The cricothyroid space: topography and clinical implications

The inferior border of the thyroid cartilage and the superior rim of the cricoid arch are connected by the cricothyroid membrane and partly covered by the cricothyroid muscles ventrally. This region has been termed the cricothyroid space (CS) and is important with regard to surgical procedures, the spread of laryngeal cancer and traumatic lesions of the larynx. The precise topographic relations of the CS were investigated in plastinated serial sections of 21 normal adult human specimens. The CS consists of a caudal and a cranial portion, which are different with regard to their cartilaginous framework and their relationship to intralaryngeal structures. The caudal portion is bordered by the cricoid cartilage and reveals a complete separation of extra- and intralaryngeal regions by the cricothyroid membrane. It provides an easy access to the subglottic airways. The cranial portion of the CS is mainly bordered by the thyroid cartilage. It is characterized by a gap lateral to the median cricothyroid ligament. This allows a connection of extra- and intralaryngeal adipose tissue. There, extralaryngeal extension of laryngeal cancer preferentially occurs. Traumatic subglottic ruptures of the larynx involve both the caudal and cranial portions of the CS, which often results in extensive scar tissue formation.     

Functional differences between the two bellies of the cricothyroid muscle

The contraction of the cricothyroid (CT) muscle, which results in a decrease in the distance between the thyroid and cricoid cartilages, is considered to be the main factor in lengthening the vocal folds. This is achieved by rotation of the CT joint. The CT muscle is composed of two distinct bellies, the pars recta and the pars obliqua. The function of each subunit is not clearly understood, although it is believed that they act differently because their fibers run in different directions. To clarify the function of the two bellies in phonation, the fundamental frequency (F0), vocal intensity, subglottic pressure, vocal fold length, and CT distance were measured using an in vivo canine laryngeal model. On the basis of these measurements, we demonstrated that the two bellies are varied in their effect on raising the pitch, rotation, and forward translation of the CT joint. The stimulation of the pars recta nerve resulted in a greater increase in the F0 value compared with that of pars obliqua. The combined activity of the pars recta and pars obliqua is important in adjustment of the vocal fold length. The CT approximations directed parallel to the pars recta and pars obliqua simultaneously were more effective in elevation of the pitch than the approximation placed parallel to the pars recta only. This finding may be clinically significant with regard to CT approximation thyroplasty in human trails.     

Unilateral acro-keratoelastoidosis

INTRODUCTION: Acrokeratoelastoidosis was first described by O. Costa in 1953. We report a new case with a unilateral localization. CASE REPORT: A 27-year-old woman had atypical acrokeratoelastoidosis lesions of the right hand and foot since adolescence. Diagnosis was confirmed by histology. DISCUSSION: Several cases of acrokeratoelastoidosis have been reported in the literature, but this case is novel because of the unilateral localization. We recall the characteristic features of this disease and emphasize the heterogeneous nature of the manifestations. Differential diagnosis is discussed for this disease which is one of the group of acral lenticular keratoses.     

Synchronous glottic granular cell tumor and subglottic spindle cell carcinoma

We report the clinicopathologic findings in a case of coexistent glottic granular cell tumor and subglottic spindle cell carcinoma. There is no evidence in this case that suggests malignant transition of the granular cell tumor to malignant tumor. To our knowledge, this is the first report of synchronous granular cell tumor and subglottic spindle cell carcinoma.     

Unilateral cerebellar aplasia

Thirty physicians who immigrated together from South America to Israel were followed during their first two years in Israel. Success in the medical requalifying examination and finding work as physicians correlated directly with permanency in Israel, and, inversely, returning to country of origin was associated with being unqualified and unemployed. Age, sex, marital status, religion and previous professional status were not associated with permanency in Israel.     

Endoscopic laser excisional biopsy for selected glottic carcinomas

From January 1988 to December 1990, 44 previously untreated patients with squamous cell carcinomas (SCCs) of the true vocal cord (33 T1a, 11 Tis) underwent carbon dioxide laser excision. The mean follow-up was 28 months (range, 12 to 44 months). Endoscopic excisional biopsy was the primary treatment in 38 of the 44 patients, whereas postoperative radiotherapy was added in 6 cases in which the pathology report showed positive margins. Recurrent vocal cord SCC developed in 8 (18%) of the cases, with an average interval of 17.8 months. Re-treatment consisted of a second laser excision in 4 cases, radiotherapy in 1, hemilaryngectomy in 1, and total laryngectomy in 2. The definitive cure rate with endoscopic excisional biopsy for the patients originally treated with laser excision alone was 94.7% (36/38). Endoscopic laser treatment for selected glottic SCC proves to be an excellent alternative to radiotherapy or open neck surgery.     

Unilateral parathyroid exploration

Unilateral neck exploration (UNE) for primary hyperparathyroidism can be done with the same excellent results as bilateral neck exploration (BNE) with decreased operative time and postoperative complications with a good preoperative localization study. One hundred six charts were reviewed retrospectively in patients operated on between May 1989 and October 1996 with primary hyperparathyroidism. Seventy-seven of these patients had preoperative ultrasounds (US) performed by a radiologist interested in parathyroid ultrasonography. UNE was performed if the operative findings were consistent with the US and a normal gland was identified on the same side. If a normal gland was not identified on the initial side or there was a question of hyperplasia a BNE was performed. Forty-six of the 77 patients had UNE, and 31 had BNE. Sixty-nine of these patients were found to have accurate US. Based on these results there is a 90 per cent accuracy rate for US performed by an interested radiologist. Comparing operative times between patients with UNE and BNE, there was a statistical difference (P = 0.001). Complications were also recorded in each group. Patients with UNE had a 22 per cent complication rate, whereas patients with BNE had a 45 per cent complication rate. This difference was statistically significant (P = 0.04) (Fisher's exact test). The majority of complications were asymptomatic and symptomatic hypocalcemia. Two patients in the BNE group experienced transient hoarseness. The advantages of UNE include reduced morbidity, decreased operative time and avoidance of scarring in the contralateral neck. In the total study population (n = 106), 99 patients (93.4%) had a single adenoma. An accurate, noninvasive, low-cost preoperative localization study is necessary to practice UNE for primary hyperparathyroidism. Parathyroid US, done by an interested radiologist, with a 90 per cent accuracy rate, meets all these criteria.     

Techniques of management of subglottic stenoses with glottic and supraglottic problems

Glottic problems complicating a subjacent tracheal or subglottic stenosis may result from various causes, such as glottic closure due to fixation or paralysis of vocal cords, fibrous stenosing scars of the glottis, or instability of arytenoid cartilages. Resecting scar tissues, molding the closed glottis, and stenting a patent laryngeal lumen until consolidation are the basic means which, when associated in selected indications, allow recovery of respiration and speech through the normal routes.     

Late local recurrence after radiotherapy for tongue and early glottic carcinoma

BACKGROUND/AIM: Late local recurrence after radiotherapy for tongue and early glottic carcinoma is rarely discussed. In the head and neck cancer, approximately 90% of local recurrence occurred within 2 years after radiotherapy. However, we found that late local recurrence after radiotherapy for glottic cancer was not rare. Our aim was to evaluate the late local recurrence after radiotherapy for early glottic and tongue cancer. PATIENTS AND METHODS: From 1967 through 1982, 633 patients with tongue carcinoma and 330 patients with early (T1T2N0) glottic carcinomas were treated at the Department of Radiology, Osaka University Hospital. Of these 821 patients, 329 patients with tongue carcinoma and 221 patients with early glottic carcinoma survived at 5 years after radiotherapy without local recurrence. For tongue carcinoma, patients were divided by T category. For early glottic carcinoma, patients were divided by the tumor response at 40 Gy. RESULTS: Late local recurrence occurred in 23 of 329 patients (7%) with tongue carcinoma, and in 9 of 221 (4%) with early glottic carcinoma. For tongue carcinoma, late recurrence occurred in 19 of 249 patients (8%) in stage I and II, and 4 of 80 patients (5%) in stage III and IV. For glottic carcinoma, late recurrence occurred in 8 of 137 patients (6%) with tumor clearance at 40 Gy and 1 of 63 patients (2%) with tumor persistence at 40 Gy. The incidence of double cancer was also evaluated. Of 329 5-year survivors with tongue carcinoma, 39 patients (12%) had another malignancy, and 26 patients of 221 5-year survivors with early glottic carcinoma (12%) had also another malignancy. Of 39 double primaries of tongue carcinoma, 10 patients (26%) had head and neck malignancies, and none of 26 double primaries of early glottic carcinoma. CONCLUSION: Late local recurrence was not rare in tongue and early glottic cancer. Poor prognostic group showed lower incidence of late recurrence than good prognostic group. This result suggests that secondary tumor at the same site of primary tumor is late local recurrence.     

The effect of muscle relaxants on cricothyroid muscle: a report of three cases

PURPOSE: To determine the frequency of the computed tomographic (CT) pattern of nonaneurysmal perimesencephalic subarachnoid hemorrhage in the setting of ruptured posterior fossa aneurysms. MATERIALS AND METHODS: Four neuroradiologists independently and retrospectively reviewed cranial CT scans of 169 patients with ruptured vertebrobasilar aneurysms (44 cases of posteroinferior cerebellar artery aneurysm, 20 cases of superior cerebellar artery aneurysm, and 105 cases of basilar-tip aneurysm). RESULTS: The mean frequency of nonaneurysmal perimesencephalic pattern of subarachnoid hemorrhage in ruptured vertebrobasilar aneurysms was 7.1% (48 of 676 readings) among the four readers. The mean frequency of aneurysms with the pattern of hemorrhage for each location was as follows: basilar tip, 9.8% (41 of 420 readings); superior cerebellar artery, 5.0% (four of 80 readings); and posteroinferior cerebellar artery, 0%. In 75% (six of eight) of the cases in which the CT pattern of hemorrhage was deemed compatible by all readers with nonaneurysmal hemorrhage, the clinical presentation was mild. CONCLUSION: Because ruptured posterior fossa aneurysms manifest with the nonaneurysmal pattern of hemorrhage in approximately 10% of cases, a high degree of suspicion should be maintained even if the pattern of subarachnoid hemorrhage suggests a nonaneurysmal origin and clinical symptoms are mild.     

Unilateral and segmental localised polycystic kidney disease

Glomerulocystic disease (GCD) is a very rare condition. Only two previous reports have linked this condition with hepatoblastoma. We report a neonate with US evidence of grossly enlarged echogenic kidneys and features typical of hepatic fibrosis, complicated by the presence of a hepatoblastoma. The report discusses the differential diagnosis and highlights GCD as one cause of large, bright kidneys on US. It also adds further evidence to the suggested association between GCD and hepatoblastoma.     

The glottic aperture seal airway: a new ventilatory device

BACKGROUND: None of the presently used airway devices are ideal regarding ease of insertion, alignment with the laryngeal inlet, and provision of a high-pressure seal from the environment. The purpose of this study was to determine, in awake volunteers, the performance of a new ventilatory device, the glottic aperture seal airway, regarding ease of insertion, alignment with the laryngeal inlet, and forced exhalation seal pressure (PFES). METHODS: The glottic aperture seal airway consists of a curved tubular component that ends in the middle of an elliptical foam cushion glottic component. The posterior surface of the foam has a curved flexible plastic backing, which imparts a 60 degree angle between the proximal half and the distal half of the foam cushion. When the glottic aperture seal airway is properly in situ in a supine patient, the proximal half of the foam cushion is opposite the laryngeal inlet. The posterior surface of the plastic backing has a balloon attached to it. Inflation of the balloon presses the ventilation hole and foam cushion up against the laryngeal inlet, thereby creating a seal from the environment. Using the laryngeal mask airway as a control device, the glottic aperture seal airway was tested for time and ease of insertion, fiberoptic alignment with the laryngeal inlet, and PFES in 18 lightly sedated and locally anesthetized volunteers. RESULTS: The glottic aperture seal and laryngeal mask airways were inserted with equal ease and speed. The fiberoptic alignment with the larynx was excellent for both the glottic aperture seal and laryngeal mask airways. In all volunteers, the mean +/- SD PFES values at 0-, 10-, 20-, 30-, and 40-ml balloon inflation volumes of the glottic aperture seal airway were 23.4 +/- 11.8, 29.6 +/- 12.4, 42.7 +/- 12.5, 56.9 +/- 5.6, and 60 +/- 0 cm H2O, respectively; the PFES at > or = 20 ml balloon inflation volume of the glottic aperture seal airway was significantly greater than with the laryngeal mask airway (19.4 +/- 6.7 cm H2O, P < 0.01). A PFES of > or =60 cm H2O was achieved with the glottic aperture seal airway in all volunteers (n = 2 at 10 ml, n = 3 at 20 ml, n = 9 at 30 ml, and n = 4 at 40 ml). The glottic aperture seal airway did not cause any trauma. CONCLUSION: In awake volunteers, the glottic aperture seal and laryngeal mask airways were equally easy to insert and position. The glottic aperture seal airway was capable of achieving a higher PFES than the laryngeal mask airway.     

Unilateral galactocele following augmentation mammoplasty

Subchronic oral exposure to styrene in rodents (25 or 50 mg/kg/day in mice; 160 or 320 mg/kg/day in rats and guinea pigs, 5 days/week) for 4 weeks resulted in moderate congestion of pancreatic lobules, focal inflammatory reactions around islets (in mice) and altered serum insulin level while blood glucose levels remained unaffected. Increased beta cell degranulation together with characteristic neoformation of islets were predominantly seen in pancreas of guinea pigs.     

Unilateral retinitis pigmentosa sine pigmento

Surgical operation on 30 kidneys was carried out for branched renal calculi, with no operative mortality. Of 23 kidneys in which conservative surgical procedures were used, 83 percent are now stone-free. When all stones were successfully removed, cultures of urine were sterile in 80 percent of cases, but when fragments remained, no patient was infection-free. It was found that impaired renal function need not be a contraindication to surgical operation, and indeed that in five of seven patients with impaired renal function, serum creatinine levels either remained stable or improved. We believe that surgical removal is the most conservative management of branched renal calculi.