Inflammatory conditions of the neck

Parapharyngeal and retropharyngeal abscess formation has been covered earlier in this chapter.

Ludwig angina

Ludwig described a clinical entity characterised by a brawny swelling of the submandibular region combined with inflammatory oedema of the mouth. It is these combined cervical and intraoral signs that constitute the characteristic feature of the lesion, as well as the putrid halitosis that is always present. The infection is often caused by a virulent streptococcal infection associated with anaerobic organisms and sometimes with other lesions of the floor of the mouth such as carcinoma. The infec­tion encompasses both sides of the mylohyoid muscle causing oedema and inflammation such that the tongue may be displaced upwards and backwards giving rise initially to dys­phagia and subsequently to potential obstruction of the airway.

Clinical cause

Unless the infection is controlled cellulitis may extend down the neck beneath the deep fascial layers to involve the larynx causing glottic oedema.

Treatment

Antibiotic therapy should be instituted as soon as possible using intravenous broad-spectrum antibiotics such as amoxycillin or cefuroxime combined with metronidazole to combat the anaerobes. In advanced cases where the swelling does not subside rapidly with such treatment, a curved submental incision may be used to drain both submandibular triangles. The mylohyoid muscle may be incised to decompress the floor of the mouth. Simple but generous corrugated drains may be placed in the wound which is then lightly sutured. This operation may be conducted under local anaesthesia and on rare occasions an additional tracheostomy may be necessary.

Cervical lymphadenitis (Table 43.14)

There are approximately 800 lymph nodes in the body; no fewer than 300 of them lie in the neck. Inflammation of the lymph nodes of the neck is exceedingly common. Infection occurs from the oral and nasal cavities, the pharynx, larynx, ear, scalp and face. The source of the infection must be sought systematically.

Acute lymphadenitis

The affected lymph nodes are enlarged and tender, and there may be varying degrees of general constitutional disturbance of the patient with pyrexia, anorexia and general malaise. The treatment in the first instance is directed to the primary focus of infection, for example tonsillitis or a dental abscess. If, despite antibiotic therapy, the pain continues or abscess formation occurs in the lymph nodes, parapharyngeal or retropharyngeal space then surgical drainage may be required.

Chronic lymphadenitis

Chronic painless lymphadenopathy may be either tuberculus, in children or young adults, or due to secondary malig­nant metastases most commonly from a squamous carcinoma in older people. Lymphoma also commonly presents in cer­vical nodes in young adults. Careful inspection of the upper airways and food passages is essential to exclude primary malignancy of the nasopharynx, tonsil, tongue base, piriform fossa or larynx. Fine needle aspiration of enlarged cervical lymph nodes is preferable to any form of open biopsy.

Tuberculous adenitis

Tuberculosis (TB) remains a problem throughout the world and is still a common cause of cervical lymphadenopathy. The condition most commonly affects children or young adults, but can occur at any age. The deep upper cervical nodes are most commonly affected, but there may be a widespread cervical lymphadenitis and the matching together of a substantial number of lymph nodes may be evident.

In most instances the tubercular bacilli gain entrance through the tonsil of the corresponding side of the lym­phadenopathy. Both bovine and human TB may be respon­sible. In approximately 80 per cent of cases the tuberculous process is limited to the clinically affected group of lymph nodes but a primary focus in the lungs must always be sus­pected and investigated. As renal and pulmonary TB occasionally coexist, the urine should be examined carefully. Rarely, the patient may develop a natural resistance to the infection and the nodes may be detected at a later date as evidenced by calcification on an X-ray. This can also be seen after appropriate general treatment of tuberculous adenitis. If treatment is not instituted, the caseated node may liquefy and break down with the formation of a cold abscess in the neck (Fig. 43.60). The pus is first confined by the deep cervical fascia but after weeks or months this may become eroded at one point and the pus flows through the small opening into the space beneath the superficial fascia. The process has now reached the well-known stage of a ‘collar stud’ abscess. The superficial abscess enlarges steadily and, unless suitable treatment is adopted, the skin will soon become reddened over the centre of the fluctuating swelling and before long a discharging sinus occurs in the neck.

Treatment. The patient should be treated by appropriate chemotherapy, as confirmed by assessment of abscess contents for sensitivities to the antituberculous drugs. If an abscess fails to resolve despite appropriate chemotherapy and general mea­sures, occasionally excision of the abscess and its surrounding fibrous capsule is necessary together with the relevant lymph nodes. If there is active TB of another system, for example pulmonary, then removal of tuberculosis lymph nodes in the neck is inappropriate. The nodes are commonly related to the internal jugular vein, common carotid and vagus nerve, and they may be associated with a great deal of surrounding fibrosis. Surgery can be difficult and a portion of the internal jugular vein may require excision with considerable care to avoid damage to the vagus or the cervical sympathetic trunk. A good view and access should be obtained at all times during this surgery and the sternocleidomastoid muscle divided to facilitate access, particularly if the disease is adjacent to the spinal accessory nerve or the hypoglossal nerve. The resected nodes should be sent for both pathological and micro­biological analysis.

Primary tumours of the neck

Neurogenous tumours

Chemodectoma (carotid body tumour). This is a rare tumour but there is a higher incidence in areas where people live at high altitudes, for example in Peru and Mexico where increas­ed numbers have been reported as a consequence of chronic hypoxia leading to carotid body hyperplasia. The tumours most commonly present in the fifth decade and approximately 10 per cent of patients have a family history. There is an association with phaeochromocytoma. The tumours arise from the chemoreceptor cells on the medial side of the carotid bulb and at this point the tumour is adherent to the carotid wall (Fig. 43.61). The cells of the chemodectoma are not hor­monally active and the tumours are usually benign with only a few proven metastases in a small number of cases.

Clinical features.

The patients often present with a long history of several years of a slowly enlarging painless lump at the carotid bifurcation. About one-third of patients present with a pharyngeal mass pushing the tonsil medially and anteriorly. The mass is firm, rubbery, pulsatile and is mobile from side to side but not up and down, and can sometimes be emptied by firm pressure, after which it will slowly refill in a pulsatile manner. A bruit may also be present. Swellings in the parapharyngeal space which often displace the tonsil medially should not be biopsied from within the mouth.

Investigations. When a chemodectoma is suspected a duplex study and, if indicated, a carotid angiogram should be carried out to demonstrate the carotid bifurcation which is usually splayed and a blush which outlines the normal tumour vessels. This tumour must not be biopsied and fine needle aspiration is also contraindicated.

Treatment. Because these tumours rarely metastasise and their overall rate of growth is slow, the need for surgical removal must be considered carefully as complications of surgery are potentially serious. The operation is best avoided in elderly patients. Radiotherapy has no effect. In some cases it may be possible to dissect the tumour away from the carotid bifurcation, but at times when the tumour is barge it may not be separable from the vessels and resection will be necessary such that all appropriate facilities should be avail­able to establish a bypass whilst a vein autograft is inserted to restore arterial continuity in the carotid system.

Vagal body tumours. Vagal paragangliomas arise from nests of paraganglionic tissue of the vagus nerve just below the base of the skull near the jugular foramen. They may also be found at various sites along the nerve down to the level of the carotid artery bifurcation.

Clinical features.

They also present as slowly growing and painless masses in the anterolateral aspect of the neck, and may also have a long history commonly of 2—3 years before diagnosis. Diagnosis is confirmed by CT and MRI scanning and additional arteriography if necessary. They may spread into the cranial cavity and surgery may be required. Peripheral nerve tumours. Schwannomas are solitary and encapsulated tumours attached to or surrounded by a nerve. Paralysis of the associated nerve is unusual. The vagus nerve is the commonest site for these tumours within the neck. Neurofibromas also arise from the Schwann cell and may be part of von Recklinghausen syndrome of multiple neuro­fibromatosis. Multiple neurofibromatosis is an autosomal dominant hereditary disease and the neurofibromata may be present at birth and often multiple. These lesions may occur in the neck and in about 10 per cent of these tumours malignant change occurs, although they usually enlarge slowly over a period of many years and the painless neck mass is the only sign. As with the lesions above, diagnosis requires angiography and scanning to differentiate them from other parapharyngeal tumours, but on occasions the diagnosis must wait until excision.

Secondary carcinoma of the neck

Secondary carcinomatous infiltration of the cervical lymph nodes is a common occurrence from important primary sites in the head and neck. These are nasopharynx, tonsil, tongue, piriform fossa and supraglottic larynx. All of these areas must be carefully assessed to search for the primary growth before considering biopsy or any surgery on the neck. Investigation is further assisted by fine needle aspirate of the neck node.

Management

The management of the involved cervical lymph nodes depends on the overall treatment regime to be given to the patient.

  If surgery is being used to treat the primary disease and the cervical nodes are palpable, and in excess of 3 cm, they may be excised en bloc with the primary lesion.

  If radiotherapy is used initially, as is always the case in carcinoma of the nasopharynx, then radiotherapy may also be given to the neck nodes whatever their stage. In the case of tongue, pharynx or larynx, however, if the node exceeds 3 cm in diameter then surgery may be necessary for the neck nodes even if the primary is treated by radiotherapy.

If radiotherapy is used initially, as is always the case in carcinoma of the nasopharynx, then radiography may also be given to the neck nodes, whatever their stage. In the case of the tongues, pharynx or larynx however, if the node exceeds 3 cm in diameter then surgery may be necessary for the neck nodes, even if the primary is treated by radiotherapy. If radiotherapy is used initially with resolu­tion of the primary but there is subsequent residual or recurrent nodal disease then this situation will require cervical lymph node dissection.

Types of neck dissection

  Classical radical neck dissection (Crile) the classic operation involves resection of the cervical lymphatics, the lymph nodes and those structures closely associated such as the internal jugular vein, the accessory nerve, the submandibular gland and the sternomastoid muscle. These structures are all removed en bloc and in continuity with the primary disease if possible. The main disability that follows the operation is the drooping of the shoulder due to paralysis of the trapezius muscle as a consequence of excision of the accessory nerve.

  Modified radical neck dissection in selected cases one or more of the three following structures are preserved, the accessory nerve, the sternocleidomastoid muscle or the internal jugular vein, but otherwise all major lymph node groups and lymphatics are excised. Whichever structures are preserved at this dissection should be clearly noted.

  Selective neck dissection in this type of dissection one or more of the major lymph node groups is preserved along with sternomastoid muscle, accessory nerve and internal jugular vein. Under these circumstances the exact groups of nodes excised must be documented.