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Vincent Casoli

Publications and source records attributed to Vincent Casoli.

8 recordsLinked to original sources

Arterial blood supply of the extensor apparatus of the long fingers.

BACKGROUND: The extensor apparatus vascularization is less studied compared with flexor tendons. The aim of the present anatomical work was to study it in a more systematic way and find clinical applications. METHODS: The study was carried on 40 fingers from 10 fresh cadaver hands. Two catheters (16 gauge) were introduced into the radial and ulnar arteries on the volar side of the wrist. Acetone was used for arterial cleaning and color latex for the arterial system coloration. The authors proceeded with the dissections, always in the same manner: they first made the longitudinal dorsal incisions from the metacarpophalangeal to distal interphalangeal joints. Raising the skin, they identified the thin subcutaneous branches into the hypodermal plane; they followed their course until their origin, which allowed identification of the arterial branches of the extensor apparatus. For measurements, they used as a point of reference the emergence distance of those dorsal branches from the metacarpophalangeal and proximal and distal interphalangeal joints. RESULTS: The extensor apparatus vascularization was segmental, realized through the paratenon from the branches of a vascular cutano-tendino-osseous complex through a common trunk, issued from the propria digital artery. This complex nourished not only the extensor apparatus but also the dorsal digital skin and periosteum. Its location was consistent at the level of both proximal and middle phalanges. CONCLUSIONS: This consistency explains the anatomical basis for the realization of composite-free tissue transfer in cases of banked fingers. The osteotomies could be performed at well-defined distances from the joints.

Aged↗

In vivo and in vitro evidence of dermal fibroblasts influence on human epidermal pigmentation.

Using chimeric human epidermal reconstructs, we previously demonstrated that epidermal pigmentation is dependent upon the phototype of melanocytes. We report here several lines of experimental evidence for dermal modulation of human epidermal pigmentation. First, phototype II-III epidermal reconstructs grafted on the back of immunotolerant Swiss nu/nu mice developed a patchy pigmentation dependent on the presence of colonizing human or mouse fibroblasts. Similarly, human white Caucasoid split-thickness skin xenografted on the same mouse strain became black within 3 months and histochemistry revealed a phototype VI pattern of melanin distribution. In vitro, human fibroblasts colonizing human dead de-epidermized dermis (DDD) induced a decrease in epidermal pigmentation whereas mouse (Swiss nu/nu) fibroblasts increased epidermal pigmentation. Conditioned medium from mice (Swiss nu/nu) fibroblasts also increased pigmentation whereas conditioned medium from human fibroblasts had no significant effect. Lastly, epidermal reconstructs made with normal or vitiligo keratinocytes and/or normal or vitiligo melanocytes from the same donor grown on DDD originating from several donors of the same clinical phototype did not pigment similarly and no specific dermal influence was noted for vitiligo. Thus, fibroblast secretion and acellular dermal connective tissue itself significantly influence melanocyte proliferation and melanin distribution/degradation. Our study suggests that murine fibroblasts are more potent than human fibroblasts in secreting soluble factors which can act directly on pigmentation, such as SCF, or activate keratinocytes to produce basement membrane proteins or melanogenic factors.

Animals↗

Anatomy and blood supply of the subgaleal fascia flap.

The subgaleal fascia (SGF) is a distinct layer in the temporal fossa situated between the superficial fascia and galea aponeurotica and the temporal fascia covering the superficial surface of the temporal muscle. The SGF is used most frequently for otologic reconstruction. Reviewing the literature, however, showed many contradictory findings about dissection of an independent SGF layer, its blood supply, and the possibility of harvesting it as part of a combined flap. Our study, carried out on ten fresh cadavers, presents a detailed view of the blood supply of the SGF to develop a safe method of harvesting an inferior-based SGF. Our systematic plane-by-plane approach, associated with a transparent grid applied on each dissection, allowed us to quantify the branches from each plane and to localize precisely their entering sites from a reference "zygomatic point." The SGF had no ascending axial vascular supply entering from its base; according to our results, therefore, the SGF could not be harvested alone as an inferior pedicled flap down to the zygomatic arch. It may be feasible, however, to harvest a SGF flap when a strip of the superficial fascia is associated with its middle third. Therefore, we suggest that an average height of 5.4 cm of superficial fascia should be included in an inferior-based pedicle of a SGF.

Aged↗

Comparison of long-term survival of pigmented epidermal reconstructs cultured in vitro vs. xenografted on nude mice.

Epidermal reconstructs incorporating pigment cells have been used in vitro over the last decade to study the physiology of the epidermal melanin unit. However, the major limitation of this technology is the duration of the assays, which need to be completed within 2-3 weeks to obviate the problem of epidermal senescence and excessive terminal differentiation. This becomes a major problem for studying long-term biological phenomena in photoprotection and epidermal skin cancers. We report here a simplified surgical technique in immunotolerant mice allowing long-term studies. The creation of a vascularized mouse skin flap is the key point of the surgical procedure. Long-term pigmentation of the xenografts seemed macroscopically successful, but surprisingly microscopy at 11 and 16 weeks postgrafting showed mostly dermal pigment aggregates and rare Melan-A positive dermal and epidermal pigment cells. In the same reconstructs maintained in vitro, dermal pigment and dermal pigment cells were never noted. It could be speculated that in our model, the colonization of the xenografted dead human dermis by murine cells influences melanocyte survival.

Animals↗

Angiosomes of the brachial plexus: an anatomical study.

This anatomical study analyzed the neurovascular relationships of the brachial plexus. Ten fresh cadaveric brachial plexuses were examined after injection of the arterial system. The vascular anatomical features of the brachial plexus were documented with microdissection after lead oxide/gelatin injection. The specimens were analyzed by using radiography (including digital subtraction techniques) and light-microscopic, macroscopic, and digital photography. Four angiosomes, based on the subclavian, axillary, vertebral, and dorsal scapular arteries, were observed. As noted in previous angiosome studies, connections between angiosome territories lay within tissues, in this case, nerve trunks. Nutrient vessels penetrated nerve trunks at points of branching within the brachial plexus, with a Y-shaped mode of division on entry. The vascular supply was markedly rich, often with true anastomotic connections occurring within the nerves. There was much variation in supply, depending on the vascular anatomical features of the subclavian artery.

Aged↗

Reconstruction of short lower leg stumps with the osteomusculocutaneous latissimus dorsi-rib flap.

To avoid a more proximal amputation at the distal part of the thigh, and when the knee joint is preserved, it is possible to lengthen short lower leg stumps. The authors report five cases in which the latissimus dorsi-rib flap was used to achieve a satisfactory functional prosthetic result. The bone segment is long enough to both lengthen the stump and allow its extremities to be firmly fixed to the tibia. Depending on the remaining tibia length, one or two ribs were included in the flap. The procedure allowed achievement of a 5-cm to 9-cm lengthening of the tibia. Bone healing time was 5 to 6 months and allowed prosthetic rehabilitation and ambulating 5 to 7 months after surgery. Final range of motion of the knee joint is compatible with normal ambulating, and the prosthesis is well tolerated. This procedure, which provides a large amount of skin, muscle, and bone, is very effective for reconstruction of short lower leg stumps.

Adult↗