Advances in the application of auxiliary imaging techniques in parathyroid diseases

Hypoparathyroidism is one of the main complications after total thyroidectomy,severely affecting patients’quality of life.How to effectively protect parathyroid function after surgery and reduce the incidence of hypoparathyroidism has always been a key research area in thyroid surgery.Therefore,precise localization of parathyroid glands during surgery,effective imaging,and accurate surgical resection have become hot topics of concern for thyroid surgeons.In response to this clinical phenomenon,this study compared several different imaging methods for parathyroid surgery,including nanocarbon,indocyanine green,near-infrared imaging techniques,and technetium-99m methoxyisobutylisonitrile combined with gamma probe imaging technology.The advantages and disadvantages of each method were analyzed,providing scientific recommendations for future parathyroid imaging.In recent years,some related basic and clinical research has also been conducted in thyroid surgery.This article reviewed relevant literature and provided an overview of the practical application progress of various imaging techniques in parathyroid surgery.

The Role of Preoperative Ultrasound and Sestamibi Scintigraphy in the Surgical Management of Primary Hyperparathyroidism: A Review of Literature

Background: Primary hyperparathyroidism (pHPT) is one of the most common endocrine diseases and the most common cause of hypercalcemia. Since routine laboratory testing, the prevalence of the disease has increased from 0.1% to 0.4% worldwide. The only curative treatment is parathyroidectomy. Nowadays, preoperative localization studies have become standard before surgical treatment, and the first stage imaging methods are cervical ultrasonography (US) and/or Sestamibi scintigraphy. Objectives: To describe the accuracy of US and Sestamibi for detection of hyperfunctioning parathyroid adenomas preoperatively in patients with confirmed pHPT from our medical institution. Results: This is a retrospective study from a prospectively kept database that included thirty-one patients with the confirmed diagnosis of pHPT clinically and biochemically. The average age was 57.8 years old. Preoperative US and surgery findings were compared with a sensitivity of 51%. Preoperative Sestamibi and surgery findings were compared resulting in a sensitivity of 71%. Both imaging methods combined, resulted in a sensitivity of 80%. Conclusion: In patients with pHPT, Sestamibi is an effective method for localizing parathyroid pathology preoperatively, but the false negative rate can be high. US tends to have a wider range explained by the operator-dependent factor. The combination of US and Sestamibi reduces the rate of false negatives, as reported in international literature. It is important to mention that these studies cannot be used as a confirmatory test for this disease. It should only be used as an adjunct to help plan the operation.

Identification of the Parathyroid Gland with Vasculature by Intraoperative Carbon Nanoparticles

Background: We aimed to investigate the ability of carbon nanoparticles to identify parathyroid glands with vasculature during thyroid surgery. Material and methods: Totally 42 patients with various thyroid diseases were selected for the prospective research of carbon nanoparticle injection used in thyroidectomy. Another 42 patients without receiving carbon nanoparticle injection were selected as the control group. All cases underwent total or subtotal bilateral thyroidectomy. Before the ligation of the superior and inferior poles of the thyriod lobes, 0.1 mL of a carbon nanoparticle suspension was injected into the two poles. Important tissues such as the recurrent laryngeal nerve, parathyroid gland with blood supply and the inferior thyroid artery were identified and protected. Results: The parathyroid glands with vasculature were not stained and thus remained the primary color in all cases, while abnormal thyroid tissues were stained black. After 5 minutes, thyroid lobes were injected with the carbon nanoparticle suspension and the original color of parathyroid glands was unchanged. Even the parathyroids with blood supply can be identified and protected. The number of parathyroid glands for autotransplantation was one in the test group and six in the control group. At one day after the thyroid surgery, hypocalcemia became detectable in four patients of the test group and in five of the control group. Twenty-four instances of hypoparathyroidism occurred at 1 day after surgery in the control group, while ten instances in the test group. Conclusion: Intraoperatvie carbon nanoparticle suspension injection is an effective and safe technique for guiding thyroid surgery. The carbon nanoparticle suspension plays an important role in identifying the vasculatural parathyroid glands, while protecting the physiologic function of the parathyroid glands during surgery.

Routine exposure of recurrent laryngeal nerve in thyroid surgery can prevent nerve injury

To determine the value of dissecting the recurrent laryngeal nerve during thyroid surgery with respect to preventing recurrent laryngeal nerve injury, we retrospectively analyzed clinical data from 5 344 patients undergoing thyroidectomy. Among these cases, 548 underwent dissection of the recurrent laryngeal nerve, while 4 796 did not. There were 12 cases of recurrent laryngeal nerve injury following recurrent laryngeal nerve dissection （injury rate of 2.2%） and 512 cases of recurrenl laryngeal nerve injury in those not undergoing nerve dissection （injury rate of 10.7%）. This difference remained statistically significant between the two groups in terms of type of thyroid disease, type of surgery, and number of surgeries. Among the 548 cases undergoing recurrent laryngeal nerve dissection, 128 developed anatomical variations of the recurrent laryngeal nerve （incidence rate of 23.4%）, but no recurrent laryngeal nerve injury was found. In addition, the incidence of recurrent laryngeal nerve injury was significantly lower in patients with the infedor parathyroid gland and middle thyroid veins used as landmarks for locating the recurrent laryngeal nerve compared with those with the entry of the recurrent laryngeal nerve into the larynx as a landmark. These findings indicate that anatomical variations of the recurrent laryngeal nerve are common, and that dissecting the recurrent laryngeal nerve during thyroid surgery is an effective means of preventing nerve injury.