Biomedical subjects

K H Lam

Publications and source records attributed to K H Lam.

At least 55 records · Page 3Linked to original sources

PubMed1992

Mirizzi syndrome with cholecystocholedochal fistula: preoperative diagnosis and management.

Gallstone obstruction of the cystic duct with resulting repeated attacks of inflammation and pressure necrosis leads to the formation of cholecystocholedochal fistulas (Mirizzi syndrome type II). Obstructive jaundice and cholangitis are the common presentations of the condition. These fistulas are often not recognized before operation and constitute a high risk of damage to the common duct during a formal cholecystectomy. A high index of suspicion is required to diagnose the condition. We report five patients with cholecystocholedochal fistulas diagnosed by endoscopic retrograde cholangiography that delineated the fistula and the obstructing stone. The plan of management was formulated before surgery, and persistent attempt to dissect the Calot's triangle was avoided. In three patients the common duct defect was closed with the use of a gallbladder flap. Hepaticojejunostomy was required for the two difficult cases with large common duct defects and inflamed tissue.

Aged↗

PubMed1991

Tracheostomal stenosis after immediate tracheoesophageal puncture.

The incidence of tracheostomal stenosis in a group of patients after total laryngectomy with or without pharyngectomy plus immediate tracheoesophageal or tracheogastric puncture was compared with that of a control group without puncture. The stenosis rate of the puncture group was significantly higher than that of the control group (19% vs 6%). The other probable etiologic factors for stomal stricture were similar in both groups. Analysis of the risk factors in the puncture group suggested a higher tendency of stenosis in females (43% vs 16%) and in patients receiving postoperative radiotherapy (29% vs 14%), although the difference failed to reach statistical significance.

Adult↗

PubMed1991

Radical neck dissection in nasopharyngeal carcinoma.

We report a series of 37 patients who had radical neck dissection for residual or recurrent lymph node metastasis from nasopharyngeal carcinoma after radiotherapy. The operation was performed despite high doses of pre-operative radiotherapy. There was no operative mortality and the morbidity was 13% (2 prolonged chylous drainage, 3 sloughing of neck flap). The risk of sloughing of neck flap was significantly related to previous lymph node biopsy, which should be avoided if at all possible. In 35% of patients, the lymph node was densely adherent to neighbouring structures. In the 28 patients who had single lymph node clinically, 29% had multiple neck node involvement noted during operation; another 14% were documented only on histological examination. Radical neck dissection rather than excision alone is justified for the clinically solitary lymph node.

Adult↗

PubMed1991

Plea for selective operative cholangiography.

A prospective study was carried out to evaluate the use of routine operative cholangiography in 382 patients undergoing elective cholecystectomy. Operative cholangiography was performed in 356 patients. In each patient, the presence or absence of clinical and operative indications for common duct exploration was correlated with the result of the operative cholangiography. In 114 patients (32%) there were one or more indications for exploration and only 34 patients showed positive cholangiographic findings and were explored. Ductal stones were found in 25 patients and nine patients had negative explorations. In the remaining 242 patients who had no indication for common duct exploration, normal cholangiogram was obtained in 234 patients and eight had false positive cholangiograms and were explored unnecessarily. No unsuspected common duct stones were detected in the whole series. Based on these results, a plea is made for selective operative cholangiography.

Cholangiography↗

PubMed1990

Split-palate approach for gold grain implantation in nasopharyngeal carcinoma.

Although nasopharyngeal carcinoma is radiosensitive, local failure after external radiotherapy is not uncommon and management of persistent or recurrent disease is a therapeutic challenge. The present review reports the use of brachy-therapy in the form of gold grain (198Au) implants in the treatment of 23 patients with recurrent or persistent primary nasopharyngeal carcinoma. The split-palate approach was employed in the insertion of the gold grains. This approach allows adequate exposure of the nasopharynx and accurate positioning of the implants. Implantation was successful in 21 patients, and local tumor control was achieved in 17 patients (81%) after a median follow-up of 23 months. Palatal fistula developed in 6 patients (26%): 5 healed with conservative management, and 1 had no functional disturbance. There was no operative mortality, and morbidity of the operation was minimal.

Brachytherapy↗

PubMed1990

Whole organ sectioning of mixed parotid tumors.

A pathologic study involving 15 standard formal parotidectomy specimens was carried out using the whole organ sectioning technique. Histopathologic characteristics noted included the presence of exposed capsule, breaks of the capsule, capsular incompleteness, tumor ingrowth and thickness, cellularity, and lymphocytic infiltration. Tracings of histopathology slides were used to reconstruct the three-dimensional configuration of each tumor as viewed from different angles. No tumor had a smooth surface. At the extreme, two tumor lumps were connected by just a narrow waist. Separated tumors were not seen. In only one specimen did a lymph node contain an additional tumor in the form of an adenolymphoma. All tumors showed some exposed capsule or "bare area" to a degree affected mainly by the position of the tumor. Capsular damage was occasionally seen and was usually minor. Capsular incompleteness and tumor ingrowth make global capsular dissection unsafe. It is concluded that formal parotidectomy remains the operation of choice for pleomorphic adenoma of the parotid gland, although capsular dissection (otherwise termed enucleation) cannot be entirely avoided during the procedure.

Adenoma, Pleomorphic↗

PubMed1990

Efficacy of radical neck dissection for the control of cervical metastasis after radiotherapy for nasopharyngeal carcinoma.

Fifty-one patients who had persistent or recurrent neck disease from nasopharyngeal carcinoma after radiotherapy underwent radical neck dissection. The follow-up period ranged from 0.5 to 9 years (median: 2 years). Multiple cervical lymph node involvement was present in 51% of the patients (26 of 51). Malignant cells were detected in 88% of the resected specimens (45 of 51). The clinical sign of fixation of lymph node is the only factor that affects the successful control of neck disease (p = 0.04). Extracapsular extension of the nodal disease was present, and 35% of the lymph nodes were adherent to surrounding structures at operation (18 of 51). There was one hospital mortality and the overall morbidity was minimal. The actuarial survival at 5 years was 38%, and the probability of control of neck disease was 66%. Radical neck dissection is effective in controlling post-irradiation cervical metastasis from nasopharyngeal carcinoma.

Adult↗

PubMed1990

Modified jet ventilation during total laryngectomy: a prospective study using pulse oximetry and a pressure regulator.

A method of jet ventilation during total laryngectomy is described. During the construction of the terminal tracheostomy, a small metal tube is used, instead of the traditional tracheostomy tube, to provide intermittent jet ventilation down the distal trachea. A pressure regulator is also employed to choose a driving pressure best suited to the chest and lung compliance of each patient. Excellent surgical access for tracheo-cutaneous anastomosis is achieved. Satisfactory ventilation during the jet period is also confirmed by unaltered PaCO2 and increased PaO2 levels. The use of pulse oximetry as a non-invasive and continuous monitor of arterial oxygenation is a simple alternative to arterial blood sampling.

Adult↗

PubMed1989

Fate of skin element of pectoralis major flap in intraoral reconstruction.

A skin island carried by pectoralis major muscle has been used to reconstruct an intraoral defect created after resection of a tumor. To our knowledge, what happens to the skin after its mobilization from the chest wall into the mouth has not been documented. To answer this, a wedge biopsy of the intraoral skin island on the pectoralis muscle was performed in 14 patients under local anesthesia. The skin biopsy specimen was subjected to scanning electron microscopic and histologic examination. The interval between the reconstructive surgery and the biopsy ranged from ten to 66 months (mean, 32 months). The results revealed desquamation of the epidermis and loss of appendages. The degree of desquamation was maximal when the skin island was used to replace the whole of the floor of the mouth and least when it was used for the lateral portion.

Adult↗

PubMed1989

Immediate reconstruction of pharyngoesophageal defects. Preference or reference.

In this era of development in reconstruction, interest in searching for the most appropriate procedure for replacing the pharyngoesophageal defect is intense. The type of defect, depending on the level of invasion by the cancer, should be classified as partial pharyngeal, circumferential pharyngeal, or pharyngoesophageal. Within each class, the surgeon can have his preference for a reconstructive procedure according to available expertise and familiarity. In our series of 97 patients with pharyngoesophageal defects resulting from resection of laryngeal, hypopharyngeal, and cervical esophageal cancers, the patch-on pectoralis major myocutaneous flap, the tubed pectoralis major myocutaneous flap, and the stomach were used for the three types of defects, respectively. Mortality and morbidity, while kept at an acceptable level, appear to rise as the complexity of the procedure increases. This supports the argument that the reconstructive method should be selected with reference to the type of defect, which is in turn dependent on the site and behavior of the tumor. The reconstructive procedure is to fit the defect, and not vice versa.

Adult↗

PubMed1989

Injury to the prepuce.

Injury to the prepuce is uncommon. A total of 32 patients were treated within a 3-year period. A difference in the aetiology between boys and adults was noted. Accidental injury to the prepuce occurred in 6 boys, with zipper injuries being the commonest among children. Coital and self-inflicted injuries accounted for 85% of adult cases. In patients with coital injuries, predisposing phimosis or a short frenulum was common.

Adolescent↗

PubMed1988

Tumor clearance at resection margins in total laryngectomy. A clinicopathologic study.

The specimens from total laryngectomy performed in 70 patients were studied using the step-serial whole organ sectioning technique. Transverse histologic sections were taken and examined for minimum tumor clearance. The clinical status of patients for at least 4 years of observation was correlated with microscopic clearance of margins. The actual presence of tumor at the margins of resection was found in 21 (30%) of the specimens. The tumor was found to reach within 1 mm, 2 mm, and more than 2 mm from the margins in nine (13%), four (6%), and 36 (51%) specimens, respectively. The anterolateral margin was most commonly involved (19%), followed by the posterolateral (11%), postcricoid (7%), and upper (1.4%) margins. Local recurrence was found to be related to degree of clearance as 10 of 21 (48%) patients with no clearance and one of nine (11%) with 1 mm clearance had local failure. None of the patients with 2 mm clearance or more developed local recurrence. It is concluded that step-serial whole organ sectioning is an adequate method for thoroughly examining resection margins in laryngectomy specimens.

Carcinoma, Squamous Cell↗

PubMed1988

Immediate tracheoesophageal puncture for voice restoration in laryngopharyngeal resection.

A 2-year prospective study on primary tracheoesophageal puncture was carried out to evaluate the morbidity of the procedure and its success in restoring speech. Fifty-two patients, 36 of whom suffered from carcinoma of the larynx and 16, carcinoma of the hypopharynx, were entered into the study. Thirty-three patients underwent total laryngectomy with primary pharyngeal closure, 14 patients had, in addition, pharyngectomy and pectoralis major myocutaneous flap reconstruction, and 5 patients had pharyngolaryngoesophagectomy and gastric transposition. Tracheoesophageal or tracheogastric speech was successful in 58, 86, and 80 percent, respectively. Manometric studies showed that the neopharyngeal sphincter pressure decreased in all instances, but a correlation between the neopharyngeal pressure and the success of tracheoesophageal speech was not demonstrable. The morbidity rate related to tracheoesophageal puncture was low. Therefore, we believe it to be a safe and feasible procedure that can facilitate early voice restoration.

Adult↗

PubMed1988

An evaluation of routine operative cholangiography.

The value of routine use of operative cholangiography was evaluated in 225 patients. In 65 patients (29%), there was one or more clinical or operative indications for common duct exploration and only 21 cases showed positive cholangiographic findings and were explored. There were four negative explorations in this group. In the remaining 160 patients who had no indication for common duct exploration, 157 had a normal cholangiogram and three had false positive cholangiographic findings and were explored unnecessarily. If operative cholangiography had been performed only on those patients with clinical or operative indications for common duct exploration, no ductal stone would have been missed. A selective use of operative cholangiography is advocated and the investigation should be restricted to those patients with clinical or operative indications for exploration of the common bile-duct.

Cholangiography↗

PubMed1988

Emergency endotracheal intubation under fiberoptic endoscopic guidance for malignant laryngeal obstruction.

Endotracheal intubation under fiberoptic flexible scope guidance is an easy technique to master and can be performed under local anesthesia. It provides immediate and safe intubation of malignant obstructive lesions of the larynx and allows surgical resection and reconstruction to be carried out as an emergency procedure. Ten patients with malignant obstructive lesion of the larynx were intubated and managed successfully in this manner. Refinements of intubation techniques under fiberoptic endoscopic guidance were described.

Aged↗

PubMed1988

Parapharyngeal inflammatory pseudotumor presenting as fever of unknown origin in a 3-year-old girl.

A parapharyngeal inflammatory pseudotumor in a 3-year-old girl who presented with high fever, anemia, and weight loss is described. The histologic differentiation from other fibroblastic lesions occurring in the head and neck region of a child is discussed. Symptoms improved dramatically after removal of the mass. The lesion may represent an exaggerated local response to an as yet unidentified agent with concomitant systemic manifestations.

Biopsy↗

PubMed1987

Regional chemotherapy through a saphenous vein graft for the treatment of head and neck cancers.

Regional chemotherapy was given through a vein grafted between the common carotid and external carotid arteries to 20 patients who had a variety of advanced head and neck cancers. The objective response rate was 73.6%, which included 36.8% complete response. The median duration of response was more than 10 months. The toxicity was mild and well tolerated. The complication rate associated with the procedure was low. This form of regional chemotherapy has significant advantages over the conventional form that uses drugs given through the retrograde temporal artery because the catheter-related complications are eliminated, the perfusion of the tumor can be maintained consistently, and, consequently, the response rate is high and the duration of response is increased.

Adult↗

PubMed1987

Avoiding stenosis in the tubed greater pectoral flap in pharyngeal repair.

Replacement of circumferential defects of the pharynx with skin-lined flaps rolled into a tube had the problem of anastomotic stricture formation. To prevent and correct stenosis at the mucocutaneous junction, an interdigitating anastomotic line produced by making vertical slits on the skin edge and the esophageal stump edge is used. It allows for maintenance of the lumen despite suture line contraction.

Aged↗