Facial nerve paralysis damages – Facial nerve paralysis is a condition which affects one side of the face and more than 75% of patients make a complete recovery. The most frequent cause to facial paralysis is due to the presence of Herpes Simplex virus in patients, this is the same virus which causes extremely annoying cold sores on the face. It is a paralysis linked to an inflammatory process and, is usually only temporary.
Other causes which may result in the development of facial paralysis are congenital causes, tumours, or trauma. Finally there are iatrogenic causes, that is, causes arising as a direct result of surgery on, the middle or the inner ear, the parotid or the base of the skull.
Paralysis due to iatrogenic causes are particularly widespread in cases where the surgery is complex and extensively involving the facial nerve, resulting in functional, aesthetic and, consequently, also psychological problems. The muscles of the face are constantly altered and this involves a number of issues related to the formulation of emotions and facial expressions. Problems of a functional nature, especially affect the eye, which often can’t be adequately lubricated, as the eyelids gradually lose their firmness. Furthermore, the patient has difficulty with speech, related to the loss of tissue tone in the cheeks and difficulty breathing due to the collapse of the medial nasal passage.
Iatrogenic causes directly linked to the appearance of facial paralysis are mainly due to cutting injuries or direct damage, to the mechanisms of tension and pressure, surgery complications such as bruising or hematoma, and poor supervision during anaesthesia. We are therefore dealing with, perioperative injury, since the onset of the condition may occur before, during or after a visit to the operating room and may be the result of an error by one of the attending: paramedics, anaesthesiologists, surgeons, etc. …
Since this condition isn’t predictable, it is difficult to estimate, even approximately, the incidences of this phenomenon. The overall risk of peripheral nerve tracts damage in patients subject to surgery is around 0.1 or 0.2%. Some of the nerves damaged in iatrogenic injuries are: the superficial radial, the spinal accessory nerve, the common peroneal nerve and the median, these split into a series of nerve branches equally involved although lesser known.
The EMG is the diagnostic tool most suited to highlighting injuries of this type and, in cooperation with conduction studies, it is possible to assess in a rather precise manner the nature of the damage, highlighting the presence of the phenomena of re-innervation of muscle, well in advance of the neurological examination on an apparent muscle contraction .
Generally facial paralysis as a result of iatrogenic factors are diagnosed promptly, allowing for immediate action, and therefore a higher percentage of success. Early intervention avoids the need for additional surgery delays and limits the amount of time the affected muscles are denervated, exponentially increasing the chances of recovery, which would otherwise be rather slim. Sometimes, however, these findings only come about after a considerable delay, beyond the optimum time for an intervention.