Dr. J Andrew Keyoung

All Publications

• Uterine artery anatomy relevant to uterine leiomyomata embolization. Cardiovascular and interventional radiology Gomez-Jorge, J., Keyoung, A., Levy, E. B., Spies, J. B. 2003; 26 (6): 522-7

  Abstract

  To categorize the anatomic variants of uterine arteries, and determine the incidence of menopausal symptoms where the tubo-ovarian branches were seen prior to embolization. Between July 1997 and June 2000, 257 (n = 257) uterine fibroid embolizations were performed at our institution. Arteriograms were retrospectively evaluated. Uterine arteries were classified into groups: type I (the uterine artery as first branch of the inferior gluteal artery), type II (the uterine artery as second or third branch of the inferior gluteal artery), type III (the uterine artery, the inferior gluteal and the superior gluteal arteries arising as a trifurcation), type IV (the uterine artery as first branch of the hypogastric artery), inconclusive, or not studied. Tubo-ovarian branches were recorded if visualized prior to and/or after embolization. Menopausal symptoms were recorded (n = 175 at 3 months, n = 139 at 6 months, n = 98 at 1 year, n = 22 at 2 years) using written questionnaires. Five hundred and fourteen uterine arteries (n = 514) were evaluated. There were 38% classifiable types, 23% inconclusive, and 39% not studied. Classification was as follows: type I, 45%; type II, 6%; type III, 43%; type IV, 6%. Among 256 patients, tubo-ovarian arteries were seen in 36 prior to embolization, but not afterwards. In this group, 25 patients reported transient menopausal symptoms (hot flashes, amenorrhea). Five patients did not report any menopausal symptoms. Six patients did not answer the questionnaires. Type I is the most common type of anatomy, followed by type III. The tubo-ovarian arteries may be visualized prior to and/or after embolization. The embolization was monitored to avoid embolization of the tubo-ovarian branches. Menopausal symptoms were transient all patients when the tubo-ovarian branches were seen prior to embolization.

  View details for DOI 10.1007/s00270-003-2652-7

  View details for PubMedID 15061175

• Idiopathic metaplastic ossification of the breast. Clinical radiology Keyoung, J. A., Zuurbier, R. A., Tsangaris, T. N., Azumi, N. 2001; 56 (9): 775-7

  View details for DOI 10.1053/crad.2001.0789

  View details for PubMedID 11585401

• Intraarterial lidocaine for pain control after uterine artery embolization for leiomyomata. Journal of vascular and interventional radiology : JVIR Keyoung, J. A., Levy, E. B., Roth, A. R., Gomez-Jorge, J., Chang, T. C., Spies, J. B. 2001; 12 (9): 1065-9

  Abstract

  To evaluate the effectiveness of intraarterial lidocaine in controlling pain after uterine artery embolization (UAE).In this double-blind prospective study, patients undergoing UAE received preservative-free 1% lidocaine or saline solution (control) in the uterine arteries before embolization. Postprocedural pain was managed with patient-controlled intravenous morphine. Attempted doses, number of doses received, total morphine dose, and maximum pain numeric rating scale (NRS) score during the postprocedural hospitalization were recorded and compared. Three-month follow-up magnetic resonance (MR) imaging and symptomatic questionnaires were collected and compared.Ten patients received lidocaine and eight patients received placebo. Moderate to severe vasospasm was noted in seven patients after lidocaine injection, whereas no vasospasm was noted in the placebo group (P =.004). Patients in the lidocaine group had lower NRS pain scores than those in the placebo group (P =.012), whereas there was no difference in morphine requirement between treated patients and control subjects. The study was terminated after 18 patients were treated as a result of unexpected vasospasm.Intraarterial 1% lidocaine is associated with moderate to severe vasospasm. Lidocaine significantly lowers subjective pain, but there is no difference in analgesic requirements. The routine use of intraarterial lidocaine is not recommended for pain control until the long-term effects of vasospasm on outcome is known.

  View details for DOI 10.1016/s1051-0443(07)61592-9

  View details for PubMedID 11535769

• Chemotactic responses of Escherichia coli to small jumps of photoreleased L-aspartate. Biophysical journal Jasuja, R., Keyoung, J., Reid, G. P., Trentham, D. R., Khan, S. 1999; 76 (3): 1706-19

  Abstract

  Computer-assisted motion analysis coupled to flash photolysis of caged chemoeffectors provides a means for time-resolved analysis of bacterial chemotaxis. Escherichia coli taxis toward the amino acid attractant L-aspartate is mediated by the Tar receptor. The physiology of this response, as well as Tar structure and biochemistry, has been studied extensively. The beta-2, 6-dinitrobenzyl ester of L-aspartic acid and the 1-(2-nitrophenyl)ethyl ether of 8-hydroxypyrene-1,3,6-tris-sulfonic acid were synthesized. These compounds liberated L-aspartate and the fluorophore 8-hydroxypyrene 1,3,6-tris-sulfonic acid (pyranine) upon irradiation with near-UV light. Photorelease of the fluorophore was used to define the amplitude and temporal stability of the aspartate jumps employed in chemotaxis experiments. The dependence of chemotactic adaptation times on aspartate concentration, determined in mixing experiments, was best fit by two Tar aspartate-binding sites. Signal processing (excitation) times, amplitudes, and adaptive recovery of responses elicited by aspartate jumps producing less than 20% change in receptor occupancy were characterized in photorelease assays. Aspartate concentration jumps in the nanomolar range elicited measurable responses. The response threshold and sensitivity of swimming bacteria matched those of bacteria tethered to glass by a single flagellum. Stimuli of similar magnitude, delivered either by rapid mixing or photorelease, evoked responses of similar strength, as assessed by recovery time measurements. These times remained proportional to change in receptor occupancy close to threshold, irrespective of prior occupancy. Motor excitation responses decayed exponentially with time. Rates of excitation responses near threshold ranged from 2 to 7 s-1. These values are consistent with control of excitation signaling by decay of phosphorylated pools of the response regulator protein, CheY. Excitation response rates increased slightly with stimulus size up to values limited by the instrumentation; the most rapid was measured to be 16 +/- 3 (SE) s-1. This increase may reflect simultaneous activation of CheY dephosphorylation, together with inhibition of its phosphorylation.

  View details for DOI 10.1016/S0006-3495(99)77329-7

  View details for PubMedID 10049350

  View details for PubMedCentralID PMC1300146