The utility of parathyroid autofluorescence as an adjunct in thyroid and parathyroid surgery 2023.

Thyroid and parathyroid surgery requires careful dissection around the vascular pedicle of the parathyroid glands to avoid excessive manipulation of the tissues. If the blood supply to the parathyroid glands is disrupted, or the glands are inadvertently removed, temporary and/or permanent hypocalcemia can occur, requiring post-operative exogenous calcium and vitamin D analogues to maintain stable levels. This can have a significant impact on the quality of life of patients, particularly if it results in permanent hypocalcemia. For over a decade, parathyroid tissue has been noted to have unique intrinsic properties known as "fluorophores," which fluoresce when excited by an external light source. As a result, parathyroid autofluorescence has emerged as an intra-operative technique to help with identification of parathyroid glands and to supplement direct visualization during thyroidectomy and parathyroidectomy. Due to the growing body of literature surrounding Near Infrared Autofluorescence (NIRAF), we sought to review the value of using autofluorescence technology for parathyroid detection during thyroid and parathyroid surgery. A literature review of parathyroid autofluorescence was performed using PubMED. Based on the reviewed literature and expert surgeons' opinions who have used this technology, recommendations were made. We discuss the current available technologies (image vs. probe approach) as well as their limitations. We also capture the opinions and recommendations of international high-volume endocrine surgeons and whether this technology is of value as an intraoperative adjunct. The utility and value of this technology seems promising and needs to be further defined in different scenarios involving surgeon experience and different patient populations and conditions.

Measuring caloric response: comparison of different analysis techniques.

INTRODUCTION: Electronystagmography (ENG) testing has been supplanted by newer techniques of measuring eye movement with infrared cameras (VNG). Most techniques of quantifying caloric induced nystagmus measure the slow phase velocity in some manner. Although our analysis is carried out by very experienced assessors, some systems have computer algorithms that have been "taught" to locate and quantify maximum responses. We wondered what differences in measurement might show up when measuring calorics using different techniques and systems, the relevance of this being that if there was a change in slow phase velocity between ENG and VNG testing when measuring caloric response, then normative data would have to be changed. There are also some subjective but important aspects of ENG interpretation which comment on the nature of the response (e.g. responses which might be "sporadic" or "scant"). METHODS: Our experiment compared caloric responses in 100 patients analyzed four different ways. Each caloric was analyzed by our old ENG system, our new VNG system, an inexperienced assessor and the computer algorithm, and data was compared. CONCLUSIONS: All four systems made similar measurements but our inexperienced assessor failed to recognize responses as sporadic or scant, and we feel this is a limitation to be kept in mind in the rural setting, as it is an important aspect of assessment in complex patients. Assessment of complex VNGs should be left to an experienced assessor.

Neurodevelopment of adopted children exposed in utero to cocaine: the Toronto Adoption Study.

BACKGROUND: Published studies of children's neurodevelopment after in utero exposure to cocaine have not separated intrauterine from postnatal environmental effects as cocaine-using mothers cluster in low socioeconomic classes and have other risk factors. METHODS: To overcome this limitation, a study was done to assess physical and neurodevelopmental characteristics of 52 children: 26 were adopted by parents who sought counselling in the Motherisk Program at the University of Toronto for prenatal cocaine exposure, and 26 were controls matched for maternal intelligence quotient (IQ), socioeconomic status and gestational age. MAIN OUTCOME MEASURES: Head circumference, McCarthy General Cognitive Index (GCI) score, language performance and temperament tests. RESULTS: The children in the study group had smaller head circumferences (34th versus 54th percentiles p = 0.009), lower McCarthy GCI scores (102.8 versus 114.2, p = 0.02), poorer receptive and expressive language performance on the Reynell test, and higher activity levels, less persistence and increased distractibility on temperament tests. On multivariate analysis, cocaine exposure was significantly (p = 0.001) associated with lower IQ and poorer language development independent of intrauterine growth retardation and other potential confounders. INTERPRETATION: By controlling for postnatal environmental factors, this adoption study documents intrauterine developmental risks associated with cocaine exposure. Follow-up into school years is warranted to evaluate the extent of these effects.