Sudden transient complete loss of vision caused by nose blowing after a fracture of the orbital floor.

A 52-year-old man was being attended to in a hospital for a fracture of the right zygoma and orbital floor, after being struck on the right upper face. After blowing his nose, he immediately lost vision in the right eye, and an urgent CT scan showed extensive retrobulbar air. Vision was regained within an hour. The management of this rare condition is discussed.

Simultaneous spectrophotometric determination of salbutamol and bromhexine in tablets.

Typical anti-mucolytic drugs called salbutamol hydrochloride and bromhexine sulfate encountered in tablets were determined simultaneously either by using linear regression at zero-crossing wavelengths of the first derivation of UV-spectra or by application of multiple linear partial least squares regression method. The results obtained by the two proposed mathematical methods were compared with those obtained by the HPLC technique.

Does expression of inducible nitric oxide synthase correlate with severity of oral epithelial dysplasia?

The small molecule nitric oxide (NO) has generated an exponential amount of research since its discovery as a biological messenger in 1987. It has a vast number of actions, many of which are poorly understood. It has been studied in a variety of human cancers and has been implicated both in tumour promotion and inhibition. Although NO is produced by three distinct isoforms of the enzyme nitric oxide synthase (NOS), most cancer research is directed towards the calcium-independent form, iNOS which following induction, produces much higher quantities of NO than the other two. In this study the expression of iNOS is assessed by immunohistochemistry in 26 cases of oral epithelial dysplasia ranging in severity from mild to severe. iNOS staining was found in all 26 cases of dysplasia with the degree of staining correlating to the severity of dysplasia (p < 0.001). There was no iNOS staining seen in adjacent normal epithelium. The possible role of iNOS in the complex transformation from dysplasia to invasive oral cancer and the clinical applications are discussed.

Repair of the radial forearm flap donor site with a full-thickness graft.

A method of closing the radial forearm free flap donor site defect with a defatted, full-thickness skin graft is described. Its advantages of improved patient mobilization, protection of tendons, and cosmesis are discussed with reference to 16 consecutive patients treated over a period of 1 year.

Use of audiotaped patient consultations in a head and neck oncology clinic and survey of patient attitudes to this facility.

The overall quality and delivery of patient care is becoming increasingly important, especially in those diagnosed with cancer. Multidisciplinary clinics are a valuable adjunct to this, but patients may not fully understand or comprehend all that is said to them. The use of audiotaping consultations has been studied in some settings, but not in head and neck cancer clinics. We report on a series of 50 consecutive head and neck patients to determine their views on the value of this facility. Thirty-nine patients (78 per cent) utilized the opportunity, of which 36 patients (92 per cent) found it beneficial. Over three quarters of the patients who used the facility thought that medical staff could benefit and learn from the tape recording. We recommend that audiotaping becomes a standard part of the multidisciplinary head and neck oncology clinic, helping to improve the overall quality of patient care.

A clinical and biomechanical assessment of the Hall surgical miniplate system.

The Hall surgical miniplating system has been evaluated for use in maxillofacial trauma and orthognathic surgery. The biomechanical characteristics of the plates have been examined and experience gained, using 53 plates, in 25 patients is presented. The feature which distinguishes these plates is the narrow bridge between paired screw platforms. The specially designed screwdriver has a splined head which allows screw transfer to be carried out as a one-handed procedure. The plates show considerable advantages over existing small plate systems in their size, malleability and consequent ease of handling.

Infantile fibromatosis with involvement of the mandible.

Two unusual cases of infantile fibromatosis involving the mandible occurring in 2-year-old children are described. These tumours, though initially highly aggressive, underwent spontaneous regression in the absence of definitive treatment.

Controversies in third molar surgery--the national view on review strategies.

A national survey was conducted to establish the current practice of postoperative review of third molar surgery by the 255 fellows of the British Association of Oral and Maxillofacial Surgeons. Of the 216 complete responses, 134 say that they routinely reviewed all patients, while 67 did not. A further 15 fellows (7%) are currently considering their practice. Five (2%) stated that routine review should be compulsory and failure to do so was medically negligent. We conclude that a policy of selective rather than routine review is safe for most patients, but if a patient is under age, mentally retarded, taking psychoactive drugs, or has any other associated condition, then routine follow-up should be undertaken.

Emerging role of nitric oxide in cancer.

The small molecule nitric oxide has generated an exponential amount of research since its identification as a biological messenger in 1987. It is a free radical, the actions of which are diverse, and many are still poorly understood. An area of great interest is the role of nitric oxide in the growth and metastasis of solid tumours, where it seems to have a complex action including both inhibitory and tumour-promoting activity. Over 28,000 research papers have been written on nitric oxide, with only a minority concentrating on the head and neck. In this review, we give a brief history of this fascinating molecule, concentrating on its possible interest to oral and maxillofacial surgeons.

Expression of nitric oxide synthase in pleomorphic adenomas of the parotid.

The actions of nitric oxide (NO) in the pathology of solid tumours are complicated and many are poorly understood because NO has both inhibitory and tumour-promoting activities. In the current study we aimed to find out immunohistochemically whether the expression of both the inducible (iNOS) and endothelial (eNOS) forms of the enzyme nitric oxide synthase (NOS) were changed in pleomorphic adenomas of the parotid compared with normal salivary tissue. There was a significant difference in staining for iNOS between the tumour and normal salivary tissue, with tumour epithelial cells being stained in 29 cases of the 30 cases studied (P< 0.0001). The luminal cells of the salivary ducts also stained, but not the normal salivary tissue. Immunohistochemistry for the eNOS isoenzyme showed moderate staining of the tumour epithelium in only three specimens. There was also mild staining in the salivary duct cells of the normal glandular tissue and in endothelium of blood vessels in both tumour and normal glandular tissue in the same 29 cases.

Correlation between type II nitric oxide synthase and p53 expression in oral squamous cell carcinoma.

Prolonged nitric oxide (NO) production by the enzyme type II nitric oxide synthase (NOS2) has been implicated in angiogenesis and metastasis of human cancers. In animal models, wild-type p53 (but not mutant) protein results in down-regulation of NOS2 expression, which reduces both tumour growth and dissemination. In the current study, we aimed to find out whether a correlation was present in oral squamous cell carcinoma. Fifty-six cases of squamous cell carcinoma were assessed immunohistochemically using antibodies to NOS2 and p53 (clone DO-7). We also confirmed NOS2 protein expression in selected cases using immunoblotting. The results were correlated with clinicopathological findings. Statistical analysis showed a significant relationship between p53 and NOS2 expression (P= 0.001). No relationship was found between size of tumour or histological degree of differentiation, and NOS2 expression in the primary tumour.

Management of palatally impacted canines: the findings of a collaborative study.

The impacted palatal canine requires a combination of both surgical and orthodontic management. Two types of approach are commonly used: simple exposure, or exposure with bracketing at the time of surgery. In this study 104 consecutively treated patients with palatally impacted canines were examined at two centres, one at which the ectopic tooth was surgically exposed alone and the other where an orthodontic bracket was bonded to facilitate early traction, and the flap replaced. The aim was to compare the outcome and complication rate for each type of procedure. In 30.7 per cent of all cases exposed and bracketed a second surgical intervention was required, compared with 15.3 per cent in the simple exposure group. Bracketing, though effective, is a more costly and time-consuming procedure, and it is suggested that simple exposure provides an equally efficient and predictable method of managing the palatally impacted canine with obvious clinical and financial benefits. The long-term periodontal status of the teeth which have been exposed in these two ways, however, needs further investigation.

Indications for third molar surgery.

Recent reports have suggested that the practice of prophylactic lower third molar surgery is widespread, possibly account for up to 50% of all patients treated. An objective effort to refute the findings of the previously published data was undertaken by the Maxillofacial Unit of a large district general hospital trust. A prospective study of 454 consecutive patients referred for third molar surgery demonstrated that in 96% of the patients, at least one nationally defined criteria for surgery was present. A concurrent retrospective audit of patients already on the waiting list for surgery identified that 97% had at least one valid criterion for surgery. Of those patients who presented with unilateral symptoms, over half had only the troublesome side removed. Only 11 out of 454 patients were accepted for treatment without a defined criterion, all of whom had partially erupted teeth. The evidence presented in the current study is compared with previously reported data and possible reasons for the variance are discussed.

Are myoepithelial cells responsible for the widespread expression of inducible nitric oxide synthase in pleomorphic adenoma? An immunohistochemical study.

Many of the actions of nitric oxide (NO) are still poorly understood. Recently, it has been shown that the inducible isoform of the enzyme nitric oxide synthase, iNOS, is expressed in both salivary ducts and pleomorphic adenoma. The current immunohistochemistry study determined whether or not this distribution correlated with smooth muscle actin (SMA) expression, thereby suggesting the expression by myoepithelial cells in both sites. Twenty cases of histologically confirmed pleomorphic adenoma, the sections of which contained adjacent normal salivary gland tissue, were stained for iNOS and smooth muscle actin (clone 1A4). The salivary ducts of all cases were stained intensely by both antibodies, with smooth muscle actin staining also being noted around acini in the normal gland parenchyma. Moderate or heavy staining for iNOS was found in all specimens of pleomorphic adenoma, with smooth muscle actin being distributed in a similar manner in 19 cases. Smooth muscle actin, but not iNOS, was also noted in blood vessels of both normal glands and tumours. The correlation between iNOS and SMA in pleomorphic adenoma was significant (P<0.001). The presence of iNOS in normal salivary ducts and pleomorphic adenoma is most likely due to expression by myoepithelial cells.

Type II nitric oxide synthase (NOS2) expression correlates with lymph node status in oral squamous cell carcinoma.

In tumour biology, nitric oxide (NO) has a complex array of concentration-dependent actions, including both inhibitory and promoting effects. It is thought that the levels of NO found in many human cancers lead to enhanced angiogenesis and tumour dissemination. In the current study, we assessed the immunohistochemical expression of the enzyme type II nitric oxide synthase (NOS2) in 41 cases of oral squamous cell carcinoma and correlated the findings with lymph node status. A significant relationship was found between NOS2 expression and lymph node metastasis (P<0.0002). Furthermore, lymph node metastasis correlated with the degree and intensity of staining seen (P<0.001). No correlation was found between the size of the primary tumour, degree of tumour differentiation or smoking status and NOS2 staining. Western blotting confirmed NOS2 protein expression in select cases. As with many other human tumours, NOS2 is not a ubiquitous finding in oral cancer. Its expression may be of value in assessing lymph node status prior to surgery, and it represents a target for possible therapeutic manipulation.

Does type II nitric oxide synthase expression correlate with cellular proliferation in oral squamous cell carcinoma and dysplasia?

BACKGROUND: Nitric oxide (NO) has been implicated both in tumor progression and inhibition. This study investigated whether type II nitric oxide synthase (NOS2) expression correlated with cell proliferation in oral squamous cell carcinoma (OSCC) and dysplasia. METHODS: Paraffin-embedded tissue samples of normal oral mucosa, OSCC, and dysplasia were assessed immunohistochemically using monoclonal antibodies to NOS2 and Ki-67 antigen. We used Western blotting to confirm NOS2 antibody specificity and protein expression in select cases. RESULTS: NOS2 staining was increased in OSCC relative to normal oral mucosa, in which no expression was found. Both NOS2 expression and Ki-67 indices independently correlated with grade of dysplasia (p < .001) but not with the degree of tumor differentiation. A positive correlation was found between NOS2 expression and Ki-67 in cases of mild and moderate dysplasia (p < .001), but not in severe dysplasia and OSCC. CONCLUSIONS: No correlation exists between Ki-67 and NOS2 expression in severe dysplasia and OSCC. The findings suggest that the level of NO produced by NOS2 is insufficient to affect cellular proliferation in these conditions. The mechanism of NOS2 activation and the consequences of its expression remain to be fully explained.