Astrid L. Kruse

Factors influencing survival of free-flap in reconstruction for cancer of the head and neck: a literature review.

Microvascular free tissue transfer is a reliable technique for head and neck reconstruction with success rates of 90–99%. Currently, there is no consensus concerning antithrombotic agents, antibiotics, or monitoring techniques. Therefore, the aim of this study was to review current literature dealing with microvascular free‐tissue transfer and factors influencing the outcome. In addition to excellent microsurgical techniques, coupling devices are a promising new technique, but are not useful in all arteries. Antibiotics should be given in three doses, as a more lengthy dosage time seems to have no advantage. The risk for elderly patients can be best assessed by the American Society of Anesthesiologists (ASA) score, but early mobilization, including intense chest physiotherapy, is important. Anticoagulation can be considered in cases of small vessels, significant size mismatch, vein graft, or vessels of poor quality. Monitoring should be done hourly during the first 24 hours and then every 4 hours for the next 2 postoperative days.

Precision and accuracy of the 3dMD photogrammetric system in craniomaxillofacial application.

Background: In modern anthropometry of such complex structures as the face, three-dimensional scanning techniques have become more and more common. Before establishing them as a criterion standard, however, meticulous evaluation of their precision and accuracy under both ideal and clinical circumstances is essential. Potential sources of error need to be identified and addressed. Materials and Methods: Under ideal circumstances, a phantom is used to examine the precision and accuracy of the 3dMD system. A clinical setting is simulated by varying different parameters such as angle, distance, and system reregistration, as well as data evaluation under different levels of magnification. Results: The handling of the system was unproblematic in matters of data acquisition and data analysis. It was very reliable, with a mean global error of 0.2 mm (range, 0.1-0.5 mm) for mannequin head measurements. Neither the position of the head nor that of the camera influenced these parameters. New referencing of the system did not influence precision and accuracy. Conclusions: The precision and accuracy of the tested system are more than sufficient for clinical needs and greater than those of other methods, such as direct anthropometry and two-dimensional photography. The evaluated system can be recommended for evaluation and documentation of the facial surface and could offer new opportunities in reconstructive, orthognathic, and craniofacial surgery.

Classification of potential risk factors for trigeminocardiac reflex in craniomaxillofacial surgery.

PURPOSE Trigeminocardiac reflex (TCR) in craniomaxillofacial surgery can lead to severely life-threatening situations. At least mild forms are probably much more common than the existing surgical literature suggests. Therefore, the aim of this presentation of cases and literature review was to evaluate the predisposing factors leading to a classification of risk factors for potential TCR and to give information concerning preventive measures and management procedures. PATIENTS AND METHODS All surgery reports from the Department of Cranio-Maxillofacial and Oral Surgery in the University Hospital in Zurich between 2003 and 2008 were searched for severe intraoperative cardiovascular complications, and a literature review was performed for publications concerning asystole or bradycardia during maxillofacial surgical procedures. RESULTS Three incidents were revealed in which severe bradycardia--in 2 cases followed by asystole--had occurred. All incidents were successfully managed. CONCLUSION All craniomaxillofacial surgeons involved in orbital surgery in general and in the treatment of midface fractures, eyelid surgery, and orthognathic procedures in particular should be aware of the possibility of the TCR and should be familiar with its prevention and therapy.

Craniomaxillofacial fibrous dysplasia: A 10-year database 1996-2006

Fibrous dysplasia is a rare bone disease caused by an abnormal proliferation of fibrous tissue in bone. We retrospectively evaluated eight patients (female to male ratio 3:1, mean age 22.5 years, range 10-32) with a monostotic form who were treated between 1996 and 2006. Two each were affected in the lower jaw, the upper jaw, the midface, and the frontoparietal region. Most patients were referred because of a painless swelling. Biopsy specimens from two patients were examined, six patients had modelling osteotomies, two of whom had further operations because of progressive enlargement. There was no visual impairment or malignant transformation. Fibrous dysplasia should be treated as conservatively as possible, but in cases of functional disturbance that results from malignant transformation, or from the involvement of the optic foramen or the foramen magnum, an immediate operation is needed. Disfigurement can be another reason for operation. When there is a risk of malignant transformation, follow-up of patients is recommended.

Dental injuries in association with facial fractures

PURPOSE The aim of the study was to investigate the association between dental injuries and facial fractures. MATERIALS AND METHODS We performed a prospective study of 273 patients examined at a level 1 trauma center in Switzerland from September 2005 until August 2006 who had facial fractures. Medical history and clinical and radiologic examination findings were recorded to evaluate demographics, etiology, presentation, and type of facial fracture, as well as its relationship to dental injury site and type. RESULTS In 273 patients with dentition, we recorded 339 different facial fractures. Of these patients, 130 (47.5%) sustained a fracture in the non-tooth-bearing region, 44 (16%) had a fractured maxilla, and 65 (24%) had a fractured mandible. Among 224 patients with dentition who had a facial fracture in only 1 compartment, 140 injured teeth were found in 50 patients. Of 122 patients with an injury limited to the non-tooth-bearing facial skeleton, 12 sustained dental trauma (10%). In patients with fractures limited to the maxilla (n = 41), 6 patients had dental injuries (14.5%). In patients with fractures to the mandible (n = 61), 24 sustained dental injuries (39%). When we compared the type of tooth lesion and the location, simple crown fractures prevailed in both jaws. Patients with a fracture of the mandible were most likely to have a dental injury (39.3%). The highest incidence of dental lesions was found in the maxilla in combination with fractures of the lower jaw (39%). This incidence was even higher than the incidence of dental lesions in the lower jaw in combination with fractures of the mandible (24%). CONCLUSIONS Knowledge of the association of dental injuries and maxillofacial fractures is a basic tool for their prevention. Our study showed that in cases of trauma with mandibular fracture, the teeth in the upper jaw might be at higher risk than the teeth in the lower jaw. Further larger-scale studies on this topic could clarify this finding and may provide suggestions for the amelioration of safety devices (such as modified bicycle helmets).

Surgical Navigation in Craniomaxillofacial Surgery: Expensive Toy or Useful Tool? A Classification of Different Indications

The complex 3-dimensional (3D) anatomy and geometry of the human skull and face combined with the need for precise symmetry poses challenges for reconstructive surgery of the region. Therefore, and with the technical improvements during the past 10 years or so, surgical navigation has become an established technique in craniomaxillofacial surgery. 1-4 Many technical problems have been solved, and the accuracy of multiple strategies of imaging and registration has been proved. 5 However, the procedure of preparing a patient for navigation is still linked to extra effort for the patient and surgeon. Even noninvasive registration procedures, such as a splint fixed to the upper jaw, as described by Schramm et al, 6 require dental impressions and additional imaging with the splint in situ. Insecurity surrounds surgical navigation of the lower jaw with different techniques available, such as mounting a dynamic reference frame to the mandible 7-9 or retaining the mandible in a defined position against the maxilla. 7,10-15 Thus, the state of surgical navigation of the mandible has been deemed unsatisfactory to date. 16 The aim of the present study was to evaluate the feasibility and limitations of surgical navigation. In addition, we determined the time and effort of the surgical team in relation to the benefit.

Cervical metastases of squamous cell carcinoma of the maxilla: a retrospective study of 9 years

PurposeMetastases of squamous cell carcinoma of the tongue and the mouth floor have been well studied. Concerning maxilla squamous cell carcinomas, however, only a few studies have been performed. The question is whether a prophylactic neck dissection should be performed in these tumors.Patients and MaterialIn the Department of Craniomaxillofacial Surgery at the University Hospital of Zurich, 30 patients who had been treated for squamous cell carcinonoma of the maxilla were examined retrospectively. Special attention was paid to direct and late metastasis, survival rate, and treatment.ResultsOf the 59 patients with upper jaw carcinomas over a 9-year period, only about half (30 patients) had a squamous cell carcinoma of the upper jaw. Of those patients, 27% had an upper lesion on the right side, 33% on the left. Of the 11 patients (36.7%) presenting positive lymph nodes, 4 patients had direct positive lymph nodes while 7 patients had later positive lymph nodes; and 71.4% of the late metastasis appeared during the first year.ConclusionBecause of the 36.7% of patients presenting metastases in the cervical lymph nodes, elective neck treatment should be considered in cases even with a negative clinical examination.

Bone regeneration in the presence of a synthetic hydroxyapatite/silica oxide‐based and a xenogenic hydroxyapatite‐based bone substitute material

OBJECTIVES A comparison of synthetic hydroxyapatite/silica oxide, xenogenic hydroxyapatite-based bone substitute materials with empty control sites in terms of bone regeneration enhancement in a rabbit calvarial four non-critical-sized defect model. METHODS In each of six rabbits, four bicortical calvarial bone defects were generated. The following four treatment modalities were randomly allocated: (1) empty control site, (2) synthetic hydroxyapatite/silica oxide-based (HA/SiO) test granules, (3) xenogenic hydroxyapatite -based granules, (4) synthetic hydroxyapatite/silica oxide -based (HA/SiO) test two granules. The results of the latter granules have not been reported due to their size being three times bigger than the other two granule types. After 4 weeks, the animals were sacrificed and un-decalcified sections were obtained for histological analyses. For statistical analysis, the Kruskal-Wallis test was applied (P<0.05). RESULTS Histomorphometric analysis showed an average area fraction of newly formed bone of 12.32±10.36% for the empty control, 17.47±6.42% for the xenogenic hydroxyapatite -based granules group, and 21.2±5.32% for the group treated with synthetic hydroxyapatite/silica oxide -based granules. Based on the middle section, newly formed bone bridged the defect to 38.33±37.55% in the empty control group, 54.33±22.12% in the xenogenic hydroxyapatite -based granules group, and to 79±13.31% in the synthetic hydroxyapatite/silica oxide -based granules group. The bone-to-bone substitute contact was 46.38±18.98% for the xenogenic and 59.86±14.92% for the synthetic hydroxyapatite/silica oxide-based granules group. No significant difference in terms of bone formation and defect bridging could be detected between the two bone substitute materials or the empty defect. CONCLUSION There is evidence that the synthetic hydroxyapatite/silica oxide granules provide comparable results with a standard xenogenic bovine mineral in terms of bone formation and defect bridging in non-critical size defects.

Head and Neck Cancer in the Elderly: A Retrospective Study over 10 Years (1999 - 2008)

IntroductionTreatment of elderly patients is in many ways different from that for younger ones. The aim of the present study was to identify the particular characteristics and needs of elderly patients suffering from head and neck cancer. From these patterns, considerations for this special group can be deduced.Patients and MaterialThe subjects for this study consisted of 376 patients suffering from head and neck cancer that were treated between 1999 and 2008, 99 (26.3.%) of whom were older than 70 years and were evaluated retrospectively concerning smoking/alcohol abuse, ASA status, kind of malignant neoplasm, localization and treatment.ResultsThe male-female ratio was 53:46, and mean age, 79 years (71 - 98). Out of 95 patients with a squamous cell carcinoma, 4 patients had a verrucous form. Out of 99 patients, 26 had a maxillary carcinoma and 12 patients had experienced previous non-head-and-neck cancer. An ASA score of 2 or 3 was found in 86 of the patients.ConclusionThe group of patients with head and neck cancer who were older than 70 years was characterized by a higher portion of female patients, a higher number of maxillary carcinomas, and a higher prevalence of previous second cancer.Making decisions in cancer therapy for elderly patients is challenging. Patients suffering from operable head and neck cancer should be treated with curative intent and with regard to quality of life if a careful assessment of comorbidities is performed preoperatively.

Oral carcinoma after hematopoietic stem cell transplantation – a new classification based on a literature review over 30 years

BackgroundPatients undergoing hematopoietic stem cell transplantation (HSCT) have a higher risk of developing secondary solid tumors, in particular squamous cell carcinoma, because of several risk factors, including full-body irradiation (TBI), chemotherapy, and chronic graft versus host disease (GVHD). Based on the review presented here, a classification of oral changes is suggested in order to provide a tool to detect high-risk patients.Methods and ResultsThe literature over the last 30 years was reviewed for development of malignoma of the oral cavity after HSCT. Overall, 64 cases were found. In 16 out of 30 cases, the tongue was the primary location, followed by the salivary gland (10 out of 30); 56.4% appeared in a latency time of 5 to 9 years after HSCT. In 76.6%, GVHD was noticed before the occurrence of oral malignancy. Premalignant changes of the oral mucosa were mucositis, xerostomia, and lichenoid changes, developing into erosive form.ConclusionAll physicians involved in the treatment of post-HSCT patients should be aware of the increased risk, even after 5 years from the development of oral malignancy, in particular when oral graft versus host changes are visible. In order to develop evidence based management, screening and offer adequate therapy as early as possible in this patient group, multicenter studies, involving oncologists and head and neck surgeons, should be established.