The dentate adult human mandible: an anatomic basis for surgical decision making.

Mandibular resection for oral cancer assumes two major forms; segmental mandibulectomy for invasion and rim mandibulectomy for margins, the extent of removal being governed by the need to ensure oncologic safety. The purpose of our study was to establish basic principles for optimal resection design in various clinical situations. Thirty-six cadaveric, adult, dentate human mandibles were examined in detail and sectioned at six points each to study the cross- sectional anatomy at these sites. The majority of bones (32 of 36) revealed a conspicuous medullary core with a thin cortical rim 2 to 4 mm in thickness. The inferior alveolar nerve was found to course consistently within the anterior segment of the ramus and to dip significantly within the body (median height at molar area 7 mm). Accordingly, rim resections cannot include the entire medullary core and nerve as currently defined, whereas segmental resections can spare the posterior segment of the ramus in appropriate cases.

Laryngeal squamous carcinoma associated with longstanding localised amyloidosis. A case report.

An unusual case of squamous carcinoma arising in the background of longstanding localised tracheolaryngeal amyloidosis is reported and the relevant literature is briefly reviewed.

Primary tumours of the trachea: analysis of clinical features and treatment results.

Primary tracheal tumours are extremely rare and present with widely variant clinical and histological features. Treatment methods vary considerably, and few studies have sought to provide adequate guidelines. A retrospective analysis was carried out of all patients treated in our unit between 1965 and 1990. Our experience deals almost exclusively with high tracheal tumours involving the adjacent subglottic region. Squamous carcinoma (SCC) and adenoid cystic carcinoma (ACC) were the commonest subtypes, and presented with dyspnoea and hoarseness as the most frequent symptoms. ACCs occurred commonly in young individuals, presented insidiously, and ran a long, and often, unpredictable course. Endoscopic evaluation revealed the majority of the lesions to be bulky and obstructive in nature. Primary surgery with adjuvant radical radiotherapy, when indicated, appeared to provide optimal results. Debulking surgery followed by radiotherapy provided effective and lasting control in two cases of ACC. Other malignant subtypes behaved aggressively and progressed uncontrolled.

Scanning electron microscopic study of thrombus formation in an end-to-side anastomosis of the rat carotid artery.

The healing of conventional microvascular end-to-side anastomoses has been reported in several studies. The authors studied thrombus formation under scanning electron microscopy (SEM) in an end-to-side anastomotic model in rat carotid arteries. Twenty anastomoses were carried out with 10-0 nylon interrupted sutures. Thrombus formation was evaluated 30 min after clamp release. The findings indicated that the first 30 min are the most critical time for thrombus formation. Thrombi underwent partial lysis or embolization after this time, and gross intraluminal thrombi did not recur. Thrombus formation was studied at four different sites in the end-to-side anastomoses. The sites of needle holes and sutures were primary locations for thrombocyte adhesions and aggregations in normal, vascular anastomoses.

Oral cavity reconstruction: an objective assessment of function.

The prime objective of oral cavity reconstruction is restoration of function, which must be carefully studied while evaluating the success of any reconstructive endeavour. We devised a unique comprehensive test series for the purpose that is suitable for use in routine follow-ups, and capable of providing objective documentation. Functional assessment included evaluation of general health, food intake, oral competence, mastication, speech, swallowing, tongue mobility, and shoulder-neck function. Fifty patients who had surgery were analyzed and their functional scores compared with those of 10 normal volunteers. The extent of mandibular resection and the magnitude of soft tissue excision significantly affected overall scores of function. Oral competence, as reflected by the water holding test (WHT), was uniformly impaired in the 50 patients, and in dentate individuals, the quality of bolus provided good correlation with all other functional scores. Among reconstructive modalities employed here, the bi-paddled pectoralis major flap produced the best overall scores.

Composite resections for oral cancers--experience with 97 consecutive cases.

A retrospective study was carried out from the evaluable records of all (N = 97) patients who underwent composite resections in unit 'Head & Neck 'C' - Tata Memorial Hospital, over the years 1980, 81, 82, for a variety of oral cancers. The purpose of this study was to assess the true value of radical ablation. Tobacco addiction was observed in all patients with adequate documentation of habits. The vast majority of operations were performed for lesions of the buccal mucosa (N = 48) and lower alveolus (20); and squamous carcinoma was the predominant histologic type. Most patients presented with advanced T3 and T4 lesions. Nodal findings revealed a conspicuous disparity between clinical and pathological findings; and the final 'N' status was the most significant prognostic determinant. The results of reconstructive methods have also been reviewed. The majority of recurrences occurred within 12 months of surgery, local recurrence being commonest.

Complications of the pectoralis major myocutaneous flap in head and neck reconstruction.

A retrospective review of the complications in 211 patients undergoing pectoralis major myocutaneous flap reconstruction is presented. The flap was used for mucosal lining of the oral cavity or oropharynx in 109 patients, for pharyngoesophageal reconstruction in 44, for skin coverage in 47, and for other locations in 14 patients. Flap-related complications developed in 63% of the patients. These included flap necrosis, suture line dehiscence, fistula formation, infection, and hematoma. Analysis of risk factors for the development of flap complications showed the following factors to be significant: age over 70; female gender; nomographic overweight; albumin less than 4 g/dL; use of the flap in reconstruction of the oral cavity after major glossectomy; and presence of other systemic diseases. The median length of hospitalization for those developing complications was 33 days compared with 16 days for those who did not develop any complications. Thirty-five (26%) of the 135 patients developing complications required reoperation and only 2 among these required a second flap. Similarly, only 13 of the 61 patients who developed fistulas required surgical closure.