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Dive into the research topics where Frederick Alexander is active.

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Featured researches published by Frederick Alexander.


Surgery | 1997

Delayed gastric emptying affects outcome of Nissen fundoplication in neurologically impaired children

Frederick Alexander; Robert Wyllie; Kathleen Jirousek; Michelle Secic; Stacey Porvasnik

BACKGROUND Nissen fundoplication (NF) has a relatively high failure rate in neurologically impaired children with gastroesophageal reflux (GER). In 1990 we began to use routine technetium 99m sulfur colloid emptying scans and pyloroplasty with NF for delayed gastric emptying (DGE) in our neurologically impaired patients. The aim of this study was to determine the influence of DGE and pyloroplasty on the outcome of NF in neurologically impaired children. METHODS One hundred neurologically impaired children underwent NF by a single surgeon between August 1986 and July 1995. Beginning in January 1990 emptying scans were routinely obtained, and patients with DGE underwent pyloroplasty with NF. Outcome analysis was performed for recurrence/wrap failure and other parameters. Mean follow-up was 5.8 years, with a minimum of 18 months. RESULTS DGE was found in 35 (65%) of the 54 children who had emptying scans. All 11 children with normal scans had successful NF without recurrent reflux (100%). Forty (93%) of 43 children who underwent pyloroplasty and NF had successful outcomes. Thirty-eight children underwent NF without evaluation of gastric emptying with success in 30 of them (78.9%). Overall success improved from 34 (83%) of 41 in the first half of the study, when 3 (7%) of 41 children underwent emptying scans, to 55 (93%) of 59 in the second half, when 51 (86%) of 59 of the children underwent emptying scans. CONCLUSIONS DGE is common in neurologically impaired children with GER. NF in children with normal gastric emptying has a high probability of success. Pyloroplasty improves the outcome of NF in children with DGE. Neurologically impaired children should be evaluated for DGE before operation for GER.


Journal of Pediatric Gastroenterology and Nutrition | 1999

Incidence of Dysplasia in Pelvic Pouches in Pediatric Patients After Ileal Pouch-anal Anastomosis for Ulcerative Colitis

Samra Sarigol; Robert Wyllie; Terry Gramlich; Frederick Alexander; Victor W. Fazio; Marsha Kay; Lori Mahajan

BACKGROUND The purpose of this study was to evaluate the incidence of dysplasia and the mucosal adaptation patterns of pelvic pouches in children and adolescents who had undergone ileal pouch-anal anastomosis for ulcerative colitis. METHODS Between 1982 and 1996, 176 pediatric patients with ulcerative colitis underwent ilial pouch-anal anastomosis. Seventy-six patients were followed up after surgery at the Cleveland Clinic. Pouch biopsy specimens were reviewed for dysplasia and to determine mucosal adaptation patterns. Fifty-eight of the 76 patients had an average of three mucosal biopsies during a mean follow-up of 5 years. Demographic and surgical data were abstracted from archives of medical records. All previously obtained pouch biopsy specimens were re-evaluated by a single pathologist to ensure standardized interpretation. RESULTS No dysplasia was identified in screening specimens of 76 children and adolescents including 5 patients who showed dysplasia in resected colon specimens. The pattern of mucosal adaptation was categorized using previously reported criteria. Type A was defined as normal mucosa or mild villous atrophy with no or mild inflammation. Type B mucosa showed transient atrophy with temporary moderate inflammation followed by normalization of architecture. Type C mucosa was defined as a pattern of persistent atrophy with severe inflammation. In the study cohort, the patterns of mucosal adaptation, type A (56.9%; n = 33), type B (32.8%; n = 19), and type C (10.3%; n = 6), were comparable with those reported in adults. The rate of pouch failure and diagnosis of Crohns disease were similar in each group and were not related to the specific adaptation pattern. Most of the patients with type C mucosa had clinical symptoms of pouchitis requiring periodic antibiotic therapy. No dysplasia was identified in any biopsy specimen reviewed. CONCLUSIONS Similar morphologic changes can be seen in ileal pouches in pediatric and adult patients. There seemed to be no increased risk of dysplasia in children and young adults who had undergone ilial pouch-anal anastomosis surgery for ulcerative colitis during a 5 year follow-up. Because the long-term risk of development of dysplasia is unknown, an initial screening should be performed 5 years after the creation of a pelvic pouch in children or when the total disease duration exceeds 7 years. Once identified, patients with Type C mucosa should have annual screening for dysplasia until further data become available.


Journal of Pediatric Surgery | 1985

The critical level for preservation of continence in the ileoanal anastomosis

Lester W. Martin; A. Margarita Torres; Josef E. Fischer; Frederick Alexander

Mucosal proctectomy with ileoanal anastomosis was performed for 90 patients with ulcerative colitis or polyposis over the past 18 years. In three, the anastomosis was at the dentate line. All three had varying degrees of soilage necessitating permanent ileostomy in one. For 12 patients with the anastomosis 1.0 cm proximal to the top of the columns, all were totally continent, but six experienced recurrent disease. For 75 in the third group, the anastomosis was at the top of the columns. Five await ileostomy closure. Of the other 70, none experienced recurrent disease and three have mild nighttime soilage, two of which are less than 1 year following operation. We recommend that the transitional epithelium of the anorectal columns be preserved.


Journal of Trauma-injury Infection and Critical Care | 1984

Arachidonic acid metabolites mediate early burn edema.

Frederick Alexander; Mary A. Mathieson; K. H. T. Teoh; William V. Huval; Lelcuk S; C. R. Valeri; David Shepro; Herbert B. Hechtman

Standard burns were sequentially produced on the backs of Sprague-Dawley rats at 0, 1, 2, and 2 1/2 hr, followed by the IV injection of Evans blue dye. All animals were killed at 3 hr, and burns evaluated by wet/dry weight ratios, and Evans blue extravasation scored 1-4 by two observers. Five groups of rats were compared to controls. Rats made neutropenic by exposure to 137cesium showed no significant difference in wet/dry weight ratio or Evans blue extravasation compared to controls. At 1 1/2 hr four other groups were treated with various inhibitors of arachidonic acid metabolism including ibuprofen, a cyclo-oxygenase inhibitor; FPL 55712, a leukotriene (LT) receptor antagonist; ketoconazole, an inhibitor of thromboxane (Tx) synthetase; and lodoxamide, a calcium channel inhibitor. All treated groups showed significant reduction of Evans blue dye extravasation. Wet/dry weight ratios were significantly reduced in rats treated with FPL 55712 and ketoconazole before or after burning. These data support the postulate that oxygenation products of arachidonic acid, particularly Tx and LT, are important mediators in early burn edema.


Annals of Surgery | 1985

Thromboxane A2 moderates permeability after limb ischemia.

Lelcuk S; Frederick Alexander; C. Robert Valeri; David Shepro; Herbert B. Hechtman

Reperfusion after limb ischemia results in muscle edema as well as excess secretion of thromboxane A2 (TxA2), an agent associated with permeability increase in other settings. This study tests whether TxA2 moderates the permeability following limb ischemia. A tourniquet inflated to 300 mmHg was applied for 2 hours around the hind limb of four groups of dogs. In untreated animals (N = 25), 2 hours following tourniquet release, plasma TxB2 values rose from 320 pg/ml to 2416 pg/ml (p less than 0.001), and popliteal lymph values rose from 378 pg/ml to 1046 pg/ml (p less than 0.001). Platelet TxB2 was unaltered and plasma 6-keto-PGF1 alpha levels did not vary. Following ischemia, lymph flow (QL) increased from 0.07 to 0.37 ml/h (p less than 0.05), while the lymph/plasma (L/P) protein ratio was unchanged at 0.41. These measurements indicate increased permeability since increase in hydrostatic pressure in a second group by tourniquet inflation to 50 mmHg (N = 7) led to a rise in QL from 0.07 to 0.22 ml/h, but a fall in the L/P ratio to 0.32, a value lower than the ischemic group (p less than 0.05). Pretreatment with the imidazole derivative ketoconazole (N = 11) reduced platelet Tx synthesis from 42 ng to 2 ng/10(9) platelets, but lymph TxB2 levels rose to 1703 pg/ml after ischemia, indicating an extravascular or vessel wall site of synthesis not inhibited by ketoconazole. Pretreatment with a lower molecular weight imidazole derivative OKY 046 (N = 9) inhibited all Tx synthesis after ischemia. Prior to tourniquet inflation, both OKY 046 and ketoconazole lowered plasma TxB2 levels as well as the L/P ratio (p less than 0.05). After ischemia, OKY 046, but not ketoconazole, maintained the L/P ratio at 0.33, a value below that of untreated animals (p less than 0.05). These results indicate that nonplatelet-derived TxA2 modulates both baseline and ischemia-induced increases in microvascular permeability in the dog hind limb.


Journal of Pediatric Surgery | 1996

The spectrum of ureteropelvic junction obstructions occurring in duplicated collecting systems

James Ulchaker; Jonathan H. Ross; Frederick Alexander; Robert M. Kay

The authors reviewed four cases of ureteropelvic junction obstruction (UPJ) in duplicated systems. Associated abnormalities included contralateral duplication, vesicoureteral reflux, and a case of ipsilateral upper pole ectopic ureter with a dysplastic upper pole moiety. Surgical management included dismembered pyeloplasty, ureteral reimplantation, end-to-side pyeloureterostomy to the upper-pole ureter, and upper-pole heminephrectomy with lower-pole dismembered pyeloplasty. UPJ obstructions occurring in duplicated systems often are associated with other anomalies.


Annals of Surgery | 1986

Anal continence following Soave procedure. Analysis of results in 100 patients.

Lester W. Martin; Josef E. Fischer; Hazel J. Sayers; Frederick Alexander; Margarita A. Torres

The Soave procedure is an increasingly popular procedure for the definitive therapy of patients with ulcerative colitis. The authors present their experience with 100 patients in whom total proctocolectomy, rectal mucosal stripping, and ileoanal anastomosis (generally using an S-pouch) were carried out. The physiological and anatomical basis of continence is presented, and anastomosis at the top of the columns of Morgagni is recommended. Of the 100 patients in whom this procedure was performed, there was no mortality either in-hospital or later. Of the 12 patients in whom the anastomosis was done 1 cm above the top of the columns (and thus columnar epithelium was retained), six have recurrent anorectal disease, but all are continent both day and night. Three patients in whom the anastomosis was done at the dentate line have had difficulty with continence; two are now continent, but one, after being totally incontinent for 4 years, has required a permanent ileostomy. Of the 69 patients in whom the anastomosis was done at the top of the columns of Morgagni, five are incontinent at night only and two have seepage during both day and night. Thus, if the anastomosis is done at the level recommended, namely, at the top of the columns of Morgagni, retaining no columnar epithelium and anastomosing the ileal pouch to transitional epithelium (which the authors believe not to be subject to the disease of ulcerative colitis), daytime continence will be achieved in 97% and total day and night continence in 90%. The evidence presented suggests that a properly done pull-through procedure with ileoanal anastomosis is the procedure of choice for ulcerative colitis.


Journal of Pediatric Surgery | 1994

Results of mucosal proctectomy versus extrarectal dissection for ulcerative colitis and familial polyposis in children and young adults

Chris Davis; Frederick Alexander; Ian C. Lavery; Victor W. Fazio

Over a 5-year period, the authors examined 30 consecutively treated patients, aged 16 years or younger, who underwent total colectomy and ileal pouch-anal anastomosis, (IPAA) using two different surgical methods. In 16 patients (group I), extrarectal dissection with stapled J pouch and anastomosis was performed. In 14 patients (group II), mucosal proctectomy with hand-sewn S pouch and anastomosis was performed. The mean follow-up period this study was approximately two years (range, 1 to 5 years). With regard to postoperative complications, quality of life, and occurrence of pouchitis, there were no significant differences between the groups. Stool frequency was not significantly different between the two groups, and approached four bowel movements per day at 1 year after surgery. In both groups, daytime continence was achieved by all patients 6 months after surgery. A greater number of patients in group II demonstrated temporary nocturnal leakage than in group I, but this difference was not statistically significant (P = .09). The authors conclude that both methods of IPAA are equally effective in preserving normal sphincter function. In patients with severe rectal inflammation, extrarectal dissection with stapled anastomosis may obviate the need for extended preoperative hyperalimentation or subtotal colectomy, but may carry a small increased risk of recurrent anorectal inflammation. The long-term risk of dysplasia is unknown, but may be slightly higher after extrarectal dissection with stapled anastomosis. Further study of both methods of IPAA is recommended.


Journal of Pediatric Surgery | 1994

Cloacal anomalies: Role of vesicostomy

Frederick Alexander; Robert M. Kay

The purpose of this report is to discuss the use of vesicostomy in the treatment of cloacal anomalies. In 4 years, the authors have performed primary reconstruction in four children who had cloacal anomalies. Three children had hydrocolpos, which in two cases failed to decompress with tube vaginostomy or clean intermittent catheterization. In both cases, cutaneous vesicostomy effectively prevented urinary sepsis, which allowed the children to thrive before definitive reconstruction was performed. Vesicostomy is technically simple to perform and is easily reversed without loss of bladder volume. Further, it lends itself well to definitive reconstruction of cloacal anomalies.


The Journal of Urology | 1999

RISK OF CONTRALATERAL HYDROCELE OR HERNIA AFTER UNILATERAL HYDROCELE REPAIR IN CHILDREN

Laura Lym; Jonathan H. Ross; Frederick Alexander; Robert M. Kay

PURPOSE Recent laparoscopic studies indicate a high incidence of a contralateral open internal ring in children undergoing unilateral hydrocele or hernia repair, raising the question of whether routine contralateral exploration should be done. Data on the long-term risk of clinical contralateral hernia or hydrocele after unilateral hydrocele repair are limited. To address this question we performed long-term followup in patients who underwent unilateral hydrocele repair. MATERIALS AND METHODS We followed patients who previously underwent unilateral hydrocele repair performed by one of us before 1997. Patients were interviewed by telephone and encouraged to return to one of us or their pediatrician for evaluation. RESULTS Of the 101 patients who fulfilled study inclusion criteria 85 who were 5 to 107 months old (median age 37) at the original surgery were successfully contacted, including 45 examined by one of us or a pediatrician and 40 followed by telephone interview only. Contralateral hydrocele or hernia developed in 6 of the 89 patients (7%) 6 to 15 months (median 12) postoperatively. The remaining 79 patients have been recurrence-free for 6 to 153 months (mean 44, median 37). Of the patients 5 of 32 are (15%) and 1 of 53 (2%) who underwent left and right hydrocele repair, respectively, had contralateral recurrence. CONCLUSIONS The risk of a clinically evident contralateral hydrocele or hernia after unilateral hydrocele repair is approximately 7%. We do not recommend routine contralateral exploration in children undergoing unilateral hydrocele repair.

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Herbert B. Hechtman

Brigham and Women's Hospital

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Robert M. Kay

University of Southern California

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