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Dive into the research topics where Jeremy McMahon is active.

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Featured researches published by Jeremy McMahon.


British Journal of Oral & Maxillofacial Surgery | 2007

Use of Lugol's iodine in the resection of oral and oropharyngeal squamous cell carcinoma

Jeremy McMahon; J.C. Devine; James A. McCaul; Douglas McLellan; Adrian Farrow

We evaluated the use of Lugols iodine in achieving surgical margins free from dysplasia, carcinoma in situ, and invasive carcinoma by an observational study of two series of 50 consecutive patients having resection of oral and oropharyngeal squamous cell carcinoma (SCC) between November 2004 and March 2007. The standard group had resection of the primary tumour with a macroscopic 1cm margin and removal of adjacent visibly abnormal mucosa. The Lugols iodine group had identical treatment with resection of any adjacent mucosa that did not stain after the application of Lugols iodine (where this was feasible). In the standard group 16 patients (32%) had dysplasia, carcinoma in situ, or invasive SCC at a surgical margin. In the Lugols iodine group two patients (4%) had dysplasia or carcinoma in situ; none had invasive SCC. Lugols iodine is a simple, inexpensive, and apparently effective means of reducing the likelihood of unsatisfactory surgical margins in the resection of oral and oropharyngeal SCC.


British Journal of Oral & Maxillofacial Surgery | 2012

Influence of close resection margins on local recurrence and disease-specific survival in oral and oropharyngeal carcinoma

Ling Siew Wong; Jeremy McMahon; J.C. Devine; Douglas McLellan; Ewen Thompson; Adrian Farrow; K.F. Moos; Ashraf Ayoub

There is a lack of consistency among published reports in the definition of what constitutes close resection margins (1-5mm) in the surgical treatment of oral and oropharyngeal squamous cell carcinoma (SCC). Our aim was to define what would constitute close resection margins in predicting local recurrence and disease-specific survival. The study comprised 192 previously untreated patients with oral and oropharyngeal SCC who were recruited at the Southern General Hospital, Glasgow, from 2001 to 2007 with a minimum follow-up of 2 years. Resection was the primary treatment and the surgical margins were recorded for all patients. Statistical analyses were aided by the Statistical Package for the Social Sciences, version 15.0, and MedCalc software. The status of the surgical margins was evaluated using a receiver operating characteristic (ROC) curve to define the cut-off point. Coxs proportional hazard model was used to establish predictive factors for local recurrence and disease-specific survival. Of 192 patients, 23 (12%) had involved margins (<1.0mm), 107 (56%) had close margins (1.0-2.0mm (16.1%); 2.1-3.0mm (12%); 3.1-4.0mm (10.4%); 4.1-5.0mm (17.2%), and 62 (32.3%) had clear margins (>5mm). No predictive cut-off point was found that related close surgical margins to local recurrence. However, there was a significant adverse association between surgical margins ≤1.6mm and disease-specific survival. In recommending postoperative adjuvant treatment for oral and oropharyngeal SCC, we suggest that surgical margins within 2mm should be considered as the cut-off. However, other clinical and pathological prognostic factors should also be taken into consideration when recommending further treatment.


British Journal of Oral & Maxillofacial Surgery | 2010

Microbiology of odontogenic infections in deep neck spaces: a retrospective study.

Laith Al-Qamachi; Hiba Aga; Jeremy McMahon; Alistair Leanord; Nicholas Hammersley

The primary treatment of deep neck spaces odontogenic infection (DNSOI) with suppuration is surgery. Systemic antimicrobial therapy is an important adjunct. The initial prescription of antimicrobial therapy is empirical. Over the last decade we have observed a change in practice with the use of second-generation cephalosporins, in conjunction with metronidazole, replacing benzylpencillin and metronidazole. More recently evidence has emerged suggesting that antimicrobial resistance in nosocomial infections could be related to the widespread use of second and third-generation cephalosporins. This study was therefore initiated to determine whether this change in prescribing was justified. A total of 75 cases were retrospectively identified by scrutiny of the operating theatre data. These patients presented with significant DNSOI that required surgical drainage. Streptococcus milleri and mixed anaerobes were predominant. Only in three cases (4%) there were penicillin-resistant microorganisms. The substitution of benzylpenicillin for cefuroxime as an initial empiric therapy for DNSOI seems likely to have been equally efficacious in the large majority of cases. On the other hand, studies in preference of cephalosporins are based on in vitro trials. A multi-centre randomized controlled clinical trial directly comparing initial empiric second-generation cephalosporin therapy with benzylpenicillin in non-allergic patients is justified.


British Journal of Oral & Maxillofacial Surgery | 2015

Systemic inflammatory response and survival in patients undergoing curative resection of oral squamous cell carcinoma

O.M. Farhan-Alanie; Jeremy McMahon; Donald C. McMillan

Prognostic stratification in squamous cell carcinoma (SCC) of the head and neck has traditionally relied on the pathological staging of a tumour, but it is increasingly being recognised that host-related factors have an important role in the assessment of survival and recurrence. We aimed to evaluate the prognostic value of systemic inflammation scores including the modified Glasgow Prognostic Score (mGPS) in patients undergoing potentially curative resection for oral SCC. We retrospectively identified 178 patients who had curative operations for cancer of the oral cavity and soft palate between January 2006 and April 2011. Among the inclusion criteria were preoperative estimates of C-reactive protein and serum albumin. We analysed established pathological prognostic factors and scores for systemic inflammation as predictors of cancer-specific and overall survival. On univariate analysis, the mGPS was a significant predictor of both cancer-specific (p<0.001) and overall survival (p<0.001), and it remained an independent predictor of cancer-specific (HR: 2.12, 95% CI 1.49 to 3.00; p<0.001) and overall survival (HR: 1.69, 95% CI 1.23 to 2.31; p=0.001) on Cox regression analysis. The mGPS of activated systemic inflammation seems to be a powerful adverse prognostic indicator in resectable oral SCC.


Journal of Cranio-maxillofacial Surgery | 2012

Mandibular reconstruction in the rabbit using beta-tricalcium phosphate (β-TCP) scaffolding and recombinant bone morphogenetic protein 7 (rhBMP-7) – Histological, radiographic and mechanical evaluations

Kurt Busuttil Naudi; Ashraf Ayoub; Jeremy McMahon; Lucy Di Silvio; David F. Lappin; Keith D. Hunter; J.C. Barbenel

This investigation assesses the histological, radiographic and mechanical properties of regenerated bone in a unilateral critical-size osteoperiosteal mandibular continuity defect in the rabbit model, following the application of beta-tricalcium phosphate (β-TCP) scaffolding and recombinant human bone morphogenetic protein 7 (rhBMP-7). The study was carried out on nine cases; in six cases the critical-size defect was filled with rhBMP-7 in the β-TCP scaffolding, and in three cases the β-TCP was used alone. The cases were sacrificed 3 months post-operatively. Histologically the overall mean of the percentage of regenerated bone volume in the cases that received rhBMP-7 was 29.41% ± 6.25%, which was considerably greater than the 6.35% ± 3.08% in the cases treated with β-TCP alone. Mechanical testing of the cases treated with rhBMP-7 gave failure moments (55 mNm-2.040 Nm) that were consistently greater than those treated with β-TCP alone (0 mNm-48 mNm). In some cases the mechanical properties of the regenerated bone were comparable to those of untreated bone. RhBMP-7 in prefabricated β-TCP scaffolding appeared, radiographically and histologically, to be an effective method for bone regeneration in mandibular critical-size defects in the rabbit model. This points towards possible future clinical applications.


British Journal of Oral & Maxillofacial Surgery | 2013

Gastrostomy insertion in head and neck cancer patients: a 3 year review of insertion method and complication rates

P. McAllister; Colin MacIver; Craig Wales; Jeremy McMahon; J.C. Devine; G. McHattie; Boikanyo Makubate

Patients with head and neck cancer who have resection, radiotherapy, chemoradiotherapy, or a combination of these require nutritional support to be implemented before treatment, and this may involve insertion of a prophylactic gastrostomy feeding tube. The aim of this study was to compare the use and complication rates of percutaneous endoscopic gastrostomy (PEG) and radiologically inserted gastrostomy (RIG) in these patients at a tertiary referral centre. We retrospectively reviewed gastrostomy data forms completed by nutritional support nursing staff over a recent 34-month period, which included information on method of insertion, 30-day postoperative serious and minor complications, and mortality. A total of 110 patients had prophylactic insertion of a gastrostomy (21 PEG, 89 RIG) over the study period. In the first 12 months 13 (31%) PEG feeding tubes were placed but in the last 12 months none were inserted using an endoscopic approach. Serious complications occurred with 2 (10%) PEG and 12 (13%) RIG; the most common cause was accidental removal of the tube (n=13, 12%). Minor complications of peristomal infection, leakage, or blockage of the tube occurred in 6 (5%) gastrostomies. No patients died during the study period. In recent years, and in the absence of recommended guidelines, there has been an increase in the elective insertion of RIG in patients with head and neck cancer. Serious complications for both methods of insertion in this study are comparable with similar reports. However, with RIG there is a high rate of tubes becoming dislodged with the potential for serious consequences. The most appropriate method to insert a gastrostomy tube in patients with head and neck cancer remains unclear.


British Journal of Oral & Maxillofacial Surgery | 2010

Lip split and mandibulotomy modifications

P. Mehanna; J.C. Devine; Jeremy McMahon

ip split and mandibulotomy are reliable, well-established echniques used in the treatment of posteriorly placed oral haryngeal tumours. We describe simple modifications to hese techniques that improve aesthetic results, safety, and unctional outcome. The lip split procedure is an alternative to transcervical pproaches and provides access to oral pharyngeal tumours. roponents of the former feel that it gives good access with inimal detrimental aesthetic impact1 while others have tated that it causes more fistulas to form postoperatively, ore prominent scarring, notching of the vermillion, and mpaired mobility of the lip and chin.2,3 Modifications include a vertical linear incision through he lip and a curved incision through the chin (Fig. 1a and ). We propose a technique where a modified zigzag incision s made, the skin flap reflected, and the underlying muscle ivided in a linear and vertical fashion. As the incision and ivision of muscle are in different planes (Fig. 2) we feel that serious breakdown of the wound or formation of a fistula s less likely. The vertical incision through the muscle (as pposed to zigzag) ensures that the minimum length of musle is divided, which reduces the inherent amount of muscle rauma and long-term fibrosis. We think that this modificaion not only improves long-term aesthetic results, but also ids in postoperative function of the muscles and reduces the ossibility of wound breakdown. Although mandibulotomy can be done in a controlled anner we have found that the separation of the osteotomised egments can lead to an uncontrolled lingual mucosal tear,


International Journal of Oral and Maxillofacial Surgery | 2013

The clinical application of three-dimensional motion capture (4D): a novel approach to quantify the dynamics of facial animations

S. Shujaat; Balvinder Khambay; Xiangyang Ju; J.C. Devine; Jeremy McMahon; C. Wales; Ashraf Ayoub

The aim of this pilot study was to evaluate the feasibility of measuring the change in magnitude, speed, and motion similarity of facial animations in head and neck oncology patients, before and after lip split mandibulotomy. Seven subjects (four males, three females) aged 42-80 years were recruited. The subjects were asked to perform four facial animations (maximal smile, lip purse, cheek puff, and grimace) from rest to maximal position. The animations were captured using a Di4D motion capture system, which recorded 60 frames/s. Nine facial soft tissue landmarks were manually digitized on the first frame of the three-dimensional image of each animation by the same operator and were tracked automatically for the sequential frames. The intra-operator digitization error was within 0.4mm. Lip purse and maximal smile animations showed the least amount of change in magnitude (0.2mm) following surgery; speed difference was least for smile animation (-0.1mm/s). Motion similarity was found to be highest for lip purse animation (0.78). This pilot study confirmed that surgery did influence the dynamics of facial animations, and the Di4D capture system can be regarded as a feasible objective tool for assessing the impact of surgical interventions on facial soft tissue movements.


British Journal of Oral & Maxillofacial Surgery | 2010

Involved surgical margins in oral and oropharyngeal carcinoma—an anatomical problem?

Jeremy McMahon; J.C. Devine; Jonathan Hetherington; Gareth Bryson; Douglas McLellan; Colin MacIver; Evelyn Teasdale; Ravi Jampana

A previous audit conducted in the West of Scotland (WoS) suggested that anatomical factors accounted for a substantial proportion of invaded surgical margins after resection of an oral or oropharyngeal squamous cell carcinoma (SCC). Since then a number of technical improvements have taken place, the most important of which has been advanced digital imaging that has enabled better surgical planning. In this study we compare the incidence of involved surgical margins in a recent group with those found in the earlier audit. The earlier (WoS) group comprised a consecutive series of patient operated on for a primary SCC of the oral cavity or oropharynx between November 1999 and November 2001 (n=296). The later series comprised 178 patients operated on for oral or oropharyngeal SCC at the Southern General Hospital (SGH), Glasgow, between 2006 and 2009. A total of 245 patients in the WoS cohort had information available on the invasion of the margins of whom 68 (28%) had an invaded margin. Of 177 patients in the SGH group, 9 (5%) had an invaded margin (p=0.001). An anatomical approach to the resection of oral and oropharyngeal SCC is appropriate, as it results in a rate of invaded margins of less than 10% irrespective of size and site of the primary lesion.


British Journal of Oral & Maxillofacial Surgery | 2013

Patterns of local recurrence after primary resection of cancers that arise in the sinonasal region and the maxillary alveolus.

Jeremy McMahon; Ling Siew Wong; John A. Crowther; William Taylor; Joseph McManners; J.C. Devine; Craig Wales; Colin MacIver

Local recurrence remains the most important sign of relapse of disease after treatment of advanced cancer of the maxilla and sinonasal region. In this retrospective study we describe patterns of recurrence in a group of patients who had had open resection for cancer of the sinonasal region and posterior maxillary alveolus with curative intent. Casenotes and imaging studies were reviewed to find out the pattern of any relapse, with particular reference to local recurrence. The minimum follow-up period was 12 months. Of 50 patients a total of 16 developed recurrences, 11 of which were local. Of those 11, a total of 8 were in posterior and superior locations (the orbit, the infratemporal and pterygopalatine fossas, the traversing neurovascular canals of the body of the sphenoid to the cavernous sinus, the Gasserian ganglion, and the dura of the middle cranial fossa). Advanced cancer of the midface often equates with disease at the skull base. Treatment, including surgical tactics, should reflect that.

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J.C. Devine

Southern General Hospital

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Craig Wales

Southern General Hospital

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Colin MacIver

Southern General Hospital

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K.F. Moos

Glasgow Dental Hospital and School

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Ling Siew Wong

Glasgow Dental Hospital and School

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Nazlie Syyed

Southern General Hospital

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David Sutton

Bradford Royal Infirmary

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