Difficult problems in thyroid cancer surgery.

The incidence of thyroid cancer has increased dramatically, yet the mortality has remained unchanged. There remain many challenges and "difficult problems" in diagnosing and treating patients with differentiated thyroid cancer (DTC). A significant percentage of patients with DTC will present with a thyroid nodule and an indeterminate fine needle aspiration biopsy underscoring the importance of proper evaluation and management. It is important when considering the extent of thyroidectomy and the management of lymph node metastases to balance the outcome of treatment in terms of recurrence and mortality with the morbidity of the procedure. Total thyroidectomy and lymphadenectomy for macroscopic lymph node metastases appear to be the optimal therapy for most patients with DTC. Preservation of function is a priority in managing patients with DTC invading the recurrent laryngeal nerve, trachea, esophagus, or the larynx.

The biomechanical consequences of longirostry in crocodilians and odontocetes.

Unrelated clades of aquatic tetrapod have evolved a similar range of skull shapes, varying from longirostrine (elongate and narrow rostrum) to brevirostrine (short rostrum). However, it is unclear which aspects of organismal performance are associated with this convergence in the range of skull shapes. Furthermore, it is not known how fundamental anatomical differences between groups influence these relationships. Here we address this by examining the load bearing capabilities of the skulls of two of the most diverse groups of living aquatic tetrapod: crocodilians and odontocetes. We use finite element analysis to examine the abilities of different cranial morphologies to resist a range of biologically relevant feeding loads including biting, shaking and twisting. The results allow for form/function relationships to be compared and contrasted between the two groups. We find that cranial shape has similar influences on performance during biting, shaking or twisting load cases at the anterior tooth positions, e.g. brevirostrine species experienced less strain than longirostrine species. The pattern of this form/function relationship is similar for both crocodilians and odontocetes, despite their fundamentally different anatomies. However, when loading teeth at the posterior end or middle of the tooth row the results do not follow the same pattern. Behavioural differences in bite location plays a key role in determining functional abilities in aquatic tetrapod taxa.

Constructing an Invasion Machine: The Rapid Evolution of a Dispersal-Enhancing Phenotype During the Cane Toad Invasion of Australia.

Biological invasions can induce rapid evolutionary change. As cane toads (Rhinella marina) have spread across tropical Australia over an 80-year period, their rate of invasion has increased from around 15 to 60 km per annum. Toads at the invasion front disperse much faster and further than conspecifics from range-core areas, and their offspring inherit that rapid dispersal rate. We investigated morphological changes that have accompanied this dramatic acceleration, by conducting three-dimensional morphometric analyses of toads from both range-core and invasion-front populations. Morphology of heads, limbs, pectoral girdles and pelvic girdles differed significantly between toads from the two areas, ranging from 0.5% to 16.5% difference in mean bone dimensions between populations, with invasion-front toads exhibiting wider forelimbs, narrower hindlimbs and more compact skulls. Those changes plausibly reflect an increased reliance on bounding (multiple short hops in quick succession) rather than separate large leaps. Within an 80-year period, invasive cane toads have converted the basic anuran body plan - which evolved for occasional large leaps to evade predators - into a morphotype better-suited to sustained long-distance travel.

Gallbladder volvulus in the elderly. An emergent surgical disease.

Volvulus of the gallbladder is an extremely rare condition presenting often in elderly patients commonly mimicking acute cholecystitis. Two cases of gallbladder volvulus in two octogenarian patients are presented from our institution. Clinical presentation is reviewed and some characteristic clinical and radiographic findings are described. The etiology of this rare entity is discussed with particular emphasis on visceroptosis, a common finding in elderly patients. The importance of early recognition and rapid treatment of this potentially fatal disease is emphasized. It is possible with increasing longevity, with its accompanying tendency to visceroptosis, that this entity may occur more frequently in the future. Its recognition and proper treatment is essential to good results in this elderly group of patients.

Hypothyroidisim following hemithyroidectomy: incidence, risk factors, and management.

BACKGROUND: The purpose of this study was to characterize the hypothyroidism that occurs following hemithyroidectomy. METHODS: The records of all euthyroid patients who underwent hemithyroidectomy from 1992 to 2000 were reviewed to determine the frequency of postsurgical hypothyroidism and the predisposing factors. All patients were evaluated for age, gender, serum thyrotropin (TSH) levels, weight of resected thyroid tissue, and associated thyroiditis. Hypothyroid patients were evaluated for symptoms, timing of diagnosis, and treatment doses of levothyroxine (L-T(4)). RESULTS: Hypothyroidism was diagnosed in 25 (35%) of 71 patients, subclinical in 16 and overt in 9 with a mean postoperative TSH level of 8.51 +/- 6.53 microIU/L. The mean preoperative TSH level was 1.94 +/- 1.00 microIU/L in hypothyroid compared with 1.10 +/- 0.74 microIU/L in euthyroid patients (P <.05). Lymphocytic thyroiditis was present in 10 (40%) of 25 hypothyroid compared with 10 (22%) of 46 euthyroid patients (P = not significant). There were no significant differences in age, gender, or weight of resected thyroid tissue. The average therapeutic dose of L-T(4) was 1.3 microg/kg (range, 0.5 to 1.9 microg/kg). All but 2 hypothyroid patients were diagnosed within 2 months of operation. CONCLUSIONS: Hypothyroidism following hemithyroidectomy occurs in patients with higher preoperative TSH levels, is usually mild and asymptomatic, and can be treated with reduced doses of L-T(4).

Recommendations for management of cystic thyroid disease.

BACKGROUND: Thyroidectomy has been advocated for cystic nodules that recur after 2 fine-needle aspiration biopsies (FNABs) because of concern for malignancy. METHODS: A review of patients with nodular thyroid disease was completed to determine the frequency of cystic nodules, significance of the color and volume of aspirated fluid, frequency and factors predictive of cyst resolution, and incidence of carcinoma in cystic nodules. RESULTS: Thyroid nodules were cystic in 70 (18%) of 389 patients. FNAB was diagnostic in 50 (71%) patients with no false-negative results. Cyst resolution occurred in 10 (14%) patients. The mean volume of fluid aspirated from cysts that resolved was 14 +/- 12 mL compared with 8 +/- 18 mL from recurrent cysts (P > .05). Thyroidectomy was performed in 28 (40%) patients because of an abnormal or persistently nondiagnostic FNAB or compressive symptoms. Six patients (8.6%) had cancer, with a mean nodule size of 3.8 +/- 2.3 cm compared with 3.7 +/- 2.6 cm in patients with benign cysts (P > .05). Hemorrhagic fluid was aspirated in 4 patients with and 36 without cancer (P > .05). CONCLUSIONS: FNAB of cystic thyroid nodules is rarely therapeutic and is a common cause of nondiagnostic rather than false-negative results. Recommendations for thyroidectomy should be based on FNAB rather than on size, fluid color, or failure of cyst resolution alone.

Outcome of serious blunt cardiac injury.

BACKGROUND: Although serious blunt cardiac injury (BCI) is usually fatal, patients who reach the hospital alive can have a spectrum of abnormalities. We attempted to define the clinical features that helped identify serious BCI and to evaluate outcome. METHODS: Patients with serious BCI at a level I trauma center were identified during a 3-year period. RESULTS: Twelve patients had serious BCI. Six patients had cardiac arrest, and six had unexplained hypotension. Specific injuries included acute myocardial rupture (two patients); valvular disruption (two); myocardial contusion associated with either cardiac failure (two), complex ventricular arrhythmias (two), or delayed myocardial rupture (one), or present at autopsy (two); and coronary artery thrombosis (one). Seven of eight patients who did not have associated fatal injuries survived. Electrocardiography suggested cardiac injury in all nine patients in whom it was done, and echocardiography was useful to establish the diagnosis in four of five patients. Creatine phosphokinase isoenzyme levels did not distinguish serious injuries. CONCLUSIONS: The outcome of serious blunt cardiac injury can be favorable if patients have signs of life on arrival at the hospital, the signs of injury are recognized promptly, and other injuries do not supervene.

Risk factors for postthyroidectomy hypocalcemia.

BACKGROUND: Hypocalcemia is a common sequela of thyroidectomy; however, its causative factors have not been completely delineated. METHODS: A prospective study of 60 patients who underwent unilateral (n = 15) or bilateral (n = 45) thyroidectomy between 1990 and 1993 was completed to determine the incidence and risk factors for hypocalcemia. Free thyroxine, thyrotropin, and alkaline phosphatase levels were obtained before operation in all patients, together with preoperative and postoperative ionized calcium, parathyroid hormone (PTH), calcitonin, and 1,25-dihydroxyvitamin D3 levels. All patients were examined for age, gender, extent of thyroidectomy, initial versus reoperative neck surgery, weight and pathologic characteristics of resected thyroid tissue, substernal thyroid extension, and parathyroid resection and autotransplantation. RESULTS: Hypocalcemia, defined by an ionized calcium level less than 4.5 mg/dl, occurred in 28 patients (47%), including nine (15%) symptomatic patients who required vitamin D and/or calcium for 2 to 6 weeks. In no patient did permanent hypoparathyroidism develop. With a multivariate logistic regression analysis, factors that were predictive of postoperative hypocalcemia included an elevated free thyroxine level (p = 0.003), cancer (p = 0.010), and substernal extension (p = 0.046). CONCLUSIONS: Postoperative decline in parathyroid hormone was not an independent risk factor for hypocalcemia, indicating that other factors besides parathyroid injury, ischemia, or removal are involved in the pathogenesis of postthyroidectomy hypocalcemia. An elevated free thyroxine level, substernal thyroid disease, and carcinoma are risk factors for postthyroidectomy hypocalcemia, and their presence should warrant routine postoperative calcium measurement. In the absence of these risk factors, routine postoperative measurement of serum calcium is unnecessary.

Amiodarone-induced thyrotoxicosis: clinical presentation and expanded indications for thyroidectomy.

BACKGROUND: Amiodarone-induced thyrotoxicosis (AIT) is a rare disorder that is frequently refractory to conventional pharmacologic therapy. METHODS: An analysis of seven patients who underwent thyroidectomy for control of AIT between 1987 and 1993 was completed to examine the clinical manifestations and the indications for surgical therapy. RESULTS: Five men and two women, 53 to 72 years of age, had AIT after 3 to 55 months of amiodarone treatment (mean, 21 months). The primary manifestations of AIT were ventricular tachycardia (five), exacerbation of chronic pulmonary disease (one), and occult hyperthyroidism (one). Medical therapy included propylthiouracil in doses up to 1200 mg/day in five patients, a beta-receptor antagonist in three, and withdrawal of amiodarone in five. Near-total or total thyroidectomy resulted in resolution of thyrotoxicosis in all patients. Morbidity included pneumonia (one) and cardiac dysrhythmias (two). One patient died of ventricular dysrhythmias 4 months after thyroidectomy. The mean thyroid weight was 50 gm (range, 17 to 216 gm). Microscopic examination showed destructive follicular lesions with fibrosis in all patients. Associated thyroid pathologic condition included multinodular goiter in four patients and a follicular adenoma in one. CONCLUSIONS: AIT may be clinically occult or manifested by unusual symptoms requiring a high index of suspicion for diagnosis. Near-total thyroidectomy is safe and effective in producing rapid resolution of AIT and is indicated for the initial treatment of patients who present with a resurgence of life-threatening cardiac arrhythmias and for all patients with AIT refractory to medical therapy.

Follicular or Hürthle cell neoplasm of the thyroid: can clinical factors be used to predict carcinoma and determine extent of thyroidectomy?

BACKGROUND: Fine-needle aspiration biopsy (FNAB) and frozen section exam are of limited or no value in distinguishing benign and malignant follicular or Hürthle cell neoplasms of the thyroid gland. METHODS: Patients who underwent thyroidectomy for treatment of a follicular or Hürthle cell neoplasm between 1990 and 1998 were identified and evaluated for age, gender, head and neck irradiation, nodule size, and cytologic atypia to determine whether clinical factors were predictive of carcinoma. RESULTS: Of the 352 patients evaluated for nodular thyroid disease, 75 (21%) underwent thyroidectomy after an indeterminate FNAB finding, 66 with follicular and 9 with a Hürthle cell neoplasm. Seventeen (23%) of the patients had carcinoma-follicular variant of papillary (10), follicular (6), and Hürthle cell (1). Carcinoma was diagnosed in 15 of 64 women and 2 of 11 men (P > .05). The mean age was 43 +/- 21 years and 50 +/- 16 years, respectively, in patients with and without carcinoma (P > . 05). Three patients had previous neck irradiation and none had carcinoma. Mean nodule size was 4.2 +/- 2.7 cm and 4.3 +/- 3.5 cm, respectively, in patients with and without carcinoma (P > . 05). Cytologic atypia was present in 8 of 17 patients with carcinoma and 20 of 58 patients without carcinoma (P > .05). CONCLUSIONS: Clinical factors were not helpful in predicting carcinoma in patients with an indeterminate FNAB finding and thus cannot be used to reliably select patients for more extensive thyroidectomy.

Intraoperative parathormone level measurement in the management of hyperparathyroidism.

To investigate the potential use of intraoperative intact parathormone measurements to predict curative parathyroidectomy, we measured ionized calcium (Cai) levels and parathormone levels in 33 patients with hyperparathyroidism who underwent exploratory bilateral neck surgery. Nineteen patients each had a solitary adenoma, 13 patients had hyperplasia, and one patient had four normal parathyroid glands. These results were compared to the results for 37 patients who underwent either thyroid lobectomy (TL) (n = 10) or near-total thyroidectomy (NTT) (n = 27) and of 14 control patients who underwent miscellaneous operations. Parathormone decline after curative parathyroidectomy was 86.4 +/- 1.2% (mean +/- SE), which was significantly greater than a decline of 25.7% +/- 9.8% in three patients with persistent postoperative hyperparathyroidism (p less than 0.01). Declines were 38.5% +/- 8.7% after TL (p less than 0.01), 52.2% +/- 5.9% after NTT (p less than 0.01), and 8.3% +/- 4.3% (p less than 0.01), in the control patients. An intraoperative Cai decline of 4.0% +/- 0.6% after curative parathyroidectomy did not differ significantly from the results after TL, NTT, or miscellaneous operations in the control patients. Patients with persistent postoperative hyperparathyroidism had the greatest decline in Cai levels (7.1% +/- 2.3%; p less than 0.05). From these data we conclude that (1) a decline in parathormone level of 70% or more 20 minutes after parathyroidectomy is predictive of cure, (2) thyroidectomy, even unilaterally, produces a significant decline in parathormone level that affects interpretation of intraoperative parathormone level changes, (3) Cai level because of its slow decline is not useful in predicting effective parathyroidectomy, and (4) measurement of intraoperative parathormone level changes should not be used as a substitute for exploratory bilateral neck surgery.

Oral calcium load test: diagnostic and physiologic implications in hyperparathyroidism.

An oral calcium load test (CLT) (1 gm Ca/50 kg) was administered to 11 control subjects and 35 patients with overt hyperparathyroidism to assess its efficacy in diagnosis of hyperparathyroidism. All participants were placed on a low-calcium diet 3 days before the CLT. Intact parathormone and ionized calcium (Cai) levels were measured 0, 1, 2, and 3 hours after CLT. Initial Cai and parathormone (mean +/- SE) were 1.22 +/- 0.01 mmol/L and 2.94 +/- 0.03 pmol/L in the control group compared with 1.43 +/- 0.02 mmol/L and 10.6 +/- 2.2 pmol/L in the group with hyperparathyroidism. Both groups had a similar percent increase in Cai values (control, 5.9% +/- 0.8%; hyperparathyroidism, 6.3% +/- 0.6% (p greater than 0.1). A decline in parathormone levels of 47.6% +/- 2.8% in patients with hyperparathyroidism was significantly less than the 75.3% +/- 5.3% decline observed in control subjects (p less than 0.025). Three hours after CLT, parathormone was suppressed in control subjects, whereas a rebound occurred in patients with hyperparathyroidism. Postoperative CLT demonstrated a higher mean percent Cai increase and percent parathormone decline (Cai, 8.9% +/- 1.1%; parathormone, 67.9% +/- 1.8%) compared with preoperative values (Cai, 6.0% +/- 1.0%; PTH, 49.6% +/- 4.3%) (p less than 0.025), and 3 hours after calcium intake, parathormone remained suppressed, similar to control subjects. After surgery, three patients had elevated parathormone and low normal Cai levels and parathormone response to a CLT confirmed the diagnosis of secondary hyperparathyroidism. In conclusion, a CLT (1) can confirm the diagnosis of hyperparathyroidism and successful parathyroidectomy, (2) distinguished postoperative secondary from persistent primary hyperparathyroidism, (3) demonstrated nonautonomy of abnormal parathyroid glands with a parathormone response to a calcium load characterized by an earlier nadir, decreased suppressibility, and more rapid recovery, and (4) produced dynamic changes that did not distinguish patients with hyperparathyroidism from control subjects or hyperplasia from adenoma.

Polypropylene mesh closure after emergency laparotomy: morbidity and outcome.

BACKGROUND: Alternative methods for abdominal wall closure may be necessary after emergency laparotomy. The purpose of this study was to determine the morbidity and outcome of emergency fascial closure with polypropylene mesh. METHODS: A retrospective review was performed of all patients undergoing emergency fascial closure with polypropylene mesh from January 1990 to March 1994. RESULTS: Seventy patients were identified. Indications for mesh placement included visceral edema (40), infected/necrotic fascia (21), and planned reexploration (7). Enteric fistulas developed in five patients (7.1%). When omentum was interposed between intestine and mesh, the incidence of fistula was significantly reduced (0 of 51 vs 5 of 19, p < 0.01). Forty-two patients (60%) survived with wound closure, accomplished by skin flaps in 19 (45%), skin grafting in 11 (26%), and secondary healing in 6 (14%). The mesh was removed in six patients (14%). Complications of mesh extrusion and hernia occurred less often after skin flap closure compared with skin grafting or secondary healing (1 of 19 vs 9 of 17, p < 0.01). No mesh infection occurred. CONCLUSIONS: Polypropylene mesh placement is an effective alternative for abdominal closure after emergency laparotomy, even when intraabdominal sepsis is present. Fistulas associated with its use may be effectively eliminated by the interposition of omentum between bowel and mesh. Wound closure with full-thickness skin flaps is the preferred method for soft tissue coverage when mesh is used.

Familial nonmultiple endocrine neoplasia medullary thyroid carcinoma: an evolving clinical entity.

BACKGROUND: A rare kindred of familial nonmultiple endocrine neoplasia medullary thyroid carcinoma arising from a 73-year-old proband case is reported to further define this distinct entity. METHODS: Twenty-four family members across four generations, four with medullary thyroid carcinoma (MTC) and two with C-cell hyperplasia (CCH), were studied. RESULTS: Basal calcitonin levels were elevated in three patients with MTC and were normal in one patient with microscopic MTC and two patients with CCH who had persistent subtle elevation in calcium and/or pentagastrin-stimulated calcitonin levels. One patient had unilateral MTC without CCH. Associated abnormalities included papillary carcinoma (2), thyroiditis (4), adenoma (2), and colloid nodule (1). Minimum treatment was total thyroidectomy. Two patients with MTC and marked hypercalcitonemia have recurrent disease at 2.5-year and 11-year follow-up. Two patients with MTC and normal or minor elevations in basal calcitonin and two with CCH had normal provocative calcitonin testing at 6 to 18 months follow-up. CONCLUSIONS: Unilateral MTC without CCH and MTC in the elderly do not preclude a familial cause. Microscopic MTC or CCH may be seen with subtle elevations in stimulated calcitonin levels, and recognition allows for curative thyroidectomy. Other apparent dominant thyroid pathologic conditions may occur concomitantly with familial medullary thyroid carcinoma and thus routine calcitonin, and immunohistochemical testing should be performed in patients with an appropriate family history.

Lithiumogenic disorders of the thyroid and parathyroid glands as surgical disease.

Little notice has been paid in the surgical literature to problems with psychoeffective lithium, which by interfering with adenylate cyclase affects thyroid and parathyroid function, causing hypercalcemia, hyperparathyroidism, and hypothyroidism. Seven patients with lithiumogenic hyperparathyroidism occurring after years of lithium therapy underwent treatment and manifested osteoporosis (n = 2), hypertension (n = 2), nephrolithiasis (n = 1), coma (n = 1), rising hypercalcemia (n = 1), goitrous myxedema (n = 4), nephrogenic diabetes insipidus (n = 2), renal failure (n = 2), and hyperlipidemia (n = 1). Disease-directed parathyroidectomy (without morbidity) was curative. Unique laboratory findings included normal serum phosphorus and reduced urinary calcium and cyclic adenosine monophosphate values. Three separate cases of thyroid carcinoma after long-term lithium therapy were also treated, being preceded by myxedema (n = 2) and concurrent with hyperparathyroidism (n = 1). There has been only one previous report of lithium-associated thyroid carcinoma. All patients taking lithium should undergo surveillance for thyroid and parathyroid dysfunction and neoplasia, and appropriate surgical and medical treatment should be considered in each situation. Although hyperparathyroidism may be reversible with lithium discontinuance, such therapy may be obligatory for patient well-being, thus dictating parathyroidectomy.

Lithium effects on dispersed bovine parathyroid cells grown in tissue culture.

It is not clear whether hypercalcemia and hyperparathyroidism associated with lithium therapy are the result of an unmasking of preexisting disease or a direct effect of lithium on the parathyroid glands. To investigate this phenomenon, parathyroid hormone (PTH) secretion and cytosolic calcium concentrations [( Ca]i) were measured in normal and lithium-treated dispersed bovine parathyroid cells grown in tissue culture and incubated with varying concentrations of extracellular calcium [( Ca]e) (0.5 to 2.5 mmol/L). Results indicate that lithium has two effects on parathyroid secretory response: (1) a decrease in low calcium-stimulated PTH release and (2) a potentiation of PTH release at physiologic concentrations of extracellular calcium. [Ca]i was assessed by use of fura-2, a calcium-sensitive fluorescent indicator. Resting [Ca]i levels were unaffected by lithium (103 +/- 13 nmol/L in controls vs 101 +/- 5 nmol/l in lithium-treated cells, mean +/- SE). Subsequent increases in [Ca]i in response to increases in [Ca]e were significantly less in lithium-treated cells, with no difference at maximal [Ca]e. Increases in [Ca]i in response to a submaximal concentration of extracellular magnesium were also blunted in cells pretreated with lithium. In conclusion, our data suggest that, at physiologic calcium concentrations, lithium decreases parathyroid cell sensitivity to changes in [Ca]e, reducing [Ca]i levels and increasing PTH secretory response.

Refined use of scintigraphy in the evaluation of nodular thyroid disease.

BACKGROUND: Scintigraphy has been advocated in patients with a thyroid nodule when fine needle aspiration biopsy (FNAB) is not definitive. The purpose of this study was to determine the incidence of hyperfunctioning nodules in patients without a definitive FNAB, the correlation of serum thyrotropin (TSH) levels with the functional status of a nodule, and whether a sensitive TSH assay can be used in lieu of scintigraphy. METHODS: From 1990 to 1996, patients with a thyroid nodule were evaluated with FNAB and serum TSH measurement. Iodine-123 scintigraphy was reserved for patients without a definitive FNAB and was correlated with TSH levels. RESULTS: Of 356 patients with a thyroid nodule, 102 did not have a definitive FNAB. A hyperfunctioning nodule was diagnosed in 14 of the 102 patients. A low TSH level was detected in 12 (86%) of 14 patients with a hyperfunctioning nodule (mean = 0.04 +/- 0.38 microIU/mL) and only 20 (23%) of 88 patients with a hypofunctioning nodule (mean = 0.87 +/- 4.11 microIU/mL) (P < .05). Only 2 of 70 (2.8%) patients with a normal or increased TSH level had a hyperfunctioning nodule. CONCLUSIONS: A 14% incidence of hyperfunctioning nodules in patients without a definitive FNAB warrants the use of scintigraphy but only when serum TSH levels are low, thus avoiding unnecessary scans in 91% of patients with a thyroid nodule.

Monomicrobial necrotizing fasciitis complicating pregnancy and puerperium.

BACKGROUND: Necrotizing fasciitis is an uncommon, rapidly progressive, life-threatening infection involving the subcutaneous tissue and fascia. Usually, it is a synergistic polymicrobic infection that occurs in patients with coexisting factors predisposing them to bacterial inoculation and the spread of infection. CASES: We report a monomicrobial variant of necrotizing fasciitis affecting three otherwise healthy pregnant or postpartum women. The necrotizing fasciitis involved either the lower extremity or the abdominal wall. The causative bacteria were Streptococcus pyogenes (two cases) and Staphylococcus aureus (one). All patients presented with an acute fulminant infection, including one woman who died from overwhelming sepsis. CONCLUSION: These cases raise a question about the possible role of increased bacterial virulence and the immunologic changes of pregnancy as potential predisposing factors in the development of necrotizing fasciitis.

Parathyroid localization with technetium-99m-sestamibi: a prospective evaluation.

BACKGROUND: The purpose of this study was to prospectively evaluate parathyroid localization using technetium-99m-sestamibi (MIBI). STUDY DESIGN: Technetium-99m-sestamibi scintigraphy was performed in 124 patients with hyperparathyroidism and the results were correlated with serum calcium and parathyroid hormone (PTH) levels, weight, location, and pathology of parathyroid tissue, and associated thyroid abnormalities. RESULTS: Hyperparathyroidism was primary in 118 patients, secondary in four patients, and tertiary in two patients. The parathyroid pathology was a solitary adenoma in 95 patients (77 percent), double adenoma in five (4 percent), hyperplasia in 14 (11 percent), carcinoma in one (1 percent), and unconfirmed in nine (7 percent) who underwent noncurative parathyroidectomy. Associated thyroid disease was present in 29 (23 percent) patients. Fourteen patients (11 percent) had undergone previous parathyroid exploration. The mean calcium level was 11.4 +/- 0.8 mg/dL (range, 8.3 to 13.7 mg/dL) and the mean adjusted PTH level was 395 +/- 702 (range, 70 to 4,331). The sensitivity and positive predictive value of MIBI scintigraphy were 81 and 89 percent, respectively, in patients with a solitary adenoma and 37 and 100 percent, respectively, in patients with multiglandular disease. The mean adjusted PTH level was higher in patients with true-positive scans compared with false-negative scans (440 +/- 628 compared with 243 +/- 499, p > 0.05). The mean adenoma weight was 1,877 +/- 3,212 mg in patients with a true-positive scan compared with 485 +/- 296 mg with a false-negative scan (p > 0.05). CONCLUSIONS: The sensitivity and positive predictive value of MIBI scintigraphy is comparable to or better than the results reported for other localization procedures. Its lack of sensitivity for detection of multiglandular disease precludes its use in lieu of routine bilateral neck exploration in the management of patients with hyperparathyroidism.