Mahmoud F. Sakr - Parathyroid Gland Disorders: Controversies and Debates

This Springer imprint is published by the registered company Springer Nature Switzerland AG

The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

In this authored book, we aim at emphasizing established concepts, displaying the ongoing arguments, controversies, challenges, and debates on diagnosis and treatment of different parathyroid gland disorders with a view of clarifying some uncertainties, making suggestions to resolve others, and establishing strategies to reach therapeutic success.

This book, with 107 images and 1673 references, will provide a valuable source of knowledge and reference for all specialists and trainees entrusted with the care of patients suffering from parathyroid gland diseases. It includes 18 chapters, namely, historical review, embryology of the parathyroid gland, surgical anatomy of the parathyroid gland, histology of the parathyroid gland, physiology of the parathyroid gland, calcium: why is it important?, hyperparathyroidism (HPT), osteitis fibrosa cystica, hypothyroidism, metabolic syndromes of parathyroid failure, hungry bone syndrome, post-thyroidectomy hypocalcemia (incidence and risk factors, clinical presentation, prevention), parathyroid transplantation, parathyroid cancer, intra-operative tools in parathyroidectomy, and parathyroidectomy.

It is my collective hope that head and neck surgeons, dentists, maxillofacial surgeons, orthopedic surgeons, endocrinologists, oncologists, pediatricians, and clinicians of other specialties will find this book to be a useful and indispensable resource as they face the most challenging of parathyroid gland disorders to help provide individual patients with the best possible outcome.

I would like to thank all those who helped and encouraged me during the writing, editing, and revision of this book. I would like to express my appreciation and gratitude to my wife and children for their continuous support and unconditioned love.

Because of their unique anatomical features, the parathyroid glands (PTGs) were the last of the endocrine glands to be discovered, which greatly hindered proper treatment until the first decades of the twentieth century. Identification of the PTGs, recognition of their important role, and understanding of the diseases that affect them traveled a long journey to the present state of knowledge. Technological developments in the last three decades greatly facilitated the location of the PTGs and the conduction of surgery for hyperparathyroidism (HPT). However, an experienced and dedicated surgeon is still essential to the excellence of treatment [].

The parathyroid glands (PTGs) were first discovered in 1852 in , p. 219]. He suggested they were embryonic portions of the thyroid gland.

The famous German pathologist Rudolph Virchow may have identified one PTG in 1863, when he described a structure in the cervical region, emphasizing that it was not an accessory thyroid gland or lymph node, or any other structure that was familiar to him, though showing no interest in the finding as reported by Dubose et al. (2005) in their review of the history of parathyroid surgery [].

The PTGs were first discovered in humans in 1880, by ]. Sandstrm, who received the physician title in 1887, was so disturbed by such lack of recognition of his discovery that he fell into a deep depression, which perhaps may have contributed to his suicide at the age of 37 years.

In 1938, Gilmour published his detailed studies on the gross and histological anatomy of the PTGs, but the unusual location of the glands was first noted in surgical patients by Gaz in 1987 as reported by Skandalakis et al. in 2004 [].

The term tetany describes a set of neuro-muscular symptoms caused by nervous system hyper-excitability, which can vary from peri-oral paresthesias to cramps and muscle stiffness [].

Advances in general anesthesia (1840s) and understanding the importance of antisepsis (1860s) and hemostasis (1870s) allowed the beginning of the first successful operations on the thyroid gland in the following decades. The high mortality rate (over 40%) faced by surgeons of the time began to reduce, mainly by the work of two remarkable surgeons in this area: Theodor Kocher and Theodor Billroth. Patients operated upon by Kocher developed hypothyroidism post-operatively, while those operated upon by Billroth, rarely developed hypothyroidism post-operatively; however, many developed severe tetany with a fatal outcome. William Halsted, after watching operations of the great masters, found that the difference was probably related to the technique. Kocher was extremely meticulous and precise, operating carefully with strict hemostasis. He removed the entire thyroid gland and his patients rarely suffered voice changes or tetany due to preservation of the recurrent laryngeal nerve (RLN) and PTGs. Billroth, in contrast, worked quickly, with less rigorous hemostasis, which probably increased the risk of PTG removal, and the remaining thyroid tissue prevented severe hypothyroidism. For his contributions to thyroid gland physiology, pathology, and surgery, Kocher received the Nobel Prize in 1909.