Autologous fat graft in nipple reconstruction

Reconstruction of the nipple is the penultimate step in breast reconstruction after mastectomy. A number of reconstructive techniques have been described for nipple reconstruction including skin grafts, composite grafts, and various local flaps. The authors' preferred reconstructive technique is the local C-V or modified star flap. This flap produces an excellent reconstruction, but it is dependent on underlying subcutaneous fat to provide bulk to the reconstructed nipple. In most instances, the subcutaneous tissue is adequate. However, under certain circumstances, the subcutaneous fat may be insufficient to produce a nipple of adequate projection. Two cases of bilateral nipple reconstruction after soft-tissue expansion and implant placement and subsequent nipple reconstruction with local flaps provided inadequate nipple projection. These instances, as well as a retrospective review of reconstructed nipples after mound restoration using a variety of techniques, led the authors to conclude that a more predictable alternative to sustain nipple projection was necessary. The authors identified two broad categories of breast reconstruction patients in whom this new technique would be beneficial. In the first category of patients, breast mounds are reconstructed with tissue expansion and implant insertion, and in the second category, breast mounds are reconstructed by any technique in which the nipple reconstruction subsequently flattens. This article describes the indications, techniques, and experience in 13 patients treated over a 10-month period with fat grafting for nipple reconstruction.     

Microtia reconstruction: does the cartilage framework grow?

The use of free rib cartilage ear frameworks in unilateral microtia reconstruction has prompted much discussion about their potential for growth. The senior author has reconstructed ear frameworks in 132 microtia patients, most of whom were under 3 years of age when surgery was initiated. Of this group, 29 were assessed for ear growth through comparison of the lead-plate model of the original normal ear to the normal ear growth and the reconstructed ear framework after a period of at least 2 years. Similarly, 14 reconstructed ears were compared to 14 normal ears at least 2 years after reconstruction. The perimeters of tracings made from the original lead plates and of tracings of normal and reconstructed ears were determined by image analysis techniques. The results demonstrated no significant difference in growth between normal ears and reconstructed ear frameworks after an interval of at least 2.5 years. Therefore, the reconstructed ear is growing at a rate similar to that of the normal ear.     

Perforator-preserving chondrocutaneous rotation flap reconstruction of auricular defects

A technique of chondrocutaneous flap reconstruction of the ear that preserves the perforating branches of the posterior auricular artery is described. Preservation of the perforators offers improved safety in high-risk patients because it maintains the blood supply to the anterior surface of the ear. This perforator-preserving technique also emphasizes simplicity of flap design, concealment of scars, and preservation of ear shape. It is best suited for reconstructing defects of the scapha, antihelix, or triangular fossa up to approximately 2 cm in diameter. A variety of chondrocutaneous rotation flaps have been developed for reconstructing helical and nonhelical defects. These flaps have been designed on the basis of the size and location of the surgical defect. Although previously described techniques are usually reliable, extensive dissection and mobilization can injure perforators, leading to vascular compromise. When flap reconstruction is used in high-risk patients, it is necessary to protect the blood supply, and perforator-preserving flap reconstruction offers improved safety. The perforator-preserving technique was used in six consecutive high-risk patients during a 2-year period. Good results were obtained in all cases, including in patients who smoked cigarettes or had extensive medical problems.     

Soft-tissue injuries of the fingertip: methods of evaluation and treatment. An algorithmic approach

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the anatomy of the fingertip. 2. Describe the methods of evaluating fingertip injuries. 3. Discuss reconstructive options for various tip injuries. SUMMARY: The fingertip is the most commonly injured part of the hand, and therefore fingertip injuries are among the most frequent injuries that plastic surgeons are asked to treat. Although microsurgical techniques have enabled replantation of even very distal tip amputations, it is relatively uncommon that a distal tip injury will be appropriate for replantation. In the event that replantation is not pursued, options for distal tip soft-tissue reconstruction must be considered. This review presents a straightforward method for evaluating fingertip injuries and provides an algorithm for fingertip reconstruction.     

A practical guide for assigning sex and stage of maturity in sturgeons and paddlefish

The goal of this paper is to improve the assignment of sex and stage of maturity for sturgeons and paddlefish by providing both an overview of the gonadal stages of maturity and general guidelines and training needs for the four most commonly used techniques to assign sex and stage of maturity including ultrasound, endoscopy, plasma sex steroid analysis, and biopsy of the gonads via celiotomy. Sturgeons and paddlefish do not express external sexual dimorphism, which can make assignment of sex and stage of maturity challenging. Correct assignment of sex and stage of maturity is important for management of wild populations as well as for aquaculture, whether for conservation or commercial production. Selecting a technique to use when assigning sex and stage of maturity will depend on a number of factors; a comparison among these techniques is provided in this review, including tradeoffs, to help assist in technique selection based on specific research or production goals. The use of more than one technique may be beneficial to determine error rates associated with a single technique. This review is intended to serve as a practical resource when assigning sex and stage of maturity in field or laboratory settings in addition to stressing the importance of correctly identifying sex during research and in the management of populations.     

Bipedicle strap flaps in reconstruction of longitudinal dorsal skin defects of the digits

Dorsal skin defects in which the loss of integument is longitudinal in shape are not uncommon after injury by rotating machinery and by glass shearing along the length of the digit. This shape of defect is difficult to reconstruct with commonly used flaps but lends itself to reconstruction by the use of longitudinal bipedicle strap flaps moved across the dorsum of the finger from lateral to medial. A variant of this traditional technique was used in the reconstruction of 28 dorsal digital defects. The incidence of these defects and the need for this reconstructive technique were analyzed by a review of 1077 patients with dorsal digital injuries treated in a 6-year period between 1989 and 1995. Approximately 20 percent of all dorsal digital injuries requiring flap reconstruction were suitable for reconstruction with bipedicle strap flaps.     

Modified Antia-Buch repair for full-thickness upper pole auricular defects

Various reconstructive techniques have been described for repair of full-thickness upper pole auricular defects. The wedge excision commonly used for treatment of upper pole tumors allows excision and reconstruction in a single stage. However, this technique suffers from major deficiencies. We apply the concept of crescentic scaphal excision and the Antia-Buch advancement-rotation flap principle to repair various full-thickness upper pole auricular defects resulting from excision of skin lesions in eight consecutive patients. The technique achieves a natural auricular shape in three dimensions with minimal disruption of the anatomic landmarks and avoids conspicuous scars. It has several advantages over the original Antia-Buch repair and other techniques used for reconstruction of full-thickness upper pole auricular defects.     

先天性小耳畸形手术治疗的研究进展

先天性小耳畸形是发病率较高的头面部畸形之一,常为耳廓及中耳腔同时存在,内耳发育不良相对少见,这一疾病所致的缺陷不仅影响到患者的容貌,更重要的是导致患者听觉功能的障碍,严重影响到患者的日常工作学习和生活。部分患者还伴有或多或少的心理影响,这在双侧小耳畸形的患者中更多见。手术是其主要的治疗方法,要求不仅重建外形正常的耳廓,同时还拥有正常或接近正常的听力。外耳廓再造和听力重建手术不仅使先天性小耳畸形患者的耳部外观明显改善,还能使其听觉功能进一步提高。本文主要综述了先天性小耳畸形的病因和流行病学、分类、手术时机和方式的选择、听力重建、耳廓再造的方法及组织工程学耳再造技术,重点介绍了耳廓再造材料的选择及手术注意点,以期为先天性小耳畸形的临床治疗提供更多理论依据。     

Seeing beyond the limit: A guide to choosing the right super-resolution microscopy technique

Super-resolution microscopy has become an increasingly popular and robust tool across the life sciences to study minute cellular structures and processes. However, with the increasing number of available super-resolution techniques has come an increased complexity and burden of choice in planning imaging experiments. Choosing the right super-resolution technique to answer a given biological question is vital for understanding and interpreting biological relevance. This is an often-neglected and complex task that should take into account well-defined criteria (e.g., sample type, structure size, imaging requirements). Trade-offs in different imaging capabilities are inevitable; thus, many researchers still find it challenging to select the most suitable technique that will best answer their biological question. This review aims to provide an overview and clarify the concepts underlying the most commonly available super-resolution techniques as well as guide researchers through all aspects that should be considered before opting for a given technique.     

Primary nonmicrosurgical reconstruction following ear avulsion using the temporoparietal fascial island flap

Primary ear reconstruction following avulsion using a temporoparietal fascial island flap based on the superficial temporal vessels is presented as a modification of an existing technique for the acute treatment of this difficult problem, offering a further alternative to established traditional nonmicrosurgical procedures.     

Conchal transposition flap for postburn ear deformities

Severe thermal injuries to the external ear often lead to extensive loss of peripheral structures such as helix and lobule but frequently spare the more central parts of the ear, even though they may be grossly deformed by scar contracture. The use of spared conchal structures as a transposition flap in combination with remodeling of the residual auricle and release of surrounding scar when indicated has been a useful technique in the reconstruction of a frequently occurring type of postburn ear deformity. Twenty-four ears have been reconstructed in 18 patients over the past 5 years using a conchal transposition flap. The residual concha with its overlying skin can be transposed superiorly, based on a very narrow pedicle in the area of the crus helicis. The raw central area remaining is then resurfaced with a split-thickness skin graft. This technique maximally utilizes the unique remaining auricular elements and can provide a satisfactory reconstruction in selected patients without resorting to more complex and extensive procedures. There have been no significant complications in this series, and patient acceptance of the results has been excellent.     

Conformational heterogeneity and probability distributions from single-particle cryo-electron microscopy

Single-particle cryo-electron microscopy (cryo-EM) is a technique that takes projection images of biomolecules frozen at cryogenic temperatures. A major advantage of this technique is its ability to image single biomolecules in heterogeneous conformations. While this poses a challenge for data analysis, recent algorithmic advances have enabled the recovery of heterogeneous conformations from the noisy imaging data. Here, we review methods for the reconstruction and heterogeneity analysis of cryo-EM images, ranging from linear-transformation-based methods to nonlinear deep generative models. We overview the dimensionality-reduction techniques used in heterogeneous 3D reconstruction methods and specify what information each method can infer from the data. Then, we review the methods that use cryo-EM images to estimate probability distributions over conformations in reduced subspaces or predefined by atomistic simulations. We conclude with the ongoing challenges for the cryo-EM community.     

Recent developments in technics of nuclear magnetic resonance imaging

Three main aspects of presently developed nuclear magnetic resonance imaging techniques are pointed out in this short review: first, the importance of Fourier transform as reconstruction technique is recalled; secondly, the problem of the choice of the magnetic field value is raised and third, new trends in magnetic imaging are noticed such as the use of nuclei other than hydrogen or the improvement of phase contrast methods.     

Surgical treatment of osteoarthritis of the carpometacarpal joint of the thumb: a systematic review

In most cases of basal joint osteoarthritis, surgery becomes an option at stages II, III, and IV, as classified by Eaton. Controversy exists regarding which technique achieves the best outcome. This systematic review was undertaken to address the question of which technique, if any, offers the best outcome to patients with osteoarthritis of the first carpometacarpal joint greater than stage II. A thorough search of the electronic databases Cochrane, Cinahl, Healthstar, and MEDLINE/PubMed was undertaken to identify reviews and articles on primary comparative studies of the different surgical options. The methodological quality of the retrieved articles was assessed on the basis of specific criteria. Inclusion criteria were applied to 44 of 254 possibly relevant articles. Eight reviews and 18 comparative studies met the criteria and were reviewed. Each of the techniques, arthrodesis, trapeziectomy with or without biological/synthetic interposition, osteotomy, and joint replacement, was associated with unique benefits and risks. There was great variability in outcome measurements. The majority of retrieved review articles claim that ligamentous reconstruction and tendon interposition may represent the best option; however, validity assessment of these studies revealed methodological flaws. Furthermore, results from the articles on comparative studies indicate that ligamentous reconstruction and tendon interposition may provide no additional benefit when compared with arthrodesis and trapeziectomy alone or with tendon interposition. There is no consensus as to which clinical outcomes are most important in thumb basal joint surgery and how these should be measured. This renders the appraisal and comparison of such studies a challenging task. Until large randomized controlled trials that compare techniques in similar populations with respect to staging and prognostic factors are undertaken and the clinical outcomes are clearly defined, surgeons will continue to claim superiority of one technique over another without supporting evidence.     

Segmentation algorithms for ear image data towards biomechanical studies

In recent years, the segmentation, i.e. the identification, of ear structures in video-otoscopy, computerised tomography (CT) and magnetic resonance (MR) image data, has gained significant importance in the medical imaging area, particularly those in CT and MR imaging. Segmentation is the fundamental step of any automated technique for supporting the medical diagnosis and, in particular, in biomechanics studies, for building realistic geometric models of ear structures. In this paper, a review of the algorithms used in ear segmentation is presented. The review includes an introduction to the usually biomechanical modelling approaches and also to the common imaging modalities. Afterwards, several segmentation algorithms for ear image data are described, and their specificities and difficulties as well as their advantages and disadvantages are identified and analysed using experimental examples. Finally, the conclusions are presented as well as a discussion about possible trends for future research concerning the ear segmentation.     

Principles,techniques, and applications of biocatalyst immobilization for industrial application

Immobilization is one of the most effective and powerful tools used in industry, which has been studied and improved since the last century. Various immobilization techniques and support materials have been used on both laboratory and industrial scale. Each immobilization technique is applicable for a specific production mostly depending on the cost and sensibility of process. Compared to free biocatalyst systems, immobilization techniques often offer better stability, increased activity and selectivity, higher resistance, improved separation and purification, reuse of enzymes, and consequently more efficient process. Recently, many reviews have been published about immobilization systems; however, most of them have focused on a specific application or not emphasized in details. This review focuses on most commonly used techniques in industry with many recent applications including using bioreactor systems for industrial production. It is also aimed to emphasize the advantages and disadvantages of the immobilization techniques and how these systems improve process productivity compared to non-immobilized systems.     

Evaluation of nodal patterns for melanoma of the ear

Treatment of malignant melanoma of the external ear presents unique challenges. Because of the significant debate regarding the efficacy and validity of using sentinel lymph node mapping for the treatment of ear melanomas, data for a population of patients with melanomas of the ear who underwent surgical excision and reconstruction were reviewed to determine the efficacy of sentinel node mapping. A retrospective chart review of cases treated by a single surgical oncologist was performed. All patients who were treated for malignant melanomas and required reconstruction of the external ear by the plastic surgical service between 1995 and 2001 were identified. Nineteen patients were selected, of whom nine underwent sentinel node mapping. The average age of the patients was 65.2 years. Evaluation of melanoma depth, medical history, surgical margins, lymph node metastasis, and recurrence was performed. Lymphoscintigraphy with technetium-99-sulfur colloid and 1% Lymphazurin (isosulfan blue; Zenith Parenterals, Rosemont, Ill.) demonstrated widely variable lymphatic drainage patterns. The lower tail of the parotid gland and the upper cervical area were the two most common locations. The average number of sentinel nodes identified and removed was 3.7. The average Breslow thickness for these patients was 2.3 mm. None of these patients demonstrated micrometastatic disease in their sentinel nodes. The most common reconstructive procedure after surgical resection was the use of rotational advancement flaps. Localization of radioactivity, as detected with external technetium-99 scanning, was the most reliable method for detection of the sentinel lymph node basins and the individual nodes. The average value for the primary injection site was 8375 counts per second, and the average value for the nodes removed was 973.5 counts per second. Of the nine patients who underwent sentinel lymph node mapping, only one, with an initial lesion depth of 5 mm, developed a local recurrence. The average follow-up period in this study was 21 months (range, 12 to 79 months). All patients in this study were evaluated at least 1 year after the initial surgical resection. Patients were monitored by the same surgical oncologist every 3 months for the first 2 years. Little can be found in the literature regarding the efficacy of sentinel node biopsies for ear melanomas. Larger studies are indicated; however, it seems that this method is practical for designing therapeutic methods for patients with melanoma of the ear.     

A new technique for skin grafting in avascular areas: a preliminary report.

A 3 X 3 cm, buried, split-skin graft will survive on an avascular bed if it is temporarily covered with a skin flap. Four cases of secondary ear reconstruction are presented, in which this technique was effectively used.