Microanatomy of Milk Ducts in the Nipple

ArticleinEuropean Surgical Research 38(6):545-9 · February 2006with20 Reads
DOI: 10.1159/000096775 · Source: PubMed
The aim of this study was to determine number and diameter of milk ducts in the nipple and to investigate the possible influences of age, breast weight, and diameter of the nipple on the number of ducts. Two hundred and twenty-six carcinoma mastectomy specimens were weighed and the nipple diameters measured. The number of ducts was counted in histological cross sections. Mean diameter of the nipple and mean breast weight were 13.9 mm and 844.6 g, respectively. There was a small but statistically significant positive correlation between nipple diameter and number of milk ducts (rho = 0.158; p = 0.01), but no correlation with breast weight. The mean number of ducts in the nipple duct bundle was 17.5. This is significantly higher than the number of ducts reported to open on the nipple surface. This discrepancy could reflect duct branching within the nipple or the presence of some ducts which do not reach the nipple surface. Smaller breast ducts (diameter < 0.5 mm) represent nearly 50% of the nipple ducts and could be a challenge to the ductoscopy technology.
    • "They, however , did not state how many of the imaged ducts ran to the nipple surface and exhibited an orifice [5]. There is a consensus in the literature to the effect that the number of milk ducts inside the lactating breast identified by ultrasound imaging or histologic sectioning is higher than the number of orifices on the nipple surfaces [7,13141516. There is hardly any published in vivo study that addresses the number of milk duct orifices under functional aspects and analyzes their association with variables in the infant and the mother. "
    [Show abstract] [Hide abstract] ABSTRACT: In vitro and in vivo analyses differ between the number of milk ducts found in the lactating breast, and there is a lack of knowledge as to whether or not external factors in the mother or the child affect the number of ductal orifices. The aim of this study was to determine the number of milk duct orifices in vivo and to investigate the possible influence of variable parameters in mother and infant. Study design: Prospective clinical trial. In 98 breastfeeding women we investigated the nipple surface in order to identify the number of milk duct orifices using Marmet's manual milk expression technique. In addition mothers were interviewed on different parameters of birth and breastfeeding. Every nipple had 3.90 +/- 1.48 milk duct orifices on average. There was no significant difference between left and right breasts. The use of a breast pump in addition to breastfeeding did not have any effect on the number of ductal orifices.Multiparous women exhibited more ductal orifices (8.5 +/- 3.0) as compared to primipara (7.1 +/- 2.7). Boys were associated with significantly more ductal orifices in their mother's right breast (4.2 +/- 1.7) than girls (3.5 +/- 1.4). Furthermore boys were breastfed for longer per session. A shorter birth height of males correlated with more ductal orifices in left nipples. Fluid intake of mothers was associated with a higher number of ductal orifices. Restless infant behavior could not be explained by less milk duct orifices. Pain in the breast during breastfeeding did not have an influence on ductal orifices either. Psychological criteria, such as duration of maternity leave and total intended breastfeeding period, did not affect the number of orifices in the papilla mammaria of breasts during lactation. For the first time an in vivo investigation of the number of ductal orifices in lactating women was conducted non-invasively and associations with variables in the mother and the child, birth parameters in infants, and breastfeeding parameters in mothers and children were assessed. We conclude that the number of activated ductal orifices on the surface of the nipple is primarily associated with functional aspects.
    Full-text · Article · Apr 2014
    • "The nipple ducts are crenulated and approximately 0.5 mm in diameter (Taneri et al., 2006; Rusby et al., 2007), with horizontally orientated muscles located distally and which provide a sphincter-like function (Tezer et al., 2011). A median of 23–27 ducts at the base of the nipple has been consistently documented in histological sections of mastectomy specimens (Going and Moffat, 2004; Taneri et al., 2006; Rusby et al., 2007). These results are in conflict with other methods of investigation such that some ducts can be cannulated, but do not appear to enter the breast, and much fewer ducts (five to nine) appear to yield milk (Love and Barsky, 2004). "
    [Show abstract] [Hide abstract] ABSTRACT: Mammary glands are unique to mammals, with the specific function of synthesizing, secreting, and delivering milk to the newborn. Given this function, it is only during a pregnancy/lactation cycle that the gland reaches a mature developmental state via hormonal influences at the cellular level that effect drastic modifications in the micro- and macro-anatomy of the gland, resulting in remodeling of the gland into a milk-secretory organ. Pubertal and post-pubertal development of the breast in females aids in preparing it to assume a functional state during pregnancy and lactation. Remarkably, this organ has the capacity to regress to a resting state upon cessation of lactation, and then undergo the same cycle of expansion and regression again in subsequent pregnancies during reproductive life. This plasticity suggests tight hormonal regulation, which is paramount for the normal function of the gland. This review presents the current status of knowledge of the normal macro- and micro-anatomy of the human mammary gland and the distinct changes it undergoes during the key developmental stages that characterize it, from embryonic life through to post-menopausal age. In addition, it discusses recent advances in our understanding of the normal function of the breast during lactation, with special reference to breastmilk, its composition, and how it can be utilized as a tool to advance knowledge on normal and aberrant breast development and function. Finally, anatomical and molecular traits associated with aberrant expansion of the breast are discussed to set the basis for future comparisons that may illuminate the origin of breast cancer. Clin. Anat. Clin. Anat. 2012. © 2012 Wiley Periodicals, Inc.
    Article · Jan 2013
  • [Show abstract] [Hide abstract] ABSTRACT: Presents results on using a statistical model motivated by the wavelet transform to represent non-stationary signals typically encountered in machinery monitoring applications. The authors propose the use of a frame-based system in which the data in each frame is modeled as a multiscale stochastic process. The parameters of a multiscale model are used as features for each frame, where each frame of features is modeled as a sample of a multivariate, multimodal distribution. Classification of machine states based on monitoring signals is performed by comparing likelihood scores for each machine state. The authors present an example of applying the system to data consisting of a superposition of damped sinusoids, as a way of illustrating system performance for the case of transient monitoring signals. They compare their system to one which is trained using a DFT-based (non-time-frequency-based) representation (in particular, LPC coefficients) and show that their system exhibits both superior performance as well as greater robustness to noise in the signals. They also compare results using multiscale parameters versus LPC coefficients for the case of synthesized autoregressive signals and for the case of actual, measured signals from a weld depth monitoring system
    Conference Paper · Nov 1994 · Clinical Anatomy
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