Israel Medical Association Journal

Background: Drug-induced thyrotoxicosis is not uncommon. It may worsen life-threatening arrhythmias and may be refractory to medical treatment. Near-total thyroidectomy presents a valid alternative to medical therapy and should be considered early in the management of the disease.

Objectives: To assess whether near-total thyroidectomy was a viable approach for our patients.

Methods: Twelve patients – 7 men and 5 women, aged 63 to 82 years – presented with drug-induced fulminant thyrotoxicosis following 1 to 12 months of amiodarone treatment (11 patients, mean 7 months) and after a 6 months course of interferon-alpha treatment (one patient). Medical therapy included propylthiouracil in doses up to 1200 mg/day in all patients and a beta-receptor antagonist in seven. Five patients had to stop amiodarone treatment and start high doses of steroids. A thyroid scan was performed in all patients using 5 mCi of Tc-99m pertechnetate. The thyroid scan showed absent uptake of the tracer in the thyroid bed in all patients, precluding the use of radioablation.

Results: Four patients (three with AIT[1] and one with interferon therapy) who did not respond to 3 months of medical therapy required surgical thyroidectomy due to severe unremitting thyrotoxicosis. A near-total thyroidectomy resulted in rapid correction of thyrotoxicosis, enabling continuation of the anti-arrhythmic drug. There were no intraoperative or postoperative arrhythmias. Subsequently, all patients recovered rapidly and remained well and euthyroid on thyroxine replacement therapy.

Conclusions: Since surgery results in rapid control of thyrotoxicosis and permits continued therapy with amiodarone, we suggest that near-total thyroidectomy warrants consideration as a definitive treatment for resistant amiodarone or interferon-induced thyrotoxicosis.

Background: Thyroidectomy for goiter is a common surgical procedure performed in most hospitals in Israel. Both general and ear, nose and throat surgeons are familiar with thyroidectomy for cervical goiters. In about 1–15% of thyroidectomies, the goiter is intrathoracic and requires somewhat different management. This topic has not been reviewed in the literature recently.

Objective: To evaluate the clinical presentation, preoperative workup, surgical complications and risk of malignancy in retrosternal goiters.

Methods: We retrospectively reviewed the records of 75 patients who underwent thyroidectomy for retrosternal goiter in the General Thoracic Surgical Department of our institution during a 15 year period, January 1990 to January 2005.

Results: All the patients (41 women and 34 men) were symptomatic at presentation, with choking and dyspnea being the most common complaint. Computerized tomography scan of the neck and chest were obtained before the operation in 71 patients (95%). Ten patients (13%) had a previous partial thyroidectomy. A cervical approach was used in 68 patients (91%). Seven patients (9%) required median sternotomy to complete the operation. One patient (1.3%) died from postoperative respiratory failure. Transient recurrent laryngeal nerve palsy occurred in 5 patients (7%) and permanent RLNP[1] in 3 (4%). The incidence of transient and permanent hypoparathyroidism was 10% and 2.6% respectively. Sixty-six lesions (88%) were benign and 9 (12%) were malignant.

Conclusions: Choking and dyspnea are the most common presenting symptoms of retrosternal goiter. CT scan is an important component of the preoperative evaluation and operative planning. Surgical removal of the thyroid is the treatment of choice and most patients have symptomatic improvement following the operation. Since a substernal thyroidectomy may be technically different from cervical thyroidectomy, a surgical team familiar with its unique pitfalls should perform the procedure.

Objectives: To evaluate the sensitivity, specificity, accuracy, and positive and negative predictive values of FNAB[1] in cases of a solitary thyroid nodule.

Methods: The preoperative FNAB results of 170 patients who underwent thyroidectomy due to a solitary thyroid nodule were compared retrospectively with the final postoperative pathologic diagnoses.

Results: In cases of a solitary thyroid nodule, FNAB had a sensitivity of 79%, specificity of 98.5%, accuracy of 87%, and positive and negative predictive values of 98.75% and 76.6% respectively. All cases of papillary carcinoma diagnosed by FNAB proved to be malignant on final histology, while 8 of 27 cases of follicular adenoma detected by preoperative FNAB were shown to be malignant on final evaluation of the surgical specimen.

Conclusions: FNAB cytology reduces the incidence of thyroidectomy since this method has excellent specificity and sensitivity and a low rate of false-negative results. It proved to be cost-effective and is recommended as the first tool in the diagnostic workup in patients with thyroid nodules.

Objective: To evaluate the contribution of the sestamibi-SPECT (MIBI) localization, cervical ultrasonography, and intraoperative rapid turbo intact parathormone assay in minimal invasive parathyroidectomy.

Methods: Between August 1999 and March 2004, 146 consecutive hyperthyroid patients were treated using the MIBI and ultrasound for preoperative localization and iPTH[1] measurements for intraoperative assessment.

Results: Parathyroid adenoma was detected in 106 patients, primary hyperplasia in 16, secondary hyperplasia in 16, tertiary hyperplasia in 5 and parathyroid carcinoma in 1 patient. Minimal invasive exploration of the neck was performed in 84 of the 106 patients (79.2%) with an adenoma, and in 17 of them this procedure was performed under local cervical block anesthesia in awake patients. Adenoma was correctly diagnosed by MIBI scan in 74% of the patients, and by ultrasound in 61%. The addition of ultrasonography to MIBI increased the accuracy of adenoma detection to 83%. In 2 of the 146 patients (1.4%) iPTH could not be significantly reduced during the initial surgical procedure. Minimal invasive surgery with minimal morbidity, and avoiding bilateral neck exploration, was achieved in 79.2% of patients with a primary solitary adenoma.

Background: Iodine intake is necessary to maintain normal thyroid function and prevent iodine deficiency disorders. In 1990, a resolution calling for universal salt iodination to eliminate iodine deficiency worldwide was taken by the World Health Organization and endorsed by some 130 countries. As of today, very little is known about iodine intake and the prevalence of iodine deficiency disorders in Israel, and iodine enrichment of regular salt has not been authorized.

Objectives: To assess the current level of iodine intake in an unselected group of residents from the Israeli costal area.

Methods: Spot urine samples were collected from three groups: Group A comprising 51 pregnant women attending the Women s Health Clinic at our institution, with a mean age of 32 years and at gestational week 28; group B consisting of 35 healthy subjects, mean age 38; and group C consisting of 16 euthyroid subjects harboring nodular goiters. Tap drinking and mineral water were also analyzed for iodine content. Iodine concentration was measured using the catalytic reduction of ceric ammonium sulfate method.

Results: When considering all groups together the median urinary iodine concentration was 143 µg/L, with 27% of the study population having concentrations under 100 µg/L and 7.8% under 50 µg/L. Values were distributed similarly between sites of residency, and no significant differences were seen between groups. The mean iodine concentration for tap drinking water was 22.8 µg/L (range 0.5–53.5 µg/L) and for mineral water 7 µg/L (range 0–15 µg/L).

Conclusions: Overall, iodine intake appeared to be satisfactory in our study population, however mild deficiency may exist in up to 26% of this group. A nationwide survey is needed to better determine the status of iodine intake in Israel, allowing for recommendations on salt-iodine enrichment in the future.

Background: Among the various new technologies in the field of parathyroid surgery are intraoperative quick parathormone measurements.

Objectives: To evaluate the contribution of QPTH[1] measurements during parathyroidectomy to the achievement of higher success rates. 

Methods: QPTH assay using Immulite Turbo Intact PTH[2] was measured in 32 patients undergoing parathyroidectomy: 30 for primary and 2 for secondary hyperparathyroidism.  QPTH levels were measured at time 0 minutes (before incision) and at 10, 20, and 30 minutes after excision of the hyperfunctioning gland.  Only a drop of 60% or more from the 0’ level was considered to be a positive result.

Results: The mean QPTH level at time 0’ for PHPT[3] patients was 38.12 ± 25.15 pmol/L (range 9.1–118 pmol/L).  At 10 minutes post-excision of the hyperfunctioning gland (or glands), QPTH dropped by a mean of 73.80% to 9.89 ± 18.78 pmol/L. 

Conclusions: Intraoperative QPTH level measurement is helpful in parathyroid surgery.  A drop of 60% or more from 0’ level indicates a successful procedure, and further exploration should be avoided.

Background: Technetium-99m sestamibi scintigraphy has become one of the most popular techniques for localization of the parathyroid gland after failure of primary neck exploration.

Objective: To examine the efficacy of sestamibi with the hand-held gamma ray detecting probe for the identification of parathyroid adenomas during revision parathyroidectomy.

Methods: We reviewed six cases of probe-assisted neck exploration for parathyroid lesions following unsuccessful primary exploration.

Results: In all cases, the pathologic glands were successfully detected and removed.

Conclusions: With careful planning, a gamma ray detecting probe can be used optimally at 2–3 hours after technetium-99m sestamibi injection. The probe is efficient, easy and convenient to use.
 

Background: Primary hyperparathyroidism in elderly patients is usually associated with additional co-morbidity that increases operative risk, and thus many geriatric patients are denied the benefit of surgery for a single parathyroid adenoma.

Objectives:  To evaluate the safety and efficacy of accurate single photon emission computed tomography sestamibi scintigraphy, enabling precise localization of a single adenoma, in the geriatric population

Methods: Twenty-two patients aged 70 years and over with biochemically proven PHPT[1] and with a single parathyroid adenoma identified by localization studies (sestamibi SPECT[2] scan and ultrasonography) underwent 23 operations over 29 months (out of a total of 140 patients operated upon during the same period). Immediate preoperative sestamibi scintigraphy and marking of focal adenoma uptake followed by intraoperative hand-held gamma probe were used for the removal of the parathyroid adenoma by unilateral minimal access surgery. Associated major co-morbid conditions and pre- and postoperative calcium, phosphorus and parathormone levels were recorded. Indications for surgery were listed and operative and postoperative complications were noted. The patients were followed for a mean period of 17.7 months using the same parameters.

Results: The 22 patients with PHPT had a mean age of 76.3 ± 5.9 years (range 70–88 years)  and a female to male ratio of 13:9. Associated co-morbidity included ischemic heart disease (n=15), hypertension (n=22), non-insulin-dependent diabetes mellitus (n=9), chronic obstructive pulmonary disease (n=3), and previous neck surgery (n=3). Mean preoperative serum calcium, phosphorous and PTH[3] were 11.7 ± 1.3 mg/dl, 2.5 ± 0.5 mg/dl and 160.9 ± 75.4 pg/ml respectively. In 20 of the 22 patients, surgery was successful in curing PHPT (91%). One patient had persistent hypercalcemia due to a missed adenoma, and repeat operation (by focused minimal access surgery) was successfully performed 2 weeks later. There were no complications and no morbidity postoperatively. Mean postoperative serum calcium, phosphorous and PTH were 9.6 ± 1.2 mg/dl, 3.0 ± 0.5 mg/dl and 35.2 ± 24 pg/ml respectively. In all patients, serum calcium levels remained normal (9.7 ± 1.3 mg/ml) after long-term follow-up (mean 17.7 ± 9.6 months).

Conclusions: Minimally invasive, radio-guided focused parathyroidectomy for a single adenoma is a safe and effective method to cure hyperparathyroidism in the elderly. Success of surgery is directly related to the surgeon's experience and to the precise localization marking provided by sestamibi scintigraphic SPECT localization and concurrent sonographic findings.