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Biomedical subjects

R A Prinz

Publications and source records attributed to R A Prinz.

At least 19 recordsLinked to original sources
PubMed2000

Intraoperative sestamibi scanning in reoperative parathyroidectomy.

BACKGROUND: Reoperative neck exploration for hyperparathyroidism is often difficult even for experienced surgeons. Recent advances in preoperative and intraoperative localization techniques have improved successful resection rates. This prospective study evaluates the accuracy and clinical utility of intraoperative technetium 99m sestamibi scanning for localizing hyperfunctioning parathyroid tissue in reoperative neck explorations. PATIENTS AND METHODS: Eleven patients underwent reoperative neck exploration for hyperparathyroidism. Two patients had 3 prior neck explorations, 1 had 2 prior neck explorations, and 8 patients had 1 prior neck operation. Preoperative studies included sestamibi scintigraphy and ultrasound in all patients, magnetic resonance imaging in 4, computed tomography scan in 3, parathyroid arteriogram in 1, and selective venous sampling in 1. All patients underwent intraoperative technetium 99m sestamibi scanning and parathyroid hormone assay. RESULTS: Preoperative technetium 99m sestamibi scanning and ultrasound each successfully localized 7 of 11 hyperfunctioning glands (64%). Intraoperative technetium 99m sestamibi scanning correctly localized 10 of 11 hyperfunctioning glands (91%). Intraoperative parathyroid hormone assay confirmed successful excision of hyperfunctioning tissue in all 11 patients. Postoperatively, all 11 patients had low-normal or normal calcium levels. CONCLUSIONS: Intraoperative technetium 99m sestamibi correctly localized 91% of hyperfunctioning glands compared with 64% localization for preoperative technetium 99m sestamibi and preoperative ultrasound. Intraoperative technetium 99m sestamibi scanning and parathyroid hormone monitoring are useful in reoperative neck explorations for hyperparathyroidism.

Adult↗
PubMed2000

Normalization of intraoperative parathyroid hormone does not predict normal postoperative parathyroid hormone levels.

BACKGROUND: Intraoperative intact parathyroid hormone (iPTH) is being used to confirm complete excision of hyperfunctioning parathyroid tissue. It is uncertain whether normalization of intraoperative iPTH levels accurately predicts long-term postoperative iPTH values. METHODS: Fifty-two consecutive patients with primary or secondary hyperparathyroidism underwent parathyroidectomy with measurement of intraoperative iPTH. Ten patients were excluded due to incomplete laboratory follow-up. Follow-up serum calcium and iPTH levels were measured at 1- and 3-month intervals. RESULTS: Before operation, the mean serum iPTH level was 249 pg/mL (SD=208) and mean serum calcium level was 11.4 +/- 0.9 mg/dL (+/- SD). In all but 4 patients, final intraoperative iPTH levels normalized to less than 67 +/- 41 pg/mL (mean, 35 pg/mL). One week after operation, serum calcium levels had returned to normal (mean, 9.4 +/- 1.1 pg/mL), which directly correlated with the final intraoperative serum iPTH values (Pearson correlation, r = -.434; P <.01). By 1 month, all but 2 patients were normocalcemic (mean, 9.4 +/- 0.9 pg/mL) with a mean iPTH level of 74.8 +/- 82 pg/mL. There was no correlation between final intraoperative and postoperative serum iPTH values (r =.099; P <.533). Both patients with persistent hypercalcemia at 1 month had appropriate intraoperative decreases in iPTH values. CONCLUSIONS: Intraoperative serum iPTH levels significantly correlate with postoperative serum calcium levels but not with postoperative serum iPTH levels. There was a 4.8% failure rate in the correction of postoperative serum calcium levels and a 29% failure rate in the normalization of postoperative serum iPTH levels.

Adolescent↗
PubMed2000

The effect of interleukin-6 on bacterial translocation in acute canine pancreatitis.

BACKGROUND: Bacterial translocation from the gut to mesenteric lymph nodes and other extraintestinal sites is an important source of infection in acute pancreatitis. Impaired host immunity is known to promote bacterial translocation. Interleukin-6 (IL-6) is a multifunctional cytokine that regulates the immune response, acute phase reaction, and hematopoiesis. METHODS: Twenty-four mongrel dogs (18-29 kg) were studied in four equal groups. In Groups I and II, acute pancreatitis was induced by direct pressure injection of 4% taurocholate and trypsin into the pancreatic duct at laparotomy. Groups III and IV had only laparotomy. Group I and III dogs were given IL-6 (50 microg/kg/d, sq) daily starting 24 h after operation and Group II and IV dogs received an equal volume of saline administered at similar time. All animals had blood drawn for culture, complete blood count (CBC), platelets, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and amylase on d 0, 1, 4, and 7. On d 7, mesenteric lymph nodes (MLN), spleen, liver, pancreas, and cecum were harvested for pathology study and for cultures of aerobic and anaerobic bacteria. Quantitative cecal cultures of aerobic and anaerobic bacteria were obtained. RESULTS: All Group I and Group II dogs had severe pancreatitis. The increase of plasma CRP in Group I was sustained throughout treatment (1.3+/-0.3 on d 0 vs 3.1+/-0.3*, 3.0+/-0.3*, and 2.9+/-0.3* on d 1,4, and 7, respectively). Plasma CRP was increased in Group II on d 1 and d 4 (1.3+/-0.3 mg/dL on d 0 vs 3.6+/-0.3* mg/dL on d 1, and 3.1+/-0.3* on d 4, *p < 0.05). There were no differences in white blood cell (WBC) count, differential, platelets, and ESR between Groups I and II. Bacterial translocation to MLN was lower in Group I (1/6) than in Group II (6/6) (p < 0.05). All 6 dogs in Group II had bacterial spread to distant sites compared to 2 of 6 dogs in Group I (p = 0.066). Both MLN and other distant organ cultures were negative in Group III and only 1 of 6 MLN cultures was positive in Group IV. CONCLUSIONS: IL-6 treatment decreases bacterial translocation to MLN and may be beneficial in reducing septic complications in acute pancreatitis.

Acute Disease↗
PubMed1999

Laparoscopic adrenalectomy.

Advances in minimally invasive surgery have made it possible to remove solid organs such as the adrenal gland laparoscopically. Several studies have shown that when applied to appropriate operative candidates, laparoscopic adrenalectomy is a safe alternative to conventional open surgery with real advantages in terms of decreasing postoperative pain and length of hospital stay and allowing earlier return to normal activity. The indications for laparoscopic adrenalectomy are essentially the same as those described for open adrenalectomy. We do not recommend laparoscopic adrenalectomy for known primary or metastatic malignant tumors of the adrenal glands, because of the risk of tumor implantation that might compromise the patient's chance for cure, nor do we recommend it for lesions larger than 6 to 8 cm where the chance of malignancy is high. The preoperative preparation, laparoscopic instruments, operative techniques, and potential complications and their treatments are described in this review. Laparoscopic adrenalectomy is becoming the preferred method of surgically treating many adrenal problems. Although conventional surgical approaches will undoubtedly be required to treat certain adrenal lesions, surgeons with an interest in treating patients with adrenal disorders must become proficient in the technique of laparoscopic adrenalectomy. This will allow them to select the most appropriate operative approach for their patients' individual problems.

Adrenalectomy↗
PubMed1999

Endoscopic ultrasound for diagnosis and staging of pancreatic tumors.

Endoscopic ultrasound (EUS) is proving to be a useful tool for evaluation of clinically suspected pancreatic masses unsatisfactorily evaluated by other means of imaging. We reviewed the records of 19 patients who had CT and EUS performed for clinically suspected pancreatic masses. Each patient had subsequent surgical exploration. Nineteen patients (11 females and 8 males) presenting with symptoms (11 with obstructive jaundice, 6 with abdominal pain and weight loss) or incidental CT findings suspicious for pancreatic carcinoma underwent EUS for further pancreatic evaluation. All of these patients had exploratory laparotomies, with 13 pancreaticoduodenectomies, 3 distal pancreatectomies and splenectomies, 1 bypass procedure, 1 open pancreatic and hepatic biopsy showing metastatic disease, and 1 open exploration with negative fine-needle aspiration biopsy. EUS correctly identified pancreatic neoplasms in 17 of 19 cases, with two false positives. The tumors included 15 adenocarcinomas, 1 microcystic adenoma, and 1 lymphoma. Node status was correctly predicted in 9 of 12 specimens. Nine of 12 tumors had accurate tumor staging by EUS. Absence of vascular invasion was accurately predicted in 13 of 14 cases. Two patients had metastatic disease discovered at laparotomy. All 19 patients had preoperative abdominal CT scans, with six of these negative for pancreatic masses. EUS is more sensitive than CT in detecting pancreatic masses and is more accurate than CT in locally staging pancreatic tumors. This higher sensitivity is important because those patients with earlier stage tumors are the most likely to benefit from resection.

Adenocarcinoma↗
PubMed1999

The effect of lexipafant on bacterial translocation in acute necrotizing pancreatitis in rats.

Bacterial translocation (BT) from the gastrointestinal tract to mesenteric lymph nodes (MLNs) and other extra intestinal organs is an important source of infection in acute pancreatitis (AP). Lexipafant (BB-882) is a potent platelet-activating factor receptor antagonist that has an anti-inflammatory effect. To examine whether BB-882 could affect BT in acute necrotizing pancreatitis, 48 male Sprague Dawley rats (250-350 g) were studied. AP was induced in Group I and Group II by pressure injection of 3% taurocholate and trypsin into the common biliopancreatic duct (1 mL/kg of body weight). Group I rats received BB-882 (10 mg/kg, i.p. qd) and Group II rats received a similar volume of normal saline as a placebo postoperatively for 2 days. Group III and Group IV received BB-882 and placebo, respectively, after an exploratory laparotomy. At 48 hours postoperatively, blood was drawn for culture, serum amylase, and tumor necrosis factor (TNF)-alpha determinations. Specimens from MLNs, spleen, liver, pancreas, and cecum were harvested for culture of gram-positive, gram-negative, and anaerobic bacteria. Quantitative cecal cultures of gram-positive, gram-negative, and anaerobic bacteria were obtained. A point scoring system for five histological features that include interstitial edema, inflammatory cellular infiltration, fat necrosis, parenchymal necrosis, and hemorrhage was used to evaluate the severity of pancreatitis. There was no difference in serum amylase levels (2415 +/- 127 IU/L versus 2476 +/- 170 IU/L), serum TNF-alpha levels (7820 +/- 1396 pg/mL versus 7318 +/- 681 pg/mL), and the mean pancreatic histology score (5.9 +/- 1.2 versus 6.5 +/- 1.1) between Group I and Group II, respectively (P > 0.05). Seven of 12 Group I rats had BT to MLNs, compared with 11 of 12 rats in Group II (P > 0.05). Five of 12 Group I rats had BT to distant sites such as pancreas, spleen, liver, and/or blood, compared with 11 of 12 rats in Group II (P < 0.05). BB-882 treatment decreases bacterial spread to distant sites, but does not reduce serum amylase levels and serum TNF-alpha levels or ameliorate pancreatic damage in rats with AP.

Amylases↗
PubMed1999

Prognostic factors associated with resectable adenocarcinoma of the head of the pancreas.

A retrospective study of patients with surgically resectable adenocarcinoma of the pancreatic head was undertaken to determine which prognostic factors are independently associated with improved survival. Thirty-four men and 41 women (mean age, 61.9 years) had resection for adenocarcinoma of the pancreatic head between 1980 and 1997 at Rush-Presbyterian-St. Luke's Medical Center. Surgical resections included 15 total pancreatectomies, 43 pyloric-preserving procedures, and 17 standard Whipple procedures. Thirty-six patients received adjuvant radiation and/or chemotherapy. Overall median survival was 13 months, with a 5-year survival of 17 per cent. Thirty-day surgical mortality was 1.3 per cent. Significant factors that negatively influenced survival using univariate Kaplan-Meier analysis were: positive resection margin (P = 0.01), intraoperative blood transfusion (P = 0.01), and lymph node metastases (P = 0.01). Presenting signs and symptoms, patient demographics, operative procedure, tumor size, histologic differentiation, and adjuvant therapy did not have a significant impact on survival. Using multivariate Cox regression analysis, the only significant independent factors improving survival were the absence of intraoperative blood transfusion (P = 0.02) and a negative resection margin (P = 0.04). Performing pancreaticoduodenectomy for adenocarcinoma of the head of the pancreas with negative microscopic margins of resection and without intraoperative transfusion significantly improves survival.

Adenocarcinoma↗
PubMed1998

Total thyroidectomy for benign thyroid disease.

BACKGROUND: The goal of this study was to evaluate the safety and efficacy of total thyroidectomy performed for benign thyroid disease. METHODS: A total of 106 consecutive patients undergoing total thyroidectomy for benign disease from October 1982 to July 1995 were reviewed. The 33 men and 73 women had an average age of 46 years (range, 16 to 82 years). Indications for total thyroidectomy were a thyroid nodule with the history of head and neck radiation in 36 patients, bilateral thyroid nodules in 35, needle biopsy of a follicular neoplasm or frozen section diagnosis of a possible malignancy in 18, and toxic goiter in 17. Total thyroidectomy was performed as the primary operation in 98 patients, and 8 patients had a completion reoperation for recurrent disease. RESULTS: Pathology findings revealed benign nodular goiter in 49 patients, follicular adenoma in 26, hyperplasia in 19, and Hashimoto's thyroiditis in 12. Postoperative hemorrhage requiring operative hemostasis occurred in two patients (1.9%). Two patients had unilateral recurrent laryngeal nerve (RLN) palsy before operation (1.9%). Three patients had unilateral postoperative RLN palsy (2.8%). Two cases resolved in 3 and 4 months. The only permanent RLN injury occurred in a patient reoperated for a compressive goiter. Early postoperative hypocalcemia (8.0 mg/dl or less) was found in nine patients (8.5%). No patient had permanent hypoparathyroidism at long-term follow-up evaluation. CONCLUSIONS: Total thyroidectomy for benign thyroid disease can avoid reoperation for nodular goiter and hyperthyroidism and eliminate any subsequent risk of malignant change in radiated thyroid glands. A low complication rate can be achieved with meticulous surgical technique. Total thyroidectomy can be performed safely for bilateral benign thyroid disease.

Adenoma↗
PubMed1998

Thyroid reoperations: indications and risks.

Thyroid reoperations can be technically difficult and associated with an increased risk of complications. To determine the indications for reoperations and the risk of postoperative complications with these procedures, records of 362 patients undergoing thyroidectomy by a single surgeon (R.A.P.) were reviewed. Thirty-two patients had a reoperation. The group consists of 21 women and 11 men with an average age of 55 years (range, 31-79). Twenty-four patients had 1 prior operation, and 8 patients had 2 or more. We performed 4 of the initial operations, and 28 were done by surgeons at other centers. Fourteen reoperations were done for symptomatic multinodular goiter (MNG), and 5 because of a change in the histologic diagnosis from benign to cancerous. The remainder were for further treatment of malignancy. The most common operation was completion thyroidectomy (31). In 3 patients, either unilateral or bilateral modified radical neck exploration was performed. One patient required median sternotomy. One subtotal thyroidectomy was also performed. Recurrent laryngeal nerve injury occurred in 2 patients. It resolved in 1 patient but was permanent in another, who had 3 operations for MNG. One of the 2 patients with preoperative unilateral vocal cord paralysis had return of function after removal of a substernal goiter. The other had a permanent nerve injury from the original surgery. Three patients had postoperative hypocalcemia (calcium <8.0 mg/dL). This resolved in all patients within 1 to 6 months. One patient who had a third operation for MNG had postoperative hemorrhage necessitating tracheostomy for airway control. Another patient developed a seroma that resolved within 2 months. We conclude that reoperations are indicated for both benign and malignant thyroid disease. Because they carry a higher risk of complications, every effort should be made to avoid them by performing definitive initial treatment.

Female↗
PubMed1998

Surgical approach to adrenal neoplasms: laparoscopic versus open adrenalectomy.

There are a number of different approaches available to surgically remove the adrenal gland. These can be broadly classified into two general categories, open and laparoscopic. There is no one best method for all patients. Surgeons, skilled in all aspects of adrenal surgery, should choose an approach for adrenalectomy based on patient and tumor related factors. Once advantages and disadvantages of a specific procedure, with these factors in mind, are weighed, the best approach for the individual patient should be chosen.

Adrenal Gland Neoplasms↗
PubMed1997

The effect of epidermal growth factor on the septic complications of acute pancreatitis.

Bacterial translocation (BT) from the gastrointestinal tract to mesenteric lymph nodes (MLN) and other extraintestinal organs is an important source of infection in acute pancreatitis (AP). Epidermal growth factor (EGF), a peptide hormone with trophic effects on gut mucosa, has decreased intestinal mucosal injury in septic rats and decreased burn-induced BT in mice. The purpose of this study is to examine whether EGF could affect BT in acute necrotizing pancreatitis. Forty-eight male Sprague-Dawley rats (250-350 g) were studied. AP was induced in Group I and Group II by pressure injection of 3% taurocholate and trypsin into the biliopancreatic duct (1 ml/kg of body weight). Group III and Group IV underwent laparotomy without induction of acute pancreatitis. Group I rats received human recombinant EGF (100 micrograms/kg, subcutaneously twice daily) and Group II rats received a similar volume of 0.1% bovine serum albumin as a placebo postoperatively. Group III and Group IV received EGF and placebo, respectively. At 48 hr postoperatively, blood was drawn for culture and amylase determinations. Jejunum and ileum were obtained to measure mucosal protein content, mucosal thickness, villus height, and crypt depth. Specimens from MLN, spleen, liver, pancreas, and cecum were harvested for pathology and culture of gram positive (G+), gram negative (G-), and anaerobic bacteria. Ileal mucosal protein levels were increased significantly in Group I (1.96 +/- 0.14 mg/cm) compared to Group II (0.95 +/- 0.15 mg/cm intestinal segment) (P < 0.01). Jejunal and ileal mucosal thickness, villus height, and crypt depth in Group I were significantly increased when compared to Group II (P < 0.05). All 12 rats in Group II had BT to MLN compared to 58% (7 of 12 rats) in Group I (P < 0.05). Thirty-three percent (4 of 12 rats) had BT to distant sites such as pancreas, spleen, liver, and/or blood in Group I vs 83% (10 of 12 rats) in Group II (P < 0.05). EGF treatment minimizes intestinal damage, decreases BT to MLN and bacterial spread to distant sites, and may be beneficial in preventing septic complications in AP.

Acute Disease↗
PubMed1997

User of fine-needle aspiration biopsy and frozen section in the management of the solitary thyroid nodule.

BACKGROUND: This study evaluates the indication for frozen section (FSx) in the management of the solitary thyroid nodule given the increasing use of fine-needle aspiration biopsy (FNAB). METHODS: The charts of 561 patients who underwent thyroidectomy for a solitary nodule were reviewed. Each patient underwent either FNAB, FSx, or both. Results were compared to the final diagnosis to evaluate their effectiveness in predicting malignancy. RESULTS: The sensitivity and specificity for FNAB alone (162 patients) were 86% and 91%, respectively, and for FSx (494 patients) 79% and 99%, respectively. The routine use of FSx with diagnostic FNABs did not improve the accuracy over either test alone. Sensitivity, specificity, and accuracy were essentially unchanged when the use of FSx was limited to just atypical FNAB but dropped significantly when FSx was not used. CONCLUSIONS: When results of FNAB and FSx are interpreted as benign or malignant, both are highly accurate predictors of malignancy. Routine use of FSx and FNAB does not improve the sensitivity or specificity in the detection of malignancy over that of either examination alone. FSx proved useful in determining the extent of operation only when results of the FNAB were atypical.

Biopsy, Needle↗
PubMed1997

Effectiveness of the thyroid scan in evaluation of the solitary thyroid nodule.

Solitary, palpable thyroid nodules are common, but only a small percentage are malignant. It is important to evaluate these nodules in a cost-efficient manner that avoids missing a cancer. Historically, radioisotope imaging has played a major role in the workup of thyroid nodules; however, with the advent of fine needle aspiration biopsy (FNAB), this role has become less clear. From 1974 to 1994, 770 patients with a solitary nodule underwent thyroidectomy. Preoperatively, 471 had thyroid scans, and 149 had FNAB. The incidence of carcinoma in nodules excised on the basis of thyroid scan was 23 per cent, whereas the incidence of carcinoma was 37 per cent when FNAB was used (P = 0.003). Fine needle aspiration was a significantly better predictor of malignancy than thyroid scan and resulted in a smaller proportion of excisions for benign nodules. Thyroid scan provided little additional information in those patients who underwent FNAB. Because thyroid scans add little in determining which nodules require surgical excision, they should no longer be a routine part of the evaluation of a solitary thyroid nodule.

Adolescent↗
PubMed1996

Adrenalectomy in the era of laparoscopy.

BACKGROUND: Recently laparoscopy has been described as an alternative approach for performing adrenalectomy. This study attempts to define the frequency and indications for the various approaches to adrenalectomy including laparoscopy. METHODS: From October 1992 to December 1995, 43 adrenal glands were excised from 40 patients, of whom 23 were women and 17 were men. Their ages ranged from 16 to 71 years. Nineteen operations were performed for pheochromocytoma, 10 for cortical adenoma (CAd), 6 for aldosteronoma, 4 for adrenocortical cancer (ACC), 1 for Cushing's disease (CD), and 1 for hemorrhagic cyst. Adrenalectomy was accomplished via a laparoscopic operation in 20 patients (8 CAds, 6 pheochromocytomas, 5 aldosteronomas, and 1 HC) and via an open operation in 19 patients (11 pheochromocytomas, 4 ACCs, 2 CAds, 1 CD, and 1 aldosteronoma). One patient with bilateral pheochromocytoma had an open and a laparoscopic adrenalectomy. RESULTS: Open operations included 15 transabdominal, 4 posterior, and 3 thoracoabdominal approaches for 22 glands. Laparoscopic operations included 17 transabdominal and 4 retroperitoneal approaches for 21 glands. Reasons for open operations included obesity (1), patient choice (2), failed laparoscopy (2), previous abdominal surgery (3), extraadrenal location (5); and gland size greater than 8 cm (9). Of these cases, the two patient choices, the two failed laparoscopies, and two of the three previous abdominal operations were appropriate for laparoscopy. Each of the posterior approaches could have been done laparoscopically. CONCLUSIONS: More than 60% of surgically treatable adrenal disease may be approached laparoscopically. Transabdominal, and on occasion, thoracoabdominal approaches are indicated for larger adrenal lesions. Surgeons operating on the adrenal gland should be familiar with each of these various approaches for adrenalectomy.

Adolescent↗