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C A Van Hasselt

Publications and source records attributed to C A Van Hasselt.

At least 19 recordsLinked to original sources
PubMed2005

[The immunohistochemical observations of NOS in the nasal mucosa of allergic rhinitis animal model of guinea pigs].

OBJECTIVE: To study the immunoreactivity and distribution of both iNOS and eNOS isoforms, and observe the effect of desloratadine on them. METHOD: The guinea pigs were sensitized and challenged followed by harvest of their nasal tissue for immunohistochemical staining. The slides images were semiquantitatively analyzed and compared with the desloratadine treated group and negative control group. RESULT: Both iNOS and eNOS were positively stained in each group. The immunoreactivity of iNOS had no significant difference between groups (P > 0.05), but eNOS had stronger immunoreactivity in the model group and the desloratadine treated group when compared with the negative control group (P < 0.01 and P < 0.05). In addition to the distribution area of iNOS, eNOS was also positive stained in the goblet cells. Desloratadine had no influence on iNOS and eNOS immunoreactivity. CONCLUSION: eNOS might play a more important role than iNOS in regulating the NO level of the nasal tissue of the guinea pigs suffered from allergic rhinitis, and desloratadine had no involvement in regulating the expression of iNOS and eNOS.

Animals↗
PubMed2005

[The effect of desloratadine on the TXB2 and leukotrienes levels in the nasal lavage fluid of allergic rhinitis animal model].

OBJECTIVE: To observe the thromboxane (TX)B2 and cysteinyl leukotrienes (LTs) levels in the nasal lavage fluid of allergic rhinitis model and to observe the effect of desloratadine on the mediators. METHOD: In the positive control group, 8-12 week old male or female guinea pigs were intranasal sensitized and challenged with ovalbumin solution. The antihistamine treatment group was treated with desloratadine and the negative control group was sham-sensitized and sham-challenged. The nasal lavage fluid of each group was collected 5 hours after challenge and the levels of TXB2 and LTs in the nasal lavage fluid were measured. RESULT: In the positive control group, the TXB2 and LTs levels were the highest of the three groups and the desloratadine treated group had lower level (P < 0.05 and P < 0.01). The negative control showed the lowest level. CONCLUSION: Our study demonstrated that in this model of allergic rhinitis, the levels of TXB2 and LTs in nasal lavage fluid increased dominantly after allergen challenge and desloratadine could inhibit the release of TXB2 and LTs, which implied that the therapeutic mechanism of desloratadine might contribute to the inhibitory effect on TXB2 and LTs production or release in allergic rhinitis subjects.

Animals↗
PubMed2002

A case of neonatal stridor.

A case is reported of a retropharyngeal abscess in a neonate who presented with increasing stridor since birth. Group B streptococcus was cultured from the abscess contents and the maternal birth tract.

Anti-Bacterial Agents↗
PubMed2001

Internal carotid artery hemorrhage after irradiation and osteoradionecrosis of the skull base.

OBJECTIVE: To evaluate the clinical presentation and management of internal carotid artery rupture after irradiation and osteoradionecrosis of the skull base. STUDY DESIGN AND SETTING: A retrospective review of the patients in an otorhinolaryngology-head and neck secondary and tertiary referral center. METHODOLOGY: From January 1993 to December 1996, patients with hemorrhage from internal carotid artery as a complication of irradiation and osteoradionecrosis of skull base were reviewed and analyzed. RESULTS: Four patients with internal carotid arterial rupture were included in this study. Angiography was performed in all cases. Embolization of the aneurysm was performed on 2 patients and the remaining 2 patients underwent occlusion of their internal carotid arteries. Three of the 4 patients did not survive. The fourth is currently alive and well 18 months after embolization of 1 internal carotid artery. CONCLUSION: Skull base osteoradionecrosis with bleeding from internal carotid artery is a potentially fatal complication of irradiation. Angiography was the mainstay of diagnosis with embolization of the aneurysm and embolization or ligation of the internal carotid artery being the management options. Internal carotid artery occlusion is the definitive treatment provided cross circulation is adequate. SIGNIFICANCE: The advantages and disadvantages of the treatment options are discussed and a management protocol is proposed.

Aged↗
PubMed2001

Excision of the preauricular sinus: a comparison of two surgical techniques.

OBJECTIVES: To compare the long-term recurrence rate of the standard technique (simple sinectomy) and the supra-auricular approach (wide local excision) for the surgical management of preauricular sinuses. STUDY DESIGN: Retrospective cohort. METHODS: Fifty-four patients with a preauricular sinus excised between May 1986 and December 1996 were included in this study. All patients were categorized into one of two groups based on the type of surgery performed: the standard technique or the supra-auricular approach. The medical records were then reviewed and the latest information concerning the recurrence of a preauricular sinus were updated by phone interview. The recurrence rate of these two groups was statistically analyzed by the Fisher exact test. RESULTS: Forty-nine of 54 patients were successfully contacted with data updated and analyzed. The 32% recurrence rate of the standard excision (n = 25) was significantly higher than the 3.7% recurrence rate of the supraauricular approach (n = 27; two-tailed test, P = .01). CONCLUSION: The supra-auricular approach for excision of a preauricular sinus has a statistically lower recurrence rate in comparison to the standard technique.

Abscess↗
PubMed1997

Auditory brainstem responses after radiotherapy for nasopharyngeal carcinoma.

The effect of irradiation for nasopharyngeal carcinoma on auditory brainstem responses and hearing was investigated in 19 otologically normal patients undergoing standard fractionated megavoltage radiotherapy. Auditory brainstem responses and pure tone audiometry were performed before radiotherapy, and at 3 and 12 months after completion of radiotherapy. There were no significant changes in the wave I-III and III-V interpeak intervals, or in sensorineural hearing thresholds (bone conduction at 4 kHz and average of bone conduction at 0.5, 1, 2 and 4 kHz), after radiotherapy. In contrast to previous studies, we found no evoked potential evidence of subclinical brainstem damage arising from irradiation for nasopharyngeal carcinoma.

Adult↗
PubMed1996

Another CT sign of sinonasal polyposis: truncation of the bony middle turbinate.

In order to study the features of sinonasal polyposis (SNP) on CT, 100 consecutive coronal sinus CT examinations done for chronic inflammatory sinonasal disease were reviewed. The CT findings of the 27 fully documented SNPs were analyzed. All our SNPs were bilateral. There was a strong tendency for extensive involvement. Nasal polyps were seen in 22 of 27(81%); bony trabecular deossification in 23 of 27 (85%); widening of infundibulum in 26 of 27 (96%). We discovered a new sign "truncation of the bony middle turbinate", where the bulbous part of bony middle turbinate was missing, in 15 of 26 (58%) of SNP patients without a previous history of middle turbinectomy, 12 of 15(80%) were bilateral. The one SNP patient (1 of 27) with previous middle turbinectomy was not regarded to be real truncation. Truncation of the bony middle turbinate is a characteristic and easily recognizable ancillary sign, and is not seen in other patterns of sinusitis. Together with other features on coronal sinus CT, this adds diagnostic confidence in diagnosing sinonasal polyposis.

Adolescent↗
PubMed1995

The Hong Kong vascularized temporalis fascia flaps for optimal, mastoid cavity reconstruction.

The classical modified radical mastoidectomy offers the advantages of combining the mastoid cavity, the attic and the external canal into one cavity that remains open for inspection. However the ultimate goal to predictably produce well healed, dry and safe mastoid cavities despite receiving much attention has not been fulfilled. By employing basic surgical principles of wide access to facilitate meticulous removal of all cholesteatoma and then eliminating all raw surfaces of the bony cavity with pedicled vascularized deep temporalis fascia, the Hong Kong Flap technique achieves the highest percentage of dry, stable, disease free ears. This living fibrous tissue layer provides the optimal substrate for epithelial resurfacing while separating the mucosa and bone of the middle ear and mastoid from the surface epithelium. Excellent healing even under unfavourable circumstances is ensured by the rich blood supply to the pedicled temporalis fascia flap. Furthermore the technique obviates the need for second look procedures in more than two-thirds of cases as the cavity lining becomes transparent and simple observation is safe. The Hong Kong Flap was used to reconstruct 107 cavities between October 1988 and October 1992. 86 were performed for primary cholesteatoma removal and 21 for revision of discharging cavities. 103 (96%) healed soundly. There were 4 dry perforations. Minor complications occurred in 8 (7%) patients. 84 (78%) required n+o second exploratory operation. This is a straight forward procedure requiring no special technical skills. The concept is rational and provides the ideal management for cholesteatoma by achieving a dry, safe ear with one operation.

Cholesteatoma, Middle Ear↗
PubMed1994

Ultrasound imaging in laryngeal cancer: a preliminary study.

High resolution ultrasound is a promising technique in the assessment of laryngeal carcinoma, yet few published studies have appeared concerning its use. We set out to assess if ultrasound could correctly identify the site and size of known lesions, if unsuspected extralaryngeal spread or nodal involvement could be shown and if the results could be used to influence patient management. Fourteen patients with advanced laryngeal cancer (Stage T2 or above) were prospectively evaluated by systematic ultrasound technique, with the sonologist blind to the clinical findings. The results were correlated with clinical assessment and with histopathological findings in six patients who subsequently underwent surgery. Eleven of 14 tumours were visible on ultrasound and the site and size correctly identified in each. Unsuspected extralaryngeal spread was found in four cases increasing the tumour stage to T4; spread to the pre-epiglottic space was also shown in four cases. Nodal staging was correctly raised in two cases and incorrectly in one. Patient management was significantly influenced in 8/14 cases. Ultrasound can identify the majority of laryngeal tumours of Stage T2 and above, and detect extralaryngeal spread. Small tumours may not be visible but in this preliminary study, ultrasound complemented the clinical assessment and was useful in patient management.

Aged↗
PubMed1994

The 578-nm copper vapor laser in the treatment of cavernous hemangiomas in the oral cavity.

A variety of operative and nonoperative treatment methods have been proposed to deal with cavernous hemangiomas. In an otorhinolaryngological unit where experience has been gained from managing superficial vascular lesions in Chinese skin with the 578-nm copper vapor laser, three patients with symptomatic large mucosal hemangiomas in the oral cavity were treated. All lesions have shown significant shrinkage after a single treatment utilizing an energy level of 20 J/cm 2. No further treatment, surgical or laser, has been necessary after follow-up of at least 12 months. The unique biological and tissue interaction of the copper vapor laser light is believed to be responsible for this remarkable response.

Adult↗
PubMed1992

The lateral neck radiograph in suspected impacted fish bones--does it have a role?

A double blind trial, using lateral neck radiographs of 100 patients with proven impacted fish bones and 100 normal cases, was conducted to assess the sensitivity, specificity and positive predictive value of radiography for impacted fish bones. Values of 25.3%, 86.3% and 72.7% respectively were obtained. The results are correlated to the clinical findings and reasons for the poor performance of radiography are discussed. It is recommended that routine radiography for suspected impacted fish bones should be abandoned.

Esophagus↗
PubMed1992

Comparison of plain radiographs and computed tomographic scanning in nasopharyngeal carcinoma.

Plain radiographs, computed tomographic (CT) scans and clinical records of 100 patients with nasopharyngeal carcinoma were studied. CT scans and plain radiographs provided similar information in 46 patients. There were 54 cases in which the two techniques disagreed. In 45 cases CT demonstrated abnormalities not seen in plain radiographs and in nine cases plain radiographs demonstrated abnormalities not seen with CT scanning. Based on the total information gained from clinical examination, the imaging investigations, biopsies, and subsequent clinical course and investigations it appeared that none of the abnormalities predicted by plain radiographs alone could be substantiated. Conversely the CT abnormalities could be supported as being correct. We conclude that CT alone is the undoubted investigation of choice where this is available. Plain films provide less information, are unreliable and, where CT is available, superfluous.

Bone and Bones↗
PubMed1992

Flexible nasopharyngoscopy for fish bone removal from the pharynx.

The use of flexible nasopharyngoscopy with biopsy forceps for the removal of fish bones found in the oropharynx and hypopharynx is described. One hundred and sixty-eight patients with ingested fish bones in the upper aero-digestive tract were studied over a 12-month period. Of these, 73 per cent were removed per-orally, or by indirect laryngoscopy. Fifteen per cent were removed using the fibreoptic nasopharyngoscope. Twelve per cent required a general anaesthetic and rigid oesophagoscopy for removal of fish bones at or below the level of the cricopharyngeus muscle. The technique has proven to be quick, well tolerated and low in morbidity. It is invaluable in patients in whom indirect laryngoscopy is unsatisfactory.

Endoscopes↗
PubMed1992

Tuberculosis of the nasopharynx: clinicopathological features.

The clinicopathological features of 10 adult patients with nasopharyngeal tuberculosis (TB) are presented. 9 patients had no evidence of chest or systemic disease. 7 patients presented with cervical lymphadenopathy, and only 4 had nasal symptoms. Examination of the nasopharynx showed no abnormality in 2 patients, lymphoid hyperplasia in 4 patients, and a tumour-like mass in 4 patients. These findings suggest that nasopharyngeal TB may occur more frequently as part of an isolated upper respiratory tract infection than as secondary to pulmonary infection. The nasopharynx may be a portal of entry for tubercle bacilli in patients who develop cervical lymphadenitis. Involvement of the nasopharynx by TB may be underdiagnosed because it does not produce obvious symptoms or physical signs in all cases.

Adult↗
PubMed1992

Lugol's iodine dye-enhanced endoscopy in patients with cancer of the oesophagus and head and neck.

Lugol's iodine dye indicates the presence of unsuspected early oesophageal cancers during endoscopy at which such cancers fail to show the characteristic black colour change. We evaluated Lugol's iodine dye-enhanced endoscopy in 17 patients with oesophageal cancer. In a further 37 patients with head and neck cancer we examined the use of Lugol's iodine since these patients have a 29% risk of synchronous oesophageal cancer. The oesophagus was sprayed with Lugol's iodine (1.5%) during endoscopy. Any areas not turning black were biopsied. In 13 patients with oesophageal cancer discrete areas beyond the macroscopically obvious primary tumour showed no change in colour. Biopsy revealed cancer in all cases. Six synchronous cancers were found in the head and neck group, one of which was identified only by the use of Lugol's iodine. Lugol's iodine augmented the information gained about the oesophageal mucosa during endoscopy. It revealed unsuspected cancer which altered the management of patients with primary oesophageal cancer as well as those with head and neck cancer. We recommend the routine use of Lugol's iodine-enhanced endoscopy for surveillance of all 'at risk' oesophageal cases.

Adult↗
PubMed1992

The hazards of button batteries in the nose.

Foreign bodies in the nose are commonly encountered in ORL practice. Miniature button battery impaction in the nose has rarely been reported. Seven such cases have been encountered, each suffering complications directly attributable to the button battery. The complications included septal burns in five patients leading to septal perforation in one child, one case of severe nasal bleeding and one case of necrosis of the lateral nasal wall. The site of maximal damage corresponded with the negative pole of the battery in every case. The possible explanation for this and mechanisms of cellular injury are proposed. This paper underlines the potential hazards of button batteries as foreign bodies in the nose and emphasizes the need for rapid removal and long-term follow-up of these patients.

Child, Preschool↗
PubMed1991

Staging abdominal ultrasonography in nasopharyngeal carcinoma.

Abdominal ultrasonograms were performed on 81 unselected patients with newly-diagnosed nasopharyngeal carcinoma without clinical evidence of distant metastases. Two patients had ultrasonographic features suspicious of, but not diagnostic of, hepatic metastases. One of these two patients developed hepatic metastases six months after the examination while the other was free of metastases at follow-up 33 months afterwards. Of the 79 patients without evidence of metastases on ultrasonogram, two developed hepatic metastases after 22 and 32 months. Based on these results, we do not recommend abdominal ultrasonography as a routine staging investigation for nasopharyngeal carcinoma.

Carcinoma↗