PubMed Health⌕ Search

Biomedical subjects

M Lanzetta

Publications and source records attributed to M Lanzetta.

At least 37 records · Page 2Linked to original sources
PubMed1996

Assessment of nerve ultrastructure by fibre-optic confocal microscopy.

Fibre-optic technology combined with confocality produces a microscope capable of optical thin sectioning. In this original study, tibial nerves have been stained in a rat model with a vital dye, 4-(4-diethylaminostyryl)-N-methylpyridinium iodide, and analysed by fibre-optic confocal microscopy to produce detailed images of nerve ultrastructure. Schwann cells, nodes of Ranvier and longitudinal myelinated sheaths enclosing axons were clearly visible. Single axons appeared as brightly staining longitudinal structures. This allowed easy tracing of multiple signal axons within the nerve tissue. An accurate measurement of internodal lengths was easily accomplished. This technique is comparable to current histological techniques, but does not require biopsy, thin sectioning or tissue fixing. This study offers a standard for further in vivo microscopy, including the possibility of monitoring the progression of nerve regeneration following microsurgical neurorraphy.

Animals↗
PubMed1996

Atraumatic tendon handling during tendon repair.

Two techniques are presented for atraumatic handling of tendon ends during repair of flexor and extensor tendons. If the tendon is cleanly transected, the suture is carried out by holding the tendon in nerve holding forceps. If debridement is needed, a slice is partly cut and used to handle the tendon; the slice is then cut off and discarded.

Humans↗
PubMed1996

Spontaneous thrombosis of palmar digital veins.

Five cases of spontaneous thrombosis of a palmar digital vein are presented. The patients, all female, complained of a tender and unsightly lump over the digital palmar surface at the proximal interphalangeal joint level. Two fingers were affected in one patient. None could recall any history of trauma. In four cases a surgical excision was carried out. Histology confirmed the intraoperative findings of thrombosis of a superficial digital vein in every case. All patients are free from recurrence at a mean follow-up of 2.5 years.

Adult↗
PubMed1996

Diagnostic ultrasound of the hand and wrist.

To assess the efficacy, role, and limitations of diagnostic ultrasound in the hand and wrist, the results of 98 examinations performed for a variety of surgical conditions were retrospectively analyzed. Ultrasound was shown to be reliable in evaluating radiolucent foreign body, tendon rupture versus tendon adhesion, tendinitis, peritendinitis, and ganglion cyst (specificity, 1; positive predictive value, 1). A correct suggestion of soft tissue mass histology was offered in six of eight operated cases. Tumor size and extent was accurately assessed in all but one case. The observed limitation of ultrasound was a small false negative rate in each category, which related to a variety of factors, including operator dependence, resolution threshold in the submillimeter range, image degradation due to postoperative edema, a narrow field of view, and one instance of indiscrete tumor margination. More work is needed to determine the role (if any) of ultrasound in the evaluation of peripheral nerve, triangular fibrocartilage, dorsal carpal ligament, and bone pathology.

Adolescent↗
PubMed1996

Scanning electron microscopy evaluation of endothelial regeneration in 1-mm PTFE prostheses.

This study documents the developmental stages of neoendothelium regeneration in 1-mm polytetrafluoroethylene (PTFE) prostheses. Scanning electron microscopy was used to follow the progression of platelet deposition, fibrin layering, and endothelial cell migration along the graft. The endothelial healing process was divided into six stages: platelet aggregation (stage I); fibrin network (stage II); bridging (stage III); progression (stage IVA); transmural migration (stage IVB); intimal closure (stage V); and endothelial thromboresistance (stage VI).

Animals↗
PubMed1996

Biomechanical explanation of a simultaneous closed rupture of both flexor tendons in the same digit.

Closed ruptures of both normal flexor tendons in the same finger are extremely rare, only nine cases having been reported in the literature. The authors describe the case of a patient who sustained a closed rupture of both flexor digitorum profundus and flexor digitorum superficialis of the ring finger, following a forced hyperextension injury. The present paper highlights the importance of the mechanism of injury and explains biomechanical basis. The patient was treated by a two-stage reconstruction of the flexor digitorum profundus and regained full flexion and extension of the finger.

Adult↗
PubMed1995

Neo-endothelialisation of PTFE microvascular grafts: a five-year experience.

This paper presents the results of a 5-year experience of the implantation of 1 mm diameter polytetrafluoroethylene (PTFE) prosthesis in rodents. By evaluating the implanted grafts at different intervals, the process of neo-endothelial healing can be divided into six phases: Platelet Aggregation Phase (Stage I); Fibrin Network Phase (Stage II); Bridging Phase (Stage III); Progression Phase (Stage IV-A); Transmural Migration Phase (Stage IV-B) (only in optimal grafts, with thin wall and long fibril length); Intimal Closure Phase (Stage V); and Endothelial Thromboresistance Phase (Stage VI). Grafts with 60 or 90 microns fibril length offer enough "anchoring space" for the ingrowth of neo-endothelium and they act as a framework for the neo-endothelial invasion. Furthermore, this type of material allows intramural migration and penetration of cellular elements. In particular, a network of capillaries traversing the graft wall and opening eventually on the luminal surface can provide multiple sources of neo-endothelium, contributing to the development of the inner neo-endothelial lining. Scanning electron microscopy can favourably assist in the evaluation of different types of PTFE grafts, with regard to their fibril length, diameter, and wall thickness.

Blood Vessel Prosthesis↗
PubMed1995

Clinical use of microvascular PTFE grafts.

This paper reports on the first clinical case where a polytetrafluoroethylene (PTFE) graft of less than 3 mm in diameter was implanted in the arterial system of a patient to bridge a vascular defect. A 1.5 cm long, 1.5 mm diameter prosthesis was interposed in the superficial palmar arch of a man who sustained a laceration of the palm of his dominant hand. The graft was implanted by means of the 3M Precise Microvascular Anastomotic System on one end, and by conventional microsurgical technique on the other end. There were no postoperative complications. The patient resumed his pre-injury activities 9 weeks after trauma. Serial Doppler ultrasound examinations showed normal blood flow and complete patency of the graft. An angiogram performed 12 weeks postoperatively confirmed the patency of the prosthesis. Twelve months post-operatively the patient is free from complications. The use of small diameter PTFE prostheses may be considered when planning grafting procedures for microvascular defects.

Adult↗
PubMed1995

A comparison of different surgical techniques in treating degenerative arthrosis of the carpometacarpal joint of the thumb. A retrospective study of 98 cases.

Between March 1977 and December 1991, 98 surgical procedures on 85 patients were performed at SOS Main Strasbourg for osteoarthrosis of the carpometacarpal joint of the thumb. The mean age was 56 and 90% were female; 13 were operated on bilaterally. 40% had Swanson arthroplasties (group 1), 15% Ashworth-Blatt hemiarthroplasties (group 2), and 45% had soft tissue arthroplasties (group 3). 62 cases were reviewed at an average follow-up of 5 years. Normal thumb range of motion was obtained in all cases, regardless of the technique used. Complete pain relief was achieved in 77% of the cases in group 1, 37.5% in group 2 and 71% in group 3. 15% of group 1 and 50% of group 2 required surgical revision, either for displacement or fracture of the implants. No revision was necessary in group 3. One case of silicone synovitis requiring secondary surgery was noted 6 years after surgery, accounting for 2.9% of the total number of silicone implants reviewed, but radiological signs of silicone synovitis were much more common (56%). Proximal metacarpal migration in group 3 averaged 38% of the initial arthroplasty space, and was not related to the type of ligamentoplasty used, or presence or absence of an "anchovy". The migration increased to 68% of the space if an associated MP joint arthrodesis was carried out at the same time. Complications included reflex sympathetic dystrophy (4% in group 1 and 14% in group 3). The Ashworth-Blatt hemiarthroplasty failed to gain satisfactory results, but both silicone arthroplasty and soft tissue arthroplasty proved to be useful procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Risk and complications in endoscopic carpal tunnel release.

Single portal endoscopic carpal tunnel release was carried out in 107 hands of 88 patients. There were 11 complications. These included incomplete release (2), post operative scarring around the median and ulnar nerves (2), laceration of the superficial palmar arterial arch (1), reflex sympathetic dystrophy (2), palmar fasciitis (1), and wound inflammation (3). In two cases there was no relief of symptoms. In one there was incorrect diagnosis and in another, incorrect indication for endoscopic carpal tunnel release. The follow-up was from 3 to 18 months with an average of 6.8 months. The overall results of the patients in this series are being presented in another paper. Of the 107 procedures, 73 were rated as having an excellent, 25 good, three fair, and six poor results. The case of laceration of the superficial palmar arterial arch is discussed in detail in the paper. The two cases of reflex sympathetic dystrophy and the one case of palmar fasciitis had mild clinical features and resolved within 3 months. The inflammation in three of the wounds at the wrist resolved within 2 days of removal of the percutaneous sutures. These three patients had returned to heavy hand activities within a few days of surgery.

Adult↗
PubMed1995

Versatility of the homodigital triangular neurovascular island flap in fingertip reconstruction.

This paper reports 25 cases of a versatile homodigital triangular neurovascular island flap for fingertip reconstruction. This flap was used to reconstruct traumatic oblique palmar amputations, with loss of fingertip pulp requiring advancement of not more than 2 cm. Good results were obtained in terms of fingertip contour and padding, sensibility, and functional recovery. The tendency for flexion contracture at the PIP joint was prevented by using a dynamic extension splint at night. Cold intolerance must be expected, especially in cold countries.

Adolescent↗
PubMed1995

Use of the 3M precise microvascular anastomotic system in hand surgery.

The results of a two-center clinical study on the use of the 3M Precise Microvascular Anastomotic System in microvascular procedures for hand trauma are presented. Since November 1992, 17 patients (age range, 18-76 years) have received an end-to-end vascular anastomosis using this device. All patients had vascular trauma or amputation requiring replantation or revascularization procedures. The diameter of the anastomosed vessels varied between 1 and 2 mm. Sixteen of the 17 anastomoses were at the level of or distal to the superficial arterial arch of the hand, with 5 anastomoses as distal as the distal interphalangeal joints. No early thromboses were observed in the postoperative period, and all operations were successful with regard to tissue survival and wound healing. Patency and quality of the blood flow at the site of repair were evaluated by means of Doppler ultrasound investigations. In a few cases, angiography was used to confirm patency of the device.

Adolescent↗
PubMed1995

Association of Wartenberg's syndrome and De Quervain's disease: a series of 26 cases.

We report on a series of 25 patients (26 cases) presenting an association of Wartenberg's radial neuritis and De Quervain's tenosynovitis. In all patients the diagnosis was made on clinical grounds. In group 1, conservative treatment of Wartenberg's syndrome was used in 16 patients (associated with surgical release of the first extensor compartment in 5 patients). Of the 14 patients available for follow-up at an average of 15 months, 9 (64 percent) were excellent and good results. In group 2 (11 patients, with 1 failure of conservative treatment), surgical treatment addressed both conditions. Neurolysis has to be performed at the classic proximal site of entrapment (constant excellent and good results), for the 2 cases of neurolysis at the styloid level gave fair results. It is particularly important to identify an associated Wartenberg's syndrome before performing a release of the first dorsal compartment to avoid incomplete relief or even aggravation of neuritis, exposing the surgeon to litigation.

Adult↗
PubMed1994

Idiopathic avascular necrosis of the scaphoid.

Idiopathic avascular necrosis of the scaphoid is a rare condition. A review of the literature shows a variety of conditions labelled as spontaneous avascular necrosis or Preiser's disease. In this paper we report on a study of eight patients with idiopathic avascular necrosis affecting only the proximal pole of the scaphoid. Seven of these patients had positive ulnar variance. The possible aetiology is discussed and the natural history has been studied. A staging system is proposed, as this helps to determine the prognosis and appropriate management. Two of our patients were managed conservatively; the others were treated successfully by partial silastic replacement of the scaphoid.

Adult↗