The Relationship of Intraoperative Identification of Parathyroid Glands to Postoperative Hypoparathyroidism after Total Thyroidectomy for Cancer

Background: Until recently, the knowledge of the anatomical variations in the relationship between the recurrent laryngeal nerve (RLN) and the inferior thyroid artery (ITA) combined with visual intraoperative RLN identification are essential for the protection of these life-important structures during surgical exposure and the mobilization of thyroid and parathyroid glands. This leads to the proper treatment of patients and improvement of the surgical techniques.Aim: To describe anatomical variations in the relationship of the recurrent laryngeal nerve to the inferior thyroid artery in the Sudanese population.Patients and methods: Following ethical committee approval, an observational descriptive prospective cross-sectional study in the period between March 2019 and February 2020, for anatomical variations in the relation of the recurrent laryngeal nerve to the inferior thyroid artery in seventy-two cervical sides of thirty-six well-dissected embalmed Sudanese cadavers. The RLN was investigated in three positions: posterior to the ITA main trunk, anterior to the ITA main trunk and between the ITA branches. Then, the results were analyzed according to the gender, age and dissection side.Results: We found that the anatomical variations were more frequent in males (97.2%) than females (2.8%). The age of these variations ranged between 31–45 years which represents (61.1%). On the right side of the neck, the commonest position of the RLN is posterior to the ITA (63.9%) followed by in decreasing order of frequency, the RLNs run between the ITA branches (30.6%) and anterior to the ITA (5.6%). On the left side of the neck, the commonest position of the RLN is posterior to the ITA (69.4%). It passed between the ITA branches in (30.6%) of specimens. There was no anterior location of the RLN to the ITA. Variations in a relationship of the RLN to the ITA on one side is significantly different from the opposite side.Conclusions: Although the risk of potential damage to the RLN during surgical neck procedures involving the thyroid gland and parathyroid glands is well recognized, pre-operative detailed surgeon’s knowledge for these frequent anatomical variations and the usage of the ITA as an anatomical landmark for intraoperative RLN recognition is important. This will lead to a reduction of iatrogenic RLN injury prevalence. Future studies are recommended to compare the findings on this cadaveric study with a larger sample size in the long-term period.

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Measurement of serum intact parathyroid hormone (iPTH) at the end of total thyroidectomy: A reliable parameter for hypocalcemia?

British Journal of Surgery ◽

10.1093/bjs/znab202.033 ◽

2021 ◽

Vol 108 (Supplement_4) ◽

Author(s):

A Lalos ◽

K Linke ◽

M von Flüe ◽

B Kern

Keyword(s):

Parathyroid Hormone ◽

Total Thyroidectomy ◽

Clinical Symptoms ◽

Parathyroid Tissue ◽

Postoperative Management ◽

Parathyroid Glands ◽

Intact Parathyroid Hormone ◽

Postoperative Hypoparathyroidism ◽

Symptomatic Hypocalcemia ◽

The Mean

Abstract Objective Total thyroidectomy represents the gold standard surgical procedure for patients with malignant thyroid disease. Over the past decades, the total thyroidectomy gradually replaced the subtotal thyroidectomy for benign thyroid disorders as well. Postoperative hypocalcemia remains the most frequent complication. The close proximity of parathyroid glands to the thyroid capsule leads often to devascularization or adventitious removal of parathyroid tissue. Clinical symptoms like paresthesia, tingling, muscle cramps or seizures often occur. Combined measurement of intact parathyroid hormone (iPTH) and calcium after the operation are used worldwide to predict postoperative hypoparathyroidism. The purpose of this study was to find out the incidence of decreased iPTH at the end of surgery and its reliability in predicting hypocalcemia. Methods We performed a retrospective analysis of 534 patients who underwent total thyroidectomy at our institution between 2000 and 2019. Medical records were reviewed to analyze the patient characteristics, indication of the procedure, laboratory and histological results, postoperative management and complications. The iPTH was measured before and at the end of the surgery, while the calcium was measured at the first postoperative day. The iPTH assay at our hospital has a normal range between 15.0 and 80.0 pg/ml. Meanwhile hypocalcemia was defined as a calcium measurement < 2.2 mmol/l. Results The mean age of the patients was 55.34 years. The female to male ratio was 4.6:1. The mean preoperative iPTH of our cohort was 48.35 pg/ml, while the postoperative iPTH was 31.74 pg/ml, indicating a mean reduction of 35.75%. A total of 174 patients (32.6%) had a iPTH < 15.0 pg/ml at the end of the surgery, indicating a reduction of 75.6%. 22 of these 174 patients (12.6%) developed clinical symptoms of hypocalcemia. In contrast only 3 patients (0.08%) with normal iPTH developed symptoms. Whole parathyroid glands were identified in 95/534 (17.8%), whereas from the 174 patients with iPTH < 15.0 pg/ml, 56 (32.2%) had at least one parathyroid gland in the operative specimens. Conclusion Measurement of iPTH at the end of total thyroidectomy is a good predictor to detect patient who are at risk for developing symptomatic hypocalcemia and calcium substitution can be started at the same day. A normal iPTH almost excludes symptomatic hypocalcemia.

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Association between number of parathyroid glands identified during total thyroidectomy and functional parathyroid preservation

Langenbeck s Archives of Surgery ◽

10.1007/s00423-021-02287-6 ◽

2021 ◽

Author(s):

Fiona Riordan ◽

Matthew S. Murphy ◽

Linda Feeley ◽

Patrick Sheahan

Keyword(s):

Vitamin D ◽

Multivariate Analysis ◽

Total Thyroidectomy ◽

Parathyroid Glands ◽

Graves Disease ◽

Permanent Hypoparathyroidism ◽

Academic Teaching ◽

Postoperative Hypoparathyroidism ◽

Academic Teaching Hospital ◽

Systematic Identification

Abstract Purpose Systematic identification of all 4 parathyroid glands has been recommended during total thyroidectomy (TT); however, it is unclear whether this strategy necessarily translates into optimized functional parathyroid preservation. We wished to investigate the association between number of parathyroids identified intraoperatively during TT, and incidence of incidental parathyroidectomy, and postoperative hypoparathyroidism. Methods Retrospective review of prospectively maintained database of 511 consecutive patients undergoing TT at an academic teaching hospital. The association between number of parathyroid glands identified intraoperatively and incidence of biochemical hypocalcaemia (defined as any calcium < 2 mmol/L n first 48 h after surgery), symptomatic hypocalcaemia; permanent hypoparathyroidism (defined as any hypocalcaemia or need for calcium or vitamin D > 6 months after surgery), and incidental parathyroidectomy, was investigated. The association between number of parathyroid glands visualized and postoperative parathyroid hormone (PTH) levels was investigated in a subset of 454 patients. Results Patients in whom a greater number of parathyroids had been identified had a significantly higher incidence of biochemical and symptomatic hypocalcaemia, and significantly lower postoperative PTH levels, than patients with fewer glands identified. There were no significant differences in incidence of permanent hypoparathyroidism or incidental parathyroidectomy. On multivariate analysis, malignancy, Graves disease, and identification of 3–4 parathyroids were independent predictors of biochemical hypocalcaemia. For symptomatic hypocalcaemia, identification of 2–4 parathyroids, and identification of 3–4 parathyroids, were significant. Conclusions Systematic identification of as many parathyroid glands as possible during TT is not necessary for functional parathyroid preservation.

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THE RELATIONSHIP OF THE PARATHYROID GLANDS TO THE ACTION OF ESTROGEN ON BONE

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1946.147.3.522 ◽

1946 ◽

Vol 147 (3) ◽

pp. 522-526 ◽

Cited By ~ 7

Author(s):

Burton L. Baker ◽

Joseph H. Leek

Keyword(s):

Parathyroid Glands ◽

Relationship Of ◽

The Relationship

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Acid Phosphatase Activity in Mammalian Parathyroid Glands

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066632 ◽

1971 ◽

Vol 29 ◽

pp. 516-517

Author(s):

W. Allen Shannon ◽

Sanford I. Roth

Keyword(s):

Enzymatic Activity ◽

Cell Membranes ◽

Secretory Granules ◽

Basement Membranes ◽

Parathyroid Glands ◽

Capillary Endothelium ◽

Golgi Membranes ◽

Parenchymal Cells ◽

Relationship Of ◽

The Relationship

It has been suggested that the parathyroid secretory granules might represent lysosomes. Since lysosomes are known to contain acid phosphatases (AcPase), this enzymatic activity was investigated with a modified Gomori lead method with β-glycerophosphate as the substrate to determine the relationship of secretory granules to lysosomes in adenomatous and hyperplastic (primary chief cell type) human, and normal bovine, human, and rat parathyroid glands.Intracellular activity was demonstrated in the lipofuchsin granules and in rare, membrane-limited bodies consistent with lysosomes (Figs. 1 and 2). These lysosomal granules were often irregular in shape and 450 to 850 mμ in diameter. Lead precipitate was also observed in association with some Golgi membranes and cisternae and in a few small Golgi vesicles (Fig.3). There was strong AcPase reactivity in the lumenal cell membranes of the capillary endothelium (Fig. 4) though the cell membranes adjacent to the basement membranes and those of the parathyroid parenchymal cells were devoid of enzymatic activity. No activity was present in the numerous small secretory granules or in the granular endoplasmic reticulum (Figs. 1 and 2).

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Studies on Leukemogenic and Sarcomagenic Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067777 ◽

1970 ◽

Vol 28 ◽

pp. 156-157

Author(s):

Leon Dmochowski

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Morphological Properties ◽

Mode Of Development ◽

Relationship Of ◽

The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

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The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085484 ◽

1991 ◽

Vol 49 ◽

pp. 236-237

Author(s):

J.R. Pfeiffer ◽

J.C. Seagrave ◽

C. Wofsy ◽

J.M. Oliver

Keyword(s):

Mast Cells ◽

Protein A ◽

Scattered Electron ◽

Ige Receptor ◽

Receptor Complexes ◽

Ige Binding ◽

Electron Imaging ◽

Small Clusters ◽

Relationship Of ◽

The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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