The first attractive feature of PBC is the excellent immediate success rate, which was identically reported by nearly every published paper[3–6, 9–11, 13], anyway, there is some level difference about the recurrence rate between studies. Skirving reported that all but one of their 522 successful procedures to 496 patients experienced immediate pain relief. The recurrence rate was 19.2% within 5 years and 31.9% over the entire study period, with a mean follow up duration of 10.7 years. In another larger series of PBC reviewed, Benaissa reported “appreciable pain relief” in 92.7% patients one month after the procedure in their 901 patients; while pain free remained in 62%, and recurrence occurred in 27.8% of their patients with mean follow-up of 16.5 years. Anyway, in a study by Jason (A review of percutanous…), the authors concluded recurrence rate as high as 26% with a mean time of 18 months.
Our results seemed supper to those reported by others, with complete pain relief in 95.6 and partial pain relief in 1.1 percet patients immediately after the procedure; with median follow-up time of 7.2 years, complete pain relief remained in 82.9, partial pain relief in 6.8 percent patients; the pain recurrence happened in 8.5 percet patients. We believed our supper’ results may be ascribed to following reasons. Firstly, in comparison with our universal idiopathic trigeminal neuralgia patients, many studies were composed by cohort of patients with discrepancy, such as patients with non idiopathic trigeminal neuralgia symtoms, multiple sclerosis were also included, which was supposed to affect the outcomes negatively. As a example, in a series report by Tommy, the author found the median pain-free time without medication of 28 months in their 100 consecutive PBC procedure. While those 100 patients were subdivided into primary TN (n = 77) and TN secondary to multiple sclerosis (n = 23), the median pain-free times were 33 months and 24 months (P = 0.2) respectively. Secondly, we thought it is reasonable that the operator’s experience achieved from larger series have positive influence on the results. At last, it is worth noting that the satisfied balloon shape, which have been considered as golden standard for success, were achieve in 99.7% patients in our series.
In fact, we believe that the success rate might be increased in further if the patients with “delayed heal” had also been included. Here, the “delayed heal” denoted that the pain did not cease immediately after the surgery, instead, it might fade away within weeks or months. In practice, this phenomenon occurred not uncommon in our series. Our strategy toward this kind of patients was to suspend the repeated surgical procedures till at least three months in case the satisfied balloon shape and some level sense loss on the affected face, as expected, were obtained in the original procedure.
As an ablative procedure at peripheral level of trigeminal nerve, some level sense loss is understandable and is expected, which was also commonly considered as an inevitable side effects in a successful case. Our results, 95.1 percent patients experienced hypothesia immediately after the procedure, is in agreement with others. However, it worth noted, there were still 62.3% (including hypothesia in 54.3%, dysesthesia in 6% and anesthesia dolorora in 2%) patients experienced sensoryloss in different level with median follow-up 7.2 years, which is obviously differ from many of the studies, they usually believed that it will recover within 3–9 months[9, 11, 16], and we are not able to give a reasonable explanation for this situation. As a major shortcoming of the PBC procedure, troublesome dysesthesia are often addressed and the rate of 2.8%-11.4% was also reported in literature[5, 6, 10, 17, 18]. Our results, with dysesthesia in 6% and anesthesia dolorosa in 2% patients were roughly in line with results reported by others.Masseter muscle weakness is another common side effect, which has been mentioned in many reports[11, 13, 15, 19]. In a special designed study, the author concluded that the masster muscle weakness should be expected in all cases after PBC procedure, and it would usually resolve within 12 months. In our series, 90.6 percent patients experienced masster muscle weakness immediately after the procedure, while the symptom remained in 7.5 percent patients in the follow-up study.
Compared with those common side effects abovementioned, diplopia is one of the fewer complications, happened in 1.1 percent patients immediately after the procedure and usually resolved spontaneously within 3 months in our series. In a specially designed paper for studying the diplopia, the author noted six patients with diplopia postoperatively, and they found that the balloon was inflated outside Meckel’s cave in four, the balloon was initially inflated too deeply in one patient, and probably aberrance anatomy of Meckel’s cave in one patient.
Although numerous reports have established the safety of PBC in the treatment of trigeminal neuralgia, the deadly complications have been reported in some series[6, 10, 12, 22–25]. Brown and Pilitsis reported one of their patients died of diffuse subarachnoid hemorrhage from dural arteriovenous fistula in their 65 procedures performed in 56 consecutive patients over 4 years.. The other death was reported as the result of unsuccessful attempts to penetrate the foramen ovale, which led to a brainstem hematoma and subsequent death. Our result, on the whole, are broadly in line with those of the literature with three deaths occurred in our series. Two of them died of intracranial hemorrhage, and the other one died of intracranial infection.
In reviewing the literature, vascular injury complications due to PBC, such as duralarteriovenous fistula, dural arteriovenous malformations (DAVM) and CCFare rare. Unfortunately, we encountered 5 cases with vascular injury complications in our series (0.05%), and we are not able to give an exact explanation to any individual case. It is postulated that the rationale behind this rare complication may be twofold: an anatomical variation on one side and inappropriate penetration of needle or catheter on the other side.