ABNORMAL CORNEAS MEASURED BY A NEW PHOTOGRAMMETRIC TECHNIQUE

The limitations of keratometry and photokeratoscopy are briefly discussed. A new photogrammetric technique of measuring corneal topography is described. Contours and cross-sections of abnormal corneas are presented to illustrate the scope and application of the new technique.     

Vitamin D replacement in Asians with diabetes may increase insulin resistance.

We report three cases of vitamin D replacement in British Asians with vitamin D deficiency and non-insulin-dependent diabetes mellitus. In all cases, replacement resulted in an increase in insulin resistance and a deterioration of glycaemic control.     

Fornix transection impairs conditional visuomotor learning in tasks involving nonspatially differentiated responses.

Rhesus monkeys learned a series of conditional visuomotor associations involving two-dimensional "objects" that instructed one of three responses: tapping a touch screen, steady contact with the screen for a brief period, or steady contact for a longer period. Relative to controls, fornix-transected monkeys were impaired in the acquisition of new associations and in the retention of preoperatively learned ones. These findings challenge the view that the hippocampal system participates in associative learning only when spatial information is relevant to either the stimulus or the response.     

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: Fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring timeconsuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families, using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosomal deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available. © 1995 Wiley-Liss, Inc.     

Sperm quality in Hodgkin's disease versus non-Hodgkin's lymphoma

The study was conducted to determine the deleterious effect of lymphoma disease on spermatogenesis and to evaluate the possibility that the disease is mediated primarily by inherent mechanisms in Hodgkin's disease and non-Hodgkin's lymphoma patients. A total of 89 patients with lymphoma disease (Hodgkin's and non-Hodgkin's) were referred for sperm preservation prior to adjuvant treatments. A comparison was made of pre- and post-thaw sperm quality between lymphoma patients and healthy volunteers who applied for sperm donation. This was followed by further assessment of the differences between patients with Hodgkin's disease and non-Hodgkin's lymphoma in terms of sperm variables, clinical parameters and blood hormone concentrations. It was found that patients with lymphoma disease had significantly impaired pre-freeze and post-thaw sperm quality compared with that of healthy volunteers. Patients with non-Hodgkin's lymphoma had spermatozoa of higher quality than patients with Hodgkin's disease. No differences were found in the clinical or hormonal parameters between these two groups. As expected, reduced testicular size and abnormal testicular consistency were correlated with decreased sperm quality. The mere presence of cancer disease has a direct negative effect on spermatogenesis, which is probably not related to incidental side-effects. A variable degree of impairment should be expected with different categories of cancer.      

Antibodies to low-incidence antigens and elimination of the antihuman globulin phase of the crossmatch-case report: anti-Wra

An antibody to a low-incidence antigen was identified in the serum of a nontransfused male patient. The antibody was subsequently identified as anti-Wra and was only detectable at the antihuman globulin (AHG) phase of the crossmatch. Instances of severe hemolytic transfusion reactions have been reported following the transfusion of red blood cells containing low-incidence antigens in patients with antibodies directed toward these antigens (e.g., anti- Wra, -Cob, -Jsa, etc.). Elimination of the AHG phase of the crossmatch can result in either risks or benefits. Since patients seen at this facility primarily have been multitransfused or are multiparous females, the AHG phase of the crossmatch has been maintained.     

Surgonomics: the cost dynamics of craniotomy

Prospective payment systems using the diagnostic related group (DRG) mechanism are being phased in for Medicare inpatient hospital care. The purpose of this study was to examine a common neurosurgical procedure (001), craniotomy without trauma, and characterize the cost dynamics of this DRG. All patients (n = 50) treated in this DRG at the Long Island Jewish Medical Center during 1983 had their financial charges exclusive of physician fees examined. The findings were: (a) each hospital service category had wide charge variances around the mean; (b) emergency (ER) admissions were 200% more expensive than nonemergency (non-ER) admissions; (c) ER admissions seemed to have no greater severity of illness than non-ER admissions, but had a significantly different referral pattern (i.e., admission from the ER to a nonneurosurgical service with a subsequent neurosurgical referral); (d) this DRG when grouped into clinical "subproducts" (i.e., craniotomy for tumor, hematoma, hydrocephalus, aneurysm, benign cyst, and other) showed marked charge differences; and (e) the most expensive 25% of patients had five times higher charges than the least expensive 25% for both ER and non-ER admissions. This type of financial analysis may give surgeons a methodology with which to address the problems of cost containment in a more serious manner.