The Incidence of Thoracic Outlet Syndrome.

BACKGROUND: Thoracic outlet syndrome (TOS) refers to a constellation of compressive problems that occur at the thoracic outlet. TOS has been recognized since the 19th century, and the "modern" era of treatment, especially for neurogenic TOS, dates from at least the 1970s. Despite this, however, the incidence and prevalence of these syndromes are almost completely unknown. To attempt to answer this fundamental question, we established a prospective database of all patients who presented to our clinic with a diagnosis of potential TOS, as described below. METHODS: We established a database of all patients referred to our clinic from July 1, 2014 to May 2018. All subjective data, the tentative diagnosis, and plan at the time of the office visit were prospectively recorded. For patients with neurogenic TOS (NTOS), a standardized workup sheet was used based on the Society for Vascular Surgery's recently published reporting standards document. For patients with venous TOS (VTOS), diagnosis was made by clinical examination and ultrasound, and for those with arterial TOS (ATOS), by clinical examination, ultrasound, and cross-sectional imaging when needed. RESULTS: From July 1, 2014, to May 1, 2018, 526 patients were referred to our institution with a diagnosis of possible TOS. Of these, 432 (82%) were referred with symptoms suggestive of NTOS, 84 (16%) with symptoms suggestive of VTOS, and 10 (2%) with findings and/or symptoms suggestive of ATOS. NTOS: After evaluation as per the algorithm previously mentioned, 234 patients (54%) were judged high suspicion for NTOS, 126 (30%) moderate suspicion, and 72 (17%) low suspicion; 360 (83%) of those originally referred were felt to potentially have NTOS. Of the 84 patients with VTOS, 25 (30%) presented with acute Paget-Schroetter syndrome, 41 (48%) with subacute or chronic occlusion, and 18 (21%) with McCleery's syndrome. Finally, 8 of the 10 limbs had true ATOS; of these, 6 (75%) underwent decompression and repair and 2 (25%) endovascular intervention only. Based on referral assumptions and population density in our area, the incidence of NTOS seems to be between 2 and 3 cases per 100,000 people per year and that of VTOS between 0.5 and 1 per 100,000 people per year, ATOS being sporadic. The ratio of those with decent suspicion for NTOS and VTOS, respectively, is about 80:20, whereas that of those undergoing surgical decompression is about 75:25. CONCLUSIONS: The rates of NTOS and VTOS, as aforementioned, are approximately 25 and 8 per year in a metropolitan area of 1,000,000, respectively. Although a rare disease, these numbers are not insignificant, although are much lower than prior estimates.

Numerical Correlation of Levator Advancement in Preoperative Planning.

BACKGROUND: Several procedures have been proposed for the treatment of eyelid ptosis, and both levator advancement and levator plication are widely used to shorten the levator palpebrae superioris. The purpose of this study was to quantify perioperative lid measurements in patients undergoing bilateral levator aponeurosis advancements to aid in preoperative planning. METHODS: Between July 2014 and June 2016, the authors performed a retrospective analysis of all bilateral upper eyelid levator advancement procedures for ptosis performed by the senior surgeon. There are a total of 21 patients (6 men and 15 women) with a mean age of 63 years (range, 48-79 years). The average time at follow-up was 5.3 months, with a range of 1 to 26 months. RESULTS: In this retrospective study, we collected data on presurgical measurements including marginal reflex distance 1 (MRD1), surgical technique used (symmetrical/asymmetrical levator advancement) with millimeters of advancement used, and postsurgical measurements. We found that on average, an advancement of 4 mm led to an improvement in MRD1 of 2.26 mm (n = 14), and advancement of 5 mm led to an improvement in MRD1 of 2.74 mm (n = 15). Patients also reported improvements in their quality of life. CONCLUSIONS: Our results may be used to guide clinicians in preoperative planning.