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T Buckenham

Publications and source records attributed to T Buckenham.

26 records · Page 2Linked to original sources
PubMed1993

Microscopic air embolism during cerebral angiography and strategies for its avoidance.

Cerebral angiography is associated with a risk of neurological complications and air embolism may contribute towards this risk. To test this hypothesis, transcranial doppler ultrasonography was used to monitor the presence of air emboli in the middle cerebral arteries of 7 patients undergoing cerebral angiography. Doppler signals consistent with numerous air emboli were noted during each injection of radiographic contrast. This phenomenon was studied further in sheep. Radiographic contrast medium was injected into the carotid artery while a major carotid branch was insonated transorbitally. Embolic signals similar to those seen in patients were noted. Air was introduced at two points. First, at the time of drawing up the contrast into the syringe, especially with more viscous media. Standing the media before injection resulted in a highly significant reduction of air embolism, reducing the total mean duration of emboli from 1.32 (SD 0.60) s after immediate injection to 0.04 (0.05) s after ten minutes standing for iohexol 340 mg/mL (p < 0.001). Second, air was introduced at the time of injection, possibly by the formation of cavitation bubbles under pressure. This occurred most prominently with the less viscous contrast media and with saline, and was significantly reduced by slow injection (mean duration of emboli for saline 2.85 [2.43] s with fast injection compared with 0.32 [0.37] s with slow injection, p = 0.004). Air embolism may contribute towards neurological dysfunction after angiography. Measures should be taken to reduce this by allowing contrast media to stand prior to injection, and by flushing catheters with saline injected slowly.

Adult↗
PubMed1993

Interventional sialography using digital imaging.

We review our results in treating 5 patients with parotid duct pathology (3 stenoses, 2 calculi), using digital subtraction imaging for sialography, and standard interventional techniques using balloon catheters. Good technical results were achieved in all 5 patients. We describe our techniques and how they were modified to overcome various difficulties.

Catheterization↗
PubMed1992

Thrombolysis of the occluded prosthetic graft with tissue-type plasminogen activator--technique, results and problems in 23 patients.

Over a 12 month period all patients but one presenting to our hospital with occluded prosthetic grafts were treated by thrombolysis using local pulsed administration of tissue-type plasminogen activator (t-PA). There were 30 interventions in 23 patients but in one patient no thrombolytic was given after aspiration of pus from the graft. Thrombolysis was attempted in the remaining 29 procedures. 22/29 (76%) of these procedures were performed by direct puncture and catheterization of the occluded graft and in a further six (21%) access was from a non-occluded femoral artery or graft. In one case the graft was accessed surgically. Supplementary angioplasties were performed in 15 cases (52%). Complications requiring surgery occurred in four (14%) with a further seven minor complications. There were no deaths. A lower rate of complications occurred in the grafts entered by direct puncture. Thrombolysis was achieved in all but one case taking an average of only 2.5 h but was only maintained beyond the end of the procedure in 21/29 (72%). An underlying cause for occlusion was identified and treated where possible, e.g. haematological or clotting abnormalities or inflow or outflow stenoses. There was a high rate of reocclusion but with repeat procedures when necessary patency was maintained in 10/22 patients (45%) on follow-up at 1 to 12 months. The best results were obtained with lysis of occluded femoro-femoral crossover grafts.

Aged↗
PubMed1991

Antenatal ultrasonography in Dunedin: one year's data.

Two thousand and forty-five pregnancies were registered during one calendar year, at the two hospitals in Dunedin. One thousand five hundred and ninety-four liveborn infants and 15 stillborn infants resulted from 1585 pregnancies. Of this group of pregnant women, 74% had one or more ultrasonographic studies (mean number of scans = 1.5). Of the 1609 infants delivered, 0.4% had a major anomaly of the central nervous system, and 0.7% had hydroenphrosis. Four hundred and sixty pregnancies resulted in spontaneous or therapeutic abortion. Ten point nine percent of those women undergoing therapeutic abortion had ultrasonographic studies. It is apparent from this retrospective audit, that antenatal ultrasonography has become almost routine in those women carrying an infant to term. The relative rarity of fetal anomalies is similar to other, larger, series.

Abortion, Spontaneous↗