Rare clinical presentations of perineural cysts besides radicular pain.

LETTER TO EDITOR

The recent article by Jung et al. [1] was highly interesting. However, I tend to have a different view with that of the authors in that perineural cysts (PCs) are rarely symptomatic. In fact, PCs may present in a number of ways.

For instance, some patients may present with radicular pain such as L5 radiculopathies [2]. Similarly, "persistent genital arousal disorder" may occur in females secondary to sacral PCs [3]. Patients with PCs may also present with symptoms of interstitial cystitis [4]. Similarly, perianal pain may be one of the presentations of PCs [5]. They may also present as adnexal masses that upon further evaluation are revealed as PCs [6]. Infertility and retrograde ejaculations may also occur secondary to the compressive symptoms of PCs [7]. Sacral PCs may also result in sacral fractures [8].

Similarly, "moving toes syndrome" has been reported in some patients with PCs [9]. Some patients may present with "cubital tunnel syndrome" [10]. Some patients may also present with symptoms of "piriformis syndrome" [11]. PCs may rarely be bilateral and cause bilateral peripheral neuropathy [12] and may seldom occur in multiple members of the same family which points towards a possible congenital etiology of these cysts.

Rupture of a PC may rarely cause complications such as emboli. For instance, cerebral fat emboli have been reported following the rupture of a PC [13]. Rupture may also result in spontaneous intracranial hypotension [14].

The above examples clearly illustrate that PCs may present in a myriad of ways. Physicians should always keep PCs on their differential when dealing with the above mentioned symptoms.