relief in 62% of the cases. The patients, however, experienced mild recurrences in 11.5% and severe recurrences in 26.5% of the cases.
A degree of sensory loss had been reported in 26% of those with successful treatment, as well as in 28.3% of those with ineffective treatment. Neither surgical trauma to the nerve root nor incision of the nerve root’s dural sleeve was necessary to ensure success. Neurolysis or manipulation of the sensory root at the point where it crosses the apex of the pars petrosa of the temporal bone appeared to be the key part of the operation.
Many experts believe the cause of this condition is segmental demyelination of the trigeminal sensory nerve in the nerve root or brain stem, accompanied by chronic compression of the nerve root.
Multiple sclerosis is also a link. The incidence of multiple sclerosis is approximately 4 per 100,000 of the population, and only gets worse with age. The average age of onset is 60, with few diagnosed before age 40.
Clinical hygienists at chairside treating patients with TN need to understand more about this, as the triggers can have a profound impact on treatment. It has been described as an electric lightning bolt of intense pain to yawn, speak, chew, brush one’s teeth, and simply touch one’s face. Imagine the extraoral fulcrum you might use during instrumentation. Even the lightest feather-like finger rest could prove disastrous to TN patients. The painful sensation is usually unilateral, lasts several seconds to several minutes, and can occur a few times a day or hundreds of times a day.
Remission can occur, but the intervals between relapses tend to shorten as the patient ages. TN is diagnosed based only on history, after hearing the patient’s description of the pain. It is believed that the condition can lead to depression since daily life activities can be impaired. Experts find that symptoms worsen over time and become less responsive to medication, despite dosage increases and other agents being added.
When it comes to treatment success for TN, standard definitions vary depending on whether it is medical or surgical. If at least half of pain relief compared to baseline readings is achieved with medication, it is considered successful. However, with surgical studies, measurements are different. Complete pain relief is the goal, so this would be considered treatment success.