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Biomedical subjects

M A Vickers

Publications and source records attributed to M A Vickers.

46 records · Page 3Linked to original sources

Corpora cavernosa ultrastructure in vascular erectile dysfunction.

Open biopsy of the corpus cavernosum was performed in 13 nondiabetic patients with erectile dysfunction. The history and physical examination, sleep rigidity and tumescence monitoring, hormonal assays, duplex ultrasonography with papaverine, and cavernosometry and cavernosography, formed the basis of categorizing each patient into 1 of 5 etiological groups. These groups included neurogenic, moderate arterial, severe arterial, venous and fibrotic causes for organic erectile dysfunction. The cavernous smooth muscle and endothelium in each patient appeared to be normal on light and electron microscopy. We conclude that cavernous biopsy is of limited value to determine therapeutic options in patients with erectile dysfunction.

Biopsy↗

Alpha thalassaemia in two Spanish families.

Two Spanish families with alpha thalassaemia, including 4 individuals with Hb H disease, are described. DNA mapping shows that, in addition to the common alpha thalassaemia determinant (-alpha 3.7), a different and previously unreported allele is present in each family. In one, there is a deletion of 10.5-12 kb of DNA including both alpha genes (--SPAN). In the other, a deletion of more than 100 kb has removed the entire alpha globin gene complex (--BR).

Alleles↗

Sexual impotence caused by vascular disease: diagnosis with duplex sonography.

We used duplex Doppler sonography to assess the hemodynamic function of the penis in patients with impotence to determine if there is arterial disease or if the veins are incompetent. The penis was scanned in the flaccid state, then again after erection was induced by intracorporal injection of papaverine. The diameter of each cavernosal artery was measured before and after injection and, by using Doppler sonography, the maximal systolic velocity in each cavernosal artery was measured. The Doppler gate was placed over the dorsal vein to detect any flow in that vein signifying venous leakage. The Doppler gate then was placed over the cavernosal veins in an attempt to detect cavernosal venous incompetence. Forty-five men with impotence were included in the study. In 39 patients, the cause of impotence was confirmed by other studies. The diameter of the cavernosal arteries and the increase in diameter of these arteries after induction of an erection were similar in all diagnostic groups. The peak systolic velocity, however, was decreased in patients with arterial insufficiency as compared with the velocity in normal subjects. In normal subjects, the mean peak velocity was 47 +/- 9 cm/sec; in patients with mild to moderate arterial insufficiency it was 35 +/- 16 cm/sec; in patients with severe arterial insufficiency it was 7 +/- 8 cm/sec. The difference in peak velocities between the right and left cavernosal arteries after papaverine injection (asymmetric arterial response) was significantly larger in patients with mild to moderate arterial insufficiency than in other diagnostic groups. Four patients with venous incompetence had detectable flow in the dorsal vein, but no flow could be detected with Doppler sonography in the cavernosal veins in any patients, including those who were proved to have significant cavernosal venous leaks. Our findings suggest that Doppler measurement of maximal systolic velocity in the cavernosal arteries after papaverine injection is an accurate indicator of arterial function. Asymmetric flow in the cavernosal arteries also suggests some degree of arterial insufficiency. Diameters of the cavernosal arteries and their increase after injection are not predictive of arterial patency. Doppler sonography cannot show cavernosal venous leakage, but in some cases it can show dorsal venous incompetence.

Blood Flow Velocity↗

Characterization of two deletions that remove the entire human zeta-alpha globin gene complex (- -THAI and - -FIL).

We have fully characterized two alpha thalassaemia mutants that occur in Southeast Asia, - -THAI and - -FIL. Each mutant is due to a deletion that removes the entire zeta-alpha-globin gene complex. Localization of the 5' breakpoints described here, allows the identification of unique fragments that are specific for each of the two mutations. This information can be used to assess the frequency of these mutants in Southeast Asia and will be of value in prenatal testing for alpha thalassaemia in this area.

Child, Preschool↗

Infective endocarditis affecting the eustachian valve.

A previously fit 44 year old man presented with acute staphylococcal pneumonia. Despite appropriate antibiotics he showed signs of continuing sepsis and eventually died. At necropsy endocarditis of the eustachian valve was found.

Adult↗

Creation and use of a scrotal sperm bank in aplasia of the vas deferens.

Patients with bilateral aplasia of the vas deferens have been considered sterile. In 2 such patients a segment of great saphenous vein, anastomosed to the globus major, was used to accept and store spermatozoa. Aspirations of the venous cap of the patient B at 1 and 4 months revealed numerous sperm with normal morphology and poor motility. At re-exploration of patient A, 4 months after the original venoepididymal procedure, the venous cap was found to be obliterated by scar tissue yet the epididymal tubules remained dilated. A 12-inch segment of the epididymal tubule was compressed between glass slides to obtain sperm in this patient. However, attempted insemination with this sperm was unsuccessful. Our results with the venous cap are disappointing.

Cell Count↗

Operative management of chronic hidradenitis suppurativa of the scrotum and perineum.

Hidradenitis suppurativa of the perineum and scrotum is a progressive disease and, if left untreated, may require a radical operation for its control, including orchiectomy and skin grafting. Five patients with this disease who had failed to respond to antibiotics, and incision and drainage were treated with excision of the involved scrotal and perineal tissue. Healing was promtp and contractures were minimal. Early operative management of this chronic disease is encouraged.

Adolescent↗