Cancellation of image crosstalk in time-sequential displays of stereoscopic video.

Stereoscopic visualization systems based on liquid crystal shutter (LCS) eyewear and cathode-ray tube (CRT) displays provide today the best overall quality of three-dimensional (3-D) images and therefore have a dominant position in commercial as well as professional markets. Due to the CRT and LCS characteristics, however, such systems suffer from perceptual crosstalk ("shadows") at object boundaries that can reduce, and at times inhibit, the ability to perceive depth. In this paper, we propose a method to reduce such crosstalk. We present a simple model for intensity leak, we assess model parameters for a time-sequential LCS/CRT system and we propose a computationally efficient algorithm to eliminate the crosstalk. Since the full crosstalk elimination implies an unacceptable image degradation (reduction of contrast), we study the tradeoff between crosstalk elimination and image contrast. We describe experiments on synthetic and natural stereoscopic images and we discuss informal subjective viewing of processed images. Overall, the viewer response has been very positive; 3-D perception of many objects became either much easier or even effortless. Since the proposed algorithm can be easily implemented in real time (only linear scaling and table look-up are needed), we believe that it can be successfully used today in various stereoscopic applications suffering from image crosstalk. This is particularly true for PC-based 3-D viewing where the algorithm can be executed by the CPU or by an advanced graphics board.

Trauma of the fatty tissue.

Contusions of soft tissues are frequently encountered but the more often without any major consequence. However, trauma of the fat may induce complications ranging from mere lymphatic effusion to the apparition of pseudo lipoma or even, exceptionally, of fat embolism. Although rare, one must be aware of these complications as they appear sometimes long after the trauma.

Early dermabrasion of deep dermal burns with sandpaper. Case reports.

Deep dermal burns are initially difficult to evaluate, and they sometimes heal spontaneously. We present our experience of dermabrasion with sandpaper in four patients. It is a useful alternative to early excision of the scar. Skin grafts are not always required and the aesthetic results are excellent. Dermabrasion should be considered routinely for all deep dermal burns and particularly for facial burns and those caused by scalds.

[Launois-Bensaude disease. Apropos of 2 new cases]. / Maladie de Launois-Bensaude. A propos de deux nouveaux cas.

Data relating to Launois-Bensaude disease are reviewed and two cases reported. Both patients were dyspneic, one of them presenting preoperative trachea deviation, a complication reported in only about 2% of cases documented in the literature. Dissection of these non-encapsulated fatty tumors is difficult and can lead to complications, but surgical excision remains the only possible treatment.

[Cutaneous burns caused by Yperite. Apropos of 2 new cases]. / Brûlures cutanées à l'Ypérite. A propos de deux nouveaux cas.

Based on two of their own cases, the authors review the lesions produced by Yperite. This chemical agent produces cutaneous burns which are quite characteristic; histological study of biopsies carried out on cutaneous lesions was used to define the effects on the epidermis and dermis. The treatment of patients, with this rare condition, remains symptomatic.

[Breast-preserving treatment of breast cancer and peroperative curietherapy]. / Traitement conservateur du cancer du sein et curiethérapie peropératoire.

From May 1988 to December 1990, 35 patients benefitted from a breast-conserving treatment (tumor resection with at least 1 cm of free margin, axillary dissection and peroperative brachytherapy). The iridium sources were introduced 24 h later, delivering between 15 to 17.5 Gy. Three weeks later an additional course of external radiation delivered a dose of 50 Gy in 5 weeks to the whole breast. In this series, only very early breast lesions were included and no patient received additional chemotherapy. Due to the short period of observation, we only report on the acute side effects even if until now we have not seen any case of tumor relapse. We did not observe any major complications after this combined approach: only three patients developed a local infection requiring antibiotics. Esthetic evaluation is quite encouraging with all women showing good and excellent results from the physician's and patient's points of view. This approach seems to be quite interesting cosmetically as it allows to correct the breast shape while preserving an adequate position of the implant and so preserving a good oncological approach.

Carpal tunnel syndrome due to an haemangioma of the median nerve in a 12-year-old child.

A case of carpal tunnel syndrome due to an haemangioma of the median nerve in a 12-year-old male is reported. Radiological and histological data support a venous origin of the tumour. Interfascicular dissection and resection were performed, and 6 months later the patient remains symptoms free.

[Immediate breast reconstruction by musculocutaneous flap]. / Reconstruction mammaire immédiate par lambeau musculo-cutané.

Immediate breast reconstruction (IBR) after mastectomy is now quite frequent. To achieve this, an implant, in a complete muscular pocket, or a myocutaneous flap (latissimus dorsi, TRAM flap) can be chosen. Since 1983, 49 immediate breast reconstructions (11% of IBR) were performed with a myocutaneous flap in the Gustave Roussy Institute. In our experience, these techniques were principally performed because of the failure of conservative treatment (70%). Immediate complications were more frequently observed after immediate breast reconstructions with a TRAM flap (partial or minimal flap necrosis: 33%, infection: 13.5%). Late complications were more frequent in reconstructions with a latissimus dorsi flap: the prostheses were the main reasons (contracture III/IV: 25%, infection: 18%, deflation of the implant: 12%). The best long term results were described with the TRAM flap, and we now prefer this technique for immediate reconstruction with a flap.

Human orf.

Human Orf is an uncommon viral disease acquired through contact with infected sheep and goats. We report five cases of human Orf acquired while preparing mutton. The clinical picture and the management of human Orf are presented. Awareness of the benign nature of the condition is important in preventing ill-advised therapy.

[Analysis of 156 breast reconstructions by transverse rectus abdominis muscle flap (TRAM)]. / Analyse de 156 reconstructions mammaires par TRAM.

The myocutaneous rectus abdominis flap described by Hartrampf was used for 156 breast reconstructions between 1982 and 1992. 107 reconstructions were done with one pedicle. 142 were delayed reconstructions. Partial necrosis of the flap occurred in 10% of the cases in bipedicled flaps and 20% in unilateral flaps. No hernia occurred in this series. Cosmetic results are considered satisfactory or very satisfactory in 59% of the cases when evaluated by the medical team and 76.5% when evaluated by the patients. As a conclusion of this study, the TRAM flap is preferred in delayed reconstructions when local and general conditions are suitable, rather than latissimus dorsi flap reconstructions which require an implant.

[Carpal tunnel syndrome. Comparative studies of pre- and postoperative magnetic resonance and electromyography]. / Le syndrome du canal carpien. Etudes comparatives pré-et postopératoires entre résonance magnétique et électromyographie.

A comparative wrist study was conducted in a total of 36 subjects: 20 normal volunteers and 16 patients with diagnosed carpal tunnel syndrome. 1.5 Tesla MR was used with a cylindrical extremity coll. The authors reviewed the anatomy of the wrist in the normal subjects. The accuracy of MR diagnostic criteria for carpal tunnel syndrome was assessed in comparison with EMG results and surgical findings. The authors conclude that MRI has proved to be reliable and useful in the diagnostic work up of carpal tunnel syndrome. Its main indication would be in cases of negative or doubtful EMG.

[MRI of the wrist joint]. / IRM des poignets.

Due to the development of new surface coils and the use of thin slices, MRI has become an essential diagnostic tool in wrist pathology. After several technical considerations, the authors describe the normal MRI appearance of the various anatomical structures of the wrist, particularly the triangular fibrocartilaginous complex of the wrist and the elements of the carpal tunnel. They review the principal indications for MRI: chronic diseases such as carpal tunnel syndrome and traumatic ligamentous and cartilaginous lesions. The bone marrow lesions detected in the presence of occult fractures and osteonecrosis of the lunate or scaphoid are then briefly considered. The diagnostic criteria of median nerve compression (carpal tunnel syndrome) include morphological and signal changes in the nerve, abnormal palmar convexity of the flexor retinaculum and signs of tenosynovitis of the intracarpal flexor tendons. However, in practice, MRI is only useful when there is disagreement between the clinical and EMG findings and in postoperative recurrences, in which case it may reveal insufficient section of the retinaculum or the presence of exuberant postoperative fibrosis responsible for persistent nerve compression. Traumatic tears of the triangular fibrocartilage are characterised by a linear high signal intensity image (on T1 and T2 weighted sequences), usually situated in the periphery of the articular disk. Degenerative lesions tend to be central, within the disk and are frequently observed after the age of 40 years.

[Treatment of cleft lip and palate: long-term results]. / Traitement des fentes labio-palatines: résultats à long terme.

Since 1958, 900 children with cleft lip and palate were operated on at the University Hospital Brugmann in Brussels. Until 1981, the children were operated at 6 months for the lip and at 18 months for the palate with two flap palatoplasties. Since 1982, R. Malek's technique and sequence were adopted. The results after 5 years follow-up are analyzed between two groups of 50 and 49 children operated with the two techniques. Growth of the maxillary arch and phonation are well improved in the second group, but no improvement was observed in terms of hearing.

[Costolumbar pain, aneurysm of the renal artery and hypertension]. / Douleur costo-lombaire, anévrysme de l'artère rénale et hypertension.

Thrombosis of a renal artery aneurysm had provoked renal atrophy and secondary renovascular hypertension in a patient in whom rapid diagnosis was not possible from the abdominal symptomatology and results of biological tests. Investigation of lumbar pain should therefore include an IVU with or without subsequent renal arteriography, the rapid execution of these examinations being of primordial importance. Treatment was by nephrectomy, which allowed hypertension to be controlled and risks related to the aneurysm avoided.

Early dermabrasion for deep dermal burns by means of sandpaper

Deep dermal burns are initially difficult to evaluate. They sometimes even undergo spontaneous healing. We present our own experience concerning the use of dermabrasion with sandpaper, a veritable alternative to early scar excision. Skin grafts are not always called for. The aesthetic results are excellent. Dermabrasion should be systematically considered for all deep dermal burns and particularly for scalding burn mechanisms or facial burns (AU)