PubMed Health⌕ Search

Biomedical subjects

M N Gomes

Publications and source records attributed to M N Gomes.

At least 19 recordsLinked to original sources
PubMed2000

Management of aberrant subclavian artery aneurysms.

An aberrant subclavian artery is the most common congenital anomaly of the aortic arch. Aneurysms of these vessels are relatively rare lesions. A high clinical suspicion must be maintained in patients with an abnormal mediastinum on chest X-ray, especially in patients with dysphagia, dyspnea, or upper extremity ischemic symptoms not otherwise explained. Potentially disastrous complications, including spontaneous rupture and perforation into the esophagus may occur, and are invariably fatal. We present the case of an 1 asymptomatic 72-year-old male with an aberrant right c subclavian artery aneurysm presenting as a mediastinal mass on routine chest X-ray. Repair was by aneurysmectomy through a left thoracotomy and right common carotid artery to subclavian artery bypass via median sternotomy with resolution of his symptoms. We reviewed 74 cases in the English literature to February 1998. The pertinent anatomy is discussed and trends in surgical treatment are identified. Recent agreement on the surgical approach and choice of revascularization appears to exist, but advances in diagnostic and interventional radiologic capabilities have increased the number of asymptomatic lesions encountered and may alter the treatment of this lesion in the near future.

Aged↗
PubMed1998

A comparison of the reliability of two techniques of left double-lumen tube bronchial cuff inflation in producing water-tight seal of the left mainstem bronchus.

UNLABELLED: A double-lumen endobronchial tube (DLT) bronchial cuff inflation technique that reliably ensures effective water-tight isolation of the two lungs has not been determined. In this study, 20 patients undergoing thoracic surgery requiring a left DLT had the bronchial cuff of the DLT inflated by one of two techniques. In Group 1, the cuff was inflated to produce an air-tight seal of the left bronchus using the underwater seal technique. In Group 2, the cuff was inflated to a pressure of 25 cm H2O. After bronchial cuff inflation in both groups, water-tight bronchial seal was tested by instilling 2 mL of 0.01% methylene blue (MB) above the bronchial cuff of the DLT. Fifteen minutes later, fiberoptic bronchoscopy was performed via the bronchial lumen of the DLT to determine whether MB had seeped past the bronchial cuff. Cuff volume was 0.75+/-0.64 and 0.76+/-0.46 mL, cuff pressure was 30.1+/-27.0 and 25.0+/-0.0 cm H2O (mean+/-SD), and MB was positively identified in two and five patients in Groups 1 and 2, respectively. The difference in cuff volume and pressure and the higher MB seepage in Group 2 compared with Group 1 was not statistically significant. In both groups, MB seepage occurred only when the bronchial cuff volume was <1 mL and when the patients were positioned in the left lateral decubitus position. These findings suggest that the risk of aspiration is greatest when the DLT is positioned in the dependent lung and when the bronchial cuff volume is <1 mL. IMPLICATIONS: Water-tight sealing of the left bronchus by DLT bronchial cuff was tested after cuff inflation using two different techniques. Neither air-tight bronchial seal nor cuff pressure of 25 cm H2O guaranteed protection against aspiration. The risk of aspiration was greatest when the DLT was positioned in the dependent lung and when the bronchial cuff volume was < 1 mL.

Aged↗
PubMed1997

Solitary fibrous tumors: a series of lesions, some in unusual sites.

Solitary fibrous tumor (SFT) is a rare neoplasm that, in addition to its classic presentation as a pleural-based mass, can also be encountered in unusual sites. The main difficulty in making the diagnosis of SFTs results from the unfamiliarity with its diverse clinical and pathologic features. This series of SFTs, some with unusual clinicopathologic presentation, included nine women and two men, ranging in age from 28 years to 74 years (five in pleura, one in lung parenchyma, one in breast, and four in mediastinum). The tumors were locally excised in eight cases and were resected along with portions of lung parenchyma in three. A panel of immunohistochemical stains was used to characterize these tumors. They were all vimentin-positive and, with the exception of one case, CD34-positive. Tumors were negative with antibodies directed against cytokeratin, factor VIII-related antigen, S-100 protein, muscle-specific actin, and smooth-muscle actin. Various diagnoses were initially rendered for these clinically and pathologically diverse lesions by the examining pathologists. Awareness of the various gross and microscopic patterns of these tumors, the possibility of occurring in unusual sites, and the use of immunohistochemical stains, particularly CD34, should eliminate most of the difficulties in arriving at a correct diagnosis. One patient died of metastatic breast cancer; all other patients were alive and well with a median follow-up of 17 months.

Adult↗
PubMed1995

Endoscopic ultrasound for staging esophageal cancer, with or without dilation, is clinically important and safe.

BACKGROUND: To fully evaluate patients with esophageal cancer by endoscopic ultrasonography (EUS), the transducer must pass through the entire tumor to the cardia to scan the celiac axis. Dilation may be necessary. Published information suggests that dilation with EUS carries a sizeable risk. METHODS: In order to assess the complication rate associated with dilation prior to EUS in patients with esophageal cancer and the clinical significance of dilation for complete EUS staging, we reviewed the records of all patients who had undergone EUS for esophageal cancer. RESULTS: Sixty-three patients underwent EUS staging of esophageal cancer. Thirty-nine (62%) had lesions through which the EUS scope was passable (Group I). Ten (16%) patients (Group II) had lesions through which an EUS scope (diameter 13 mm) was unable to pass even after dilation. Fourteen patients (22%) had lesions that were dilated to allow passage of the EUS scope (Group III). All patients in Groups II and III had confirmation of EUS staging by CT and/or surgery. In Group II, five patients had tumors defined as T4 (50%) and five as T3 (50%). In Group III, nine (64%) had T4 tumors, four (29%) had T3, and one (7.7%) had T2. No complications were encountered in any group. CONCLUSION: EUS, either alone or after dilation, is a safe procedure and the complete EUS examination with celiac node visualization adds prognostically significant information.

Adult↗
PubMed1995

Abdominal aortic aneurysms: findings on three-dimensional display of helical CT data.

Excellent vascular opacification, reduction in misregistration artifacts, and the option of reconstructing overlapping scans from which three-dimensional (3D) models of the abdominal vessels may be rendered are among the benefits of helical CT [1-4]. The purpose of this essay is to illustrate the findings of 3D rendering of helical CT data in patients with abdominal aortic aneurysms.

Aortic Aneurysm, Abdominal↗
PubMed1995

Diagnosis of aortic dissection: value of helical CT with multiplanar reformation and three-dimensional rendering.

OBJECTIVE: Twenty-three patients with suspected aortic dissection were evaluated in this preliminary study of helical CT to determine the usefulness of axial sections, multiplanar reformation, and three-dimensional (3D) rendering in assessing the presence of dissection and the extent of intimal flap. MATERIALS AND METHODS: Patients were referred for helical CT scanning because of chest pain or an abnormal chest radiograph. Scans were performed during bolus injection of nonionic contrast material at 2.0-2.5 ml/sec using a mean scan delay of 47 sec. Axial scans with 5-mm collimation were obtained in all patients. They extended from the great vessels to the distal thoracic aorta just above the hiatus. Delayed nonhelical sections were obtained through the upper abdomen. Multiplanar reformations and 3D models were reconstructed from the helical data in 13 patients and were compared to axial sections in 7 patients who proved to have documented dissection. The efficacy of CT was determined using surgery, angiography, or clinical outcome to establish the diagnosis. RESULTS: Of the 23 patients studied, axial sections resulted in 15 true-negative, 7 true-positive, and 1 false-positive interpretation. In three of seven patients with dissection, it was difficult to determine the extent of the intimal flap on axial sections; multiplanar reformation or 3D views clarified the relevant anatomy in all 3 cases. Among the 3D display methods, ray-sum projection views were superior to surface model or maximum-intensity-projection views. CONCLUSION: If studies of larger numbers of patients confirm our preliminary findings, multiplanar reformation and 3D rendering of helical CT scans will be a valuable addition to axial display of CT studies used to detect aortic dissection and to determine the extent of the intimal flap.

Adult↗
PubMed1994

Preoperative assessment of abdominal aortic aneurysm: the value of helical and three-dimensional computed tomography.

PURPOSE: The purpose of this study was to evaluate the utility of helical computed tomography (CT) in the preoperative assessment of abdominal aortic aneurysms (AAA) and to compare its accuracy with aortography and operative findings. METHODS: Thirty-two patients with suspected AAA were evaluated by helical CT with either 5 mm collimation (slice thickness) or a combination of 3 mm collimation through the renal and mesenteric arteries and 7 mm collimation through the remainder of the AAA. Three-dimensional reconstructions were performed with use of three different techniques, and results were compared with aortography and surgery. RESULTS: Twenty-five patients were found to have an aneurysm, and 19 subsequently underwent surgery. Standard angiography was also performed in 13. The location, size, and extent of the aneurysm, as well as the wall calcification and intraaneurysmal thrombus, were well depicted with helical CT. The visceral aortic branches, including the detection of renal artery stenosis and accessory renal arteries, were consistently seen with the 3 mm/7 mm collimation protocol and three-dimensional reconstruction. CONCLUSION: Helical CT with three-dimensional display of the aorta and its branches combines the advantages of conventional CT imaging and aortography. This technique appears to provide comprehensive preoperative evaluation of AAA.

Aged↗
PubMed1994

Abdominal aortic aneurysms: evaluation with variable-collimation helical CT and overlapping reconstruction.

PURPOSE: To determine the value of variable collimation and overlapping reconstruction in helical computed tomography (CT) to evaluate abdominal aortic aneurysm. MATERIALS AND METHODS: Twenty-three patients (15 men and eight women, aged 59-85 years) underwent helical CT scanning, nine with fixed 5-mm collimation and 14 with 3- and 7-mm collimation combined. The ability to visualize main and accessory renal arteries, detect stenoses, and determine aneurysm extent were evaluated. RESULTS: Extent of aneurysm was accurately determined in 17 of 23 cases without overlapping sections; failure to detect ancillary findings such as accessory arteries or stenosis occurred in nine of these cases. With overlapping sections, determination of aneurysm extent improved to 19 of 23 cases and ancillary errors were reduced to four. Five errors occurred with fixed collimation and three errors with variable collimation. CONCLUSION: Overlapping, variable-collimation helical CT allows for a more complete evaluation of abdominal aortic aneurysms than does nonoverlapping, fixed-collimation CT.

Aged↗
PubMed1994

Pedicled muscle flaps in the management of infected aortofemoral grafts.

Graft infection, although uncommon, is a serious complication of reconstructive vascular surgery, associated with a high mortality and limb loss in a large percentage of the survivors. Although débridement and drainage, specific systemic antibiotics, removal of the entire infected graft and revascularization by extra-anatomic bypass are the general principles of management, this technique has its limitations and in certain circumstances is not feasible. The use of well-vascularized autogenous tissue as coverage of infected grafts has been successful in the lower extremities, with graft and limb salvage, but not when the infection extends above the inguinal ligament. Instances where the infection at the inguinal area extends retrograde along the limb of the aortofemoral graft represent a greater therapeutic challenge. In two instances, a dual muscle flap was used successfully to cover the exposed prosthesis after complete débridement of the perigraft granulation tissue. Sartorius and rectus femoris muscles, with their blood supply, were mobilized and rotated to cover the distal anastomosis and the retroperitoneally exposed graft respectively, with primary wound closure. All flaps survived and the patent grafts were salvaged. There was no long-term functional deficit from the transposition of these muscles. Pedicled muscle flaps appear to be a well-tolerated method of achieving autogenous tissue coverage of an infected graft in the groin, and retroperitoneal portions and should be considered a satisfactory alternative when the traditional methods of management cannot be applied.

Aorta, Abdominal↗
PubMed1993

Salmonella aortitis. A report of a successfully treated case with a comprehensive review of the literature.

A successfully treated case of Salmonella infection of the thoracic aorta is described. Salmonella enteritidis was isolated from blood cultures and from operative cultures of the aorta. Computed tomography suggested the site of infection, and the resection of the thoracic aortic aneurysm with specific antibiotic therapy resulted in a satisfactory outcome. Although once invariably fatal, improved diagnostic roentgenographic techniques, more potent antibiotics, and surgical advances have resulted in at least 45 reported survivors over the last 15 years. The pathogenesis, clinical and laboratory characteristics, and the treatment of aortitis due to Salmonella species are reviewed in 98 cases reported in the English-language literature since 1948. Early diagnosis and a combination of prompt surgical intervention and antibiotic therapy are essential for survival.

Aneurysm, Infected↗
PubMed1992

Infected aortic aneurysms. A changing entity.

Infected (mycotic) aortic aneurysms are infrequent and, without surgical intervention, usually lead to uncontrolled sepsis or catastrophic hemorrhage. Symptoms are frequently absent or non-specific during the early stages, and a high index of suspicion is essential to make the diagnosis. Surgery performed after rupture carries high morbidity and mortality rates. Bacterial endocarditis with streptococcus pyogenes was the most common cause of infected aortic aneurysm in the pre-antibiotic era. Today, arterial trauma due to iatrogenic manipulation and depressed immunocompetence have become more common risk factors. Staphylococcus aureus and Salmonella are the most frequent bacteria identified. The authors' recent experience in six patients with infected aortic aneurysms who underwent arteriography and computed tomography was reviewed and these diagnostic methods compared. Computed tomography was found to be more sensitive in the diagnosis of the early stages of the disease, allowing for follow-up by serial scans in a noninvasive and less costly manner. Successful treatment, in four of these patients, was accomplished by aneurysmal resection and extra-anatomic bypass or in situ prosthetic reconstruction. A higher clinical awareness of this disease, leading to early computed tomography evaluation and prompt surgical intervention under appropriate and intensive antibiotic therapy, appears to offer the best chance of survival in patients with this difficult condition.

Aged↗
PubMed1992

Gadolinium-enhanced magnitude contrast MR angiography of popliteal and tibial arteries.

To evaluate the efficacy of gadopentetate dimeglumine in MR angiography of the lower extremities, a flow phantom, seven healthy volunteers, and seven patients with peripheral vascular disease were studied with a magnitude contrast (MC) technique. The combination of an MC rephase-dephase gradient-refocused-echo pulse sequence, a 40-cm-long transmit-receive coil, and intravenous administration of a bolus of gadopentetate dimeglumine improved MR angiographic quality in the phantom, volunteers, and patients. Gadolinium enhancement decreased deleterious saturation effects and improved images of the popliteal and tibioperoneal arteries in the volunteers and patients. However, in some cases, venous overlap, imaging artifacts, and suboptimal visualization of subtle lesions limited interpretation. The authors conclude that gadolinium enhancement combined with an MC subtraction pulse sequence appreciably improves MR angiography of lower extremity arteries.

Arterial Occlusive Diseases↗
PubMed1987

Metastatic cancer. A relative contraindication to vena cava filter placement.

From October 1979 to November 1984, 41 patients underwent placement of vena cava filters for prevention of pulmonary emboli. After filter placement, no pulmonary emboli were documented. No patient died due to filter placement. However, 20 of these 41 patients are dead. Eighteen deaths were caused by cancer. Ten (24%) patients died within 2 months of filter placement. Five (12%) patients died prior to hospital discharge. All ten of these patients had known, widely metastatic cancer. Among the ten patients who died more than 2 months after filter placement, six had well-differentiated, slow growing tumors. Only three of these patients had brain metastases. Among the 21 survivors only two suffered from cancer. Strict adherence to accepted indications for vena cava filter placement required operative procedures on a small but significant number of patients who demonstrated no significant improvement in quality of life or time out of hospital. Filter placement in patients with aggressive cancers and proven metastases should be performed only after analysis of predicted survival and after detailed discussions with patients and referring physicians. Filter placement in patients with aggressive metastatic cancer may cause discomfort, risk, and expense with little hope for improvement of hospital course, longevity, or quality of life.

Adult↗
PubMed1987

Mediastinal tracheostomy.

Upper airway obstruction in primary or recurrent carcinomas of the head and neck extending into the mediastinum may demand surgical intervention despite severe technical difficulties in patients with tumors previously considered inoperable. In fact, many of these tumors may be operable and some perhaps curable. A technique has been developed based in part on our experience with previously described procedures. A preliminary sternal split is used to demonstrate the extent of the mediastinal involvement as well as to provide enhanced exposure and proximal control of the great vessels. The pectoralis major muscle is used with a generous flap of overlying skin comprising nearly half of the anterior portion of the chest. A tracheostomy is then created in a fashion similar to the placement of a cardiac valvular prosthesis by creating a circular defect in the pectoralis major flap and suturing it to the tracheal remnant. This technique offers a reasonably safe and reliable means of creating a low anterior mediastinal tracheostomy for tumors previously considered inoperable. The preliminary sternal split makes the procedure safer and easier to perform, and the use of a very large pectoralis major island flap allows for reliable closure of the resulting mediastinal and sternal defects.

Aged↗