CT arteriography and venography in pulsatile tinnitus: preliminary results.

BACKGROUND AND PURPOSE: Pulsatile tinnitus (PT), a common disorder, can be caused by a variety of otologic and vascular lesions. Various imaging modalities, including CT, MR imaging and angiography, and conventional angiography, have been used in the assessment of PT. Ideally, a single imaging study to evaluate for the largest variety of etiologies would be optimal. In our study, we examine the potential for CT arteriography and venography (CTA/V) in the evaluation of PT. METHODS: Sixteen patients with PT were prospectively evaluated by an otolaryngologist, had a normal otologic examination, and were referred for a CTA/V. All examinations were performed on a 16-section multidetector CT. The carotid bifurcations, internal carotid artery course, transverse and sigmoid sinuses, jugular foramen, internal jugular vein, sella turcica, and temporal bones were evaluated. RESULTS: Seven of the 16 patients had lesions on CTA/V that could account for their PT. Examples of pathologic conditions in the series included a significantly dominant venous system, a venous diverticulum with stricture, and a transverse sinus stenosis. CONCLUSIONS: Preliminary findings indicate that CTA/V can be a valuable imaging tool in the assessment of PT. With this technique, arterial, venous, middle, and inner ear causes of PT can be excluded.

Prospective clinical trial of a human tumor cloning system.

A prospective clinical trial was performed to evaluate the usefulness of a human tumor cloning system for selecting single-agent chemotherapy for patients with advanced cancers. Six hundred four single-agent trials were performed in the 470 patients whose tumors were submitted for drug sensitivity testing. Only 246 of these 604 trials (41%) could be directed by the cloning system results because of inadequate tumor growth and other difficulties. In these 246 prospective trials, there was a 60% true positive and an 85% true negative rate for predicting for response or lack of response of an individual patient's tumor to the single agent. There was also a relationship between the percentage of decrease in survival of tumor colony-forming units and the probability of a clinical response of the patient's tumor to the same drug used in vivo. Despite these encouraging findings, work to improve tumor growth and additional prospective clinical trials of the system are needed before the system can be recommended for routine clinical use.

Computed tomographic evaluation of non-metallic middle-ear prostheses.

Non-metallic middle-ear prostheses, including a plastipore total ossicular replacement prosthesis (TORP) and partial ossicular replacement prosthesis (PORP), a Teflon loop stapes piston, and a Ceravital PORP were used to reconstruct the ossicular chain in formalin fixed cadaver temporal bones. The temporal bones were examined using high resolution, thin-section computed tomographic techniques identical to those used for patient studies. The detail and resolution of the images were comparable with those obtained on standard patient exams. The temporal bones were evaluated to determine the appearance of the prostheses in normal and abnormal positions within the middle ear. The radiologist examined the images without fore-knowledge of the position of the prostheses and was able to accurately identify both normal and abnormal positions. With the proper technique an accurate evaluation of non-metallic middle-ear prostheses is possible by high-resolution computed tomography.

Effects of neuronal activity on kainic acid neurotoxicity in the ventral cochlear nucleus.

Kainic acid was injected into the brain stem of adult guinea pigs, and the animals were either placed in a sound reducing-chamber or stimulated with 90 dB noise. The pattern and rate of kainic acid-induced degeneration in the anteroventral cochlear nucleus (AVCN) of sound-deprived animals was similar to that in animals exposed to ambient noise [2]. The amount of degeneration was greatly increased in animals stimulated with 90 dB noise. Therefore, although decreased activity in primary auditory fibers does not protect neurons in the AVCN from kainate-induced neurotoxicity, increased auditory stimulation augments the effects of kainic acid in the cochlear nucleus.

In vitro stem cell assay in head and neck squamous carcinoma.

Squamous cell carcinoma of the head and neck was successfully cultured from 33 to 73 specimens (45 percent) using the soft agar technique developed by Hamburger and Salmon. Successful cultures were evenly divided between biopsies of primary tumors and metastases; no growth and contaminated specimens predominantly came from biopsies of primary tumors. Prediction of viability before plating with trypan blue was unreliable. The cloning efficiencies in each histologic grade had a wide range, but the median cloning efficiency was higher for poorly differentiated tumors. Six of 11 patients with cloning efficiencies greater than 0.02 percent were dead of disease within 3 months, whereas only 1 of 16 patients with cloning efficiencies less than 0.02 percent was dead of disease at 3 months (p < 0.01). In vitro chemotherapeutic drug sensitivity testing correctly predicted in vivo resistance in three patients. The in vitro stem cell assay should prove a useful tool for clinical and biologic studies of head and neck cancer.

Cochlear damage and increased threshold in alpha-difluoromethylornithine (DFMO) treated guinea pigs.

Alpha-difluoromethylornithine (DFMO) inhibits polyamine synthesis and is used as an antineoplastic and antiparasitic drug. In early human trials DFMO unexpectedly caused a sensorineural hearing loss. In the current study DFMO was administered to guinea pigs to investigate its effects on organ of Corti histology and on auditory thresholds. Histologic examination revealed that DFMO caused greatest damage in the hook and first turn. Damage in the second and third turns was minimal. Animals treated for 12 weeks with DFMO differed significantly (P less than 0.05) from controls in the hook and first turn in that: 1) DFMO caused a loss of hair cells in all rows. Loss of inner hair cells was greater than that of outer hair cells. 2) The remaining outer hair cells were shorter and contained a greater number of Hensen bodies. 3) The Deiters' cell bodies were longer and this increased length was associated with the decreased length of the corresponding outer hair cells. Brainstem audiometry showed that DFMO produced a hearing loss and the magnitude of this loss increased over twelve weeks of DFMO administration.

Freeze-fracture of neurons in nucleus magnocellularis of the chick.

4- to 8-day-old chicks were used to examine the ultrastructure of end bulbs and neurons of nucleus magnocellularis by freeze-fracture and thin section techniques. Both normal animals and animals deafferented by removal of the basilar papilla were used to describe the pre- and postsynaptic membranes of these neurons. Postsynaptic membrane specializations similar to those described in rodents were found in normal and deafferented chicks. In the presynaptic end bulb there was an immediate cessation of endocytotic vesicle formation after deafferentation. There was also a shift in the preferential fracture plane from the presynaptic to postsynaptic membranes 48-72 h after basilar papilla removal. These results indicate that the ultrastructure of this synaptic complex is comparable to that seen in mammals.

The effects of DFMO on polyamine metabolism in the inner ear.

Difluoromethylornithine (DFMO) is a novel antineoplastic agent that was associated with an unexpected hearing loss in Phase II clinical trials. DFMO interferes with polyamine synthesis by inhibition of the enzyme ornithine decarboxylase (ODC). The objective of the current study was to establish a methodology to determine the effect of DFMO on polyamine levels and ODC activity in the cochlea. Guinea pigs received DFMO in their drinking water and were tested for auditory brainstem response threshold shifts. The organ of Corti, the lateral wall, and the acoustic nerve were assayed for both ODC activity and polyamine levels. In DFMO treated animals there was an inhibition of ODC activity in cochlear tissues as well as in intestinal mucosa. In addition, a significant depletion of cochlear polyamines was observed in the treatment animals. This study suggests that systemically administered DFMO inhibits ODC activity and interferes with polyamine synthesis in the cochlea.

Central nervous system changes associated with noise-induced hearing loss: an electron microscopic and freeze-fracture study of the chick nucleus magnocellularis.

This investigation assessed the effects of noise-induced hearing loss on the avian nucleus magnocellularis, the homologue of the mammalian cochlear nucleus. Fifteen-day-old chicks were exposed to high-intensity broad-band noise (132 dBA) for 24 to 72 hours. Hearing loss was documented with auditory brain-stem response recordings and scanning electron microscopy of the basilar papilla. Nucleus magnocellularis was assessed with thin-section electron microscopy and freeze-fracture techniques. Freeze-fracture preparations of noise-exposed animals showed a decrease in synaptic vesicle fusion sites at the synaptic active zone, a decrease in re-uptake of presynaptic membrane by coated vesicles, and a shift of the preferential fracture plane at the synapse from the presynaptic membrane to the post-synaptic membrane. These findings support the hypothesis that the effects of noise are not limited to the auditory periphery, but that transneuronal changes extend into the auditory central nervous system.

Endoscopic management of cerebrospinal fluid leaks and cephaloceles.

The excellent visualization and atraumatic surgical techniques of endoscopic sinus surgery have been applied to the management of five cerebrospinal fluid leaks and two nasal cephaloceles. In all cases, the exact site of the lesion was identified. Four cerebrospinal fluid leaks were grafted with a free or pedicled septal mucosal graft. The fifth cerebrospinal fluid leak came from a narrow sphenoethmoid recess and stopped after the mucosa was abraded. The two cephaloceles were reduced intranasally and covered with bone and mucosal grafts. Not all cases seen in the same time period were treated endoscopically; two additional cerebrospinal fluid leaks were treated with conventional techniques because of severe nasal inflammatory disease and intracranial complications. The technique and indications for endoscopic management of cerebrospinal fluid leaks and cephaloceles are discussed.

Group psychotherapy for head and neck cancer patients.

The diagnosis of cancer has a profound emotional effect on the patient. We report the two-year experience of a weekly support group attended by 142 hospitalized head and neck cancer patients and 33 family members. The major goal for the group was to provide an open forum for discussion of any problems that faced the patient. Group size was usually four to eight patients and two to four therapists. Weekly data sheets documented attendance and major themes for the group. The most common theme was anticipation of and reaction to treatment. Initial difficulties with the group included ambivalence by the professional staff, low attendance, and logistical problems. Subjective impressions of the staff were that the group improved patients' morale, patient to patient support, compliance, and decreased the rate of discharge against medical advice.

Repair of peripheral nerves of unequal diameters.

Four techniques for anastomosis were investigated for the anastomosis of a large proximal segment to a smaller distal segment of rat peripheral nerve with a size disparity of approximately 3 to 1. The techniques were perineural sutures (group I), KTP laser annealing (group II), collagen tubes with a 5-mm gap between the nerve segments (group III), and collagen tubes without a gap between the nerve ends (group IV). At 6 weeks there were no gross nerve distractions in groups I or IV. There were two failures in group II and three in group III. The percentage of fibers that crossed intact anastomoses were: group I, 89%; group II, 75%; group III, 115%; group IV, 125% (P less than .05 for the collagen tube repairs). Our results indicate that the suture technique is still the most reliable method of nerve repair. However, collagen tubes were effective in increasing the percentage of axons crossing the anastomosis.

Patency of the internal jugular vein after functional neck dissection.

The objective of this study was to determine the immediate patency rate for internal jugular veins preserved in functional neck dissections. Thirteen patients had contrast-enhanced CT scans 2 to 4 weeks postoperatively. Ten veins were patent and had a diameter comparable to that seen on the preoperative scan; one vein was narrowed but patent; two were occluded. Probable factors associated with occlusion include trauma of the vessel and extrinsic compression of the vein by the skin or myocutaneous flaps.

Acute management of laser-ignited intratracheal explosion.

The laser-ignited airway explosion is a shocking emergency. Techniques available for prevention of an airway fire minimize the risk, but they are not applicable in all circumstances. The severity of the patient's injury depends on the duration and intensity of the burn. Prompt, appropriate management is facilitated if the operating team has previously discussed and "rehearsed" this potential disaster. The distal airway burn produced by an ignited endotracheal tube differs from an inhalation burn in character and severity. The anatomic and respiratory effects occurring subsequent to the laser-induced burn are examined. Emergency care requires immediate elimination of the fire, removal of the tube and any foreign body or debris, and usually a tracheostomy. A program of medical and endoscopic management is suggested.

Endoscopic sinus surgery for mucoceles: a viable alternative.

Functional endoscopic surgery affords the potential for dramatically reducing operative morbidity of surgery for paranasal sinus mucoceles by offering a minimally invasive approach under local anesthesia. Following surgery, direct endoscopic visualization of the area enables accurate follow-up. Unlike sinus obliteration, the ability to accurately image the sinus by CT is also preserved. This paper presents our preliminary experience with 18 mucoceles in which endoscopic sinus surgery was attempted. Five patients had preoperative proptosis and diplopia, three had Pott's puffy tumor and five had erosion of the posterior table of the frontal sinus. Fifteen patients were satisfactorily treated endoscopically, two lesions could not be satisfactorily approached and required external surgery, and one patient had persistent disease. No disease recurrence has been noted to date with endoscopic follow-up of up to 42 months.

The effect of preoperative adriamycin and dihydroxyanthracenedione on wound healing.

Preoperative adjuvant chemotherapy is being used with increasing frequency in advanced head and neck cancer; however, the effects of chemotherapy on wound healing have not been fully elucidated. To evaluate the effect of preoperative chemotherapy, experimental animals were given chemotherapeutic drugs, wounded, and the subsequent wound breaking strength determined. Rats received a single dose of intravenous tumoricidal drugs (adriamycin or or dihydroxyanthracenedione) either one week before or simultaneously with wounding. Wound breaking strength of treated animals and control animals receiving no chemotherapy was measured one and two weeks after wounding. All wounds, regardless of treatment, were stronger at two weeks than at one week after wounding. Wound breaking strength was reduced at both times when chemotherapy was administered one week before wounding. Wound breaking strength in animals that were simultaneously wounded and received chemotherapy was similar to controls. Both adriamycin and dihydroxyanthracenedione have a deleterious effect on one parameter of wound healing--wound breaking strength--when administered one week before wounding.

Head and neck manifestations of uncommon infectious diseases.

Certain uncommon systemic infections may be present with head and neck manifestations either initially or during the course of the disease. A high index of suspicion is required on the part of the otolaryngologist with the subsequent procedures leading to the appropriate diagnosis. The manifestations of infectious diseases such as erysipelas, histoplasmosis, rabies, tetanus, botulism, and cysticercosis must be understood by the head and neck specialist. For successful management, many of the infections require prompt identification and initiation of therapy. Airway maintenance, ventilatory support, and medical chemotherapy may be required.

Success of the modified Epley maneuver in treating benign paroxysmal positional vertigo.

OBJECTIVE: Benign paroxysmal positional vertigo (BPPV) is a common condition seen by otolaryngologists. The purpose of this study is to determine the ability of the modified Epley maneuver to treat BPPV. STUDY DESIGN: Retrospective review. METHODS: A retrospective chart review of 107 patients diagnosed with BPPV at our institution between March of 1993 and June of 1995. Each patient was diagnosed with isolated BPPV by history and Hallpike-Dix maneuver. There were no other vestibular symptoms or electronystagmogram abnormalities. Patients diagnosed with BPPV received modified Epley maneuvers, were instructed to remain upright for 48 hours, and wore a soft collar for a week. Patients were followed up with repeat Hallpike-Dix maneuvers at 1 to 2 weeks. If symptoms persisted, the maneuver was repeated for up to a maximum of three times, at which point patients were considered to have failed treatment. RESULTS: The average age of patients was 57.8 years old. Thirty percent were male and the right ear was affected in 54%. The posterior semicircular canal was affected in 105 ears. The average patient received 1.23 Epley maneuvers, with a success rate of 93.4%. No successfully treated patients received mastoid vibration. Seven out of 107 patients failed after three Epley maneuvers. Two failure patients had a history of temporal bone fracture. Two failure patients were treated with posterior semicircular canal block surgery. CONCLUSION: The modified Epley maneuver is an excellent treatment for BPPV.

The versatile midface degloving approach.

The exposure obtained using the degloving approach is superb and the absence of resultant facial scar or deformity provides a dramatic new addition to the otolaryngologist's surgical repertoire. The advantages of the degloving technique in exposure of the midface, nasal cavities, paranasal sinuses, nasopharynx, skull base, and clivus have led to its increasing importance in the otolaryngology literature. Within 2 years of the technique's introduction in our department, it had been used 48 times for a wide variety of problems, including inverting papilloma, juvenile angiofibroma, chordoma and selected cases of fungal disease of the sinuses. This article describes the procedure, reports the results from a panel of 48 patients, and discusses potential complications. The authors' experience with this procedure indicates that it should become a procedure of choice for management of inverting papilloma and juvenile angiofibroma, as well as a major alternative method in many other circumstances.

3-D CT for cranial facial and laryngeal surgery.

Three-dimensional imaging is a new digital technology which interpolates two-dimensional computer tomography information to render a "life-like" anatomic display of the diagnostic information. We have found that this new methodology significantly improves the assessment and therapy of patients undergoing surgical procedures of the head and neck. The technique has been used in cranial-facial and laryngeal pathology, and in preoperative planning of tumor resection, particularly skull-base neoplasms. The use of three-dimensional computer tomography improves the display of the location and volume of pathology and affords accurate therapeutic and surgical planning. The choice and extent of surgery is better defined, and precise bone removal can be performed. In reconstructive surgery, an accurate prefabricated model of the bony defect can be made to aid reconstruction. Representative cases demonstrating the use of three-dimensional computer tomography in head and neck surgery, and its benefits in saving operative time and improving the postoperative result, will be discussed.