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Spontaneous return of function after surgical excision of the seventh cranial nerve in parotid tumor surgery
Spontaneous Return of Function after Surgical Excision of the Seventh Cranial Nerve in Parotid Tumor Surgery M. Hakaml, MD, Isfahan, Iran S. H. Mosavy, MD, Isfahan, Iran
Although relatively rare, it is not impossible for either partial or complete function of the seventh cranial nerve to return after surgical section or excision of this nerve. In this communication we report a case with a review of the English literature. Case Report A forty-three year old male with a ten year history of enlarged parotid gland, was admitted to Soraya Medical Center in January 1964. The parotid gland was as large as an orange, lobulated, hard in consistency, and attached to the deep tissues of the neck. The lymph nodes of the left submandibular area and the left lateral aspect of the neck were enlarged. At operation, frozen section examination revealed malignant neoplastic cells of the parotid gland. On exposure, the main trunk of the facial nerve was completely encompassed by the tumor and we had to sacrifice it. Approximately 2.5 to 3 cm of the nerve and a portion of its distal plexus were resected along with the tumor, followed by a radical neck dissection. Obviously, immediate and complete postoperative paralysis of the corresponding facial musculature ensued. The patient was discharged after a convalescent period of ten days. At one of his follow-up visits two months later, no sign of recurrence of the tumor was evident, but he was still suffering from facial paralysis. We did not see him again until December 1967 when he came to announce that his facial paralysis had improved. Surprisingly there was active movement in all parts of the once paralyzed facial musculature, including a definite wrinkling of the left forehead so that he could raise the eyebrow normally. He could also whistle and show his teeth. He was last observed on January 19, 1974, at which time he was a normal man and confident in his social contacts.
Comments
Spontaneous recovery of the facial movements after sacrifice of the facial nerve has been observed not infrequently, but it has been ascribed to some
From the Department of Surgery, lsfahan University School of Madiona, Isfahan, Iran Reprlnt requests should be addressed to M. Hakamt. MD, Department of Surgery, lsfahan Unwerslty School of Medicine, Isfahan, Iran
394
form of neurorrhaphy. Conley [1,2] in 1955 reported the fact that facial movement had returned to the face after radical extirpation of the parotid gland and facial nerve, without his resorting to rehabilitation of the face. Martin and Helsper [3] speculated that in 28 per cent of the cases studied, the fifth cranial nerve became a functional substitute for the facial nerve. They stated that new motor pathways will be established through the fifth cranial nerve and outlined these pathways as follows: (1) A communication between the auriculotemporal branch of the fifth cranial nerve and the branches of the seventh cranial nerve. (2) A communication between the infratrochlear branch of the ophthalmic nerve (fifth cranial nerve) and the zygomatic branches of the seventh cranial nerve. (3) A communication between the zygomaticofacial branches of the maxillary nerve (fifth cranial nerve) and the zygomaticofacial branches of the seventh cranial nerve. (4) A communication between the zygomaticotemporal branches of the maxillary nerve and the temporal branches of the seventh cranial nerve. (5) A communication between the infraorbital branch of the maxillary nerve and the zygomatic branches of the seventh cranial nerve. (6) A communication between the masticator branch of the mandibular nerve (fifth cranial nerve) and the plexus of the seventh cranial nerve. Conley [4] in 1964 concluded the existence of a secondary or aberrant neuromuscular facility to the mimetic muscles of the face. He stated that this facility is not functional in all patients and the system is independent of the main trunk of the facialnerve peripheral to the geniculate ganglion. Antia, Divekar, and Dastur [5] demonstrated at operative explorations that the facial nerve does not consist of a simple system of branches but rather a network or plexus of branching and reanastomosing fibers. Trojaborg and Siemssen [6] recently stated that reinnervation through the pathways other than the facial motor nerve fibers-via
the semilunar
ganglion
of the fifth
The American Journal of Sur~ary
Seventh Cranial Nerve
cranial nerve or the great superficial petrosal branch of the seventh cranial nerve-as suggested by some authors [3,7,8] seems unlikely. They reasoned that these nerves normally carry either efferent sensory or efferent visceral fibers. Regrowth across the operative field and reanastomosis seems not to be responsible for the return of facial motion; that is why reexcision of the parotid area after recurrence of the tumor would not interrupt such neural pathways and does not result in paralysis. Martin and Helsper [3] described two such patients in whom a wide, deep portion of tissue was removed from the parotid area at a second excision. This was only ensued by temporary interference with facial motion, and two to four weeks later there was as much voluntary activity as before the second excision. As mentioned previously, there are elaborate anastomoses between the terminal branches of the fifth and seventh cranial nerves in all parts of the facial musculature. Probably after complete and permanent interruption of the facial nerve, voluntary motor impulses by reeducation may find their way from the cortex through the fifth cranial nerve to the respective muscles. All of the terminal branches of the fifth nerve are sensory, and some probably carry “dormant motor fibers.” Martin and Helsper [8] described one patient who had complete function of facial motion after excision of the seventh cranial nerve and its plexus about one year postoperatively. Since there was evidence of recurrence of the tumor, a large area was removed immediately in front of and below the ear down to the masseter muscle. This operation was not followed by interruption of the recovered function of facial motion. Trojaborg and Siemssen [6], using electromyographic studies in four patients who had spontaneous recovery of facial motion after facial palsy due to block dissection of the neck and total parotidectomy for malignant tumor, confirmed the clinical findings and concluded that reinnervation of facial muscles is due to misdirection of regenerating axons from a
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masticator nerve injured at the time of operation into the nearby facial muscles. We believe that the scientific explanation of this phenomenon needs more investigation. Edgerton [9] believes that, with resection of the parotid gland, correction of palsy may be carried out through the surgical wound. We believe that whether or not neurorrhaphy is resorted to, active and consistent practice in front of the mirror favors such recovery of motion. The interval between excision of the facial nerve and the first sign of the facial nerve and the first sign of spontaneous recovery has ranged from six to forty-two months [3,6]. Summary
Spontaneous return of function after surgical excision of the seventh cranial nerve in surgery of parotid tumors is not impossible. This seems to occur through the several existing neural pathways between the fifth and seventh cranial nerves. It is probable that voluntary motor impulses by reeducation find their way from the cortex through the fifth cranial nerve to the respective muscles. References 1. Conley JJ Facial nerve grafting in the treatment of parotid gland tumors: new technique Arch Surg 70: 359, 1955. 2 Conley JJ: Surgical treatment of tumors of the parobd gland with emphasis on immediate nerve grafting West J Surg 63: 534, 1955. 3. Martin H, Helsper JT: Spontaneous return of function following surgical section or excision of the seventh cranial nerve in the surgery of parotid tumors. Ann Surg 146: 715, 1957 4 Conley JJ: Accessory neuromotor pathways to the face. Am Acad Opthalmol Otolaryngol66: 1064, 1964 5. Antia NH, Divekar SG. Dastur DK. The facial nerve In leprosy. I Clinical and operative aspects J Int Lepr 34: 103. 1966. 6 Trojaborg W, Siemssen S: Reinnervation after resection of the facial nerve. Arch Neural 26: 17, 1972. 7 Conley JJ, Papper EM, Kaplan N: Spontaneous return and facial nerve grafting. Arch Otolatyngol77: 643, 1963. 8. Martin HE, Helsper JT: Supplementary report on spontaneous return of function following surgical section or excision of the seventh cranial nerve in surgery of parotid tumors Ann Surg 151: 538, 1960. 9. Edgerton MT. Surgical correction of facial paralysis: a plea for better reconstructions. Ann Surg 165. 985, 1967
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Although relatively rare, it is not impossible for either partial or complete function of the seventh cranial nerve to return after surgical section or excision of this nerve. In this communication we report a case with a review of the English literature. Case Report A forty-three year old male with a ten year history of enlarged parotid gland, was admitted to Soraya Medical Center in January 1964. The parotid gland was as large as an orange, lobulated, hard in consistency, and attached to the deep tissues of the neck. The lymph nodes of the left submandibular area and the left lateral aspect of the neck were enlarged. At operation, frozen section examination revealed malignant neoplastic cells of the parotid gland. On exposure, the main trunk of the facial nerve was completely encompassed by the tumor and we had to sacrifice it. Approximately 2.5 to 3 cm of the nerve and a portion of its distal plexus were resected along with the tumor, followed by a radical neck dissection. Obviously, immediate and complete postoperative paralysis of the corresponding facial musculature ensued. The patient was discharged after a convalescent period of ten days. At one of his follow-up visits two months later, no sign of recurrence of the tumor was evident, but he was still suffering from facial paralysis. We did not see him again until December 1967 when he came to announce that his facial paralysis had improved. Surprisingly there was active movement in all parts of the once paralyzed facial musculature, including a definite wrinkling of the left forehead so that he could raise the eyebrow normally. He could also whistle and show his teeth. He was last observed on January 19, 1974, at which time he was a normal man and confident in his social contacts.
Comments
Spontaneous recovery of the facial movements after sacrifice of the facial nerve has been observed not infrequently, but it has been ascribed to some
From the Department of Surgery, lsfahan University School of Madiona, Isfahan, Iran Reprlnt requests should be addressed to M. Hakamt. MD, Department of Surgery, lsfahan Unwerslty School of Medicine, Isfahan, Iran
394
form of neurorrhaphy. Conley [1,2] in 1955 reported the fact that facial movement had returned to the face after radical extirpation of the parotid gland and facial nerve, without his resorting to rehabilitation of the face. Martin and Helsper [3] speculated that in 28 per cent of the cases studied, the fifth cranial nerve became a functional substitute for the facial nerve. They stated that new motor pathways will be established through the fifth cranial nerve and outlined these pathways as follows: (1) A communication between the auriculotemporal branch of the fifth cranial nerve and the branches of the seventh cranial nerve. (2) A communication between the infratrochlear branch of the ophthalmic nerve (fifth cranial nerve) and the zygomatic branches of the seventh cranial nerve. (3) A communication between the zygomaticofacial branches of the maxillary nerve (fifth cranial nerve) and the zygomaticofacial branches of the seventh cranial nerve. (4) A communication between the zygomaticotemporal branches of the maxillary nerve and the temporal branches of the seventh cranial nerve. (5) A communication between the infraorbital branch of the maxillary nerve and the zygomatic branches of the seventh cranial nerve. (6) A communication between the masticator branch of the mandibular nerve (fifth cranial nerve) and the plexus of the seventh cranial nerve. Conley [4] in 1964 concluded the existence of a secondary or aberrant neuromuscular facility to the mimetic muscles of the face. He stated that this facility is not functional in all patients and the system is independent of the main trunk of the facialnerve peripheral to the geniculate ganglion. Antia, Divekar, and Dastur [5] demonstrated at operative explorations that the facial nerve does not consist of a simple system of branches but rather a network or plexus of branching and reanastomosing fibers. Trojaborg and Siemssen [6] recently stated that reinnervation through the pathways other than the facial motor nerve fibers-via
the semilunar
ganglion
of the fifth
The American Journal of Sur~ary
Seventh Cranial Nerve
cranial nerve or the great superficial petrosal branch of the seventh cranial nerve-as suggested by some authors [3,7,8] seems unlikely. They reasoned that these nerves normally carry either efferent sensory or efferent visceral fibers. Regrowth across the operative field and reanastomosis seems not to be responsible for the return of facial motion; that is why reexcision of the parotid area after recurrence of the tumor would not interrupt such neural pathways and does not result in paralysis. Martin and Helsper [3] described two such patients in whom a wide, deep portion of tissue was removed from the parotid area at a second excision. This was only ensued by temporary interference with facial motion, and two to four weeks later there was as much voluntary activity as before the second excision. As mentioned previously, there are elaborate anastomoses between the terminal branches of the fifth and seventh cranial nerves in all parts of the facial musculature. Probably after complete and permanent interruption of the facial nerve, voluntary motor impulses by reeducation may find their way from the cortex through the fifth cranial nerve to the respective muscles. All of the terminal branches of the fifth nerve are sensory, and some probably carry “dormant motor fibers.” Martin and Helsper [8] described one patient who had complete function of facial motion after excision of the seventh cranial nerve and its plexus about one year postoperatively. Since there was evidence of recurrence of the tumor, a large area was removed immediately in front of and below the ear down to the masseter muscle. This operation was not followed by interruption of the recovered function of facial motion. Trojaborg and Siemssen [6], using electromyographic studies in four patients who had spontaneous recovery of facial motion after facial palsy due to block dissection of the neck and total parotidectomy for malignant tumor, confirmed the clinical findings and concluded that reinnervation of facial muscles is due to misdirection of regenerating axons from a
Volume 132, %#n-baV
1076
masticator nerve injured at the time of operation into the nearby facial muscles. We believe that the scientific explanation of this phenomenon needs more investigation. Edgerton [9] believes that, with resection of the parotid gland, correction of palsy may be carried out through the surgical wound. We believe that whether or not neurorrhaphy is resorted to, active and consistent practice in front of the mirror favors such recovery of motion. The interval between excision of the facial nerve and the first sign of the facial nerve and the first sign of spontaneous recovery has ranged from six to forty-two months [3,6]. Summary
Spontaneous return of function after surgical excision of the seventh cranial nerve in surgery of parotid tumors is not impossible. This seems to occur through the several existing neural pathways between the fifth and seventh cranial nerves. It is probable that voluntary motor impulses by reeducation find their way from the cortex through the fifth cranial nerve to the respective muscles. References 1. Conley JJ Facial nerve grafting in the treatment of parotid gland tumors: new technique Arch Surg 70: 359, 1955. 2 Conley JJ: Surgical treatment of tumors of the parobd gland with emphasis on immediate nerve grafting West J Surg 63: 534, 1955. 3. Martin H, Helsper JT: Spontaneous return of function following surgical section or excision of the seventh cranial nerve in the surgery of parotid tumors. Ann Surg 146: 715, 1957 4 Conley JJ: Accessory neuromotor pathways to the face. Am Acad Opthalmol Otolaryngol66: 1064, 1964 5. Antia NH, Divekar SG. Dastur DK. The facial nerve In leprosy. I Clinical and operative aspects J Int Lepr 34: 103. 1966. 6 Trojaborg W, Siemssen S: Reinnervation after resection of the facial nerve. Arch Neural 26: 17, 1972. 7 Conley JJ, Papper EM, Kaplan N: Spontaneous return and facial nerve grafting. Arch Otolatyngol77: 643, 1963. 8. Martin HE, Helsper JT: Supplementary report on spontaneous return of function following surgical section or excision of the seventh cranial nerve in surgery of parotid tumors Ann Surg 151: 538, 1960. 9. Edgerton MT. Surgical correction of facial paralysis: a plea for better reconstructions. Ann Surg 165. 985, 1967
395