Minimal-access parathyroid surgery using intraoperative parathyroid hormone assay.

OBJECTIVES: Review the most current preoperative localization imaging techniques in patients with primary hyperparathyroidism and demonstrate their applicability to targeted tumor removal with intraoperative parathyroid hormone (PTH) monitoring. STUDY DESIGN: Retrospective review of 40 consecutive patients undergoing parathyroid surgery with intraoperative PTH assay as the principal determinant of correction of the hyperparathyroid state. Details of the technology, cost analysis, and comparison with other management methods are discussed. METHODS: The standard intact PTH chemiluminescent assay (Nichols Diagnostics) and modifications to allow accelerated intraoperative results are discussed in detail. The time intervals between completion of parathyroid excision and postremoval assay and subsequent laboratory investigation present a practical therapeutic algorithm. RESULTS: Forty consecutive patients with hyperparathyroidism were treated surgically with intraoperative PTH as the determinant of satisfactory resolution of the disease state. In most instances, the surgical field was reduced to the targeted pathology identified by preoperative localization, and all patients became eucalcemic when this method was employed. Approximately half of eligible patients were treated under local anesthesia. CONCLUSIONS: Intraoperative PTH assay has added a new dimension to primary and revision parathyroid surgery. It is cost-effective and accurate and may reduce the morbidity of surgical intervention in revision procedures.

The ectopic parathyroid adenoma: a cost justification for routine preoperative localization with technetium Tc 99m sestamibi scan.

OBJECTIVES: To evaluate the cumulative costs of failure to identify the ectopic parathyroid adenoma when exploration without preoperative localization is performed and to compare these costs with the expenses of routine preoperative localization in every patient. DESIGN: A consecutive series of 59 patients with primary hyperparathyroidism studied with preoperative scans using technetium Tc 99m sestamibi and ultrasound was submitted to a cost analysis. A subset of 5 cases of ectopic adenomas, presumed to be unidentifiable on routine surgery, was similarly analyzed. SETTING: Academic tertiary referral center. METHODS: The operative, anesthesia, hospitalization, imaging, and physician reimbursement costs of a failed exploration are compared with the costs of preoperative technetium Tc 99m sestamibi and ultrasound scans in every patient. RESULTS: Two cases of mediastinal parathyroid adenomas in this consecutive series of 59 patients were given a theoretical cost, including hospitalization, physician reimbursement, and anesthesia fees. These costs were based on a failed cervical exploration and extracted from the record of an actual patient who underwent such a process at the University of Vermont, Burlington, in 1995. In addition, the records of 2 patients with intrathyroidal adenomas were submitted to the same theoretical cost analysis with the exception that these patients were assumed to have adenomas that could be discovered after prolonged cervical exploration and thyroid lobectomy. The net management and imaging costs for 4 cases of ectopic parathyroid adenomas undergoing theoretical failed exploration are compared with the cost of obtaining routine technetium Tc 99m sestamibi and ultrasound scans for each of the 59 patients. CONCLUSION: The added cost of protracted or failed cervical exploration nearly neutralized the costs of a routine preoperative localization with technetium Tc 99m sestamibi and ultrasound scans.

Lost airway during anesthesia induction: alternatives for management.

Pediatric and adult patients with upper airway obstruction pose several challenges to the anesthesiologist and otolaryngologist--head and neck surgeon. The initiation of general anesthesia and endotracheal intubation may progress to complete life-threatening respiratory decompensation with failure to achieve endotracheal intubation or mask ventilation. Hurried invasive maneuvers such as large-bore needle tracheal entry and cricothyrotomy are recognized salvage techniques, but other modes of extratracheal ventilation are now possible before surgical airway procedures are required. The laryngeal mask airway and esophagotracheal Combitube (Kendall Sheridan Health Care Products Co., Argyle, NY) are described, with examples of their clinical application. The combined technique of anterior commissure laryngoscopy and intubation with the gum elastic bougie is the preferred alternative for achieving tracheal entry when extratracheal ventilation cannot be accomplished. An algorithm for joint management of the problem airway by anesthesiologist and otolaryngologist--head and neck surgeon is illustrated.

Preoperative technetium Tc 99m sestamibi imaging. Paving the way to minimal-access parathyroid surgery.

OBJECTIVE: To examine the reliability of technetium Tc 99m sestamibi scanning as a new adjunct to the surgical management of hyperparathyroidism. DESIGN: Preoperative localization of parathyroid adenoma by technetium Tc 99m sestamibi delayed washing-out scanning and high-resolution ultrasound was compared with a historical institutional experience of surgical intervention without preliminary localization studies. A 10-year retrospective review from 1985 to 1995 of patients with surgical hyperparathyroidism was performed. SETTING: Academic tertiary referral medical center. PATIENTS: Thirty-three technetium Tc 99m sestamibi scans in patients with primary hyperparathyroidism were correlated with eventual surgical and pathologic findings. The last 10 patients were also studied with 10-MHz linear transducer ultrasound, and the results were compared with those of the radionuclide scan and eventual surgical and pathologic findings. From 1985 to 1995, 142 patients underwent surgical exploration for primary hyperparathyroidism, and 125 records were available for review. RESULTS: The technetium Tc 99m sestamibi parathyroid scan correctly identified the site and presence of 31 adenomas among 34 confirmed tumors, a sensitivity of 91% and positive predictive value of 97%. The scan detected three anterior mediastinal adenomas that could not be removed through cervical exploration. In each instance median sternotomy was included in the primary surgery and allowed efficient, successful management of these ectopic adenomas. High-resolution ultrasound correctly identified nine of 10 cervical parathyroid adenomas and predicted the volume of each tumor to a statistically significant level. CONCLUSIONS: Hyperthyroidism has traditionally been treated surgically without preliminary localization studies. We found both technetium Tc 99m sestamibi scanning and high-resolution ultrasound to be highly sensitive at detecting parathyroid adenomas at the 90% level. Furthermore, preoperative localization allowed efficient surgical intervention for our group of patients who had high frequency of mediastinal adenomas that required transmediastinal surgery.

Angiogenesis as a prognostic marker in early head and neck cancer.

Experimental evidence suggests that tumor growth beyond the earliest stages is dependent on angiogenesis, or neovascularization, and that angiogenesis may also promote metastasis. Recent clinical studies demonstrate that angiogenesis is a prognostic marker in breast, lung, and prostate cancer. To investigate whether tumor angiogenesis also correlates with metastasis and survival in early head and neck carcinoma, we quantified the microvascularity of 106 primary carcinomas prior to treatment and correlated the counts with eventual outcome after 3 to 15 years of follow-up. Microvessels were stained immunocytochemically for von Willebrand factor and then counted by light microscopy. Microvessels were counted per 200x and 400x fields, and their density was graded from 1 to 4, in the area of most intense neovascularization. We found that neither microvessel counts nor density grades correlated with metastatic disease, local recurrence, or survival in early head and neck carcinoma. These results are in contradistinction to those recently reported for other tumor sites.

Harris P. Mosher Award thesis. The recovery potential of the optic nerve.

Optic nerve dysfunction can be secondary to mass lesions, osseous compression states, inflammatory disorders, ischemia, increased cerebrospinal fluid pressure, and trauma. Representative clinical material from each of these areas is described, with an institutional review of 70 cases that were managed surgically. It is evident that compromise of optic nerve function can resolve with medical and surgical therapy. This clinical review is designed to highlight factors that favor this recovery. Although each condition has unique characteristics, an evaluation of clinical disorders that affect the nerve from globe to optic chiasm is presented as a comprehensive review of optic neuropathy. It is apparent from the literature that many questions need to be answered concerning the pathophysiology of optic nerve injury and the factors that influence recovery. A basic animal model for the analysis of these questions has been developed. An optic nerve injury produced in the cat leads to progressive loss of myelin but preservation of axons, the precise theoretic state that may be reversible with corticosteroid therapy or surgical management. Finally, the model may allow future study of the biochemical mediators of injury and the factors that promote recovery.

Fibrous dysplasia of the temporal bone: ten new cases demonstrating the spectrum of otologic sequelae.

monostotic. Although most patients had a conductive hearing loss, 17% of patients demonstrated profound sensorineural hearing loss ascribable to the lesion, and facial nerve sequelae were noted in nearly 10% of cases. Cholesteatoma complicated almost 40% of cases, usually in the form of a canal cholesteatoma. Ten new cases of temporal bone fibrous dysplasia are described not only to further clarify the spectrum of otologic sequelae but also to help illustrate available treatment options. In addition, this report documents, in three new cases, the previously undescribed progression of conductive hearing loss to profound sensorineural deafness secondary to fibrous dysplasia.

Bilateral arteriovenous malformation of the mandible.

Spontaneous bleeding from the molar gingiva may reflect the presence of a life-threatening vascular malformation. Sporadic reports of exsanguinating hemorrhage in the dental literature warn of the dangers of extraction, although deaths from unrecognized lesions or secondary to mandibular fracture still occur. Arteriovenous malformation (AVM) may be either unilateral or, less commonly, bilateral, and should be suspected in individuals with large lower facial hemangiomata. Two cases of near-exsanguinating hemorrhage from bilateral AVMs are discussed with the long-term management over a 3- to 20-year follow-up. The report underscores the failure of therapeutic embolization and the need for computed tomographic scanning as a corollary to angiography. A newer treatment with direct removal of the AVM and obliteration methods solves the hemorrhagic complications, reduces the potential for steal syndromes, and reduces the potential for recurrence.

The nasogastric tube syndrome.

The nasogastric tube can produce sudden, life-threatening bilateral vocal cord paralysis and is often an unrecognized cause of this clinical entity. The pathophysiologic mechanism is thought to be paresis of the posterior cricoarytenoid muscles secondary to ulceration and infection over the posterior lamina of the cricoid. Since our initial report of this entity in 1981, several cases have been photo-documented. Study of whole organ sections of an involved larynx have demonstrated the histopathology. Diabetic renal transplant patients appear to be particularly susceptible to the condition, due to prolonged gastroparesis and requirement for nasogastric tube drainage. Esophagoscopy should be performed promptly in these patients when pharyngodynia, hoarseness, or evolving stridor present in the postoperative period.

Mondini dysplasia: spontaneous cerebrospinal fluid otorrhea. New perspectives in management.

The Mondini dysplasia represents a developmental arrest during the embryogenesis of the inner ear. The malformation, commonly associated with deafness, is frequently heralded by meningitis secondary to communication of the middle ear with the subarachnoid space. Early recognition and successful repair of the CSF leak is important to avoid the sequelae of repeated episodes of meningitis. We believe the addition of CSF diversion in the form of a lumbar drain during and after surgery will result in improved success.

Cavernous hemangiomas of the internal auditory canal.

Cavernous hemangiomas are vascular malformations that are seldom found in the central nervous system. Four cavernous hemangiomas of the internal auditory canal and one of the cerebellopontine angle have been reported previously. We present a series of seven (six of which have never been reported) cavernous hemangiomas limited primarily to the internal auditory canal. Whereas all cases but one had marked unilateral sensorineural hearing loss, only two had preoperative facial nerve dysfunction. There are no specific symptoms or physical or audiometric findings to differentiate cavernous hemangiomas from acoustic neuromas. However, a hemangioma should be suspected when facial paralysis is present in conjunction with a small intracanalicular tumor as demonstrated by computed tomography or magnetic resonance imaging. The former reveals calcium stippling in the lesions, whereas magnetic resonance imaging reveals a high signal intensity on both T1- and T2-weighted images.

Optic nerve decompression.

Post-traumatic deterioration of vision requires thorough ophthalmologic evaluation, as well as computed tomographic scanning of the orbits and central visual pathways if no obvious ocular origins of the visual decrement are detected. When optic nerve trauma is a suspected etiology, the patient should be treated with megadose intravenous steroids, as well as optic nerve decompression performed after 12 to 24 hours if improvement of vision fails to occur.

The septal translocation procedure: an alternative to lateral rhinotomy.

Lesions deep in the nasal vault with contiguous sinus involvement often required a lateral rhinotomy for exposure. This procedure affords excellent surgical access, but requires a significant external incision. An alternative sublabial technique, with dislocation of the nasal septum into the opposite nasal passage, provides excellent surgical exposure for these same lesions, while external facial incisions are avoided. The text outlines the surgical technique and representative uses in optic nerve decompression, inverted papilloma, giant rhinolith, angiofibroma, and a variety of nasosinus and nasopharyngeal malignant lesions.