The pattern evoked response in disorders of the optic nerve

The pattern evoked electroretinogram (PERG) was investigated in 11 patients with unilateral optic nerve disease and in a series of age-matched controls. The visually evoked potential (VEP) was also measured. The PERG showed a similar reduction to the VEP in optic nerve disease. Serial studies indicate that the PERG may not be affected immediately in some instances but may show a gradual decline over several months.     

COSTING ACUTE MYOCARDIAL INFARCTION IN NEW SOUTH WALES,AUSTRALIA, BASED ON INCIDENCE RATHER THAN PREVALENCE METHODS

Estimating the economic costs of a disease is an important prerequisite to determining the costs and benefits of various preventive programs. For preventive programs, incidence-based costing is a more appropriate means of estimation than is prevalence-based costing. In this study the cost of acute myocardial infarction (AMI) in New South Wales has been estimated using an incidence-based approach. The calculated cost of AMI in 1979 was $301.0 million, made up of $32.3 million as direct costs and $268.7 million as indirect costs. In a sensitivity analysis, the cost was shown to be most sensitive to the incidence of AMI, the discount rate, and the assumption of a wage for housework. Both the direct costs and indirect costs per case are substantially higher in the United States than in Australia, and this reflects higher physician charges, higher hospital costs, and in the case of indirect costs, higher average weekly earnings.     

1-Methyl-4-(2'-methylphenyl)-1,2,3,6-tetrahydropyridine (2'-CH3-MPTP) is a more potent dopaminergic neurotoxin than MPTP in mice

The administration to mice of 1-methyl-4-(2'-methylphenyl)-1,2,3, 6-tetrahydropyridine (2'-CH3-MPTP), a substituted analog of the dopaminergic neurotoxin MPTP caused even more dopaminergic toxicity than MPTP itself. Under conditions in which MPTP was relatively ineffective (i.e. two injections per day of 0.113 mmol/kg at an interval of 6 h for one or two days), 2'-CH3-MPTP caused a very large decrement in the neostriatal content of dopamine and its metabolites and a corresponding decrement in the capacity of a neostriatal synaptosomal preparation to take up [3H]dopamine. Moreover, 2'-CH3-MPTP administration (as few as four injections) caused a virtually complete loss of nerve cells in the zona compacta of the substantia nigra. This compound, like MPTP, may prove to be a valuable research tool.     

Central and peripheral changes in catecholamine-synthesizing enzyme activities after systemic administration of the neurotoxin DSP-4

In brain regions containing noradrenergic (NA) cell bodies or terminals, DSP-4 induces changes in the activity of catecholamine-synthesizing enzymes which suggest that central NA neurons are lesioned by this neurotoxin. In contrast, the lack of change in the same enzymatic activities in an area containing mostly adrenergic (A) neurons (C2 region), favors the hypothesis of a resistance of the A neurons to DSP-4. Furthermore, the enzymatic changes observed in peripheral organs suggest a peripheral activation of the NA cell bodies in response to lesioning of the sympathetic terminals by DSP-4.     

The galea fascia flap in orbital reconstruction: innovative harvest technique.

AIM: To report the treatment of a recurrent adenoid-cystic carcinoma of the lacrimal gland required orbital exenteration with an en bloc resection of the lateral orbital rim and wall and an anterior portion of the temporal muscle. Reconstruction was planned with both the objectives of a shortened healing time for faster epithetic reconstruction and no visible scars. METHOD: After a cranially extended temporal approach, the dissection of the superficial galea layer was connected with the subcutaneous dissection of the upper and lower eyelid after subciliary incisions. RESULTS: Ample exposure of the temporal, frontal and orbital region was obtained, facilitating the orbital exenteration with en bloc resection of the lateral orbital rim and wall and the anterior portion of the temporal muscle. The epithelialization of the eye socket covered with the galea fascia flap was accelerated, providing faster epithetic reconstruction, without visible scars. CONCLUSIONS: Healing time is accelerated, providing faster epithetic rehabilitation without visible scars, which is important in the postoperative rehabilitation ladder after eye exenteration for both patient and surgeon. Further more ablative surgery within this region gets safer and easier due to the ample exposure of this innovative surgical technique. Further evaluation of the effectiveness and safety of this new approach is advisable.     

CT appearances of hydatid disease at various locations

Hydatid disease has characteristic imaging features on CT, which allow accurate preoperative diagnosis in most cases. However, when it occurs at unusual locations the diagnosis is often difficult, especially as the imaging appearance varies at different sites. In this article we have presented a pictorial review of the CT features of disease due to Echinococcus granulosus at various sites in the human body.