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.

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.

[Analysis of 156 breast reconstructions by transverse rectus abdominis muscle flap (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.

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.

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.

[Immediate breast reconstruction by musculocutaneous flap]

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.

[Breast-preserving treatment of breast cancer and peroperative curietherapy]

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.

[Treatment of cleft lip and palate: long-term results]

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.

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.

[Cutaneous burns caused by Yperite. Apropos of 2 new cases]

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.

[Launois-Bensaude disease. Apropos of 2 new cases]

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.