[Post-traumatic glaucoma with irido-corneal angle injuries in Cameroon]. / Le glaucome post-traumatique a angle ouvert au Cameroun.

AIM: To study the particularities of late post-traumatic glaucoma with irido-corneal angle injuries in black Cameroonians. MATERIAL AND METHODS: Retrospective analysis of 1343 files of glaucomatous patients was carried out from January 1991 to December 2001 at the Douala General Hospital in Cameroon in Central Africa. Fifty seven of them had post-traumatic glaucoma. Of these 28 were secondary to irido-corneal angle injuries. RESULTS: The prevalence of post-traumatic glaucoma related to irido-corneal angle injuries in our population was 2.1%. The mean patients age was 45.9 +/- 18.3 years (range, 17 to 67 years). The time from injury to diagnosis ranged from 1 year 4 months to 7 years (median: 3.7 years). The follow-up period ranged from 3 months to 5 years 6 months, with a mean of 1.7 +/- 1.9 years. The prevalence of monocular blindness was 61.9% and 81% at the first and last examination respectively. The mean intraocular pressure was 36.9 +/- 13.8 mmHg (range: 22 and 66 mmHg) at the first examination and 24.3 +/- 13 mmHg (range: 12 and 29 mmHg) at the last examination. The mean recorded cup/disc ratio was 0.8 +/- 0.2. It was equal to 1.0 in 61.9% of cases. Irido-corneal angle recession was the most common lesion (61.9%) followed by iridodialysis (38.1%) and cyclodialysis (14.3%). Normalization of the intraocular pressure was achieved with medical treatment in 23.8% and with trabelectomy in 12.3% of the cases. Neovascular glaucoma was found in 4.8% of the cases. CONCLUSION: The treatment of secondary post-traumatic open angle glaucoma is disappointing. The patients are young, the disease is advanced, and the compliance and follow-up are poor. The prevention of post-traumatic glaucoma is based on the control of ocular trauma and the periodic follow-up of patients with and history of non perforating injury of the eye.

[Autologous blood injections for treating hypotonies after trabeculectomy]. / Injections de sang autologue dans les hypotonies après la trabéculectomie.

The authors carried out a retrospective study in order to assess the efficacy of intrabled autologous blood injections after trabeculectomy. The indication for treatment was hypotony associated with overfiltration. Twelve eyes of 12 patients including seven men (58.3%) and five women (41.67 %) underwent from one to four (mean 1.7) subconjunctival injections. The age of the patients ranged from 31 to 66 years (mean 52.4 years). All the patients were diagnosed with open-angle glaucoma. Three eyes underwent trabeculectomy with mitomycine C, one with 5-fluorouracil and eight with no antimetabolite. The mean post-needling period was 12.3 months (ranging from 7 to 28 months). After intrabled blood injections, the average intraocular pressure increased from 2.7 1.2 mmHg (ranging from 0 to 6 mmHg) to 8.2 4.2 mmHg (ranging from 4 to 16 mmHg). The difference was statistically significant (P < 0.5). After treatment, the average visual acuity increased from 1.8/10 to 3.2/10. This difference was not statistically significant (P > 0.5). However, the procedure was ineffective in two patients (16.7%) as regards intraocular pressure and in seven patients (58.3%) as regards visual acuity. Hyphema, the most frequent complication (58.3% of our cases) is usually small, transient, and without sequelae. Although it may be delayed, it may be important and it induce intraocular hypertony (10% of our cases) or it may be associated with intravital blood.

Effect of repeated ivermectin treatments on ocular onchocerciasis: evaluation after six to eight doses.

In 26 villages (1987 population 12,302), hyperendemic for savanna onchocerciasis in North Cameroon, ivermectin was distributed annually between 1987/89 and 1995. Each year until 1992, ophthalmologic examinations were performed before treatment. A final examination was made in 1995. The effects of ivermectin on ocular onchocerciasis were assessed by following (a) the ophthalmologic indices in three cohorts of males recruited before treatment in 1987, 1988 and 1989, who were treated and examined annually, and (b) the indices recorded yearly in the cross-section of males aged 15-19 years. The indices in 1995 from patients who had received up to eight doses were compared with those calculated before treatment in individuals of similar age. In the cohorts, the prevalences of microfilariae in the anterior chamber (MFAC) and of punctate keratitis (PK) recorded in 1995 were markedly reduced; there was a non-significant decrease in sclerosing keratitis (SK), and a significant worsening in the fundus indices in the cohorts. The cross-sectional analysis showed significant decreases in the prevalences of MFAC, PK and SK, and a significant increase in the mean visual acuity; there was no significant change in any fundus index. The findings suggest that repeated ivermectin treatment does not prevent the appearance of initial retinal lesions or the worsening of existing retinal lesions.

Onchocerca ochengi: epidemiological evidence of cross-protection against Onchocerca volvulus in man.

In North Cameroon, the vector of Onchocerca volvulus (causative agent of human onchocerciasis) also transmits 2 filariae of animals: O. ochengi from cattle and O. ramachandrini from wart hogs. In order to assess the qualitative and quantitative roles of these 'animal filariae' in the epidemiology of O. volvulus, the transmission of the 3 parasites was measured in 2 villages and related to the endemicity of human onchocerciasis. In Galim, a cattle-farming Guinea savanna village where wild animals are rare, the overwhelming majority of all filarial infections found in the Simulium damnosum s.l. vectors throughout the year were O. ochengi (89%). The remaining infections were mainly O. volvulus (10.5%), and a few O. ramachandrini (0.5%). In Karna, a crop-farming Sudan savanna village where cattle are rare, but wild animals common, flies were also more frequently infected with animal filariae than with the human parasite. In the dry season, when nomadic cattle are present, 54% of all infections were O. ochengi, 36% O. volvulus and 10% O. ramachindrini. In the rainy season, when the cattle move away, flies were mainly infected with O. ramachandrini (52% of all infections) and secondly with O. volvulus (48%). In Karna, the relationship between the Annual Transmission Potential (ATP) of O. volvulus and its prevalence in the human population conformed to other onchocerciasis foci, in that a moderate ATP led to hyperendemic onchocerciasis. In Galim, however, a 7-fold higher O. volvulus-ATP (caused by a very high biting rate of the flies) contrasted with a strikingly low endemicity of onchocerciasis. Since, at the same time, in Galim the transmission of O. ochengi (measured on man) was very high (15,000 L3/fly collector/year), we hypothesize that the reduced endemicity of onchocerciasis in Galim is due to 'natural heterologous vaccination' by the large annual number of O. ochengi-L3, inoculated into man by anthropo-boophilic S. damnosum s.l. The importance of micro-epidemiology for the understanding of the interlinkage of human and animal onchocerciasis is discussed.

[Intraocular pressure in a young Cameroonian population]. / Etude de la pression intraoculaire dans une population de jeunes Camerounais.

Glaucoma is one of the major causes of blindness throughout the world; mostly because patients come to consultation late. We performed a prospective study of the intraocular pressure, fundus and perimetry in 307 young Cameroonians (20 to 39 years old). Glaucoma was found in 5.8% of cases. This study shows that the disease appears early in black people and must be detected in patients under 40 years old.

Pterygium: epidemiological, clinical and therapeutical aspects at the Douala General Hospital.

Authors report the results of a retrospective study of epidemiological, clinical and therapeutical aspects of pterygium carried at the ophthalmological service of the Douala General Hospital. During the period of the study, 167 patients with pterygium were registered, which means a prevalence of 1.10%. The mean age of the patients was 41.76 years with standard deviation of 10.89. The noticed that men were a little bit predominant as compared to women with respectively 54.8% and 45.2% of cases. The pterygium were in the nasal side in 93.66% of cases and bilateral forms represented 31.73% of cases. 67 eyes were operated by excision technic more often associated to conjunctival translation. The relapse rate at 6 months was 7.44%. Authors recommend: 1 degree)-not to operate small and non-evaluative pterygium 2 degrees)-to use a magnifying system and if possible the operatory microscope 3 degrees)-to institute systematically an early, intensive, prolonged but degressive corticotherapy after surgery. 4 degrees)-to prescribe tinted or photochromic glasses to patients.

A study of onchocerciasis with severe skin and eye lesions in a hyperendemic zone in the forest of southwestern Cameroon: clinical, parasitologic, and entomologic findings.

Prior to the initiation of an onchocerciasis control program based on the mass administration of ivermectin in the rain forest of southwestern Cameroon, a preliminary baseline study of the area was conducted. The results of this study showed that onchocerciasis was hyperendemic in the area. Skin symptoms and signs were observed including pruritus (67.4% of the population examined), onchocerca nodules (51.6%), skin depigmentation (18.5%), and hanging groins (5.7%). Except for pruritus, the prevalence of these symptoms increased with age. Of the eyes examined, 44.9% had microfilariae in the anterior chamber, 33.5% had choroidoretinitis, 28.0% had punctate keratitis, 8.3% had papillary abnormalities, and 3.6% had sclerosing keratitis. Vision in 10.5% of the eyes examined was classified as blind or very poor (visual acuity = 0-0.10), in 15.7% as poor (visual acuity = 0.11-0.39), and in 73.8% as good (visual acuity = 0.4-1.00). Unlike previous reports that have linked serious ocular damage mainly to savanna onchocerciasis, the present study showed that forest onchocerciasis also caused significant ocular pathology, including blindness. Parasitologically, positive skin snips were recorded for 92.7% of the persons examined, with both sexes being equally infected. The parasite load, expressed as the geometric mean number of microfilariae per skin snip, was 53.6, and was much higher in males than in females. The flv vector, Simulium squamosum, had a high infection rate of 7.5% infective females in Bakumba and 6.8% infective females in Ngbandi, the two fly-catching points. The transmission potential was 266 infective larvae per person per month in Bakumba and 189 in Ngbandi.

A community-based trial of ivermectin for onchocerciasis control in the forest of southwestern Cameroon: clinical and parasitologic findings after three treatments.

In the onchocerciasis-endemic rain forest area of the Rumpi Hills in southwestern Cameroon, a community-based trial of ivermectin, given either once or twice a year over a three-year period (1988-1991), confirmed that the drug is a potent microfilaricide. The side effects recorded following the first treatment were edema, fever, pruritus, generalized body pains and lymphadenitis. Following subsequent treatments, the same adverse reactions were recorded, but these were generally milder when compared with those of the first treatment. The prevalence of skin microfilaria (mf) was more reduced in zone two, in which treatment was given every six months (76.9% reduction at the end of one year) than in the zone one, in which treatment was given once a year (7.4% reduction). In both zones, the impact of the drug in reducing the intensity of infection was more significant than that for prevalence. Besides pruritus, other skin symptoms were not significantly modified by ivermectin treatment. Ivermectin reduced the prevalence of ocular mf as well as the mf load of the anterior chamber of the eye, resulting in improvement of certain eye lesions such as punctate keratitis, anterior uveitis, and papillary anomalies. There was also some improvement in visual acuity. The level of participation of the village populations was somewhat low, ranging from 52% to 66%, despite excitement over the drug's additional benefit of expelling intestinal round worms.