[Applied anatomy for the reinnervation of posterior cricoarytenoid muscle by phrenic nerve for bilateral vocal cord paralysis].
OBJECTIVE
To study the anatomic basis for the anastomosis of phrenic nerve (PN) to the anterior branch of recurrent laryngeal nerve(RLN) for the treatment of the injured bilateral RLN.


METHODS
The origin and the nutritive arteries and the adjacent tissue construction of PNs in 46 cases were studied. The longest utilizable length of PNs and the distance from the root of PN to cricothyroid joint were measured. The sectional area and the number of myelinated fibers of PNs and the anterior branch of RLNs were measured by computer image processing system.


RESULTS
PNs coming from C4 comprised of 93.5%, 95.6% (44/46) of the nutritive arteries came from the ascending carotid artery and got into the cervical segment of PN from its root. The common trunk of PN was very deep, to the external of the common carotid artery and the vertebral vein, and deep to the internal jugular vein and thoracic duct (left), and in the superficies of the subclavian artery and in the deep of the subclavian vein when it was crossing the thoracic entrance. The distance from the root of PN to the level of the subclavian vein and to cricothyroid joint were (7.2 +/- 1.6) cm and (5.5 +/- 1.4) cm, respectively. The former was at least 1.5 cm longer than the latter. The average number of myelinated fibers and the sectional area of the PNs were 2.41 times and 2.15 times as many as those of the anterior branch of RLNs, respectively. The single-fasciculated PNs comprised of about 75.0% (18/24)).


CONCLUSIONS
Clinically, it may be safe and available for cutting PN off at the level of the subclavian vein. The length of PN is enough for the anastomosis of PN to the anterior branch of RLN.
Chen
Shicai
S
Department of Otorhinolaryngology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Zheng
Hongliang
H
Zhou
Shuimiao
S
Li
Zhaoji
Z
Zhang
Suqin
S
Jiang
Zonglai
Z
D000328:Adult; D006801:Humans; D007821:Laryngeal Muscles / Q000294:innervation; D007825:Laryngectomy; D009416:Nerve Regeneration; D010791:Phrenic Nerve / Q000033:anatomy & histology* / Q000601:surgery; D012009:Recurrent Laryngeal Nerve / Q000033:anatomy & histology / Q000601:surgery*; D014826:Vocal Cord Paralysis / Q000601:surgery*