Online rapid sampling microdialysis (rsMD) using enzyme-based electroanalysis for dynamic detection of ischaemia during free flap reconstructive surgery.

We describe an enzyme-based electroanalysis system for real-time analysis of a clinical microdialysis sampling stream during surgery. Free flap tissue transfer is used widely in reconstructive surgery after resection of tumours or in other situations such as following major trauma. However, there is a risk of flap failure, due to thrombosis in the flap pedicle, leading to tissue ischaemia. Conventional clinical assessment is particularly difficult in such 'buried' flaps where access to the tissue is limited. Rapid sampling microdialysis (rsMD) is an enzyme-based electrochemical detection method, which is particularly suited to monitoring metabolism. This online flow injection system analyses a dialysate flow stream from an implanted microdialysis probe every 30 s for levels of glucose and lactate. Here, we report its first use in the monitoring of free flap reconstructive surgery, from flap detachment to re-vascularisation and overnight in the intensive care unit. The on-set of ischaemia by both arterial clamping and failure of venous drainage was seen as an increase in lactate and decrease in glucose levels. Glucose levels returned to normal within 10 min of successful arterial anastomosis, whilst lactate took longer to clear. The use of the lactate/glucose ratio provides a clear predictor of ischaemia on-set and subsequent recovery, as it is insensitive to changes in blood flow such as those caused by topical vasodilators, like papaverine. The use of storage tubing to preserve the time course of dialysate, when technical difficulties arise, until offline analysis can occur, is also shown. The potential use of rsMD in free flap surgery and tissue monitoring is highly promising.

Acute vasculitis resulting in free flap failure: the importance of early recognition and options for management.

Unusual or unexpected medical causes for free flap failure do occur but are uncommon. We present a rare case of a fibula free flap failure due to an acute vasculitis which was undiagnosed until after the flap had failed. In addition to two successful flap salvages and intravenous heparin, an epoprostenol infusion was commenced but a third salvage was not successful. The vasculitis resulted in marked blood vessel wall thickening, and cutaneous manifestations which presented as late signs. High peri-nuclear anti nuclear cytoplasmic antibody (pANCA) and myeloperoxidase (MOP) titres were subsequently found and histology from several blood vessels showed marked inflammation throughout the wall. A diagnosis of microscopic polyangiitis was made and high dose steroids were subsequently commenced. Interestingly, he had vasculitis several years previously treated with oral steroids but had been discharged from the rheumatology clinic. This rare case illustrates the potential hazards of free flap surgery in the vasculitides and discusses the warning signs and various management options to reduce the likelihood of flap failure in these patients.

Pentoxifylline and tocopherol in the management of patients with osteoradionecrosis, the Portsmouth experience.

Osteoradionecrosis of the jaw remains the most problematic consequence of radiotherapy for the management of head and neck cancer. Treatment is often complex and multimodal. New theories on its pathophysiology have allowed the development of potential treatment modalities, including the use of pentoxifylline and tocopherol. In this retrospective case series we examined the outcomes of patients with ORN prescribed pentoxifylline and tocopherol.

Herpes zoster associated with tooth resorption and periapical lesions.

A 72-year-old woman presented with multiple periapical lesions and resorption of teeth in a single quadrant 17 years after an attack of herpes zoster (shingles) of the maxillary division of the trigeminal nerve. It is possible that cases of tooth resorption that were previously classified as idiopathic may have a viral aetiology and we suggest that these patients should be asked about a previous attack of shingles.

A prospective study into the demographics and treatment of paediatric facial lacerations.

To evaluate the demographics and treatment of facial lacerations occurring in a paediatric patient cohort. We undertook a prospective study of 106 children who sustained a soft tissue facial injury and who presented to an Accident and Emergency department in a UK district general hospital supporting a population of 750,000. Approximately 31,000 are dependent children between the age of 0-12 years. Our results show that the majority of paediatric patients who sustained a facial laceration were male (62%). The frequency of this injury was greatest amongst males across all age groups. The majority of children above 3 years of age sustained their injury outdoors. The peak time for injury varied for different age groups. The 0-3 year olds sustained the highest incidence of injuries around 17:00 h. A bi-modal time pattern was seen in the 4-6 year age group, initially at 12:00 h with a second peak at 17:00 h. The most frequent aetiology was play. A significant finding was that 8% of the injuries that were managed resulted from a dog bite. Almost 50% of children above 4 years of age, who required primary closure of their laceration, were able to tolerate their treatment being performed under local anaesthesia. The pattern of facial lacerations in our study supports the results of previous studies. Our data has provided further insight into the presentation of these injuries. These studies are valuable in targeted injury prevention programmes aimed at potentially reducing the nature, incidence and severity of facial soft tissue trauma in children in the UK.

Occult stenosis of the common carotid artery complicating mandibular reconstruction with a fibular free flap.

An unsuspected severely stenosed common carotid artery that compromised a free flap for mandibular reconstruction is described. To our knowledge no one has advocated the assessment of the carotid tree before transfer of free tissue. We suggest that patients with several risk factors for peripheral vascular disease should have colour flow duplex imaging of the carotid system if transfer of free tissue is being considered.

Recurrent nodal metastases in the posterior triangle: implications for treatment of the atypical tumour.

We studied the incidence of recurrent nodal metastases in level V (posterior triangle) in patients who had previously had a staging or therapeutic dissection of the neck, with or without postoperative radiotherapy. Of 160 patients studied (177 neck dissections), 41 (26%) developed recurrent metastases in the neck. Four patients (3%) developed ipsilateral recurrent disease in level V. In these four patients, level III or IV lymph nodes were shown histologically to have extracapsular spread at the time of the original dissection. All four metastases were located at or just beyond the anatomical boundaries of the posterior triangle. None of the metastases at level V were from oral or oropharyngeal primary tumours.

Intraosseous vascular anomaly (haemangioma) of the zygoma.

Intraosseous vascular anomalies are rare, and although they have been described in the facial skeleton, those occurring in the zygomatic bone are extremely rare. We report the case of a 38-year-old woman who presented with a painless hard swelling in the left zygomatic prominence, which was diagnosed as a cavernous haemangioma after a bone biopsy. The further management of this lesion in discussed, with particular reference to surgical resection and reconstruction.

Does administration of isosorbide mononitrate affect cellular proliferation in oral squamous cell carcinoma? A prospective randomized clinical study.

PURPOSE: There has been much interest in the role that the signaling molecule nitric oxide (NO) plays in cancer. NO has both tumor-promoting and tumor-inhibiting effects that are dependent on its local tissue concentration. In animal studies, the administration of exogenous NO has reduced both tumor growth and dissemination, and in vitro NO administration causes death of oral cancer cell lines. We evaluated the oral administration of the NO donor drug isosorbide mononitrate (ISMO) on cellular proliferation in patients with oral squamous cell carcinoma. MATERIALS AND METHODS: A prospective randomized double-blind study was performed on 31 patients with biopsy-confirmed oral squamous cell carcinoma. Following incisional biopsy, patients were randomized to receive either ISMO (at a dose of 20 mg twice a day) or placebo tablets for 2 weeks before definitive resection. Cellular proliferation was compared between biopsy and resection specimens, using the immunohistochemical marker Ki-67. RESULTS: No statistical difference was found between Ki-67 indices in initial biopsy and resection specimens after ISMO (P =.23) or placebo (P =.5) administration. There were no obvious clinical changes seen in the tumor during the clinical trial as a result of ISMO administration. CONCLUSION: Although high concentrations of NO are cytotoxic, it is unlikely that administration of NO at an increased dose would be useful in the management of oral cancer because this would result in unacceptable systemic side effects. The possible manipulation of NO in oral cancer is discussed.

Skin necrosis of a pectoralis major myocutaneous flap, caused by methicillin-resistant Staphylococcus aureus.

A case of MRSA-induced skin necrosis of part of a pectoralis muscle flap is described. It highlights the importance of recognising potential MRSA infection following surgery and treating it early and aggressively.

A study to assess inducible nitric oxide synthase expression in oral lichen planus.

Nitric oxide (NO) has been implicated in a variety of diseases but has not been previously studied in oral lichen planus (OLP). Since OLP has a complex immunogenesis with abundant macrophage infiltration, this study determined by immunohistochemistry whether or not the expression of the inducible form of nitric oxide synthase (iNOS) was increased in this condition relative to normal mucosa. Thirty cases of OLP and 10 normal buccal mucosa biopsies were studied utilising primary antibodies to iNOS and CD68, a myelomonocytic marker. iNOS activity was additionally assessed using a [(14-)C]-labelled arginine to citrulline assay. CD68 expression was significantly increased in the cellular infiltrate of all 30 cases of OLP compared with normal mucosa (P<0.009). Although iNOS staining was seen in a minority of cells in nine cases, this was not statistically significant when compared with the absent staining in normal oral mucosa (P=0.26). Furthermore, the minimal iNOS activity found in OLP was similar to that in normal mucosa. We conclude that expression of iNOS by macrophages is downregulated in OLP and discuss the possible reasons for this finding.

The origin and role of erythema after carbon dioxide laser resurfacing. A clinical and histological study.

BACKGROUND: Transient erythema, which can last up to 3 months after carbon dioxide (CO2) laser skin resurfacing, is a usual side effect with pulsed or rapidly scanned CO2 lasers. OBJECTIVE: We evaluated the cause of erythema in the clinical setting and by histology in order to determine if and how we may decrease it, or even eliminate it. METHODS: Ten patients who underwent resurfacing were recruited to this study. Skin punch biopsies were taken at 0, 7, 21, and 90 days and analyzed by light microscopy. RESULTS: Erythema was noticed from about day 8, when the crusting on the skin surface was exfoliated. It reached its maximum intensity after 14 days, and had disappeared by 60-90 days. Histology showed an early inflammatory response, with an immature neopithelium, and rich vascularization. The normal epidermis had returned by 90 days, and during this period there was reduced optical scattering and absorption in melanin. CONCLUSION: Although the erythema is an unwanted side effect in the patient's eyes, it is to be expected and thus represents the effects of a combination of epidermal immaturity, reduced melanin absorption of light, reduced dermal optical scattering, and increased blood flow secondary to the surgically induced inflammatory response.

A clinical and histological comparison of flashscanning versus pulsed technology in carbon dioxide laser facial skin resurfacing.

BACKGROUND: Two different carbon dioxide (CO2) laser systems are currently in use for skin resurfacing. The vast majority of lasers use a pulsed beam, like the Coherent 5000C, but Sharplan uses scanning technology. OBJECTIVE: We describe a clinical and histological comparison of these two laser technologies in order to determine if there are differences in the outcome. METHODS: Twenty-two female patients underwent facial skin resurfacing using the Coherent 5000C UltraPulse CPG on one side of the face and the Sharplan Silk Touch on the contralateral side of the face. The clinical appearances were assessed periodically after treatment and punch biopsies were taken preoperatively and after 7, 21, and 90 days. Tissue was stained with Hematoxylin-Eosin, Masson Trichrom, and with the Verhoeff technique. Histological evaluation was performed on randomized samples taken from the same patient. Epidermis/dermis expression, collagen compaction, and elastin fiber quantity were compared to evaluate if any differences existed. RESULTS: The side treated by Coherent healed more rapidly and with excellent cosmesis. Greater erythema was observed on the Sharplan side, but had disappeared at the 90-day evaluation. At this time the quality of the results was similar with no particular difference between the sides treated by the Coherent or the Sharplan lasers. At the histological level, although tissue recovered faster on the Coherent side at the 7-day control, at 90 days the collagen was better compacted and organized on the Sharplan side. Similarly, the quantity of the elastin was significantly more enhanced on the Sharplan side. CONCLUSION: Irradiated laser energy density in relation to time, and the way that it is delivered, should play an important role at the moment of producing collagen shrinkage. The SilkTouch delivers laser energy more aggressively, thereby producing a more intense inflammatory tissue reaction, which results in slower recovery of tissue, compared with the Coherent CPG. More active enhancement of vascularization found in the Sharplan is likely to be the reason for a more effective collagen proliferation and compaction. These changes, together with the increase in elastin in the dermis, may produce longer lasting effects in skin resurfacing.

A prospective clinical evaluation of the longevity of resorbable sutures in oral mucosa.

A prospective, randomised and controlled clinical investigation was undertaken to evaluate the longevity of resorbable sutures in the oral environment. The sutures investigated were gut, polyglycolic acid and polyglactin 910, were of standard gauge and needle type, and were placed using a standard technique by trained clinicians. The sutures were monitored following apical surgery in 55 patients (110 sutures) and the median survival values were: gut - 4 days, polyglycolic acid - 15 days, polyglactin 910 - 28 days. These differences were highly statistically significant. A postal survey of 30 randomly selected oral and maxillofacial surgeons reveal most prefer to use resorbable sutures, with softgut the most popular choice. Most would like an ideal resorbable suture to last 5 to 14 days and in this respect none of the materials tested appears satisfactory.