TRACHOMA 297 blindness. The estimated 31,424 persons in priority groups 4 and 5, 53.8 percent of the trichiasis and entropion, are at less or even no immediate risk of blindness. For the purposes of planning surgical intervention, it is useful to examine whether the relationship be- tween the proportion in priority groups 1, 2, and 3 (or groups 4 and 5) change across various segments of the population in Nepal. The distribution of the trichiasis and entropion surgical priority groups by terrain is shown in Table 7-44. In the terai and valley areas, slightly more than half (52.4%) of the trichiasis and entropion cases are in urgent need of lid surgery (i.e., in priority groups 1, 2, or 3). In the hills and mountains, less than half (41.3%) urgently need surgery. Overall, however, the terai and valleys have the same number of urgent surgeries as do the hills and mountains, approximately 13,000 persons. One-third (33.3%) of the trichiasis and entropion in Nepal, an estimated 19,408 cases, is of lower priority (priority groups 4 and 5) and occurs in the hills and mountains. TABLE 7--44. DISTRIBUTION OF TRICHIASIS AND ENTROPION (TIE) SURGICAL PRIORITY GROUP BY TERRAIN (NBS 1981) Estimated Population in Group Percentage of All TIE in Terrain Percentage of All TIE in Nepal Terrain and Priority Groupa Sample N Terai and valleys Priority 1-3 Priority 4-5 Hills and mountains Priority 1-3 Priority 4-5 84 43 41 92 38 54 25,242 13,227 12,015 33,086 13,678 19,408 100.0% 52.4 47.6 100.0 41.3 58.7 43.3% 22.7 20.6 56.8 23.5 33.3 Total 176 58,328 100.0 100.0 Source: FR7.005.3 AN.3 aPriority groups: 1. One eye blind and TIE in either eye. 2. No blindness and Stage 3 TIE in either eye. 3. No blindness and Stage 2 TIE in either eye. 4. No blindness and Stage 1 TIE in either eye. 5. Bilateral blind and TIE in either eye. Table 7-45 shows the distribution of the surgical priority groups by the four major regions of the country. In the East, Central, and West regions, the urgent priority groups (groups 1, 2, and 3) are more than half of the trichiasis and entropion, while in the Far West less than half of the trichiasis and entropion cases require
