Parotid gland and parapharyngeal space imaging--the surgical significance.

Wise head and neck surgeons, for whom parotid gland surgery constitutes a substantial portion of their case load, make full use of the radiologist and cytologist in arriving at a rational pre-operative diagnosis. They utilize the skill of these allied consultants to qualify (by histology) and quantify (by staging) diffuse and mass lesions of the parotid gland (and subjacent parapharyngeal space) in order to evolve an effective surgical, radiation or other treatment plan. They understand the basic principles of diagnostic imaging and apply them to the clinical problem at hand. They minimize diagnostic and intra-operative "surprises", reduce intra-operative and post-operative complications and generally have a more "informed" patient and patient's family. The purpose of this manuscript is to discuss a contemporary role for diagnostic imaging in neoplastic (and other) diseases of the parotid gland and subjacent parapharyngeal space. Not all lesions of the parotid gland require imaging, although a pre-operative clinical photograph, including evidence of facial nerve function, is always welcome. Other lesions may need diagnostic imaging, from simple to complex and sophisticated, depending upon the problem. Properly used, effective and selective diagnostic imaging can improve the surgeon's confidence by providing a more realistic provisional diagnosis and a better pre-operative staging process and treatment plan, thereby avoiding the surgically unexpected and facilitating prognosis.

Parotid gland enlargement in HIV infection: clinical/imaging findings.

Parotid gland enlargement with or without facial paralysis may be the presenting clinical manifestation of AIDS. Submandibular involvement may occur as well. Failure to recognize this association may lead to inappropriate or unnecessary intervention in the investigation and treatment of the salivary gland enlargement. In this paper, we discuss the role of imaging techniques in the investigation of salivary gland enlargement, and identify the specific radiologic signs found in HIV infection. Demonstration of intraparotid or submandibular gland cysts with focal intraparotid mass lesion(s) on imaging may help to differentiate parotid gland enlargement due to HIV infection from the many other causes of parotid enlargement.

Mediastinal lymph node metastases from bronchogenic carcinoma: detection with MR imaging and CT.

Magnetic resonance (MR) imaging and computed tomography (CT) were compared in a prospective study of 48 patients for the detection of metastatic mediastinal lymphadenopathy from bronchogenic carcinoma. The images were interpreted by three experienced radiologists using a five-point rating scale, enabling receiver operating characteristic (ROC) analysis. Imaging results were evaluated against "truth" data based on analysis of surgical specimens from mediastinoscopy and thoracotomy. All MR images were cardiac gated to reduce cardiac motion artifacts in the mediastinum. MR and CT both performed well, as indicated by similar areas under the ROC curves of 0.779 +/- 0.039 for MR imaging and 0.781 +/- 0.038 for CT scanning. No strong correlation between nodal size and metastatic involvement could be found for either MR or CT results. As long as nodal size remains the sole criterion in the detection of metastatic mediastinal lymphadenopathy, MR imaging is unlikely to enable better interpretations than CT scanning.

A review of conventional and CT imaging in the evaluation of thyroid malignancies.

Conventional imaging modalities available for investigating suspected or confirmed malignancies of the thyroid are reviewed. CT scan, a relatively new tool in this area, is discussed in some detail, and its advantages outlined and illustrated with clinical examples.

Schwannoma of the intrasternomastoid portion of the spinal accessory nerve: sophisticated preoperative CT diagnosis and appropriate surgical management.

Neurogenic tumors of the cervical portion of the cranial nerves are rare, and hence frequently misdiagnosed and mismanaged. A unique case of an isolated schwannoma of the spinal accessory nerve was correctly diagnosed by the constellation of signs demonstrated on a CT examination. This led to appropriate surgical removal with full motor nerve preservation. The primary purpose of this manuscript is to demonstrate the qualitative and quantitative radiologic signs indicative of the diagnosis and the surgical management resulting therefrom. The second more subtle purpose is to demonstrate the sophisticated clinical implications which can result from effective high-technology imaging.

Thyroid cartilage imaging with diagnostic ultrasound. Correlative studies.

In 1976, Noyek observed that the thyroid cartilage framework of the larynx could be imaged by diagnostic ultrasound; the image appeared uniquely independent of the presence or absence of calcification. It was suggested that ultrasound, with its simple, nonroentgenographic, noninvasive features, might permit screening detection of thyroid cartilage destruction. It might, therefore, give direction to better computed tomographic (CT) imaging, and, specifically, more effectively identify T4 laryngeal cancer. Since that time, with improving generations of ultrasound transducers, more than 130 clinically correlated laryngeal ultrasound examinations have been recorded. Thirty CT, ultrasound, and pathologically correlated advanced cases of laryngeal carcinoma were critically evaluated by the Departments of Otolaryngology and Radiology at Mount Sinai Hospital, Toronto. Our diagnostic imaging approach has resulted in remarkably improved thyroid cartilage imaging by CT when "directed" by preliminary ultrasound.

Bilateral multilocular renal cysts.

Multilocular renal cystic disease is a rare, benign condition thought to occur unilaterally. We report a case of asynchronous, bilateral multilocular renal cystic disease, which suggests that unilaterality is not essential for diagnosis of this lesion.

Multiple myeloma involving the cricoid cartilage.

This presents a case report of a patient with multiple myeloma who developed such a lesion in the cricoid--a circumstance which has not previously been recorded.

Multi-imaging demonstration of distant metastases from ovarian carcinoma.

An unusual case of ovarian carcinoma is presented with extra-abdominal soft tissue metastasis. These demonstrate calcification on plain films and CT, as well as avid uptake of Tc-99m MDP.

Congenitally absent lumbar pedicle: a reappraisal.

Three patients who had a diagnosis of congenitally absent lumbar pedicle underwent CT examination. Findings showed that each patient had an aberrant hypoplastic pedicle plus a retroisthmic defect in the ipsilateral lamina rather than an absent pedicle. Axial CT was the diagnostic modality of choice; reformated images were of little value. The nature of the anomaly explains the difficulty in diagnosis by plain film radiography or tomographic study. The differential diagnosis to be considered from findings of plain film radiography includes pediculate thinning, neoplastic disease, neurofibroma, mesodermal dysplasia associated with neurofibromatosis, and vascular anomalies.

Giant leiomyoma of the esophagus.

A patient with a giant leiomyoma of the esophagus (1235 g) presented with persistent cough, intermittent fever, nocturnal pyrosis, and intermittent dysphagia for solid foods. Reconstruction after extirpation of the distal esophagus, the tumor, and the proximal stomach involved a Collis gastroplasty and a Nissen fundoplication using stapling technique. This combination of operations after resection was used to assure the best functional result possible in a young man with benign disease.

Thyroid tumor imaging.

Clinical assessment of a patient with a focal or diffuse thyroid tumor is but the first step in diagnostic evaluation. The diagnostic imaging process augments information obtained by the inspecting eye and the palpating hand; it allows the qualification (for example, cystic v solid) and the quantification (for example, size, extension, and assessment of physiologic function) of the thyroid tumor mass. This diagnostic input allows the establishment of a more realistic provisional diagnosis and directs a rational treatment approach to the patient. This presentation reviews the major imaging modalities available for thyroid tumor evaluation: diagnostic ultrasound, radionuclide scans, and conventional radiology and computed tomography. The applications of these various modalities and their critical potentials and limitations are placed in a contemporary clinical setting. It is hoped that an increasing familiarity with these imaging modalities will give better direction to the specialist in otolaryngology--head and neck surgery and greater surgical benefit to his or her patients.

Ludwig's angina following dental extraction as a cause of necrotizing mediastinitis.

A fatal case of Ludwig's angina is reported in which penicillin was used as the sole antibiotic. Bacteroides melanogenicus resistant by virtue of production of Beta-lactamase was present. It is suggested that a combination of penicillin and an antibiotic effective against anaerobes such as metronidazole is the most appropriate initial chemotherapy pending confirmation from the bacteriology laboratory.

CT of the larynx.

While conventional radiographic techniques are still of value in the radiologic work-up of the patient with laryngeal disease, computed tomography (CT) has assumed a dominant role, particularly in the pretreatment staging and post-treatment evaluation of the patient with cancer. Even prior to the present generation of high resolution, fast scan equipment, images were being generated that revealed information available in no other non-invasive way, offering two major advantages. Initially, CT's ability to depict cross-sectional (axial) anatomy allows the radiologist and surgeon to build a clear three dimensional image of the site and extent of disease. Secondly, CT discriminates small soft tissue density differences. Also, this latter capability allows a separation of lymph nodes and blood vessels if the study is done with intravenous contrast enhancement. These two outstanding imaging properties allow informed decisions to be made regarding the feasibility and/or extent of conservation or radical surgery in malignant disease and provide unique and critical information regarding cartilage and deep structures. Other advantages of varying importance include the speed of the examination, its noninvasive nature, and the comfort to the patient. This paper reviews normal CT anatomy and discusses, with illustrations, the major diagnostic applications of CT in laryngeal disease.

Percutaneous antegrade biliary drainage: a nonoperative approach to biliary obstruction.

Twenty-seven patients underwent percutaneous antegrade biliary drainage for obstructive jaundice. The serum bilirubin levels was elevated in all patients. Generalized pruritus was a major complaint. Twenty of the patients had had a laparotomy for malignant disease. Of the 24 patients in whom this method of drainage was successful, the obstructing lesion was found at the porta hepatis in 12 and in the extrahepatic bile ducts in 12. Metastatic disease was the commonest cause of obstruction. Following drainage the serum bilirubin level fell from a mean of 21.4 mg/dl (366 mumol/l) to a mean of 4.1 mg/dl (70.1 mumol/l) within a week. Pruritus was relieved. The major complications were transient cholangitis in five patients and inadvertent dislodgement of the catheter in four. In three of these patients another catheter was reinserted with ease. There was no peritonitis or uncontrolled bleeding. Twenty-one patients were able to leave hospital. Their mean survival time was 7.3 months. A multiperforated catheter manipulated through the obstruction has the advantage of permitting bile flow into the duodenum (antegrade) in contrast to external drainage (retrograde) by T- or U-tubes. Although the mean survival time with this method is similar to that with insertion of drainage tubes at the time of laparotomy, morbidity and mortality are reduced; this is important in view of the poor prognosis of bile duct obstruction due to malignant disease.