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D E Haines

Publications and source records attributed to D E Haines.

At least 55 records · Page 3Linked to original sources
PubMed1998

Anatomy of the shaken baby syndrome.

Shaken baby syndrome refers to the constellation of nonaccidental injuries occurring in infants and young children as a consequence of violent shaking. The typical victim of shaken baby syndrome is a male infant younger than six months of age who is alone with the perpetrator at the time of injury. Occurrence of the syndrome is unrelated to race, gender, socioeconomic status, or education. The characteristic injuries observed in shaken baby syndrome include subdural hemorrhages, retinal hemorrhages, and fractures of the ribs or long bones. Although each of these injuries may result from violent shaking of the victim, the most severe brain injuries result from the addition of a forceful impact of the infant's or child's head against a firm surface. The unique anatomic features of the infant's head and skeletal system, which account for the type and pattern of injuries observed in shaken baby syndrome, are emphasized in this article.

Battered Child Syndrome↗
PubMed1998

A.J. Ladman: managing editor of The Anatomical Record, 1968-1998.

In the period 1906-1998, The Anatomical Record has had only six managing editors. One of these individuals, A.J. Ladman, served in this capacity for 30 years, almost a full third of the history of this journal up to 1998. Ladman received his Ph.D. degree from Indiana University in 1952, was at Harvard for 9 years (1952-1961) and at the University of Tennessee from 1961-1964. He became professor and chairman of the Department of Anatomy at the University of New Mexico School of Medicine in 1964. In April 1968, Ladman was appointed managing editor of The Anatomical Record by the American Association of Anatomists (AAA). He brought energy and innovative ideas to the journal and would apply those in the changes he instituted over the years of his tenure. In April 1998, after 30 years of exemplary service to this journal and to the AAA, Ladman passed the responsibility on to Roger Markwald. During his career, and in addition to his editor's work, he conducted research on an impressively wide range of topics, served as an elected officer in several professional organizations, and was founding chair of anatomy at New Mexico. He went to Hahnemann in 1981, served as Dean of the School of Allied Health Professions (1981-1986), and is currently adjunct professor of neurobiology and anatomy. The AAA expresses its sincere appreciation to A.J. Ladman for his excellent stewardship of The Anatominal Reord.

Anatomy↗
PubMed1998

The child as a projectile.

Unintentional injury is the leading cause of death in children under the age of fourteen. The majority of these injuries/deaths occur when the child becomes airborne during an accident. The most common mechanisms by which children become airborne are motor vehicle collisions, bicycling accidents, and falls. A head injury is seen in a significant number of children in this setting. This includes injury to the scalp, skull, coverings of the brain, or the brain itself. These injuries are the most common cause of death in children resulting from unintentional injury. Other typical injuries include external bruises and abrasions, extremity fractures, and bruising or bleeding of internal organs. We propose to name this constellation of injuries the projectile child syndrome. This refers to those injuries occurring in infants and children as a result of becoming airborne during the events of an accident. The pattern of injuries seen as related to the anatomy of the child is stressed. A review of the impact to society and guidelines for prevention are presented.

Accidental Falls↗
PubMed1998

Efficacy of multiple ring and coil electrode radiofrequency ablation catheters for the creation of long linear lesions in the atria.

Atrial fibrillation is an arrhythmia that may potentially be treated by creating long linear lesions in the atria to create lines of electrical conduction block. While this has been performed with success with open-heart surgery, it has been proposed that a less invasive catheter-based approach could achieve similar success. Radiofrequency energy catheter ablation was performed in vivo with two novel electrode catheters. Each was an expanding loop design: one with 3 mm ring electrodes; and one with 12.5 mm coil electrodes. Power delivery was controlled automatically with temperature (70 degrees C target) feedback from thermistors embedded in each electrode. A total of 39 lines of ablation were created in the atria of 11 normal dogs. The coil electrodes were more effective in creating lesions than the ring electrodes with a similar prevalence of transmurality (89% vs. 85%) but a higher prevalence of continuous transmurality (35% vs. 5%). Sequential electrode energy delivery was better than simultaneous multipolar delivery due to varying efficiencies of tissue heating. Inadequate heating was observed in 47% of simultaneous versus 1% of sequential multipolar deliveries, and excessive heating in 6% versus 1% of cases, respectively. It is feasible to create linear atrial lesions with an expanding loop electrode catheter. Catheters with coil electrodes are more effective than those with ring electrodes. In order to avoid coagulum formation and inefficient heating, sequential electrode energy delivery is preferable to multipolar delivery.

Animals↗
PubMed1997

Nonuniform heating during radiofrequency catheter ablation with long electrodes: monitoring the edge effect.

BACKGROUND: Long, narrow electrodes are being considered for radiofrequency ablation of atrial fibrillation; however, preliminary work revealed coagulum formation on the electrodes and lack of lesion continuity. This may be due to the "edge effect," which concentrates radiated energy at sharp geometric gradients. It is proposed that temperature sensors at electrode edges are preferable to a single centered sensor for temperature feedback and monitoring of long electrode geometries. METHODS AND RESULTS: A finite element model was used to predict the heating properties of new long electrode geometries. Sixteen dogs with atrial fibrillation underwent left and right atrial ablation using catheters with multiple 12.5-mm coil electrodes. Electrodes with a single thermistor were compared with electrodes with dual thermocouples placed at opposite ends and on opposing sides of the electrode. Power, temperature, and impedance were recorded for all lesions, and coagulum adhesion and magnitude were noted in a subset of lesions. Finite element analysis shows uneven heating, with the main heating concentrated at the electrode edges and a propensity toward temperatures >100 degrees C with single-thermistor feedback control. Ablations with dual thermocouple electrodes achieved higher measured temperatures at lower power levels than those that used single-thermistor electrodes. Impedance rises and coagulum adherence occurred less frequently with dual thermocouple electrodes than with single, centered thermistor electrodes (176 of 395 versus 9 of 425 lesions; P<.0001; 46 of 98 versus 7 of 150 lesions; P<.0001, respectively). CONCLUSIONS: Maximum heating from radiofrequency energy occurs at the electrode edges, particularly with long electrodes. The safety of temperature-feedback atrial ablation with these electrodes is significantly improved by monitoring temperatures at the edges.

Animals↗
PubMed1997

Entrainment mapping in patients with sustained atrioventricular nodal reentrant tachycardia: insights into the sites of conduction slowing in the slow atrioventricular nodal pathway.

The inferoposterior region of the triangle of Koch is hypothesized to be the location of the atrial insertion of the slow atrioventricular (AV) nodal pathway. However, the actual site of conduction slowing in the slow AV nodal pathway is unknown. Entrainment mapping during AV nodal reentry can localize the reentrant pathway as follows: the AH interval measured from the mapping catheter = A'H (where A' is the exit site of the reentrant circuit) minus A'A (the conduction time from A' to the site of mapping); the SH interval during entrainment = SA' (the conduction time from stimulus into the reentry circuit) plus A'H. Thus, in all cases, the SH interval should be greater than or equal to the AH interval, and the deltaAH-SH should increase as distance and conduction time (SA' and A'A) from the reentry circuit increases. Fourteen patients with typical AV nodal reentry (cycle length 346 +/- 62 ms) and 1 with fast-slow (cycle length 430 ms) underwent activation and entrainment mapping from 8 to 12 sites in the triangle of Koch and coronary sinus. Pacing was performed at 2 to 3 mA above threshold, at a cycle length 10 ms shorter than tachycardia. A mapping site was defined as being in close proximity to the circuit if the deltaAH-SH was within 120% of the shortest 20th percentile deltaAH-SH value from all measured sites. In the 14 typical cases, 45 of 83 sites (54%) in the anatomic slow pathway region fulfilled criteria for close proximity to the reentry circuit compared with 13 of 50 sites (26%) outside of this region (p = 0.005). For these patients, the shortest SH interval measured from any entrainment site was 294 +/- 58 ms (89 +/- 10% of tachycardia cycle length, range 70% to 119%), indicating that the site of slow conduction in the slow pathway during AV nodal reentrant tachycardia was distal to all mapped sites. Thus, during typical AV nodal reentry, the "slow" pathway does not conduct slowly, and its insertion is located at or within the inferoposterior or midseptal regions in most cases.

Adult↗
PubMed1997

The cerebellar-hypothalamic axis: basic circuits and clinical observations.

Experimental studies on a variety of mammals, including primates, have revealed direct and reciprocal connections between the hypothalamus and the cerebellum. Although widespread areas of the hypothalamus project to cerebellum, axons arise primarily from cells in the lateral, posterior, and dorsal hypothalamic areas; the supramammillary, tuberomammillary, and lateral mammillary nuclei; the dorsomedial and ventromedial nuclei; and the periventricular zone. Available evidence suggests that hypothalamocerebellar cortical fibers may terminate in relation to neurons in all layers of the cerebellar cortex. Cerebellohypothalamic axons arise from neurons of all four cerebellar nuclei, pass through the superior cerebellar peduncle, cross in its decussation, and enter the hypothalamus. Some axons recross the midline in caudal areas of the hypothalamus. These fibers terminate primarily in lateral, posterior, and dorsal hypothalamic areas and in the dorsomedial and paraventricular nuclei. Evidence of a cerebellar influence on the visceromotor system is presented in two patients with vascular lesions: one with a small defect in the medial cerebellar nucleus and the other with a larger area of damage involving primarily the globose and emboliform nuclei. Both patients exhibited an abnormal visceromotor response. The second, especially, showed abnormal visceromotor activity concurrent with tremor induced by voluntary movement. These experimental and clinical data suggest that the cerebellum is actively involved in the regulation of visceromotor functions.

Aged↗
PubMed1996

Atrial rhythm after atrioventricular junctional ablation.

Atrioventricular (AV) junctional ablation followed by pacemaker implantation is an established treatment for patients with refractory paroxysmal atrial arrhythmias. The stability of the underlying atrial rhythm after AV junctional ablation is unknown. This study evaluates the atrial rhythm after AV junctional ablation in 49 patients with medically refractory atrial arrhythmias. The group included 25 men and 24 women, of whom 36 had known structural heart disease. Paroxysmal atrial fibrillation was the primary rhythm disturbance in 41 patients, whereas 8 manifested either atrial tachycardias or atrial flutter. All patients had failed therapy with > or = 1 antiarrhythmic drug. Chronic pacing modes were DDIR or DDDR, with mode switching in 15 patients and VVIR in 34 patients. After AV junctional ablation, chronic antiarrhythmic drug therapy was prescribed in only 4 patients (8%). Routine electrocardiograms (ECGs; 6.5 +/- 6.1/patient) during long-term follow-up (18.6 +/- 15.6 months) showed that 7 patients (14%) had an atrial arrhythmia detected on all ECGs, 30 patients (61%) had sinus or atrial-paced rhythms on all recordings, and 12 patients (25%) had both atrial arrhythmias and sinus rhythm documented. Sinus or an atrial-paced rhythm was present on the last available ECG in 33 of 49 patients (67%). Pacing mode was not a predictor of continued sinus rhythm. In conclusion, most patients with a history of paroxysmal atrial tachyarrhythmias will not convert to chronic atrial arrhythmias after AV junctional ablation, even in the absence of antiarrhythmic drug therapy. Use of dual-chamber pacing modes will allow maintenance of at least intermittent atrial function in these patients.

Aged↗
PubMed1996

Sensing lead-related complications in patients with transvenous implantable cardioverter-defibrillators.

The widespread use of the redesigned Endotak lead (CPI, St. Paul, Minnesota), which combines transvenous pacing, sensing, and defibrillation on a single transvenous lead in patients receiving transvenous implantable cardioverter-defibrillators (ICDs), has reduced morbidity and shortened length of hospital stay after ICD implantation. We describe the incidence and management of Endotak sensing lead-related failures in a series of 348 consecutive patients from 4 institutions who underwent implantation between 1990 and 1995. We retrospectively reviewed the databases for patients receiving an ICD with an Endotak lead for the incidence of lead-related sensing abnormalities. Ten patients (2.8%) with lead-related sensing abnormalities were detected at a mean of 15 +/- 11 months after ICD implantation. Sensing abnormalities were detected in 6 patients after they received inappropriate shocks. Noise or oversensing was noted in 7 patients from interrogation of the devices' data logs. Eight patients had a new transvenous sensing lead placed, 1 patient had a new Endotak lead placed, and 1 had a chronic pacemaker sensing lead converted to function as a sensing lead. No further sensing problems were noted in 8 of 10 patients during a mean follow-up of 14 +/- 8 months. The site of the sensing lead failure was localized to the subrectus pocket in 5 patients and to the clavicle-first rib area in 3 patients; it was undetermined and presumed to be in the clavicle-first rib area in the other 2 patients. One patient had late failure of the defibrillation lead. We conclude that Endotak sensing lead failure does not require insertion of a new Endotak lead, but can be managed with close follow-up and insertion of a new transvenous sensing lead. Endotak lead fractures are frequently localized to the ICD pocket.

Aged↗
PubMed1996

Effects of dispersive electrode position and surface area on electrical parameters and temperature during radiofrequency catheter ablation.

Positioning of the dispersive electrode has no significant effect during radiofrequency ablation. Doubling the surface are of the dispersive electrode results in a lower impedance, higher current delivery, and increased tip temperatures, particularly if the baseline impedance is >100 ohms. These findings may have important implications for optimizing radiofrequency energy delivery using currently available radiofrequency generators.

Cardiac Catheterization↗
PubMed1996

Expanding cyst of the septum pellucidum. Case report.

Expanding cysts of the septum pellucidum, although rare, may be a cause of significant neurological dysfunction. Most become symptomatic as a result of obstruction of the interventricular foramina and produce headaches, papilledema, emesis, and loss of consciousness. Behavioral, autonomic, and sensorimotor symptoms occur when an expanding cyst impinges on the structures of the hypothalamoseptal triangle or impairs the deep cerebral venous drainage. Neuroophthalmological symptoms may develop as a consequence of hydrocephalus or direct compression of visual structures. The authors describe the case of a young boy with an expanding septum pellucidum cyst who presented with a sudden, severe headache and loss of consciousness. In addition, he had a history of hyperactivity and progressively declining school performance. All symptoms resolved following decompression of the cyst. Seventeen cases from the literature are reviewed. The pathophysiological mechanisms underlying the development of symptoms secondary to expanding septum pellucidum cysts are outlined, and the related clinical neuroanatomy is described. A model is proposed for the natural history of expanding septum pellucidum cysts that provides a rational basis for understanding their clinical behavior and response to intervention. In most cases, fenestration or shunting will relieve the obstructive hydrocephalus and mass effect caused by the cyst and will produce rapid symptomatic improvement.

Brain Diseases↗