Factors affecting eyelid crease formation before and after silicone frontalis suspension for adult-onset myogenic ptosis.

PURPOSE: To evaluate factors that affect eyelid crease formation before and after frontalis suspension. DESIGN: Nonrandomized, comparative, interventional case series. METHODS: Sixty-three patients (125 eyes) with myogenic ptosis were included. Data collected included age, gender, previous surgeries, follow up, as well as pre- and postoperative margin reflex distance, palpebral fissure height, and levator function. Intraoperative maneuvers of incorporation of the levator aponeurosis into the skin closure, conservative fat excision, and conservative skin excision were recorded. Pre- and postoperative eyelid creases were graded by 2 masked, independent observers as "good," "fair," or "poor." RESULTS: The weighted κ coefficient between the graders was 0.68 (95% CI, 0.58-0.79) preoperatively and 0.70 (95% CI, 0.61-0.79) postoperatively. Evaluating preoperative eyelid crease grades, there was no significant difference with regard to age or gender (p = 0.83 or 0.69, respectively). Eyelid crease grade correlated with margin reflex distance (p = 0.0004) and palpebral fissure height (p = 0.002). There was no significant correlation of eyelid crease with levator function (p = 0.104). After frontalis sling, intraoperative maneuvers of incorporation of the levator aponeurosis into the incision, skin preservation, and fat preservation correlated with postoperative eyelid crease (p = 0.0004, 0.059, and 0.033, respectively). CONCLUSIONS: Preoperative levator function in patients with adult onset myogenic ptosis may be an inaccurate measure of true levator palpebrae strength. Reliance on levator function alone in decision making for surgical intervention in these patients may be misguided. The inclusion of the intraoperative maneuvers of incorporation of the levator aponeurosis into the skin incision and preservation of fat and skin results in a stronger eyelid crease after frontalis sling surgery.

Ocular myeloid sarcoma in a 10-year-old child.

A 10-year-old girl presented with a 2-week history of an elevated, red conjunctival mass. She was in remission from acute myeloid leukemia (AML) and had two recurrences. Biopsy revealed a conjunctival myeloid sarcoma, an extramedullary lesion composed of cells of myeloid lineage that may present in children and adults, most commonly in the lymph nodes, skin, and subcutaneous tissues; it is less likely in ocular tissue. In patients with a history of AML, a new myeloid sarcoma is considered a relapse. To the best of our knowledge, this is the first case of a conjunctival myeloid sarcoma heralding a recurrence of an aggressive form of AML in a child.

Albinism in Africa as a public health issue.

BACKGROUND: Oculocutaneous albinism (OCA) is a genetically inherited autosomal recessive condition and OCA2, tyrosine-positive albinism, is the most prevalent type found throughout Africa. Due to the lack of melanin, people with albinism are more susceptible to the harmful effects of ultraviolet radiation exposure. This population must deal with issues such as photophobia, decreased visual acuity, extreme sun sensitivity and skin cancer. People with albinism also face social discrimination as a result of their difference in appearance. The World Health Organization is currently investigating the issues concerning this vulnerable population. METHODS: Systematic electronic search of articles in PubMed concerning albinism in Africa. Furthermore, a World Health Organization (WHO) pilot survey of albinism was drafted in English, French and Portuguese, and distributed to African countries through WHO African Regional Offices (AFRO) in an attempt to gather further information on albinism. RESULTS: Epidemiologic data on albinism, such as prevalence, were available for South Africa, Zimbabwe, Tanzania and Nigeria. Prevalences as high as 1 in 1,000 were reported for selected populations in Zimbabwe and other specific ethnic groups in Southern Africa. An overall estimate of albinism prevalences ranges from 1/5,000-1/15,000. In addition, both the literature review and the survey underscored the medical and social issues facing people with albinism. CONCLUSION: The estimated prevalence of albinism suggests the existence of tens of thousands of people living with albinism in Africa. This finding reiterates the need for increased awareness of and public health interventions for albinism in order to better address the medical, psychological and social needs of this vulnerable population.

Mutants with temperature-sensitive defects in the Escherichia coli mismatch repair system: sensitivity to mispairs generated in vivo.

We have used direct selections to generate large numbers of mutants of Escherichia coli defective in the mismatch repair system and have screened these to identify mutants with temperature-sensitive defects. We detected and sequenced mutations that give rise to temperature-sensitive MutS, MutL, and MutH proteins. One mutation, mutS60, results in almost normal levels of spontaneous mutations at 37 degrees C but above this temperature gives rise to higher and higher levels of mutations, reaching the level of null mutations in mutS at 43 degrees C. However, at 37 degrees C the MutS60 protein can be much more easily titrated by mispairs than the wild-type MutS, as evidenced by the impaired ability to block homologous recombination in interspecies crosses and the increased levels of mutations from weak mutator alleles of mutD (dnaQ), mutC, and ndk. Strains with mutS60 can detect mispairs generated during replication that lead to mutation with much greater sensitivity than wild-type strains. The findings with ndk, lacking nucleotide diphosphate kinase, are striking. An ndk mutS60 strain yields four to five times the level of mutations seen in a full knockout of mutS. These results pose the question of whether similar altered Msh2 proteins result from presumed polymorphisms detected in tumor lines. The role of allele interactions in human disease susceptibility is discussed.