[99mTc]-Bis-Methionine-DTPA Single-Photon Emission Computed Tomography Impacting Glioma Management: A Sensitive Indicator for Postsurgical/Chemoradiotherapy Response Assessment.

Background: The present study evaluated the prognostic value of [99mTc]MDM (bis-methionine-DTPA) follow-up single-photon emission computed tomography (SPECT) imaging for response assessment to chemoradiotherapy in glioma postoperatively. Materials and Methods: One hundred fourteen glioma patients (80 M:34 F) were followed postoperatively by sequential [99mTc]MDM SPECT, dynamic susceptibility contrast-enhanced (DSCE)-MRI, and magnetic resonance spectroscopy (MRS) at baseline, 6, 12, and 22.5 months postchemoradiotherapy. The quantitative imaging results and the clinical outcome were used for response assessment and for the final diagnosis. The quantitative parameter of [99mTc]MDM SPECT were also used for survival analysis. Results: A significantly (p = 0.001) lower target to nontarget (T/NT) ratio was observed in responders than in nonresponders. The sensitivity and specificity of [99mTc]MDM-SPECT for identifying tumor recurrence from radiation necrosis at a cutoff ratio of 1.90 were estimated at 97.9% and 92%. Whereas, the sensitivity and specificity of DSCE-MRI with the normalized cerebral blood volume (nCBV) cutoff of 3.32 for this differentiation was found to be 84.6% and 93.0%. MRS intensity ratios of Cho/NAA and Cho/Cr provided comparatively lower sensitivity of 81.0% and 85.3% and specificity of 73.0% and 73.7%. T/NT ratios correlated with nCBV (r = 0.775, p < 0.001) and to a moderate extent with Cho/NAA ratios (r = 0.467, p = 0.001). [99mTc]MDM SPECT and DSCE-MRI provided comparable results for predicting response assessment to chemoradiotherapy. There was a final diagnosis in 72 patients, of which 47 cases were tumor recurrence and 25 were radiation necrosis. The Kaplan-Meier analysis indicated that patients with T/NT ratio <1.9 showed prolonged survival (53.8 months) as compared (37.2 months) with those who demonstrated T/NT ratio >1.9 (p = 0.0001). Conclusion: Thus, this low-cost SPECT technique in combination with DSCE-MRI can be used accurately for mapping the disease activity, response assessment, and survival in glioma. [99mTc]MDM SPECT and DSCE-MRI had the same diagnostic efficacy to detect recurrent/residual tumor and radiation necrosis while MRS was inferior to both the techniques.

Singer's dystonia: first report of a variant of spasmodic dysphonia.

OBJECTIVES: We discuss the phonatory characteristics of a previously undescribed focal laryngeal dystonia present in the singing voice. METHODS: We performed a retrospective chart review of 5 patients with singer's dystonia at a neurolaryngology referral center. RESULTS: Four patients reviewed demonstrated phonatory characteristics consistent with adductor spasmodic dysphonia present in their singing voice. One patient demonstrated abductor spasmodic dysphonia in the singing voice. Each patient initially exhibited normal connected speech in conversational voicing. The treatment protocol and outcome are discussed, including the use of botulinum toxin. CONCLUSIONS: Singer's dystonia is a previously undescribed neurologic disorder that should be understood by those who treat voice performers and voice disorders.

Dose response of topical anesthetic on laryngeal neuromuscular electrical transmission.

OBJECTIVES: Our purpose was to determine the effect of a dose response to decreasing concentrations of topical anesthetic upon laryngeal neuromuscular electrical transmission. METHODS: We performed a prospective study at a neurolaryngology referral center. Forty-three patients were divided into 5 groups. Each patient underwent laryngeal electromyography (EMG) of a thyroarytenoid muscle before and 60 seconds after topical laryngotracheal lidocaine hydrochloride, normal saline solution, or nothing was applied. The pretreatment and posttreatment measurements were recorded with the same indwelling EMG electrode. Group 1 (n = 12) received 4% lidocaine, group 2 (n = 9) received 2% lidocaine, and group 3 (n = 8) received 1% lidocaine. Group 4 (n = 5) received topical normal saline solution instead of lidocaine. A fifth group (group 5, n = 9) had 2 EMG recordings measured, each separated by 60 seconds, without topical anesthetic. RESULTS: Groups 1, 2, and 3 showed significant decreases in the maximum peak-to-peak amplitude of the EMG recording (48.5%, 49.7%, 44.7%, respectively). Groups 4 and 5 failed to show a significant change in peak-to-peak amplitude after 60 seconds. There was no dose response change in EMG with decreasing lidocaine concentrations. CONCLUSIONS: All concentrations of lidocaine administered in this study decreased the laryngeal neuromuscular electrical transmission as measured by laryngeal EMG. This group of patients did not exhibit any dose response to anesthetic concentration. This finding is clinically significant for both diagnostic and therapeutic uses of laryngeal EMG preceded by administration of topical anesthetic.

Allergic reaction to ortho-phthalaldehyde following flexible laryngoscopy.

Flexible laryngoscopes are common outpatient surveillance tools. Cleansing of these scopes between patients must be quick, effective, and safe. One sterilant that largely meets these criteria is ortho-phthalaldehyde (OPA); however, infrequently, patients may develop allergic reactions to it. We present three cases of patients who developed significant allergic reactions following repeated laryngoscopic examinations. Subsequent intradermal allergy testing confirmed sensitivity to OPA. In addition, we reviewed the current literature, which includes 17 similar reactions reported in nine patients across disciplines. Allergic reaction to OPA is uncommon, but a potentially under-reported severe complication of repeated endoscopy.

Complete laryngotracheoesophageal cleft: complicated management issues.

OBJECTIVES/HYPOTHESIS: Laryngotracheoesophageal clefts are rare developmental anomalies of the upper aerodigestive tract. They range in severity from being virtually asymptomatic throughout life (type I) to being incompatible with life (type IV). The timing of diagnosis is crucial to the successful treatment of severe clefts. Treatment is complicated and requires a multi-team approach. The case report discusses the elements involved in diagnosing and treating this severe airway anomaly. STUDY DESIGN: Case report. METHODS: Review of a case at a tertiary care center. RESULTS: A case of a complete laryngotracheoesophageal cleft with left-side pulmonary agenesis in a newborn is reported. Rigid bronchoscopy revealed a common tracheoesophageal lumen from the larynx to the stomach with a single bronchus supplying the right-side lung. Management of this patient included establishment and maintenance of a tenuous airway, maintenance of nutrition, and anesthetic and surgical planning for upper aerodigestive tract reconstruction. CONCLUSIONS: Although severe laryngotracheoesophageal clefts are rare, they require prompt, team-oriented management for the best outcome possible. The diagnosis, sustenance, and treatment options of these patients depend on varied and complicated factors, which are discussed.