Carcinoma in thyroglossal duct remnants

Two cases of carcinoma arising in thyroglossal duct remnants are reported to add to the previously documented 78 cases in the literature. This rare lesion, which occurs is less than 1% of thyroglossal duct abnormalities, pathologically and clinically is similar to primary tumors arising in the thyroid gland. Papillary adenocarcinomas constitute 75-85% of all cases reported and most are confined to the duct remnant itself with metastasis being infrequently recorded. Therapy consists of wide excision of the tumor-bearing tissue (Sistrunk procedure) in those cases localized to the duct remnant itself. In instances where metastasis or additional lesions are detected in the thyroid gland, thyroid ablation and neck dissections are indicated. Additional modalities such as suppressive thyroid therapy, radioactive iodine, and external radiation have been employed. Distant metastasis is rare and the long-term prognosis is very favorable.     

Carcinoma arising in thyroglossal remnants

Three patients with a papillary carcinoma arising in a thyroglossal duct cyst are presented and the literature is reviewed. This rare malignancy is seen mostly in women between the ages of 20 and 50 years. The distribution of carcinoma subtypes differs from that of thyroid carcinomas and thyroglossal duct carcinoma is recognized as a primary tumour. The diagnosis is seldom made pre-operatively though especially in older patients with midline swellings in the neck the diagnosis should be considered. Sistrunk's operation is the treatment of choice. In this operation the cyst, the middle part of the hyoid bone and the thyroglossal duct are removed in continuity.     

Papillary carcinoma in thyroglossal duct remnants

Summary About 100 cases of carcinoma arising in thyroglossal remnants have been reported in the world literature. Five additional cases were discovered incidentally on histopathological examinations of specimens following Sistrunk's operation for removal of thyroglossal cysts and are now reported. The possibility of preoperative clinical diagnosis and the modalities of treatment are discussed. Offprint requests to: L. Pacheco-Ojeda     

Risk factors for thyroglossal duct remnants after Sistrunk procedure in a pediatric population

To evaluate recurrence after surgery for thyroglossal duct cyst (TDC) we performed a retrospective chart review. Seventy four patients between 0.5 and 8.5 years of age presenting with a midline neck cyst underwent a Sistrunk procedure for a preoperative diagnosis of TDC. Fifty-seven had histologically confirmed TDC (mean age of the population: 4+/-1.5 years, mean follow-up: 6 years and 8 months). Recurrence occurred in 15% of the cases of histologically confirmed TDC. Four individual risk factors have been identified: number of infection before surgery [more than 2 episodes (P<0.05)]; preliminary surgical procedure (P<0.05); age [less than 2 years (P<0.05)] and multicystic lesion on histopathology (P<0.01). The two first factors being correlated, the risk of relapse might be lowered by a wide excision performed before any infection in children over 2 years.     

Auto-immune thyroiditis presenting as a thyroglossal tract swelling

Both thyroglossal cysts and aberrant thyroid tissue may present as a mid-line neck swelling. We report a case of autoimmune thyroiditis presenting as a thyroglossal swelling in a middle-aged woman. This very rare finding is discussed with reference to the optimal management of thyroglossal tract swellings.     

Management of thyroglossal tract disease after failed Sistrunk's procedure

Sistrunk's procedure for thyroglossal duct remnants has a very high success rate, there remains the occasional patient, however, that will have recurrent disease despite a competently performed operation. Applied anatomy and embryology proffer a solution to this problem. Extending the Sistrunk operation, with an anterior wide local excision remaining within normal tissue, enables removal of the entire thyroglossal tract remnant. A retrospective case note review was conducted to study our experience using this extended procedure to treat patients with thyroglossal tract disease that had recurred after a previous Sistrunk's operation. Six patients aged from five to 33 years were included in the study. There was one recurrence and the complication rate was comparable to the standard operation. It was concluded that a wide local excision is a valuable extension of the Sistrunk operation for the management of recurrent disease.     

The applied anatomy of the anterior commissure and subglottis.

The applied anatomy of the subglottis and anterior commissure is discussed and an attempt made to correlate the histological anatomy with that clinically accessible. It is suggested that although the undersurface of the vocal fold is classified as part of the glottis by the 1972 UICC and AJC staging system, it should be considered as the roof of the subglottis. The anterior commissure, which is probably a small site within the glottis rather than a true area, is histologically difficult to separate from the anterior subglottis. The characteristic microvasculature of the anterior commissure is presented as being possibly relevant to the mode of spread of tumors at this site.     

Histological characterization of the thyroglossal tract: implications for surgical management

OBJECTIVES: In the current report, we characterized the relationship between the central hyoid bone and the thyroglossal tract and determined the prevalence of ectopic thyroid follicles in the adjacent soft tissues. STUDY DESIGN: Retrospective pathological analysis. METHODS: The resected specimens from 104 patients who underwent a modified Sistrunk procedure with wide-field dissection were retrospectively analyzed. Under light microscopy, serial sections were examined to determine whether the thyroglossal tract passed anterior to, posterior to, or within the hyoid bone. Specimens were also examined for the presence of thyroid follicles in the periductal and pericystic soft tissues. RESULTS: In 50 cases (48%), the tract position in relation to the hyoid bone could not be identified secondary to extensive arborization, marked inflammation, specimen fragmentation or a combination of these. Thyroid follicles were observed in 9 (18%) of these specimens. In the remaining 54 cases (52%) the tract was located anterior to the central arch of the hyoid bone in 39 (72%) and posterior to it in 15 (28%). Thyroid tissue was observed in 46% of specimens (P =.004), regardless of whether the tract was anterior or posterior. CONCLUSIONS: These results demonstrate that tract position often cannot be defined, but when a portion is dominant, it is likely to be anterior to the hyoid bone. Ectopic thyroid tissue can be found in almost 50% of specimens when the tract position is identifiable. With appropriate surgical management, a recurrence rate of less than 4% can be expected, despite the presence of ductule multiplicity, marked inflammation, tract position posterior to the hyoid bone, and ectopic thyroid follicles.     

犬喉移植的应用解剖学研究

观察有关犬喉的颈部肌肉，喉的主要供血来源和回流静脉、分析犬喉血液循环的主要通道，测量相关血和的管径，以探讨吻合血管的选择，设计喉再植或移植的血管吻合方式。提出两侧颈总动脉颅甲动脉及颈外静脉的颅喉静脉，喉奇静脉是犬喉血液循环的主要通道，移植时可选择带有颅甲动脉的颈总动脉和两侧的颈外静脉作为吻合血管，单一颅甲动脉可以维持犬喉的血供。     

影响胆脂瘤残留因素的探讨

为了探讨影响慢性中耳炎乳突根治术后胆脂瘤残留的因素，对我院1985～1996年间319例乳突根治术后再根治的资料进行了分析。发现年龄、胆脂瘤基质的浸润、鳞状上皮清除不彻底、中耳乳突内裂隙的存在等均是影响慢性中耳炎乳突根治术后胆脂瘤复发的重要因素。     

颏下动脉二腹肌前腹为蒂下颌骨膜瓣的解剖

目的为应用颏下动脉二腹肌前腹为蒂的下颌骨骨膜瓣转位修复喉、气管提供解剖学依据。方法对２３例（４６侧）头颈部标本的颏下动脉、颏下静脉、二腹肌前腹的相关结构进行观测。结果颏下动脉为面动脉的恒定分支,走行于下颌下腺与下颌骨下缘之间,恒定分支供应二腹肌前腹和下颌骨骨膜,并与对侧有广泛的吻合支。二腹肌前腹以３０°角附着于骨膜,肌腹横截面积明显小于附着的骨膜面积。结论带颏下动脉二腹肌前腹蒂的下颌骨膜瓣有转移范围大、血供丰富、应用灵活等优点。颏下动脉二腹肌前腹为蒂的下颌骨膜瓣修复喉气管具有可行性。     

影响胆脂瘤残瘤因素的探讨

为了探讨影响慢性中耳炎乳突根治术后胆脂瘤残瘤的因素，对我院１９８５￣１９９６年间３１９例乳突根治术后再根治的资料进行了分析。发现年龄、胆脂瘤基质的浸润、鳞状上皮清除不彻底、中耳乳突内裂隙的存在等均是影响慢性中耳炎乳突奶治术后胆脂瘤复发的重要因素。