Salivary MMP-9 in the detection of oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most common malignant tumour of the oral cavity. Detection of OSCC is currently based on clinical oral examination combined with histopathological evaluation of a biopsy sample. Direct contact between saliva and the oral cancer makes measurement of salivary metalloproteinase-9 (MMP-9) an attractive alternative. MATERIAL AND METHODS: In total, 30 OSCC patients and 30 healthy controls were included in this prospective study. Saliva samples from both groups were collected, centrifuged and supernatant fluid was subjected to ELISA for assessment of MMP-9. The median salivary MMP-9 values with interquartile range (IQR) of OSCC patients and the control group were statistically analysed using the Mann-Whitney U-test. The receiver operating characteristic (ROC) curve was constructed and the area under curve (AUC) was computed. RESULTS: The median absorbance MMP-9 value of the OSCC group was 0.186 (IQR= 0.158) and that of control group was 0.156 (IQR=0.102). MMP-9 was significantly increased in the OSCC patients than in the controls by +19.2% (p=0.008). Median values in patients with recurrence and in patients with primary event were 0.233 (IQR=0.299) and 0.186 (IQR=0.134) respectively. MMP-9 was significantly increased in patients with primary event (p=0.017) compared to controls by +19.2%. No significant increase of MMP-9 level was detected when comparing patients with recurrence and healthy controls (+49.4%; p=0.074). The sensitivity value of MMP-9 was 100% whereas the specificity value was 26.7% with AUC of 0.698. CONCLUSIONS: The present data indicates that the elevation of salivary levels of MMP-9 may be a useful adjunctive diagnostic tool for detection of OSCC. However, further studies are necessary to provide scientific and clinical validation.

Longterm quality of life after oncologic surgery and microvascular free flap reconstruction in patients with oral squamous cell carcinoma.

BACKGROUND: Quality of life (QoL) has become increasingly important in cancer treatment. It refers to the patient's perception of the effects of the disease and therapy, and their impact on daily functioning and general feeling of well being. MATERIAL AND METHODS: In this prospective study, a total of 100 patients treated at our institution, completed the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire and the specific EORTC QLQ-H&N35 module. The questionnaires were distributed to the patients between 12 and 60 months postoperatively. RESULTS: Global QoL score was 58.3 deterioration and mean score for functioning scale was 76.7. Fatigue (28.7 ± 26.1), followed by financial problems (27.7 ± 33.5), insomnia (26.7 ± 34.5) and pain (26.3 ± 29.9) had highest symptom score on QLQ-C30. Fatigue (r=-0.488), insomnia (r=-0.416) and pain (r =-0.448) showed highest value for significantly negative correlation to global QoL. In the H&N35 module, restriction of mouth opening (43.3 ± 38.6), dry mouth (40.7 ± 36.9), sticky saliva (37.3 ± 37.1) and eating in public (33.8 ± 31.9) were the four worst symptoms. Swallowing problem (r=-0.438), eating in public (r=-0.420) and persistent severe speech (r=-0.398) ranked as the three worst symptoms with highest value for significantly negative correlation to global QoL. CONCLUSIONS: Longterm QoL after oncologic surgery and microvascular free flap reconstruction in patients with oral cancer is satisfactory. Measurung QoL should be considered as part of the evaluation of cancer treatment.

Wearing complete dental prostheses - Effects on perioral morphology.

BACKGROUND: To adequately perform rehabilitation of edentulous patients by a complete removable dental prosthesis (CRDP) is from basic interest to dentists to understand the morphologic changes caused by re-establishment of a physiologic jaw relationship. Anthropometric analyses of standardized frontal view and profile photographs may help elucidate such changes. MATERIAL AND METHODS: Photographs of 31 edentulous patients were compared in relaxed lip closure and after insertion of a CRDP in stable occlusion. 2232 anthropometric distances were raised. Eighteen anthropometric indices reflecting the perioral morphology and its integration in the vertical facial harmony were investigated. RESULTS: The intercanthal - mouth width index (p>.001), medial - lateral cutaneous upper lip height index (p=.007), lower vermilion contour index (p=.022), vermilion - total upper lip height index (p=.018), cutaneous - total upper lip height index (p=.023), upper lip - nose height index (p=.001), nose - upper face height index (p=.002), chin - mandible height index (p=.013), upper lip - mandible height index (p=.045), nose - lower face height index (p=.018), and nose - face height index (p=.029) showed significant pre- to post-treatment changes. CONCLUSIONS: The investigated anthropometric indices presented reproducible results related to an increase in occlusal vertical dimension. Their application may be helpful in assessment, planning, and explanation of morphologic effects of CRDPs on the perioral and overall facial morphology, which may helps to improve the aesthetic outcome.

First experience using a novel microsurgical robotic device for free flap surgery in cranio- and maxillofacial surgery.

Many surgical fields profit from robotic support devices. After the first case reports about the use of a special microsurgical roboter (Symani Sugrical System, Medical Microinstruments, Pisa, Italy) we evaluated the potential of such a device in cranio- and maxillofacial surgery in a world's first single-center case series. This novel piece of equipment is meant to assist the surgeon anastomosing small vessels, nerves and lymphatic vessels. In total 30 free flaps were performed and compared to another 30 conventionally anastomosed free flaps. In total 127 anastomoses were surveyed. We encountered a lot of potential for robotic supported operations in the field of cranio- and maxillofacial surgery. However, the surgery time for robotic supported anastomosis with an average time of 32.5 min to perform arterial anastomosis was significant longer than the conventional ones, which needed 11.8 min on average. Tremor Filter and Motion Scaling are promising features for future microsurgery but the grip of the microinstruments has to be improved. It remains to be seen if the potential will be validated after the upcoming learning period and if robotic support devices will prevail in cranio- and maxillofacial surgery.

Parotidectomy and submandibulectomy for benign diseases in Thuringia, Germany: a population-based study on epidemiology and outcome.

Although salivary gland surgery for benign diseases is an integral part of clinical routine of head and neck surgeons, there is not many population-based data published on incidence and efficiency of this surgery. Parotidectomy was performed in 180 patients and submandibulectomy in 97 patients for benign diseases in eight otorhinolaryngology and two maxillofacial surgery departments in Thuringia, Germany, in 2005. All patients were analysed regarding patients' characteristics, therapy, complications and further course of disease. Predominant indications were epithelial tumours for parotidectomy (79 %) and sialolithiasis for submandibulectomy (50 %). The most frequent tumour types were pleomorphic adenoma (46 %) and Warthin tumours (29 %). Pleomorphic adenoma was significantly more frequent in female patients and Warthin tumours in male patients and smokers. The incidence of parotidectomy, i.e. the surgical rate, was 7.8/100,000 habitants and of submandibulectomy 4.1/100,000 habitants. One hundred and seventy-eight tumours including 154 epithelial tumours resulted in an incidence of 7.6/100,000 habitants for all treated tumours and of 6.6/100,000 for epithelial tumours, respectively. The majority of parotid cases were treated by lateral parotidectomy (79 %). Relevant complications were observed in 22 % of patients. After parotidectomy and submandibulectomy a postoperative facial palsy was observed in 28 and 2 % of cases, respectively. Only 1 % was permanent. During a mean follow-up time of 9.6 months, 3 % of parotidectomy patients developed a Frey's syndrome needing treatment and 0.8 % developed a tumour recurrence. This population-based analysis shows that salivary gland surgery is performed in higher incidence than expected, effectively and with low-risk in daily routine of head and neck surgeons.

Clinical-anthropometric and aesthetic analysis of nose and lip in unilateral cleft lip and palate patients.

OBJECTIVE: Presentation of a technique to determine objectively the degree of symmetry in the area of nose and lip in cleft patients based on analysis of photographs. To compare the objective measurements with the subjective impression. DESIGN: This was a retrospective study using a predefined photo documentation standard to capture images of the area of nose and lip. SETTING: Department of Oral and Maxillofacial Surgery, University of Jena, Germany. PATIENTS: Unilateral cleft patients following primary lip repair (group 1; n  =  36) or secondary correction (group 2; n  =  23). MAIN OUTCOME MEASURES: Measurements were taken on standardized photographs of three dimensions in the area of the nose and two dimensions in the upper lip region. Sign tests were used to ascertain differences between the cleft and unaffected sides separately for each group. Subjective impressions regarding symmetry were gathered and quantified by means of a visual analog scale (VAS). The Mann-Whitney U test was employed to compare the observers' impressions between the two groups. RESULTS: While significant side differences were found for all distances in group 1, only the side differences in the height of the nostril remained significant in group 2. Subjective evaluation of the nostril area improved significantly following corrective surgery. However, no such change in the area of the upper lip was recognized by the observers. CONCLUSIONS: We were able to demonstrate that the measurable symmetry of the nostril area, as well as the upper lip, was significantly enhanced by corrective surgery. However, only the subjective impression of the nostril was improved.

Scapular free flap as a good choice for mandibular reconstruction: 119 out of 280 cases after resection of oral squamous cell carcinoma in a single institution.

Microsurgical procedures for reconstruction after resection of head and neck tumours have become standardised and reliable. Among them, the scapular free flap is used less often, mostly to avoid excessive operating times. We hypothesise that complex reconstructions after resection of oral squamous cell carcinoma (OSCC) are successful even with time-consuming free flaps such as the scapular free flap. In this retrospective, single-centre study, we used the evaluation of medical records to investigate the postoperative outcome of microvascular reconstruction after ablative surgery of OSCC. Associations among the categorical variables were analysed using Pearson's chi squared test or Fisher's exact test. Among the continuous variables, the t test or Mann-Whitney U test were used as appropriate. For multivariate analysis, the logistic regression model was calculated. In the sample of 280 free flap reconstructions, we performed 142 radial forearm and 119 scapular free flaps. The American Society of Anesthesiology (ASA) score (p=0.006) and the duration of the operation (p=0.010) are independent factors which influence the need for operative revisions. The type of free flap is irrelevant for that. With 4.2% flap losses, scapular free flaps were successful; even in patients ≥ 70 years old (0 flap losses). Complex reconstructions after surgical resection of OSCC are successful even in aged patients. The scapular free flap is a good choice for mandibular reconstruction despite the time-consuming intraoperative repositioning of the patient. In an increasingly ageing group of patients, who have more vascular diseases, scapular free flaps could be a very successful alternative after ablative surgery of oral squamous cell carcinoma.

Evaluation of substitutes for bone: comparison of microradiographic and histological assessments.

We created defects of standard size in the frontal bones of adult pigs and filled them with four different materials. On six occasions (at 1, 2, 4, 8, 12, and 26 weeks), samples were harvested, and evaluated by computing microradiographic images. We examined the specimens histologically as controls. After insertion of anorganic materials, microradiographic evaluation was easy and precise, and there were no significant differences between them and the histological controls (p=0.2). A quantitative evaluation of chemically sterilised bone by computer was not possible for more than 4 weeks.

VEGF transfer based on gene-modified fibroblasts using a hypoxia-induced vector to modulate neoangiogenesis in ischaemic regions of myocutaneous transplants.

The effect of a hypoxia-inducible VEGF-expressing on wound healing in an ischaemic hind leg rat model was evaluated in this study. 180 Wistar rats were assigned randomly to three groups. After ligation of the femoral artery, group 1 received pRTP801-VEGF165, group 2 untransfected fibroblasts, group 3 saline; injection was into the subcutaneous tissue, proximal and distal to the artery ligation. Biopsy specimens were obtained on days 3, 5, 7, 14 after implementation. VEGF transgene expression, vessel architecture, the amount and total area of vessel formation were investigated. Results showed a significantly higher level of VEGF protein expression in group 1 compared to group 2 (P≤0.001) throughout the investigational period. Group 1 exhibited a significant growth of CD31-positive blood vessels in the subcutaneous tissue on day 14 compared to groups 2 and 3 (P≤0.001) (group 1, 62.20±1.92; group 2, 20.60±1.67; group 3, 12.40±1.14). Alpha-SMA-positive staining also showed significant vessel growth in group 1 on day 5 (group 1, 27.00±1.87; group 2, 7.20±1.48; group 3, 10.00±1.73). These results were confirmed in the distal muscle tissue. No significant results were obtained for the proximal muscle tissue. The subcutaneous application of pRTP801-VEGF165 showed a long-lasting effect, with an increased expression of VEGF over the entire observation period. It appears that the use of fibroblasts transfected with VEGF is a promising way to increase early angiogenesis in ischaemic tissue.

Tissue hypoxia in complex regional pain syndrome.

Untreated complex regional pain syndrome (CRPS) may progress from acute stages with increased hair and nail growth in the affected limb to chronic stages with atrophy of the skin, muscles and bones. The aim of this study was to investigate whether tissue hypoxia could be one mechanism responsible for this late CRPS symptoms. Nineteen patients with CRPS and two control groups (healthy control subjects, surgery patients with edema) participated in this study. Skin capillary hemoglobin oxygenation (HbO(2)) was measured non-invasively employing micro-lightguide spectrophotometry (EMPHO). The EMPHO probe was mounted force-controlled onto the skin of the affected and unaffected hand. HbO(2) was measured at rest and during postischemic reactive hyperemia. HbO(2) did not differ between the right (58.20%+/-1.12) and left (57.79%+/-1.31, ns) hand in control subjects. However, in patients, HbO(2) of the affected side (36.63%+/-2.16) was significantly decreased as compared to the clinically unaffected side (46.35%+/-2.97, P<0.01). As compared to controls, HbO(2) in CRPS was reduced on both sides (P<0.001). Postischemic hyperoxygenation was impaired on the affected side in CRPS (60.81%+/-2.90)--as compared to the unaffected side (67.73%+/-1.50, P<0.04) and to controls (68.63%+/-0.87, P<0.005). The unaffected limb in CRPS did not differ from controls. Despite skin edema, pre- (49.06%+/-2.02) and postsurgery HbO(2) (53.15%+/-4.44, ns) were not different in the second control group. Our results indicate skin hypoxia in CRPS. Impairment of nutritive blood flow in the affected limb may be one factor contributing to atrophy and ulceration in chronic CRPS. The investigation of patients after surgery revealed that edema could not be the only reason for hypoxia.

Dose-dependent biphasic induction and transcriptional activity of nuclear factor kappa B (NF-kappaB) in EA.hy.926 endothelial cells after low-dose X-irradiation.

PURPOSE: Low-dose radiotherapy is known to exert an anti-inflammatory effect, but the underlying radiobiological mechanisms are still elusive. It was recently reported that transforming growth factor (TGF) beta1 essentially contributes to the reduced adhesion of peripheral blood mononuclear cells to endothelial cells at low-dose X-irradiation. As the transcription factor nuclear factor kappa B (NF-kappaB) is crucially involved in mediating an inflammatory response by inducing the expression of cytokines and adhesion molecules, NF-kappaB DNA binding and transcriptional activity as well as its impact on the expression of TGF-beta1 in EA.hy.926 endothelial cells were analysed subsequently to low-dose radiotherapy. MATERIALS AND METHODS: Human EA.hy.926 endothelial cells were grown to subconfluence. Twenty hours after X-irradiation with single doses ranging from 0.3 to 3 Gy, the cells were activated with tumour necrosis factor-alpha. Four hours later, the cells were harvested. NF-kappaB DNA-binding activity of nuclear extracts was analysed by electrophoretic mobility shift assay. The NF-kappaB subunits p50, p65/RelA, c-Rel and RelB of the NF-kappaB complexes were quantified by enzyme-linked immunoabsorbant assay. The transcriptional activity of NF-kappaB was measured using luciferase reporter gene assays in EA.hy.926 endothelial cells transiently transfected with the plasmid pB2xLuc. To correlate transcriptional activity to TGF-beta1 expression, NF-kappaB decoy oligonucleotides were used to inhibit NF-kappaB activity and TGF-beta1 secretion. RESULTS: After low-dose radiotherapy, an increased NF-kappaB DNA-binding activity was observed in stimulated EA.hy.926 endothelial cells with a relative maximum (threefold induction) at 0.5 Gy. The NF-kappaB activation then decreased after X-irradiation at 0.6-0.8 Gy and subsequently increased again at doses of 1 and 3 Gy. This biphasic induction profile of NF-kappaB was confirmed by the analysis of the NF-kappaB-specific transcriptional activity. The latter showed a relative maximum at 0.5 Gy, a relative minimum between 0.5 and 1.0 Gy, and an increase at 3 Gy. Transfection of EA.hy.926 endothelial cells with NF-kappaB decoy oligonucleotides before irradiation resulted in a 50% reduction of TGF-beta1 secretion at 0.5 Gy compared with control oligonucleotides or untreated cells. CONCLUSIONS: Low-dose radiotherapy induces a biphasic activation of NF-kappaB with a relative maximum at 0.5 Gy. The induction by NF-kappaB of TGF-beta1 in endothelial cells might contribute to the anti-inflammatory properties of low-dose ionizing irradiation.

Prospective study on post-traumatic and postoperative sensory disturbances of the inferior alveolar nerve and infraorbital nerve in mandibular and midfacial fractures.

In a prospective study (January 1999 to December 1997), 34 patients with 26 mandibular and 20 midfacial fractures were investigated. All the fractures were managed by osteosynthesis. To evaluate the incidence and duration of recovery of post-traumatic and postoperative sensory disturbances, the following tests were carried out: sharp/blunt testing, and the two-point discrimination test as conventional clinical examination methods, and electromyographic recording of the masseter reflex to calibrate the clinical findings. To establish the sensory status of the inferior alveolar and the infraorbital nerves in the region of the fracture, and on the intact and control sides, the tests were performed pre-operatively and postoperatively on the seventh day, after 4 weeks and after 3, 6 and 12 months. The incidence of post-traumatic sensory disturbance was 46% for mandibular fractures and 65% for fractures to the midface (sharp/blunt test, two-point discrimination test). The rate of postoperative sensory disturbance in surgical treatment of mandibular fracture involving the region of the intra bony course of the inferior alveolar nerve, including the post-traumatic sensory disturbance, was 76.9%, and 55% following surgical treatment of midfacial fractures. The incidence of persistent sensory disturbances following surgical treatment was 7.7% in the case of mandibular fractures, and 15% in the case of midfacial fractures (sharp/blunt test, two-point discrimination test, masseter reflex). Recovery of neurological function is delayed in the presence of a displaced fracture (> 1 mm) as compared with non-displaced fractures. For the postoperative calibration of sensory disturbances, electromyographic recording of the masseter reflex from the fourth postoperative week onwards has proved useful.

The role of angiography in the lower extremity using free vascularized fibular transplants for mandibular reconstruction.

BACKGROUND: Fibular osteocutaneous free tissue transfer represents the work horse procedure in the reconstruction of large oromandibular defects. Before the fibula is harvested the blood supply of the lower leg and foot should be examined, as the perfusion may be based predominantly on the peroneal artery and venae comitantes. To avoid postoperative ischaemia of the lower leg, adequate perfusion must be guaranteed before sacrificing the peroneal vessels. Anatomical variations and peripheral arterial occlusive disease add to the risk of ischaemia. Various methods of evaluating the blood supply have been described. MATERIAL AND METHODS: Fifty-two consecutive cases of fibular flaps were evaluated to study the arterial blood supply of the lower extremity. For angiography, the right femoral artery was punctured using the Seldinger technique and a total of 20-25 ml contrast medium (Imeron 300) was infused and images required at a rate of 0.5/sec. RESULTS: A patent three-vessel supply to both feet could only be detected in 21 patients. Thirty-one angiograms revealed anatomic and/or arteriosclerotic alterations. Angiography provided accurate information in all patients and allowed successful fibular transfer in those patients who were found preoperatively to have regular conditions. CONCLUSION: Preoperative assessment of the blood supply of the lower extremity is important before fibular osteocutaneous free tissue transfer. We advocate angiography as interpretation is not examiner dependent.

Assessment of inferior alveolar and lingual nerve disturbances after dentoalveolar surgery, and of recovery of sensitivity.

In a follow-up of 1107 dentoalveolar operations in the postcanine region, 24 (2.2%) temporary sensitivity disturbances of the inferior alveolar nerve and 16 (1.4%) of the lingual nerve were found. Permanent disturbances were not present. Complete recovery had occurred by 6 months in all cases. The incidence of temporary sensitivity disturbances depended on the different surgical interventions performed. For evaluation and follow-up purposes, a computer-aided pain and thermal sensitivity (PATH) tester was used. By PATH testing, spontaneous recovery can already be ascertained at the third or fourth postoperative month.

Langerhans cell granulomatosis: a case report of polyostotic manifestation in the jaw.

We report the case of a 43-year-old woman who suffered from a polyostotic form of Langerhans cell granulomatosis (LCG) in the mandible and maxilla. The course of the disease was followed for more than 14 years. The disease's progression finally required subtotal resection of the mandible and reconstruction with a microvascular fibula graft. The literature is reviewed for diagnostic and treatment concepts based on the different stages of LCG.

In vitro cultured autologous pre-confluent oral keratinocytes for experimental prefabrication of oral mucosa.

The reconstruction of large defects after head and neck cancer resection often requires composite tissue transfer to replace a combination of bone, muscle and mucosa. Thus, tissue engineering techniques may be useful for oral mucosal reconstructive surgery to prefabricate mucosal tissue on the muscle flap in vivo, instead of using conventional skin-bearing composite flaps. The aim of this study was to investigate whether autogenous pre-confluent oral keratinocytes (PCOK) cultured in vitro can create mucosal coverage on muscle in vivo, in a single grafting procedure. In 30 Wistar rats, with a small piece of oral mucosa (2 mm x 5 mm), oral keratinocytes were isolated and then seeded on a hydrophilic PTFE membrane (n = 50) in serum-free culture condition. After 48 h, the membrane, together with the PCOK, was transplanted onto the gracilis muscle to fabricate a mucosal flap in vivo. The wound bed was closed primarily until the time of examination. Biopsies were carried out 1, 2, 3, and 4 weeks, respectively, after transplantation and were evaluated immunohistochemically (AE1/AE3 anti-pancytokeratin, cytokeratin 5/6, collagen IV, laminin, lectin-specific labeling of N-acetylglucosamine oligomeres of endothelial cells) with relation to the following criteria: (1) graft acceptance; (2) inflammatory signs; (3) structural changes and keratinocyte lining; (4) expression of basement membrane components; and (5) vascularization. Ninety-one percent of the grafts showed uniform epithelial layers. The mean number of reconstructed epithelial cell layers was 1.7, 2.0, 1.85 and 2.7 at 1, 2, 3 and 4 weeks, respectively after transplantation (P = 0.342). Collagen IV, laminin and lectin-specific capillaries developed between the neoepithelium and the underlying muscular layer. Only two specimens showed signs of infection 2 weeks after transplantation. In conclusion, this experiment demonstrated that PCOK grafts on muscle in vivo can achieve uniform multi-layered oral epithelial coverage in a short period of time. This technique may be a useful alternative tool for oropharyngeal reconstructive surgery and is also worth considering for further clinical studies.

Radiation-induced impairment of osseous healing with vascularized bone transfer: experimental model using a pedicled tibia flap in rat.

Aim of this study was to establish an appropriate animal model for investigating the healing of vascularized osseous transplants to irradiated recipient sites applying metabolic, vascular and immunologic experimental studies. In 20 Wistar rats (male, weight 300-500 g), a pedicled osseous tibia flap was raised and transferred to a subcutaneous pocket in the ipsilateral groin. The remaining tibia was stabilized with a monocortical titanium miniplate. To create a pre-irradiated transplant bed, the donor-area including the adjacent bone of the tibia was irradiated with a total dose of 50Gy (5 x 10 Gy) in 10 animals. The interval between irradiation and retransfer of the non-irradiated pedicled tibia flap was 4 weeks. Ten animals received no radiation. Evaluation of osseous healing and the success of the transferred flap were based on a clinical and quantitative histomorphometric assessment. Testing for significant differences was performed using the non-parametric Mann-Whitney U-test. The rate of complete osseous healing in the non-irradiated animals was 90%. In contrast there was no significant bone union observed in the group of the pedicled flaps grafted to the pre-irradiated (50Gy) recipient site (P = 0.001). Similarly bone formation in the transitional zone between bone graft and recipient bone was significantly lower in the preirradiated group (P < 0.001) (16.9 +/- 3%) in contrast to the non-irradiated transplant bed (47.9 +/- 6%).

Morbidity of harvesting of bone grafts from the iliac crest for preprosthetic augmentation procedures: a prospective study.

It has been the aim of the present prospective clinical study to assess the morbidity following the harvest of bone from the anterior and posterior ilium in elective preprosthetic augmentations. Fifty consecutive healthy patients (30 female, 20 male, mean age 52.5+/-9.3 years, range 31 years to 65 years) underwent augmentations of implant sites by iliac crest bone grafts. The bone harvest was carried out in 25 cases from the anterior and in 25 cases from the posterior ilium. The superficial sensory function of the skin was determined quantitatively preoperatively, 7 and 30 days after surgery with the 'Pain and Thermal Sensitivity' Test (PATH Test). On the same occasions subjective pain on a visual analogue scale (VAS) and gait disturbances were documented. In the PATH Test, for the innervation areas of the lateral femoral cutaneous nerve (LFCN) and the superior and middle cluneal nerves (SMCN) a significant impairment of the superficial sensory function could be found after 1 week and a significant tendency towards recovery after 1 month (warm stimulus(FCNpreop) 37.9+/-3.0 degrees C, warm stimulus(LFCNday7): 38.6+/-3.2 degrees C, warm stimulus(LFCNday30): 37.9+/-2.9 degrees C, P(LFCNwarmpreop/day7)=0.023,P(LFCNwarmpreop/day30) =0.886, warm stimulus(SMCNpreop): 36.1+/-2.4 degrees C, warm stimulus(SMCNday7): 36.6+/-2.3 degrees C, warm stimulus(SMCNday30): 36.3+/-4.0 degrees C,P(SMCNwarmpreop/day7) <0.0005,P(SMCNwarmpreop/day30) =0.086). Gait disturbances were seen in seven patients after anterior and in three patients after posterior bone harvest 7 days after surgery (P(gaitdisturbanceanterior/posterior)=0.123). After 1 month none of the patients of both groups showed gait disturbances any longer. The maximum subjective pain level was found on the second postoperative day in both groups. It was significantly higher for the anterior approach (VAS(anteriorday2) 7.0+/-1.5, VAS(posteriorday2) 5.5+/-1.8,P(VASanterior/posteriorday2) =0.004). At day 7 and at day 30, the pain levels did no longer differ significantly (VAS(anteriorday7) 3.7+/-1.4, VAS(posteriorday7) 3.2+/-1.6,P(VASanterior/posteriorday7) =0.165, VAS(anteriorday30) 1.4+/-0.7, VAS(posteriorday30) 1.4+/-0.8,P(VASanterior/posteriorday30) =0.724). Because of the lower morbidity of bone harvest from the posterior ilium in the early postoperative phase compared to the anterior approach it seems that it should be preferred in elective augmentation procedures.

Experimental model for transplantation of a modified free myocutaneous gracilis flap to an irradiated neck region in rats.

In 102 Wistar rats (male, weight 300-500 g), a modified free myocutaneous gracilis flap was obtained from the groin and transplanted to the neck. To create a pre-irradiated transplant bed, a local area of the neck was irradiated preoperatively with 30 Gy (fractionation: 3 x 10 Gy) in 30 animals, and with 50 Gy (fractionation: 5 x 10 Gy) in a further 30 animals. The interval between preoperative irradiation and transplantation was 4 weeks. Forty-two animals received no such preoperative radiation. The evaluation of healing and the success of the transplanted flap was based on a clinical assessment, carried out on postoperative days 1 7. Testing for significant differences was done nonparametrically using the Kruskal-Wallis test. The survival rate in the nonirradiated animals was 86%. In contrast, the healing of the free flaps in the pre-irradiated transplant bed was significantly lower (P=0.003) 76%, after irradiation with 30 Gy and 50% after 50 Gy. The significant difference (P=0.020) in survival rates after irradiation with 30 and 50 Gy was evidence for the dependence of successful healing on the preoperative radiation dose. Transplantation of the free myocutaneous gracilis flap to a previously irradiated transplant bed in the region of the neck is a suitable model for investigating the healing of free transplants to irradiated tissue. The success rate observed in non-irradiated transplant beds is comparable to that seen with other flap models in rats.

Histomorphometric analysis of irradiated recipient vessels and transplant vessels of free flaps in patients undergoing reconstruction after ablative surgery.

The aim of the study was to investigate, histomorphometrically, quantitative and qualitative changes in irradiated neck recipient vessels and transplant vessels used for microsurgical anastomoses in free flaps in patients undergoing preoperative radiotherapy and chemotherapy. In 55 patients receiving 42 radial forearm flaps, 6 latissimus dorsi flaps, 6 osteomyocutaneous fibula grafts and 1 lateral arm flap, a total of 220 vessels were obtained from neck recipient vessels and transplant vessels during anastomosis. Three groups were formed: Group 1 (16 patients) treated with no radiotherapy or chemotherapy; Group 2 (20 patients) treated with preoperative irradiation (40-50 Gy) and chemotherapy (800 mg/m2 5-FU and 20 mg/m2 cisplatin) 1.5 months prior to surgery; Group 3 (19 patients) treated with radiotherapy (60-70 Gy) (median interval 78.7 months; IQR 31.3 months) prior to surgery. From each of the 220 vessel specimens, 3 sections each were histomorphometrically investigated, both qualitatively and quantitatively. To evaluate these changes as a function of age, radiation dose and chemotherapy, a statistical analysis was performed using analysis of covariance and chi-square tests. In Group 3, qualitative changes (intima dehiscence, hyalinosis) were found in recipient arteries significantly more frequently (25%, P=0.009) than in Groups 1 and 2. For Group 3 recipient arteries, histomorphometry revealed a significant decrease in the ratio of media area/total vessel area (median 0.53, IQR 0.10) in comparison with Group 1 (P= 0.02) (median 0.60, IQR 0.29) and Group 2 (P=0.046) (median 0.59, IQR 0.10). No significant differences were found between the vessels of Groups 1 and 2 (P= 0.48). Age and chemotherapy did not appear to have a significant influence on vessel changes in this study.