Neuronal structure of microvascular transplants with and without neuronal anastomosis

Neuronal structure of microvascular transplants with and without neuronal anastomosis Alexander Gaggl MD, DDS,a Günter Schultes MD, DDS,a Hans Kärcher MD, DDS, PhD,b Reinhold Kleinert MD, PhD,c Graz, Austria UNIVERSITY HOSPITAL

Objective. Latissimus dorsi transplants have little neuronal regenerative capacity without neuronal anastomosis. Histologic differences between transplants with and without neuronal anastomosis and 2 distinct types of neurosurgical reanastomosis are highlighted in this study. Patients and methods. Fifty-four patients with squamous cell carcinomas of the oral cavity (T4) were treated by tumor resection and homolateral neck dissection. The defect was covered with a microvascular latissimus dorsi transplant. In 15 patients, no neuronal anastomoses were performed. In 21 patients, the thoracodorsal nerves were used for microneurosurgical reanastomosis, whereas in 18 patients, the cutaneous branches of the intercostal nerves were used for microneurosurgical reanastomosis. The transplant was examined during surgery and 9 months after surgery by means of a histologic examination of a biopsy specimen. The number of fascicles, the degree of fibrosis, and the myelination were examined. Furthermore, a neurosensory examination was performed 9 months after surgery. Results. Overall, our patients had an average of 12.1 fascicles during surgery. After surgery, patients without neuronal anastomosis showed an average of 4.9 fascicles, patients with nerve anastomosis to the cutaneous branches of the intercostal nerve showed an average of 6.2 fascicles, and patients with anastomosis to the thoracodorsal nerve showed an average of 9.6 fascicles. In cases of nerve anastomosis, a lesser degree of fibrosis was found, together with good myelinization. The clinical examination showed the best neurosensory function in the transplants with anastomosis to the thoracodorsal nerve and the worst function in those without neuronal anastomosis. Conclusion. Neuronal reanastomosis led to more surviving neuronal structures in the postoperative histologic specimen. The highest density of fascicles was found in the well vascularized thoracodorsal nerve. The neurosensory function agrees with the histologic result.

(Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:25-32)

Microvascular transplants have a widely differing capacity of reinnervation without neuronal reanastomosis, depending on the transplant size and type. In the case of smaller fasciocutaneous transplants from the forearm, Baumann1 found a good spontaneous reestablishment of sensitivity without additional neuromicrosurgical anastomosis of the transplants. However, even in the case of smaller transplants, an improvement in neuronal capacity can be achieved by nerve anastomosis. Anastomosis of the sensitive nerves of a microvascular forearm transplant can result in fewer postoperative complications and improved neuronal differentiation abilities.2-4 Reestablishment of sensitivity in small and thin transplants appears to be possible without neuronal anastomosis, but higher discrimination is only achieved by neuronal anastomosis. In voluminous latissimus dorsi aOral Maxillofacial Surgeon, Department of Oral and Maxillofacial Surgery, University Clinics, Graz. bHead, Department of Oral and Maxillofacial Surgery, University Clinics, Graz. cHead, Laboratory of Neuropathology, University Clinics, Graz. Received for publication Dec 8, 1998; returned for revision Feb 10, 1999; accepted for publication Feb 23, 2000. Copyright © 2000 by Mosby, Inc. 1079-2104/2000/$12.00 + 0 7/12/107225 doi:10.1067/moe.2000.107225

transplants, spontaneous reestablishment of sensitivity is hardly to be expected, or only to a small degree, in contrast to radial transplants.5,6 If neuronal regeneration is required, neuronal reanastomosis must be carried out. Local sensory and motor nerves of the shoulder region may be used for neuronal reanastomosis. The cutaneous branches of the intercostal nerves are responsible for sensory innervation of transplant skin and are severed on removal of the transplant. No additional trauma to the patient is caused when these terminal branches of the spinal nerve are dissected as nerve transplants. The thoracodorsal nerve is an alternative nerve transplant from the shoulder region. It can be dissected and removed, together with the vascular pedicle of the latissimus dorsi transplant.7 It is the aim of this study to determine which nerve is better suited for nerve transplantation and to determine histologic differences in the transplants, as well as to determine what neuronal function can be achieved without neuronal anastomosis. Furthermore, the differences in the histologic specimen should be verified by testing the neurosensory function.

PATIENTS AND METHODS Fifty-four patients with an oral carcinoma were treated by extensive tumor resection. The facial recon25

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Fig 1. Free pedicled scapula latissimus dorsi transplant with thoracodosal artery (1), vein (2), and nerve (3).

Fig 2. Osteomyocutaneous scapula latissimus dorsi transplant with cutaneous branches of intercostal nerves (1).

Fig 3. Fascicle of latissimus dorsi transplant without neuronal anastomosis. Fascicle shows much fibrosis (1), which can be seen by dark color. There are no myelin sheets. Capillary (2) (magnification ×3.6).

struction was performed by a microvascular osteomyocutaneous scapula latissimus dorsi transplantation. The average age at the time of diagnosis was 60 years (range, 40-71 years). All patients had a squamous cell carcinoma of the mandibular alveolar ridge or of the floor of the mouth, staged T4N2aM0. Partial resection of the mandible, radical homolateral neck dissection, and suprahyoid homolateral block removal were carried out in each patient. Primary defect reconstruction was carried out by a microvascular pedicled osteomyocutaneous scapula latissimus dorsi transplantation with

neuronal reanastomosis in 39 patients and in 15 patients without neuronal reanastomosis (mean age, 62 years). Arterial anastomosis was carried out between the thoracodorsal artery and the superior thyroid artery, and venous anastomosis was carried out between the thoracodorsal and external jugular vein. Neuronal anastomosis was carried out between the proximal stump of the large auricular nerve and the thoracodorsal nerve in 21 patients (mean age, 57 years) (Fig 1), and in another 18 patients it was carried out between the large auricular nerve and a central cutaneous branch of the inter-

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Fig 4. Fascicle of latissimus dorsi transplant with neuronal anastomosis between large auricular nerve and lateral intercostal branches. Low grade of fibrosis (1); myelin sheet can be seen (2); fat cells (3) (magnification ×3.6).

Fig 5. Fascicle of latissimus dorsi transplant with neuronal anastomosis between large auricular nerve and thoracodorsal nerve. Low grade of fibrosis (1); myelin sheets well preserved (2) (magnification ×3.6).

costal nerve (mean age, 60 years) (Fig 2). Dissection and removal of these nerves was carried out simultaneously with the microvascular transplantation. Nerve surgery was carried out by the same surgeon in every

case. After a straightforward primary healing period, all patients were treated by radiotherapy of the cervical lymph node region an average of 10 weeks after surgery (range, 9-14 weeks), with a 60-Gy total area dosis.

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Fig 6. Another fascicle of latissimus dorsi transplant with neuronal anastomosis between large auricular nerve and thoracodorsal nerve. Ranvier rings can be seen clearly (1) (magnification ×3.6).

Table I. Postoperative histologic results of patients without neuronal anastomosis Number

Kind of transplant

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

Neuronal Time from operation anastomosis to histologic work up 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

Histological examination Biopsy specimens of the transplanted skin were taken intraoperatively and again postoperatively after primary healing to evaluate the number of fascicles, the degree of fibrosis, and the myelinization. The degree of fibrosis was classified as very low (up to 30% of the fascicle), low (30% - 60%), and high (>60%). The histologic workup was done with a Masson Trichrom stain so that fascicles of a diameter of 25 µm could be seen. Twenty histologic specimens of a 2-cm piece of

12 5 9 10 10 9 9 10 9 9 13 10 8 10 10

Fascicles

Grade of fibrosis

Demyelination

4 7 6 4 5 4 3 6 6 5 5 4 6 5 4

High High High High High High High High High High High High High High High

Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

skin were examined. The histologic results of patients with both types of nerve anastomosis were also compared with those with a vascularized latissimus dorsi transplant without nerve anastomosis. All specimens were examined by one neuropathologist. The average elapsed time between the transplantation and the histologic examination was 9 months.

Neurosensory examination All patients were given a clinical neurosensory

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Table II. Postoperative histologic results of patients with neuronal anastomosis to thoracodorsal nerve Time from operation to histologic Grade work up Fascicles of fibrosis Demyelination

Number

Kind of transplant

Neuronal anastomosis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve

8 9 6.5 5 7 8 10 9 9 7 9 10 10 9 10 9 10 8 9 9 10

11 9 7 8 10 10 10 11 9 9 11 10 9 10 8 10 10 10 11 10 8

Low Low Very low Low Low Low Low Low Low Low Low Low Very low Low Very low Low Very low Low Low Very low Very low

No No No No No No No No No No No No No No No No No No No No No

Table III. Postoperative histologic results of patients with neuronal anastomosis to intercostal nerve Time from operation to histologic Grade of work up Fascicles fibrosis Demyelination

Number

Kind of transplant

Neuronal anastomosis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve

examination scheme to assess neuronal regeneration a mean of 9 months after surgery. Clinical evaluation of sensitivity in the myocutaneous part of the transplant was carried out with numerous steps. Pain sensation and differentiation were tested by prodding with a dental probe. Pain sensation was classified as sharp or gnawing. Temperature sensation was tested by asking the patient to differentiate cold (carbon

8 8 8 5 7 9 9 9 8 10 8 7 9 10 9 9 10 9

6 5 7 8 6 5 5 5 6 7 8 7 5 5 6 8 7 6

Low Low Low Low Low Low Low Low Low Low Low Low Low Low Low Low Low Low

No No No No No No No No No No No No No No No No No No

dioxide snow) and heat (a spatula heated to 60°C). Pressure and touch sensations were tested by dental probes. Rough and slight pressure was exerted with the blunt end of the dental probe with rough (ie, strong) pressure to the transplant and slight (ie, pressureless) resting of the dental probe on the transplant. Two-point discrimination was also verified. To compare physiologic differentiation, the contralateral

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Table IV. Clinical results after transplantation without neuronal anastomosis Number

Kind of transplant

Neuronal anastomosis

Time from operation to neurosensory examination

Clinical result

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

12 5 9 10 10 9 9 10 9 9 13 10 8 10 10

0 P P 0 0 0 0 0 0 P 0 0 0 0 0

P, Pressure, pain. 0, No somatosensory function.

Table V. Clinical results after transplantation and neuronal anastomosis to thoracodorsal nerve Number

Kind of transplant

Neuronal anastomosis

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve Thoracodorsal nerve > > large auricular nerve

Time from operation to neurosensory examination 8 9 6.5 5 7 8 10 9 9 7 9 10 10 9 10 9 10 8 9 9 10

Clinical result *** *** ** ** ** *** *** *** ** ** *** *** ** *** *** *** ** ** *** *** **

**Two-point discrimination, vibration. ***Temperature.

mucous membranes were tested. With a 2-point compass, simultaneous stimuli were applied. The shortest distance identifying 2 separate points was measured in millimeters and was identified as the discrimination point. By applying a 60-Hz tuning fork, the sense of vibration in the transplant was tested. The examinations described above were carried out before a biopsy was performed.

RESULTS Histologic results On average, 12.1 fascicles (8 - 14) were found in specimens taken before surgery from the latissimus dorsi transplant. The degree of fibrosis and the myelinization were classified as normal. After surgery, 4.9 (s = 1.06) fascicles were found in transplants without nerve anastomosis. These transplants showed a high

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Table VI. Clinical results after transplantation and neuronal anastomosis to cutaneous branches of intercostal nerves Number

Kind of transplant

Neuronal anastomosis

Time from operation to neurosensory examination

Clinical result

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant Latissimus dorsi transplant

Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve Intercostal nerve > > large auricular nerve

8 8 8 5 7 9 9 9 8 10 8 7 9 10 9 9 10 9

* * ** ** * * * * ** ** * ** * * * ** * *

*Pressure, pain. **Two-point discrimination, vibration.

degree of fibrosis and reduced myelinization of axons (Fig 3). The average number of fascicles in transplants with neuronal anastomosis of cutaneous intercostal nerve branches was 6.2 (s = 1.08). Little fibrosis and no demyelinization were found (Fig 4). In cases of anastomosis of the thoracodorsal nerve, 9.6 (s = 1.09) fascicles were detected (Fig 5 and 6). Only a mild degree of fibrosis of fascicles was found in this group. No demyelination was detected. Individual results are shown in Tables I to III.

Neurosensory examination On clinical examination, only 3 patients without neuronal anastomosis had neurosensory function in the transplant area. Only pressure and pain were felt by these patients. In the group with neuronal anastomosis to the cutaneous branches of the intercostal nerves, 12 patients felt pain and pressure, and 6 patients had the possibility of 2-point discrimination and vibration. In the group with neuronal anastomosis to the thoracodorsal nerve, 12 patients showed a complete return of sensitivity (pressure, pain, 2-point discrimination, vibration, and temperature). Nine patients felt pressure, pain, 2-point discrimination, and vibration, but no temperature. The results of the neurosensory testing are shown in Tables III to VI. DISCUSSION One of the main characteristics of denerved transplanted tissue is rarefaction and scarring of peripheral neuronal structures. In contrast, functionally superior

transplants with nerve reconstruction show a larger number of neurons and a reduced degree of fibrosis. Katou et al8 and Li et al9 showed that free-transplanted microvascular soft tissue transplants exhibited a higher density of neurons and better myelination after neuronal anastomosis. As early as 1988, Shibata et al10 found that a higher axon number implies improved clinical function. Similar results were found on histologic examination of patients with reinnervated latissimus dorsi transplants. Neuronally anastomosed transplants were superior to those without nerve anastomosis. In cases with neuronal anastomosis to the thoracodorsal nerve, the fascicle number was only slightly reduced. Myelin sheets in fascicles of transplants without nerve anastomosis were markedly reduced. Neuronal anastomosis of both described nerve transplants leads to reduced fibrosis of fascicles. In specimens of patients without nerve anastomosis, a high degree of fibrosis was found on histologic examination. Terzis et al11 described a definite increase in Schwann cells, a reduced fibroblast infiltration, and a higher rate of axonal regeneration in case of vascularized pedicled nerve transplants. In 1995, Gailliot and Core12 also found an increased axon diameter and myelin sheet thickness in pedicled nerve transplants. In our study, anastomosis of the vascularly supplied thoracodorsal nerve transplant was superior to the cutaneous branches of the intercostal nerves, which do not have a dominant perfusion. A greater number of vital axon structures were found, with only slight scarring and good myelination. According to AskoSeljavaara et al,5 a neuronally weak transplant can turn

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into a vital and sensitive transplant through anastomosis of local nerves. This leads to a greatly improved standard of living, as found by Cordeiro et al.13 The transplantation of vascularized nerves is especially advantageous in the case of patients exposed to radiotherapy, as stated by Millesi.14 The phenomenon of good neuronal regeneration in the case of anastomosis of a motor nerve with a sensitive proximal nerve stump is to be analyzed in the future. In summary, it must be stated that the superior histologic results favor nerval anastomosis of the latissimus dorsi transplant. A well vascularized nerve is preferable.

6. Schultes G, Kärcher H, Gaggl A. Postoperative sensibilität des gefäßgestielten m.-latissimus-dorsi-transplantates ohne neuronale anastomose. Mund Kiefer Gesichtschir 1998;2:238-41. 7. Schultes G, Kärcher H, Gaggl A. Anatomische studie des gefäßgestielten nervus thoracicus longus. Stomatol 1998;95:403-9. 8. Katou F, Shirai N, Kamakura S, Ohki H, Motegi K, Andoh N, et al. Intraoral reconstruction with inervated forearm flap: a comparison of sensibility and reinnervation in innervated versus noninnervated forearm flap. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1995;80:638-44. 9. Li XY, Li HY, Chen SZ. Electron microscopic observation of the denervated flap reinnervation after implantation of the sensory nerve. Chung-Hua-I-Hsueh-Tsa-Chih 1994;74:624-5, 647-8. 10. Shibata M, Tsai TM, Firelli J, Breidenbach WC. Experimental comparison of vascularized and non vascularized nerve grafting. J Hand Surg Am 198813:358-65. 11. Terzis JK, Skoulis TG, Soucacos PN. Vascularized nerve grafts. A review. Int Angiol 1995;14:264-77. 12. Gailliot RV Jr, Core GB. Serratus anterior intercostal nerve graft: a new vascularized nerve graft. Ann Plast Surg 1995;35:26-31. 13. Cordeiro PG, Schwartz M, Neves RL, Tuma R. A comparison of donor and recipient site sensation in free tissue reconstruction of the oral cavity. Ann Plast Surg 1997;39:461-8. 14. Millesi H. The current state of nerve microsurgery. In: Riediger D, Ehrenfeld M, editors. Microsurgical tissue transplantation. Chicago: Quintessence; 1989. p. 159-75.

REFERENCES 1. Baumann I, Greschniok A, Bootz F, Kaiserling E. Frei transplantierte, mikrovaskulär reanastomosierte Unterarmlappen zur Rekonstruktion in Mundhöhle und Oropharynx. Klinische und morphologische Befunde unter besonderer Berücksichtigung der Resensibilisierung. HNO 1996;44:616-23. 2. Boyd B, Mulholland S, Gullane P, Irish J, Kelly L, Rotstein L, et al. Reinnervated lateral antebrachial cutaneous neurosome flaps in oral reconstruction: are we making sense? Plast Reconstr Surg 1994;93:1350-7. 3. Dubner S, Heller KS. Reinnervated radial forearm free flaps in head and neck reconstruction. J Reconstr Microsurg 1992;8:467-73. 4. Urken ML, Weinberg H, Vickery C, Biller HF. The neurofasciocutaneous radial forearm flap in head and neck reconstruction. A preliminary report. Laryngoscope 1990;100:161-4. 5. Asko-Seljavaara S, Ryynanen A, Sundell B. Latissimus dorsi musculocutaneous flap used as a pedicled or free microvascular graft. Ann Chir Gynaecol 1982;71:44-50.

Reprint requests: Alexander Gaggl, MD, DDS Klinische Abteilung für MundKiefer- und Gesichtschirurgie der Universitätsklinik für ZMK Auenbruggerplatz 7 A-8036 Graz, Austria