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Radiologic studies

Magnetic resonance imaging (MRI) can establish whether the superficial or deep lobes are involved, whether suspicious lymphadenopathy is present, or whether there is invasion of the facial nerve. It may also help to differentiate individual histologic lesions.

Computed tomography (CT) scans discern many of the same structural details but are not nearly as successful in differentiating histologic lesions.

Ultrasound can localize the lesion to the superficial or deep lobe but otherwise adds little information.

Plain radiographs or sialograms may be useful for imaging stones.

Invasive tests

Fine-needle aspiration has a good accuracy rate (87%) and a low risk of spreading malignant cells. It may be helpful when planning the extent of surgery needed.

Core -needle biopsy or open biopsy carries the risk of spreading tumor cells and generally is not indicated.

C Surgical management

Benign lesions

Because most masses are found in the larger, superficial lobe, superficial parotidectomy is usually sufficient.

Complete excision is required. “Shelling out” a mass is unacceptable and often leads to a recurrence.

Malignant lesions

If the lesion is small, low grade, and completely confined to the superficial lobe, then resection of only that lobe may be sufficient. Otherwise, total parotidectomy should be performed.

The facial nerve should be sacrificed if it is involved. Nerve grafting allows restoration of some function in 6–12 months.

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Radical neck dissection or modified radical neck dissection is indicated for high-grade lesions.

Postoperative radiation therapy may be used for unfavorable high-grade lesions or in patients in

whom a limited dissection was performed.

Critical Points

The parotid is the largest of the salivary glands. It covers the masseter muscle and extends posteriorly behind the ramus of the mandible. Thus, masses palpated in the region just in front of the ear may actually be located in the parotid, and appropriate workup must be undertaken.

The gland is enclosed by a dense fascial sheath and consists of a larger superficial and a smaller deep “lobe” with branches of the facial nerve passing between the two. Drainage of the gland is via Stenson's duct.

The majority of neoplasms (80%) arising in the parotid are benign. The most common presentation is that of a painless mass without evidence of nerve involvement.

Pleomorphic adenomas or “mixed tumors” are the most common benign neoplasm, making up about 60% of parotid tumors overall.

Papillary adenocystoma (cystadenoma) lymphomatosum or Warthin's tumor are typically soft, contain mucoid material, and are more common in women between 40 and 60 years of age.

Benign lymphoepithelial tumor, or Godwin's tumor, may mimic a lymphoma or inflammatory process.

Only 20% of neoplasms are malignant tumors and are more frequently associated with pain or facial paralysis.

Mucoepidermoid tumors, which may be either low grade or high grade, are the most common malignant neoplasms.

Malignant mixed tumors are the second most common malignancy.

Squamous cell carcinomas are rare. An effort must be made to rule out the parotid lesion as a mestastasis from some other site in the head and neck.

Trauma to Stensen's duct should be primarily repaired over a stent.

Acute suppurative parotitis is usually seen in debilitated patients and is typically caused by S. aureus. Initial treatment is hydration, antibiotics, and stimulation of salivation. Surgical therapy is wide drainage.

Calculus sialadenitis is caused by stones in the salivary ducts. Treatment involves either extraction through Stensen's duct or surgical removal via an external excision.

Evaluation of a parotid mass involves a detailed head and neck examination. The constellation of symptoms and physical examination findings typically differentiate among the pathologic possibilities (see VI A ). Axial imaging (either MRI or CT) may give additional useful information. Fine -needle aspirations may be helpful in clarifying the clinical situation but are not always necessary. Core biopsy or open biopsy should not be performed.

Surgery for benign lesions is usually limited to superficial lobectomy. “Shelling out” a lesion is never acceptable.

Surgery for malignant lesions may include only a superfical lobectomy if the lesion is small, low grade, and confined to the superficial lobe. Otherwise, total parotidectomy should be performed. The facial nerve is sacrificed, if involved. Neck dissection is included for highgrade lesions. Radiotherapy may be given for high-grade lesions or where an incomplete dissection is performed.

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Study Questions for Part VI

Directions: Each of the numbered items in this section is followed by several possible answers. Select the ONE lettered answer that is BEST in each case.

1. A 35 -year-old man presents with left unilateral tinnitus and mild left sensorineural hearing loss. Which of

the following statements is true?

A Such signs and symptoms are common and should not be worked up unless they worsen.

B An MRI scan should be obtained, but gadolinium enhancement and its attendant risks are not necessary. C Brain stem evoked response audiometry is likely to be normal.

D The patient should be assumed to have an acoustic neuroma until proven otherwise. E Conditions that cause such problems do not affect the other ear.

View Answer

Questions 2–3

A 35 -year -old man has right -sided serous otitis media and a right upper neck mass.

2.It is most important to evaluate this patient for which of the following?

A Cancer of the right ear B Cancer of the right tonsil

C Cancer of the right maxillary sinus D Cancer of the nasopharynx

E Hodgkin's lymphoma View Answer

3.Which of the following will be the primary treatment for this tumor?

A Local excision to negative margins

B Wide local excision and radical neck dissection

C Neoadjuvant chemotherapy followed by resection of residual tumor

D Unilateral radiotherapy with combined chemotherapy

E Bilateral radiotherapy

View Answer

Questions 4–5

A 65 -year -old man is found to have a small invasive squamous cell carcinoma of the right vocal cord. The right vocal cord is paralyzed, and a lymph node in the right anterior neck is 4 cm in diameter.

4.The stage of the tumor is which of the following?

A T2N1 B T2N2a C T3N1 D T3N2a E T4N3

View Answer

5.Optimal treatment of the primary tumor should include which of the following?

A Total laryngectomy

B Vertical hemilaryngectomy

C Supraglottic (horizontal) laryngectomy D Right cordectomy

E Chemotherapy View Answer

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Questions 6–7

A 55 -year -old woman presents with complaint of a mass overlying the angle of the right mandible. She says the mass has been slowly enlarging over the past 2–3 years and that the mass is painless. On physical examination, it is firm and overlies the angle of the right mandible and the area between the angle and the tragus of the ear. Neurologic examination of the head and neck is completely normal.

6. Which of the following does this mass most likely represent?

A Mucoepidermoid cancer of the parotid gland B Acute parotitis

C Benign mixed tumor of the parotid gland (pleomorphic adenoma)

D Malignant mixed tumor of the parotid gland

E Hemangioma of the parotid gland

View Answer

7. What will be the optimal treatment for this lesion?

A Radiation therapy

B Total parotidectomy with preservation of the facial nerve C Total parotidectomy including resection of the facial nerve D Superficial parotidectomy

E Enucleation

View Answer

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Answers and Explanations

1. The answer is D (Chapter 18, IV F 2). These are common presenting systems of an acoustic neuroma. Evaluation for acoustic neuroma is indicated in all cases of unilateral hearing complaints, especially when hearing loss is documented. Magnetic resonance imaging (MRI) of the brain with internal auditory canal views and gadolinium contrast is sensitive in 98% of patients with acoustic neuroma. Complications associated with gadolinium are exceedingly rare, and this contrast should always be used in an MRI to look for a tumor. Brain stem auditory response testing may or may not be normal in cases such as this. The differential diagnosis with this presenting complaint is quite extensive, and it includes processes that result in bilateral hearing loss.

2–3. The answers are 2-D and 3-E (Chapter 19, IV C; Chapter 19, IV B 2, C 2 b). The two most common presenting symptoms of cancer of the nasopharynx are enlarged posterior cervical lymph nodes and unilateral serous otitis media. Cancer of the right ear, right tonsil, or right maxillary sinus or Hodgkin's lymphoma generally do not cause otitis media and usually occur in an older age group. Hodgkin's lymphoma will lead to serous otitis media only if Waldeyer's ring involvement has led to eustachian tube dysfunction, which is a rare occurrence.

Bilateral radiotherapy is the primary treatment for all epithelial nasopharyngeal tumors.

4–5. The answers are 4-D and 5-A (Chapter 19, II C 3, VIII D 3; Chapter 19, VIII E 4). Any carcinoma of the vocal cord that leads to fixation of the cord or of the hemilarynx is at least T3. Massive involvement of surrounding soft tissues will make the tumor stage T4. The presence of a single homolateral lymph node greater than 3 cm but less than 6 cm in diameter makes the stage of the neck node N2a. Multiple small lymph nodes on the same side of the neck as the primary tumor are classified N2b, and lymph nodes involving the opposite side of the neck change the staging to N3.

T3 tumors cannot be adequately treated with partial laryngectomy in most cases; total laryngectomy is required. Radiation therapy is used postoperatively as a planned combined treatment in most cases. Chemotherapy is used for inoperable cases or in experimental protocols.

6–7. The answers are 6-C and 7-D (Chapter 20, II A 1–4 ). The history given is most consistent with a benign neoplasm of the parotid gland. Benign mixed tumors are the most common benign tumors of the salivary glands. Benign salivary tumors account for 60% of all parotid tumors. Malignant tumors, such as a mucoepidermoid cancer, usually grow more rapidly and are more often associated with facial nerve paralysis. The absence of pain makes acute parotitis unlikely. Hemangiomas of the parotid gland are much rarer than benign mixed tumors.

The optimal treatment for a benign mixed tumor is removal of the tumor with a margin of normal parotid gland. This usually can be accomplished with a superficial parotidectomy. Although these tumors often appear to shell out, removal by simple enucleation results in a very high recurrence rate. Excision of the entire gland with or without the facial nerve is indicated for malignant tumors. Radiation therapy does not have a role in the management of this lesion.

Chapter 21

Trauma and Burns

Murray J. Cohen

Michael Weinstein

Kris R. Kaulback

Jerome J. Vernick

Nasim Ahmed

I Trauma

AOverview

Incidence

Trauma is the leading cause of death for people 1–44 years of age.

More than 150,000 people die from trauma every year.

Half of these deaths result from motor vehicle accidents.

For every death, three people are permanently disabled.

Trauma -related costs exceed 400 billion dollars annually.

Trauma management

Mortality can be greatly reduced by efficient handling of the injured, which involves three major components:

A trauma center with professional personnel who are trained in delivering rapid care and with facilities capable of handling a large number of patients at once

A transportation system capable of rapid transport to a trauma center

Emergency medical technicians who are capable of maintaining vital functions until the trauma surgeon can take over

Priorities. The management of trauma requires adherence to an established order of priority, ensuring that the most life -threatening injuries will be treated first but that less serious injuries will not be neglected after resuscitation. The order of priorities in evaluating trauma patients is based on the advanced trauma life support (ATLS) course administered by the American College of Surgeons (ACS).

Primary survey.

A—Airway

B—Breathing (ventilation)

C—Circulation

D—Disablility (neurologic deficit)

E—Exposure/Enviroment

The physician or emergency medical technician is urged to:

A—Establish a patent airway

B—Ensure that both lungs are ventilated

C—Restore circulating volume and compress external bleeding sites

D—Check for neurologic deficit

E—Fully expose (undress) the patient and cover with warmed blankets

Diagnosis of immediately life -threatening injuries, followed by rapid treatment

Reassessment of the patients' status

Secondary survey, “AMPLE” history (Table 21 -1), head-to -toe physical exam, Glasgow Coma Scale (GCS) (Table 21 -2)

Definitive treatment, including surgery, prophylactic antibiotics, and tetanus prophylaxis (see Chapter 2, VI)

B Mechanisms of injury

Knowing the mechanism of injury allows the physician to anticipate lesions that may otherwise remain undiagnosed and to decide on the appropriate management for lesions that may be more extensive than they might initially appear.

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TABLE 21-1 Points Covered in the “AMPLE” History

Allergies

Medications

Previous illnesses

Last meal

Events surrounding injury

Acceleration–deceleration injuries are typically caused by falls from heights, blunt trauma, or vehicular accidents.

Obvious injuries result from direct contact with the landing site (i.e., the ground or the vehicle).

Subtle injuries result from shearing forces produced by the momentum when heavy organs are suddenly halted or accelerated by a crash.