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Biomedical subjects

R D Henderson

Publications and source records attributed to R D Henderson.

At least 37 records · Page 2Linked to original sources
PubMed2000

Angiographically defined collateral circulation and risk of stroke in patients with severe carotid artery stenosis. North American Symptomatic Carotid Endarterectomy Trial (NASCET) Group.

BACKGROUND AND PURPOSE: Blood supply through collateral pathways improves regional cerebral blood flow and may protect against ischemic events. The effect of collaterals on the risk of stroke and transient ischemic attack (TIA), in the presence of angiographic severe internal carotid artery (ICA) stenosis, was assessed. METHODS: Angiographic collateral filling through anterior communicating and posterior communicating arteries and retrograde filling through ophthalmic arteries were determined in all patients at entry into the North American Symptomatic Carotid Endarterectomy Trial. Kaplan-Meier event-free survival analyses were performed on 339 medically treated and 342 surgically treated patients. RESULTS: The presence of collaterals supplying the symptomatic ICA increased with severity of stenosis. Two-year risk of hemispheric stroke in medically treated patients with severe ICA stenosis was reduced in the presence of collaterals: 27.8% to 11.3% (P=0.005). Similar reductions were observed for hemispheric TIA (36.1% versus 19.1%; P=0.008) and disabling or fatal strokes (13.3% versus 6.3%; P=0.11). For surgically treated patients, the perioperative risk of hemispheric stroke was 1.1% in the presence of collaterals versus 4. 9% when absent. The 2-year stroke risks for surgical patients with and without collaterals were 5.9% versus 8.4%, respectively. Neither comparison in the surgical group was statistically significant. The observed reductions were independent of the degree of ICA stenosis and other vascular risk factors. CONCLUSIONS: Collaterals are associated with a lower risk of hemispheric stroke and TIA, both long term and perioperatively. Angiographic identification of collaterals assists in identifying patients with severe ICA stenosis at lower risk of stroke and TIA.

Aged↗
PubMed2000

Effect of contralateral carotid artery stenosis on carotid ultrasound velocity measurements.

BACKGROUND AND PURPOSE: Carotid ultrasonography is being increasingly performed as the sole investigation to assess internal carotid artery (ICA) stenosis. A potential source of error in using ultrasound peak systolic velocity (PSV) measurements is that the redistribution of blood flow due to severe stenosis in a contralateral carotid artery may lead to artificially elevated values. METHODS: Ultrasonography was performed before and after carotid endarterectomy in symptomatic patients who participated in the North American Symptomatic Carotid Endarterectomy Trial (NASCET). The mean change in PSV in the unoperated artery was assessed across all degrees of angiographically defined stenosis. A simple theoretical resistance model of the cerebral circulation was also derived. RESULTS: Complete bilateral ultrasound examinations were performed within 90 days of the initial scan in 386 patients. In the presence of a contralateral severe (70% to 99%) ICA stenosis, the PSV in the unoperated artery was artificially elevated by a mean of 84 cm/s (P:=0.03; 95% CI, 10 to 159 cm/s). The mean elevation was less pronounced for lesser degrees of stenosis (11 to 21 cm/s). Small elevations (3 to 12 cm/s) were observed when the contralateral artery had <70% stenosis. The patterns of observed results were congruent with those from the theoretical model. CONCLUSIONS: The present study showed that a severely stenosed contralateral ICA can artificially elevate ultrasound PSV. Since the effect was greatest when bilaterally severe stenoses were present, caution must be exercised when assessing the degree of ICA stenosis on the basis of ultrasonography PSV measurements alone.

Aged↗
PubMed2000

The deceptive nature of root coverage results.

BACKGROUND: The purposes of this article are to: 1) propose a new method of reporting root coverage data; 2) compare existing root coverage techniques using the proposed data analysis method; and 3) discuss additional refinements to root coverage data analysis. Past studies have equated percent defect coverage with root coverage. This gives deceptive information about the magnitude of the residual recession defect. Defect coverage of 67% could actually amount to 92% root coverage. METHODS: The use of mean root lengths will permit the determination of true root coverage data. This should be reported in addition to defect coverage data. Also including frequency data will provide a better assessment of the predictability of the surgical techniques. RESULTS: A comparison table of root coverage studies demonstrates that the connective tissue graft is the most effective and predictable method that has been tested. CONCLUSIONS: Further refinements to data analysis may help researchers identify the determinants of predictable root coverage.

Connective Tissue↗
PubMed1999

Root coverage using Alloderm acellular dermal graft material.

This report describes a surgical technique for root coverage using an acellular dermal graft material and a coronally positioned flap. Video clips of a root coverage surgery are included using the graft material to cover multiple teeth in the same quadrant. Three additional completed cases are presented in which a mean root coverage of 97% was achieved, resulting in 100% coverage on 9 of 11 teeth. The results from this case series conform with the available evidence on the use of acellular dermal graft material in root coverage procedures.

Adult↗
PubMed1998

The Arousability Predisposition Scale: validity and determinants of between-subject variability.

Norms for the Arousability Predisposition Scale (APS; S. Coren, 1990) obtained from an Australian university sample are presented. The construct tapped by the APS is reviewed, with state and trait anxiety, sex, and age examined as possible determinants of individual arousability predisposition. Sex differences were found on trait anxiety and APS measures--women scored higher than men on those respective measures. Regression analysis revealed that trait anxiety accounted for a large proportion of variance on the APS, whereas sex accounted for a small, but statistically significant, proportion of variance. It is suggested that the APS taps a component of trait anxiety. Further research is called for to validate the APS as a measure of physiological arousability and as a useful psychophysical tool.

Adolescent↗
PubMed1998

Goodpasture's syndrome associated with multiple sclerosis.

Multiple sclerosis (MS) has been reported to occur in association with other autoimmune diseases. Here we report the case of a woman with primary progressive MS who developed and died of Goodpasture's syndrome associated with anti-glomerular basement membrane antibodies. Of interest she had the human leukocyte antigen haplotype (DRB1*1501-DQA1*0102-DQB1*0602) most frequently associated with these two diseases; however, it is likely that other genes, particularly those involved with immunoregulation, also contributed to her susceptibility to these diseases. The association of MS and autoimmune renal disease may be more common than currently recognized.

Adult↗
PubMed1990

Surgical management of 100 consecutive esophageal strictures.

We report our experience with 100 consecutive patients with reflux-induced esophageal structure managed surgically. Preoperative dilatation, total fundoplication gastroplasty, and postoperative dilatation were used in 98 patients. Only two required resection of the esophageal structure. We have identified preoperative factors that adversely affect the results. These include scleroderma; previous operation, either esophageal or gastric, and the severity of the esophageal stricture. Results of nonresectional operations are excellent in uncomplicated cases or with the addition of only one complicating factor. The more complicating factors, the worse the results. Those patients with three preoperative complicating factors do poorly and may benefit from esophageal resection. We conclude that results obtained from this conservative nonresectional management program justify continuance of the use of total fundoplication gastroplasty with preoperative and postoperative dilatation in the management of such patients.

Adult↗
PubMed1989

Closure of chronic postpneumonectomy bronchopleural fistula using the transsternal transpericardial approach.

Thirteen patients with postpneumonectomy bronchopleural fistula occurring 4 months to 10 years after the initial operation have been treated with a transsternal transpericardial approach after the associated empyema had been treated by either tube thoracostomy or open-window thoracostomy. In 10 patients, there were contraindications to using an ipsilateral transthoracic approach. In 10 of the 13 patients, the procedure was successful. Three fistulas recurred; two were quite small, one of them closing spontaneously within 6 months. There were no deaths or clinically significant morbidity related to the transsternal approach. We have found this technique to be most applicable in those patients in whom other procedures have failed to resolve the problem. The technique is relatively simple and safe.

Adult↗
PubMed1989

Myotomy for reflux-induced cricopharyngeal dysphagia. Five-year review.

This report describes 25 patients with reflux-induced cricopharyngeal dysphagia ultimately requiring surgical management. Eighteen patients underwent cricopharyngeal myotomy alone and seven patients required cricopharyngeal myotomy after an antireflux operation failed to correct this symptom. Cricopharyngeal incoordination was demonstrated at manometry in over 90% of patients. Treatment included cricopharyngeal myotomy, which was extended proximally to the pharynx and distally to the intrathoracic esophagus. Results were excellent to satisfactory in 24 of 25 patients. Pathologic examination of the cricopharyngeal muscle demonstrated a wide variety of myopathic degenerative changes. We stress that cricopharyngeal myotomy may be performed even in the presence of reflux without fear of subsequent aspiration.

Adult↗
PubMed1989

The total fundoplication gastroplasty: surgical procedure and radiologic appearance.

The total fundoplication gastroplasty (TFG) consists of a combination of an esophagus-lengthening Collis gastroplasty and suturing of the gastric fundus to the esophagus and neo-esophagus to produce a stable intra-abdominal segment together with a complete Nissen fundoplication tailored in length to control reflux and avoid overcompetence. We studied 50 patients at least three months after TFG with an upper gastrointestinal examination and a tube esophagogram. Tube esophagography enhances distension of the esophagus and esophagogastric junction and eliminates the barium pool often seen in the distal esophagus in double-contrast esophagography. With this technique we were better able to understand the radiologic anatomy of the esophagogastric junction following TFG. Tube esophagography provided additional radiologic information in the five patients (10%) with preoperative peptic strictures of the esophagus. We describe the surgical and radiologic anatomy of the TFG, the technique of postoperative radiographic examination, and the postoperative problems we have encountered.

Adolescent↗
PubMed1988

Review of the surgical management of recurrent hiatal hernia: 5-year follow-up.

Symptoms in patients with hiatal hernia often respond to treatment consisting of diet and medication. Operative procedures, designed to control gastroesophageal reflux and avoid surgically induced problems, are reserved for those with intractable symptoms. When these operative procedures fail, reoperation may be necessary. The reoperative procedure is often technically complex because of esophageal and gastric scar fixation. The authors reviewed the surgical management of recurrent hiatal hernia in 168 patients followed up to 5 years or more; 43 of them had undergone gastric surgery previously.Radiologically, 97% patients studied (142 of 146) had no evidence of anatomic recurrence or reflux post operatively. Manometric studies postoperatively in 114 patients showed that the mean tone of the high pressure zone was within the normal range and lower esophageal disordered motor activity was decreased by 34.5% from the preoperative level. Symptoms of recurrent hiatal hernia were abolished by operation in 88% of the patients; only 4.8% had serious or recurrent symptoms.

Adult↗
PubMed1987

Extended esophageal myotomy and short total fundoplication hernia repair in diffuse esophageal spasm: five-year review in 34 patients.

Diffuse esophageal spasm (DES) is a rare disease, and its surgical management is controversial. There are seven major reported series totaling 148 patients and six operative variations depending on the extent of myotomy and whether or not a hernia repair should be added. There are no five-year follow-up reports. In the present study of 34 patients followed for at least five years, all had a myotomy from the apex of the chest through the high-pressure zone and all had a total fundoplication hernia repair, 16 with gastroplasty and 16 with a standard Nissen fundoplication. The length of the completion fundoplication is reduced to less than 0.5 cm to avoid problems of overcompetence. There were no operative deaths. Follow-up is 100% by clinical history, 82.4% by radiology, and 61.8% by manometry. Radiological follow-up showed no recurrence or reflux, although 1 patient had esophageal mucus retention. Thirty patients (88.2%) are eating normally without dysphagia or spontaneous pain. Two patients (5.9%) have mild dysphagia, and 1 of them also has mild spontaneous pain. One patient has major residual dysphagia, which is being treated conservatively, and 1 has required colon interposition. Good-quality results have been achieved in 94% of patients now followed 5 to 10.7 years.

Esophageal Diseases↗
PubMed1987

Esophageal motor disorders.

Primary esophageal motor disorders are rare, but they respond well to surgery if they are accurately diagnosed and if treatment carefully follows the fundamental principles of management. In the lower esophagus the most important primary disorders are achalasia, diffuse esophageal spasm, and scleroderma. Upper esophageal primary disorders are mostly rare; however, problems of age and neurologic diseases are a significant source of debility, making their management important. Details of investigation and management have been outlined in this article.

Age Factors↗
PubMed1987

A comparative assessment of tube esophagography with double-contrast esophagography in the detection of reflux esophagitis.

We undertook a prospective study comparing the sensitivities of double-contrast and tube esophagography in 34 patients with gastroesophageal reflux and compared our findings with those at endoscopy. Neither test detected changes accurately in mild inflammation; however, they both became more sensitive as the severity of esophagitis increased. The sensitivity of both tests increased from 0% in grade 2 to 86% in grade 4 esophagitis. The tube esophagogram demonstrated inflammatory changes better than the double-contrast esophagogram in only 18% of the 34 patients, all with grade 3 or 4 esophagitis, despite the elimination of the barium pool in the distal esophagus and improved distension of the esophagogastric junction. Endoscopy is still the most reliable means of diagnosing and grading esophagitis.

Adolescent↗
PubMed1986

Surgical management of the failed gastroplasty.

Gastroplasty has been used in surgical management of reflux for 25 years. The creation of a gastric tube before fundoplication complicates further corrective procedures should the original operation fail. Experience has been gained with 51 patients, 34 having partial fundoplication gastroplasty and 17 having total fundoplication, who have had major persistent or recurrent symptoms. All were evaluated by history, radiology, endoscopy, manometry with pH, and acid perfusion testing before surgical management. The patients undergoing partial fundoplication gastroplasty had heartburn (85.3%), reflux (70.6%), and dysphagia (94.1%). Radiologic recurrence was present in 26.5%, endoscopic incompetence in 94.1%, and a stricture in 26.5%. The patients who had a total fundoplication gastroplasty had heartburn (52.9%), reflux (29.4%), and dysphagia (82.4%). Radiologic recurrence was present in 29.4%, endoscopic incompetence in 35.3%, and a stricture in 5.9%. On average, these patients had had 2.3 prior operations (range one to five operations). The dominant cause of failure (in the absence of anatomic recurrence) with partial fundoplication gastroplasty was continued or recurrent reflux and with total fundoplication gastroplasty, too tight or too long a fundoplication. All patients had a thoracoabdominal revision total fundoplication gastroplasty and a 1 cm completion fundoplication. Pyloromyotomy was added if not previously performed. There were no deaths or major morbidity. Follow-up in 51 patients averages 4.2 years (range 0.3 to 8.8 years). None has radiologic recurrence, one has minor reflux, one a traumatic diverticulum, and one has moderate esophageal obstruction. Of these patients, 82.4% are asymptomatic, 13.7% have minor symptoms, and 3.9% (two patients) have significant residual symptoms. This conservative surgical approach avoids the higher mortality of resection with interposition and provides satisfactory results.

Adolescent↗
PubMed1985

Total fundoplication gastroplasty (Nissen gastroplasty): five-year review.

Gastroplasty was introduced by Collis in 1961 and has undergone several modifications. The combination of total fundoplication with gastroplasty was reported in 1977 and referred to as total fundoplication gastroplasty; however, the term Nissen gastroplasty also is commonly used. This article is an extension of the original 1977 report and, to our knowledge, represents the first 5-year review of total fundoplication gastroplasty. Three hundred fifty-one consecutive patients with intractable reflux were preoperatively evaluated by history, radiographic studies, manometric studies with determination of pH, and esophagogastroduodenoscopy prior to surgical management by total fundoplication gastroplasty. There were no operative deaths. Follow-up averaged 6.5 years with an effective clinical review available for 95.4% of the patients, radiographic studies for 92.3%, and manometric studies with pH evaluation for 70.7%. Among the 335 patients with 5 or more years of follow-up, 93.1% had excellent results with normal eating and no investigative evidence of recurrence of reflux, 4.0% had mild residual symptoms, and 2.9% had persistent or recurrent symptoms. With this technique, the problems of overcompetence and dysphagia are substantially reduced because the completion fundoplication is tailored to a length of 1 cm while anatomical stability is maintained with a long intraabdominal segment.

Adolescent↗
PubMed1985

Transabdominal total fundoplication gastroplasty to control reflux: a preliminary report.

Transthoracic total fundoplication gastroplasty has been reported as having a low mortality and a 1.1% recurrence rate and to produce excellent results in 93.1% of patients, moderate results in 3.7% and poor results in only 2.8% of patients. In approximately 7.0% intercostal neuritis is a serious residual problem. The transabdominal total fundoplication gastroplasty uses the identical repair technique but avoids the chest-wall pain. Previous esophageal or gastric surgery and major esophageal shortening are contraindications to an abdominal approach. The authors report their results with 50 patients who underwent transabdominal total fundoplication gastroplasty and were followed up for 6 to 20 months. There was no mortality or major morbidity. Clinical follow-up was complete, 94% of patients were assessed by roentgenography and 72% by manometry. None had anatomic recurrence, 46 (92%) were asymptomatic and 4 (8%) had minor residual gastric symptoms of fullness or occasional epigastric pain. All were much improved and none had wound pain. Long-term follow-up of transabdominal total fundoplication gastroplasty is necessary; however, since the technique of repair is identical to the thoracic approach, the results should be similar.

Adolescent↗