Search PubMed⌕ Search

Biomedical subjects

F W Saunders

Publications and source records attributed to F W Saunders.

12 recordsLinked to original sources
PubMed1999

Circadian rhythm of cerebral perfusion pressure and intracranial pressure in head injury.

The aim of the study was to determine if Cerebral Perfusion Pressure (CPP) and Intracranial Pressure (ICP), in patients with head injury, has a circadian rhythm. CPP and ICP data of 13 patients were analysed using the Regressive and Iterative Cosinor methods. The Regressive Cosinor method did not detect a strong 24-hour rhythm. Therefore, the Iterative Cosinor method was used to seek rhythms with period not necessarily equal to 24 hours. Studying consecutive patient days by the Iterative cosinor method showed that rhythm is present but the rhythm period was often not 24 hours. A significant rhythm in the range of 20-30 hours was detected in eight patients for CPP (62%) and in six patients for ICP (46%). To validate the results real and surrogate time series were compared. The clinical implications of rhythmic data analysis are discussed.

Adult↗
PubMed1996

Thermography. Its relation to pathologic characteristics, vascularity, proliferation rate, and survival of patients with invasive ductal carcinoma of the breast.

BACKGROUND: The reason for the thermal abnormality associated with some breast cancers is unclear. We previously reported that a thermographic abnormality is associated with tumor size and lymph node involvement. Despite this association, we were unable to demonstrate an independent association between an abnormal thermogram and survival. METHODS: To expand our previous findings, we assessed patients undergoing liquid crystal (contact) thermography (LCT) to identify a basis for the thermal abnormality and its relationship to survival. We assessed 420 women with invasive ductal carcinoma (IDC) followed for a mean of 6.2 years. In a consecutive series of 181 patients from the overall group, vascularity was assessed using a Doppler ultrasound (US) and microvessel density (MVD) by immunohistochemical staining with Factor VIII-related antigen. The tumor proliferation rate was measured immunohistochemically using Ki-67 monoclonal antibody. RESULTS: An abnormal thermogram was found in 18.6% of patients with IDC. A significant association was demonstrated between an abnormal LCT and age, stage, lymph nodal status, size, grade, and estrogen receptor status. We found no association between a LCT abnormality and MVD or proliferation rate. There was a significant relationship with US-demonstrated vascularity. In multivariate analysis, we found that LCT abnormality was not an independent prognostic variable for either overall or disease free survival. CONCLUSIONS: An abnormal thermogram is associated with large tumor size, high grade, and lymph node positivity but not proliferation rate or MVD. It also may be associated with relatively large regional vessels that can be identified by US. However, thermography is not an independent prognostic indicator.

Age Factors↗
PubMed1990

Topical glyceryltrinitrate causes measurable penile arterial dilation in impotent men.

The current understanding of the intracavernous changes that cause or accompany penile erections has encouraged the use of vasodilators as therapy for erectile dysfunction. An established vasodilator, glyceryltrinitrate, was selected for in vivo study because of its rapid transdermal absorption. Color coded duplex ultrasound was used to assess penile vascular response. In a large group of men with erectile dysfunction significant dilation was noted in response to a small amount of nitroglycerine paste applied to the penis. There is a measurable vasodilatory response that can be induced by synthetic nitrates in penile tissue in impotent men.

Blood Flow Velocity↗
PubMed1988

Intracranial blood velocity in head injury. A transcranial ultrasound Doppler study.

We report our experience monitoring head-injured patients by means of transcranial Doppler sonography. Cerebral velocity measurements and waveforms change in a consistent pattern with the existence of intracranial pressure, and it is possible to discriminate low versus high flow states. The technique, in contrast to cerebral blood flow measurement, is reliable, atraumatic, and repeatable so that diagnostic assessments can be made and the patient can be followed for therapeutic efficacy.

Adolescent↗
PubMed1987

Spinal artery aneurysm.

A case of a spinal artery aneurysm is presented and the relevant literature is reviewed. The pathology of this aneurysm differed from that of standard intracranial aneurysms. The coexistence of a spinal aneurysm and fibromuscular hyperplasia has not been previously reported.

Aneurysm↗
PubMed1986

Diltiazem: possible hematologic complications.

Calcium blockers are being investigated for a potential role in the prevention and treatment of cerebral vasospasm. They have been found to inhibit platelet function both with in vivo and with in vitro experiments. Clinical evidence of abnormal platelet function is sparse, however. We are presenting three patients who developed increased bleeding times that reverted to normal when the diltiazem was discontinued. This may lead to serious consequences in the presence of an unsecured aneurysm and for patients facing major intracranial surgery.

Adult↗
PubMed1986

Diltiazem: dose it affect vasospasm?

Calcium antagonists are being investigated for their role in preventing or ameliorating the vasospasm associated with subarachnoid hemorrhage. We have done a phase I and phase II type trial of diltiazem. No effect on spasm was documented. A tendency to increase the bleeding time was noted, but no detrimental clinical effect occurred. The rebleed rate was not changed. It appears that further study of diltiazem through a proper randomized study would not be cost- or time-effective.

Benzazepines↗
PubMed1985

The carotid siphon: a scanning electron microscope assessment of its embolic potential.

The role of the carotid siphon as a source of embolic material has had limited morphological or clinical study. The morphologic data available suggests that the siphon plays only a small role in embolic cerebrovascular disease. Clinical studies, however, suggest that it has a significant ischemic potential. To clarify this apparent discrepancy, we have designed a scanning electron microscope study of the carotid siphon. Eighty percent of the specimens from the carotid bifurcation and 30% of the siphon specimens showed evidence of damaged endothelium with attached red cell and platelet debris. The embolic potential of the siphon is estimated to be between 1/3 to 1/2 that of the carotid bifurcation. This supports the most recent clinical studies.

Arteriosclerosis↗
PubMed1980

Scar prevention in peripheral nerve surgery.

Constriction of a peripheral nerve may precipitate a primary problem of prevent recovery from a pre-existing one. Any surgical technique to minimize subsequent constrictive scar formation would be advantageous. In this study, using rat femoral nerves, various modes of protection were evaluated. Wrapping the nerve with free fat seemed to offer the best prophylaxis.

Adipose Tissue↗
PubMed1976

Herpes simplex encephalitis: treatment with surgical decompression and cytosine arabinoside.

Herpes simplex encephalitis in a 21-year-old man presented as a flu-like illness, followed by inappropriate behaviour, drowsiness and focal neurologic signs. Investigations indicated a lesion in the right temporal lobe. The diagnosis was confirmed by isolation of the virus from a cerebral biopsy. Pronounced clinical improvement was noted when cytosine arabinoside therapy was started in the postoperative period. This report supports the observation by some authors that cytosine arabinoside may be of value in the treatment of herpes simplex encephalitis.

Adult↗