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In this paper, a methodological approach to the classification of tumour skin lesions in dermoscopy images is presented. Melanomas are the most malignant skin tumours. They grow in melanocytes, the cells responsible for pigmentation. This type of cancer is increasing rapidly; its related mortality rate is increasing more modestly, and inversely proportional to the thickness of the tumour. The mortality rate can be decreased by earlier detection of suspicious lesions and better prevention. Using skin tumour features such as colour, symmetry and border regularity, an attempt is made to determine if the skin tumour is a melanoma or a benign tumour. In this work, we are interested in extracting specific attributes which can be used for computer-aided diagnosis of melanoma, especially among general practitioners. In the first step, we eliminate surrounding hair in order to eliminate the residual noise. In the second step, an automatic segmentation is applied to the image of the skin tumour. This method reduces a colour image into an intensity image and approximately segments the image by intensity thresholding. Then, it refines the segmentation using the image edges, which are used to localize the boundary in that area of the skin. This step is essential to characterize the shape of the lesion and also to locate the tumour for analysis. Then, a sequences of transformations is applied to the image to measure a set of attributes (A: asymmetry, B: border, C: colour and D: diameter) which contain sufficient information to differentiate a melanoma from benign lesions. Finally, the various signs of specific lesion (ABCD) are provided to an artificial neural network to differentiate between malignant tumours and benign lesions.

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UNLABELLED: Seventeen subjects (16 male, 1 female) with a mean age of 60 +/- 7 years were studied. INCLUSION CRITERIA: severe chronic bronchitis (mean FEV1 = 960 ml with frank hypoxaemia (PaO2 less than 60 mmHg); past history of right heart failure or electrical signs of right ventricular hypertrophy or pulmonary hypertension (PAP greater than 20 mmHg); oxygen therapy at home for greater than 10/24 hours (most often greater than or equal to 12 hours) for more than a year; interval of more than 6 months between the first haemodynamic investigation (before the start of O2) and the last, this period being on average 23.9 +/- 18.6 months. From a clinical standpoint, there were 5 deaths occurring 11 to 30 months after the start of O2. Effort dyspnoea was stable or worsened but hospitalisations for cardiorespiratory decompensation were less frequent than before the start of O2. There were no significant changes in arterial blood gases: PaO2 rose from 51.9 +/- 8.1 to 52.5 +/- 7.0 mmHg. PAP improved in 12 cases out of 17, and for the group as a whole the difference was not statistically significant. However in the sub-group where the daily duration of administration was greater than 12/24 hours (n = 7), PAP improved in all the individual cases and fell on average from 26.4 +/- 6.8 to 19.9 +/- 3.4 mmHg (p less than 0.02) whilst in the 10-12 hours sub-group there was no mean change in PAP.(ABSTRACT TRUNCATED AT 250 WORDS)

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In communities with endemic blinding trachoma, mass (or "blanket") treatment with a topically applied tetracycline derivative is a standard control measure. The widely used "intermittent" treatment schedule consists of the twice daily application of antibiotic ointment for five consecutive days once a month for six months. In this study, the efficacy of "intermittent" treatment was evaluated for the treatment of severe and moderate intensity trachoma in children in southern Tunisia. Tetracycline or erythromycin ointments (specific antichlamydial drugs) were compared with 5% boric acid ointment (a simple antiseptic) given by the intermittent schedule during the winter and spring. There was a statistically significant degree of improvement at only one examination, four weeks after the full course of treatment had been completed. When re-examined five months later there were no differences in intensity in the three groups. The limited effect of topical chemotherapy might be attributable to several causes, among which could be inadequate drug levels, inadequate treatment periods, reinfection from non-treated children in the community, and auto-infection from extraocular sites (e.g., respiratory tract) in the same child. The possible value of short-term (two weeks) systemic antimicrobial therapy as an additional strategy to prevent blindness of children with potentially blinding active trachoma is discussed.

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In two villages in southern Tunisia where trachoma was endemic 7 per cent and 14 per cent of adults respectively had visual acuity of 20/400 or less. In both villages active trachoma affected most children under the age of two, reached a peak in two- to five-year-olds, then declined to age 15. The chronic inflammatory disease in childhood appeared to produce irreversible scarring of the eyelids, and loss of vision occurred in adult life due to corneal scarring caused by inturned eye lashes and loss of tears (dry-eyed syndrome). Economic development in one village was associated with a decline in active, infectious disease. In the second village, whose traditional economy was unchanged, there was the same prevalence of active disease over a three-year period. Unless economic development or public health control programmes reduce the prevalence of severe and moderate trachoma children now affected will develop the same blinding lesions as their parents. With the increasing numbers of children who survive there will probably be a dramatic increase in the numbers of the blind from trachoma in 10 to 20 years. Since active inflammatory trachoma in childhood responds to tetracyclines, erythromycin, and sulphonamides the disease should be attacked in those undeveloped rural areas where it continues to lead to blindness.

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Herpes simplex keratitis was found to be a common ophthalmic problem in Tunisia. Dendritic and geographic ulcers were complicated by deep stromal keratitis in 31% of patients, two thirds of whom were known to have been treated previously with corticosteroids. Herpes simplex virus was isolated from 41% of patients from whom corneal material was cultured. To develop an effective program for management of epithelial herpes in developing countries, treatment with idoxuridine was compared with debridement and patching. Average healing time for 31 ulcers treated with idoxuridine was 13 days, with three treatment failures; average healing time for 20 ulcers treated with debridement and patching was five days, with one failure. Debridement and patching of herpetic ulcers was an efficient way to treat herpes simplex keratitis within the context of overall medical care in Tunisia.

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Acute hemorrhagic conjunctivitis (AHC), a new disease entity first reported in 1969, has since become pandemic throughout the world. In Tunisia during an epidemic in 1972 to 1973 we studied 25 cases of AHC, which were characterized by explosive onset of lid edema, chemosis, conjunctival hemorrhages, follicular hypertrophy, and epithelial keratitis. Clinical signs peaked in 48 hours and cleared without sequelae in five to seven days. Paired acute- and convalescent-phase sera from six of the patients showed a rising titer of neutralizing antibody to the prototype strain of AHC virus (J6 70/71), which was isolated in Japan. Two viral isolates from Tunisian patients were also antigenically related to the Japanese strain, indicating that a single etiologic agent (a new member of the picornavirus group) is probably responsible for the current pandemic of AHC.

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A controlled chemotherapy trial of trachoma was carried out in a Tunisian oasis among schoolchildren with active disease. We compared 1% tetracycline ointment (79 patients) or 1% rifampicin ointment (76 patients) with 5% boric acid ointment (79 patients). Medications were administered twice daily, six days a week, for ten weeks. Slit-lamp examinations by three ophthalmologists were made independently before treatment as well as five, 19, and 39 weeks after treatment. Bacteriologic cultures were taken during treatment as were smears to detect trachoma agent at each clinical examination. Five weeks after treatment, the intensity of conjunctival disease in the tetracycline and rifampicin groups was reduced significantly when compared with boric acid, but at 19 weeks this suppression was found only in the tetracycline group. Ocular bacterial pathogens were eliminated almost entirely in the two antibiotic groups during treatment. The initial prevalence of trachoma (29to 31%) was significantly reduced in the two antibiotic-treated groups at five weeks and 19 weeks after treatment. The prevalence of trachoma was equally low (7%) in all three groups following retreatment with tetracycline. Although both antibiotics were effective, rifampicin offered no advantage over tetracycline in this trial. Recurrent disease in this school-based treatment study probably was due to reinfection from younger siblings at home. While systematic, community-wide, antibiotic treatment programs are not always possible in countries where trachoma is endemic, limited antibiotic therapy programs should be continued in these areas to reduce the intensity and prevalence of trachoma, even though the disease cannot be eradicated.

PIP: In this study, the authors compared topically applied tetracycline or rifampicin ointment with boric acid ointment administered for 10 weeks for its effect on endemic trachoma. 234 children with active disease were included in the treatment study. Those with the active disease were divided into 2 groups containing equal numbers each of the 3 intensity categories. Then each group was assigned to 1 of 3 treatment categories. Medication was administered twice daily over a single 3-hour class period and a 70-day course of follow-up therapy with 1% tetracycline was provided once daily for all the children 25 weeks after completion of the initial treatment. 62 (26.5%) had severe trachoma and 133 (56.8%) had trachoma of moderate intensity. In March 1972, 5 weeks after treatment completion, the trachoma in the 2 groups treated with antibiotics was less severe compared with the boric acid group. However, by June 1972, only the tetracycline group had less active trachoma than the boric acid treated group. By this time, also, the 3 groups were equally improved. Following the 2nd course of tetracycline treatment 25-35 weeks after the initial trial, there were no differences in any of the groups. 2 courses of therapy, therefore, were no more advantageous than 1. In Giemsa-stained smears prior to treatment, the prevalence of positive smears for Chlamydia agent were similar in the 3 groups; following treatment, prevalence had dropped to 7% overall and then after retreatment, there were rarely any cases in any of the treated groups. While the 2 antibodies were significantly better than boric acid, rifampicin did not seem to offer any significant advantages over tetracycline. The prevalence of trachoma agent appeared to change more readily than the clinical disease. Clearly the pattern of disease intensity and microbial infection displayed a seasonal cycle thatmust be considered when evaluating antibiotic treatment efficacy. The prevalence of trachoma decreases with age and that, along with the seasonality, contribute to the disease intensity. In this study, treatment did alter the disease temporarily but did not affect its course in the long run since environmental factors which originally produced the disease had not changed. Only communitywide chemotherapy would have a significant effect. However, antibiotic treatment is necessary to reduce the occurrence of later complications.

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Microscopical examination of 927 Giemsa-stained conjunctival smears from children with chronic trachoma in southern Tunisia showed 93 (10 per cent.) with typical trachoma (chlamydial) inclusions in epithelial cells. The accompanying cytological features were a useful indicator for inclusions. Inclusions were found only in slides with numerous polymorphonuclear neutrophils (PMNs) and separation of the epithelial cells. When these two features alone were present, 3 per cent. of the smears were inclusion-positive; when many lymphocytes were present also, 25 per cent. were inclusion positive; when other cytological features (plasma cells, macrophages, blastoid, and stem cells) were present as well, 70 per cent. of the smears were inclusion-positive. The occurrence of these sets of cytological features can be a useful guide for selecting smears for intensive examination for chlamydial inclusions. Immunofluorescent (FA) staining and Giemsa staining of 527 pairs of matched smears detected trachoma agent in 67 (13 per cent.); in thirty by both methods, in thirteen by Giemsa staining alone, and in 24 by FA alone. The examination of Giemsa-stained smears for chlamydial inclusions is a useful technique for the diagnosis of trachoma or inclusion conjunctivitis by laboratories that do not have the specialized facilities for the identification of these chlamydial infections by the technically more complex procedures of immunofluorescent staining or isolation in embryonated eggs or tissue cultures.

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Media for isolation of Haemophilus sp. from the conjuctiva were compared in an oasis in southern Tunisia where severe trachoma and seasonal epidemic purulent conjunctivitis are common. Of 89 children tested, IsoVitaleX-supplemented chocolate agar yielded Haemophilus in 87%, plain chocolate agar in 75%, sheep blood agar with a stab of Staphylococcus epidermidis in 74%, and Fildes medium in 58%. Since other microbial pathogens are easily identified in the modified blood agar, it was the most useful single medium.

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