scholarly journals Thyroid fibrous band and levator glandulae thyroideae muscle: Two different structures associated with the pyramidal lobe of the thyroid gland

2021 ◽  
Vol 73 (1) ◽  
pp. 73-81
Author(s):  
Bojan Milojevic ◽  
Vladan Zivaljevic ◽  
Ivan Paunovic ◽  
Aleksandar Malikovic

We investigated two structures that are in close association with the pyramidal lobe of the thyroid gland. Our investigation was performed using microdissection and histological examination in 106 human postmortem specimens. The first investigated structure was identified as the thyroid fibrous band that was present in 28.3% of cases. This band was always associated with the pyramidal lobe (which was significantly longer and thicker when associated with this band) and it had a constant hyo-pyramidal extension; it was located close to the midsagittal plane and predominantly composed of dense irregular connective tissue. The second investigated structure was the levator glandulae thyroideae muscle, which was associated with the pyramidal lobe in only 13.6% of cases. This muscle had a double extension, hyo-pyramidal and laryngo-pyramidal, located farther from the midsagittal plane, it was longer and thinner than the thyroid fibrous band and predominantly composed of striated muscle fibers. We confirmed our hypothesis that the thyroid fibrous band, which may be considered as the partial fibrous remnant of the thyroglossal duct and levator glandulae thyroideae, and which may be considered as infrahyoid or laryngeal muscle, are two different structures of the thyroid gland.

2015 ◽  
Vol 197 ◽  
pp. 29-37 ◽  
Author(s):  
Yoshitaka Takanashi ◽  
Yohei Honkura ◽  
Jose Francisco Rodriguez-Vazquez ◽  
Gen Murakami ◽  
Tetsuaki Kawase ◽  
...  

1980 ◽  
Vol 52 (4) ◽  
pp. 564-569 ◽  
Author(s):  
John W. Walsh ◽  
William R. Markesbery

✓ A study of 20 children with lipomyelomeningocele and two with intradural lipoma who underwent surgery revealed that five children had unusual and previously unreported histological findings. In each, the characteristic densely fibrous lipoma was present. One patient with an intradural lipoma had an ependymallined canal resembling a terminal ventricle. The subependymal layer was neuroglial and striated muscle fibers were scattered throughout adjacent connective tissue and lipoma. Three other children presented with lipomyelomeningoceles. In each case, the lipoma tapered to a firm fibrous tract which blended into conus medullaris. Microscopic examination of this fibrous tract showed it to contain not only a relatively acellular connective tissue stroma, but, in one case, sheets or islands of neuroglia and scattered nerve cells, in another, an epithelial cyst with a smooth muscle and fibrous tissue wall, and in a third case, a fragment of embryonic bone. These findings support the theory that there is a secondary phase to caudal neural tube development, and that congenital lipomas are formed by persistence and differentiation of ordinarily vestigial pluripotential embryonic cells. The fifth case, with extradural lipoma, diastematomyelia, and congenital dermal sinus, had a cyst at the junction of these structures. The cyst was lined by ciliated respiratory-like epithelium, and had mucous and serous glands in its wall. This finding supports the concept that formation of diastematomyelia depends on the prior existence of an accessory neurenteric canal.


2017 ◽  
pp. 19-23
Author(s):  
Muhammad Iqbal ◽  
Muhammad Naeem ◽  
Muhammad Imran ◽  
Muhammad Akhtar

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1652.1-1652
Author(s):  
A. Pandey ◽  
V. Ravindran ◽  
M. Pandey ◽  
R. Rajak ◽  
V. Pandey

Background:A close association between periodontal disease and Ankylosing spondylitis (AS) has long been specualted. Both diseases are characterized by dysregulation of the host inflammatory response, leading to further destruction of soft and hard connective tissue with there being evidence of increased levels of TNF-α and various interleukins in both patients of AS and periodontitis.Objectives:The aim of this systematic review was to appraise the available literature exploring the relationship between AS and periodontal disease.Methods:We searched Medline & Embase databases (from their inception till October 2019) using appropriate combinations of following search items with limits ‘(English, Human)’; Ankylosing spondylitis, spondyloarthritis, spondyloarthropathies, spondyloarthritides, spinal disease, musculoskeletal disease, Rheumatic disease AND periodontitis, periodontal disease, periodontoses, parodontoses, chronic periodontitis, gum disease, gingivitis, oral health, dental health, plaque index, bleeding on probing, probing pocket depth, clinical attachment loss. This search was supplemented by the manual search of bibliographies of articles selected and conferences proceedings of EULAR. Only be reviews, observational study of cross-sectional, cohort or case control type on adult patients with AS were selected. Data was extracted from a predesigned proforma. A close association between periodontal disease and Ankylosing spondylitis (AS) has long been specualted. Both diseases are characterized by dysregulation of the host inflammatory response, leading to further destruction of soft and hard connective tissue with there being evidence of increased levels of TNF-α and various interleukins in both patients of AS and periodontitis.Results:A total number of 984 articles were identified and 12 were selcted for detailed appraisal (Figure 1, PRISMA flow chart). They were all case control studies. The prevalence of periodontitis ranged from 38% to 88% in patients with AS whereas in the control group from 26% to 71 % in controls. Out of 12 studies, two showed significant changes in Plaque Index (PI), two studies showed altered Pocket Probing Depth (PPD), three showed significant increased in Clinical Attachment Loss (CAL) and increased Bleeding On Probing (BOP) was seen in 2 studies. In 7 studies, periodontitis was seen in a significant number of patients with AS (P<0.05). All studies reported that the prevalence of periodontal disease in AS patients was higher as compared to non-AS patients.Conclusion:Our systematic review found an association between AS and periodontal disease. Patients with AS show higher prevalence of periodontitis and a poor oral hygiene as compared to healthy controls. At practice level, this systematic review underscores the need for a collaboration between dentists and rheumatologist.Disclosure of Interests:None declared


2021 ◽  
Vol 37 (1) ◽  
Author(s):  
Inès Riahi ◽  
Rim Fradi ◽  
Ibtissem Ben Nacef ◽  
Ahlem Blel

Abstract Background Ectopic thyroid is a developmental anomaly of the thyroid gland of embryological origin. Instead of having a pretracheal situation, thyroid tissue is elsewhere, most commonly in the median cervical line along the course of the thyroglossal duct. Lingual thyroid is the most common presentation. Ectopic thyroid tissue in the submandibular region has been rarely reported. Case presentation We report herein a case of a 65-year-old man admitted to our department with a complaint of a painless swelling in the left submandibular region. Conclusions Thyroid gland ectopia should be considered among the differential diagnoses of submandibular swelling. Ectopic thyroid tissue can present with the same pathology affecting the normal thyroid gland such as malignancy and hyperthyroidism.


2014 ◽  
Vol 6 (3) ◽  
pp. 110-112 ◽  
Author(s):  
R Fernando ◽  
Anuradha Rajapaksha ◽  
Narada Ranasinghe ◽  
Duminda Gunawardana

ABSTRACT Thyroid gland has three main embryological remnants: pyramidal lobe, tubercle of Zuckerkandl and thyrothymic remnants. They are commonly missed or misidentified during dissection. Each of these remnants plays a critical role in thyroidectomy as they help to identify the relevant anatomy and therefore help prevent accidental damage to other structures in close proximity during dissection. In this article, we describe the current knowledge of each of these remnants and their significance in thyroidectomy. Conclusion It is important that all these remnants are objectively looked for and removed during surgery in order to prevent recurrences. How to cite this article Fernando R, Rajapaksha A, Ranasinghe N, Gunawardana D. Embryological Remnants of the Thyroid Gland and their Significance in Thyroidectomy. World J Endoc Surg 2014;6(3):110-112.


1967 ◽  
Vol 7 (3) ◽  
pp. 499-504 ◽  
Author(s):  
BENJAMIN WALCOTT ◽  
ELLIS B. RIDGWAY

Author(s):  
Ildiko Lingvay ◽  
Shelby A. Holt

The thyroid gland, which is the largest endocrine organ, secretes primarily thyroid hormones that play a critical role in the normal growth and development of the maturing human. In the adult, thyroid hormones maintain metabolic stability by regulating oxygen requirements, body weight, and intermediary metabolism. Thyroid function is under hypothalamic-pituitary control, and thus, like the gonads and adrenal cortex, it serves as a classical model of endocrine physiology. In addition, the physiological effects of thyroid hormones are regulated by complex extrathyroidal mechanisms resulting from the peripheral metabolism of the hormones, mechanisms that are not under hypothalamic-pituitary regulation. Thyroid function abnormalities are very prevalent, especially in females and in certain geographic areas, and are often a result of autoimmunity or iodine deficiency. The thyroid originates from two distinct parts of the embryonic endoderm: • The follicular structures arise from a midline thickening of the anterior pharyngeal floor (the base of the tongue), adjacent to the differentiating heart. This thyroid diverticulum first expands ventrally while still attached to the pharyngeal floor by its stalk (thyroglossal duct), and then expands laterally, leading to the characteristic bilobed structure. As the developing heart descends, the thyroid gets pulled into its final position, a process that leads to the rapid stretch and degeneration of the thyroglossal duct. • The parafollicular cells are derived from the ultimobranchial bodies (originating from the neural crest) but ultimately are surrounded by the medial thyroid. The parafollicular cells represents <10 % of the adult thyroid gland. The thyroid completes its structural development by 9 weeks of gestation, the first endocrine organ to assume its definitive form during organogenesis; yet full functional maturation and integration with the hypothalamic-pituitary axis continues throughout gestation. Abnormal thyroid development can lead to persistence of the thyroglossal duct, presence of ectopic thyroid tissue (lingual thyroid, lateral aberrant thyroid), and malposition (thoracic goiter), all of which can remain clinically silent or present later in life as diagnostic challenges. The shape of the human thyroid resembles that of a butterfly.


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