Objective: To analyze the changes in electroencephalography (EEG) during tilt table study in syncope and other orthostatic syndromes. Background: Tilt table testing is routinely performed for evaluation of unexplained syncope.... more
Objective: To analyze the changes in electroencephalography (EEG) during tilt table study in syncope and other orthostatic syndromes. Background: Tilt table testing is routinely performed for evaluation of unexplained syncope. Occasionally convulsive syncope is misdiagnosed as an epileptic seizure, and EEG with video during tilt table can help differentiate these conditions. However, the diagnostic utility of simultaneous EEG during tilt table testing is unknown. Prior studies have described multiple patterns of EEG changes with syncope, but others have not replicated these findings. In addition, it is unclear whether any significant EEG changes occur during severe symptomatic neurogenic orthostatic hypotension. Design/Methods: We retrospectively reviewed all consecutive tilt table studies with simultaneous EEG from April 2014 to May 2016. All patients had video EEG before (baseline) and during tilt table. All patients had at least 10 minutes of head up tilt unless they had syncope or did not tolerate the study. In addition, all patients performed deep breathing and valsalva testing. All studies were supervised and interpreted by autonomic specialists, and EEG was visually read by trained epileptologists. Results: Eighty-eight patients met the inclusion criteria. Mean age was 45 years, and 56 were women. Seven patients (~8%) had syncope during tilt table, 11 (~12%) had significant neurogenic orthostatic hypotension, another 11 (~12%) had significant orthostatic tachycardia. Nineteen(~21%) had abnormal baseline EEG. Visually discernable EEG changes were seen in only 3 patients (~3%) with syncope and in 1patient (~1%) with orthostatic tachycardia. Conclusions: In our cohort, qualitative EEG analysis based on visual inspection during tilt table study revealed abnormalities in only a few patients with syncope and in one patient with orthostatic tachycardia. No discernable EEG changes were noted in patients with severe orthostatic hypotension. Quantitative or computerized EEG analysis might be more sensitive and objective for detecting cerebral hypoperfusion during tilt table studies. Disclosure: Dr. Muppidi has received personal compensation for activities with Alexion Pharmaceuticals and Alnylam Pharmaceuticals. Dr. Razavi has received personal compensation for activities with Ceribell as a consultant. Dr. Miglis has nothing to disclose. Dr. Jaradeh has nothing to disclose.
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Objectives/Hypothesis Although the cricopharyngeus muscle is a ring‐like structure, unilateral cricopharyngeal dysfunction can produce significant dysphagia. This entity has not been well described in the literature. The aims of the study... more
Objectives/Hypothesis Although the cricopharyngeus muscle is a ring‐like structure, unilateral cricopharyngeal dysfunction can produce significant dysphagia. This entity has not been well described in the literature. The aims of the study were to identify the characteristic findings on videofluoroscopic swallow studies in patients with dysphagia secondary to unilateral cricopharyngeal dysfunction, to note the associated vagal nerve injury, and to evaluate patient outcomes following ipsilateral cricopharyngeal myotomy.Study Design Retrospective clinical investigation.Methods The clinic charts, electromyographic tests, videostroboscopic examinations, and videofluoroscopic swallow studies were reviewed from a series of patients who presented to our institution from 1993 to 2001 with dysphagia and findings on videofluoroscopic swallow studies suggestive of unilateral cricopharyngeal dysfunction on posterior–anterior view. In patients treated with ipsilateral cricopharyngeal myotomy, postoperative findings on swallow studies and patient outcomes were also reviewed.Results Eighteen patients demonstrated findings characteristic of unilateral cricopharyngeal muscle dysfunction on videofluoroscopic swallow study. The common feature was a unilateral shelf‐like barrier at the cricopharyngeus on the posterior–anterior view with pooling of liquid bolus in the ipsilateral pyriform sinus and episodic shunting to the contralateral side. Eight patients did not have evidence of cricopharyngeal dysfunction (ie, cricopharyngeal bar) on lateral films. Of the 18 patients, 14 had histories consistent with vagal injury secondary to trauma (n = 2), neoplastic involvement (n = 7), iatrogenic injury (n = 2), or central nervous system disease (n = 3). Results of videostroboscopic examinations demonstrated vocal fold motion impairment in 14 patients, and electromyographic test results confirmed unilateral vagal injuries in those who underwent electromyographic testing (n = 6). In the remaining 4 of 18 patients, videostroboscopic examinations demonstrated normal vocal fold abduction but impaired lengthening with a posterior glottic gap, and electromyographic test results (n = 4) indicated unilateral superior laryngeal nerve involvement. Of the 15 patients treated with ipsilateral cricopharyngeal myotomy, 1 patient required postoperative esophageal dilations for an esophageal stricture distal to the cricopharyngeus, whereas the remaining 14 patients had functional resolution of their dysphagia.Conclusion In patients presenting with dysphagia and evidence of unilateral vagal injury, careful assessment of posterior–anterior view on videofluoroscopic swallow study should be included to evaluate for unilateral cricopharyngeal dysfunction.
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Objective: To better characterize the profiles of patients with postural orthostatic tachycardia (POTS) seen in the Stanford Autonomic Disorders Program. Background: POTS represents an orthostatic increase in heart rate (HR) > 30 bpm... more
Objective: To better characterize the profiles of patients with postural orthostatic tachycardia (POTS) seen in the Stanford Autonomic Disorders Program. Background: POTS represents an orthostatic increase in heart rate (HR) > 30 bpm in adults, or HR > 40 bpm in children in the first 10 minutes, without sustained orthostatic hypotension (OH). The standing heart rate for all subjects is often > 120 bpm. We embarked on this project to understand various POTS phenotypes. Design/Methods: We reviewed HR and BP waveforms for 850 head-up tilt tests conducted in the past 2 years in our Lab. We reviewed the tests for 2 criteria: (1) HR increase ≥ 30 bpm above baseline for at least 3 consecutive minutes during the first 10 minutes of tilt for patients ≥ 20, and 40 bpm increase for patients Results: We eliminated 16 HR waveforms because of artifacts, and found 169 with sustained HR increase; 46 were young and 25 of these had HR increase 30 to 40 bpm. We examined the 144 remaining records for OH. We excluded one (artifact), and 9 with SBP drop exceeding 20 mmHg in the first 3 minutes of tilt. This left 134 tilt records that satisfied both criteria. These were 75% female, age 12 years to 74 years. In 60%, the HR increase started in the first 3 minutes of tilt. In 90%, the HR increase extended to 10 minutes. In 37%, the increase led to a HR ≥ 120 bpm. Conclusions: We identified 134 patients that met HR and BP criteria for exaggerated postural tachycardia. We will analyze this group to identify subtypes of POTS, and classify their HR and PB profiles. Disclosure: Dr. Jaradeh has nothing to disclose. Dr. Muppidi has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Alexion, Lundbeck. Dr. Miglis has received personal compensation for consulting, serving on a scientific advisory board, speaking, or other activities with Lundbeck, Schlesinger Associates, Defined Health, Elsevier. Dr. Sinn has nothing to disclose. Dr. Krugomova has nothing to disclose. Dr. Prieto has nothing to disclose.
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Cricopharyngeal achalasia (CA) can be defined as inadequate opening of the cricopharyngeus muscle (CPM) resulting in dysphagia. Myosin heavy chain (MHC) isoform fiber type composition and size are key determinants of muscle function.... more
Cricopharyngeal achalasia (CA) can be defined as inadequate opening of the cricopharyngeus muscle (CPM) resulting in dysphagia. Myosin heavy chain (MHC) isoform fiber type composition and size are key determinants of muscle function. These parameters have not been described in CA. It is hypothesized that there is a difference between the MHC isoform composition of the CPM in patients with the clinical diagnosis of CA and that in normal subjects. Patients who had received prior botulinum were excluded. The MHC fiber type composition and size in patients and cadaveric controls were determined by adenosine triphosphatase staining and image analysis. The CPMs of 12 CA patients (6 male, 6 female; mean age, 61 years) and 5 control cadaveric subjects (3 male, 2 female; mean age, 67 years) were analyzed. There were relatively fewer type I fibers (67%) in patients with CA than in controls (81%), but the difference was not significant (p = .18). Type I fibers were slightly smaller in CA patients (38.7 microm) than in controls (47.2 microm), but this was not significantly different (p > .05). Of the 12 CA patients, 3 had type II predominance, a feature not seen in normal subjects. Patients with CA had relatively fewer type I fibers, although the difference was not statistically significant. The MHC isoform composition and fiber size were not different between CA patients and normal subjects. This is the first report to characterize the CPM in patients with CA.
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The cauda equina region is prone to injury from a variety of causes, all of which have to be considered during the performance of spinal anesthesia. This article reviews these causes and discusses their approach.
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Purpose: Epilepsy and syncope can be difficult to distinguish, with misdiagnosis resulting in unnecessary or incorrect treatment and disability. Combined tilt-table and video EEG (vEEG) testing (tilt-vEEG) is infrequently used to parse... more
Purpose: Epilepsy and syncope can be difficult to distinguish, with misdiagnosis resulting in unnecessary or incorrect treatment and disability. Combined tilt-table and video EEG (vEEG) testing (tilt-vEEG) is infrequently used to parse these entities even at large centers. Because of the discovery of a rare case of epileptic seizure induced by head-up tilt (HUT) (no prior cases have been published), the authors sought to verify the rarity of this phenomenon. Methods: An observational, retrospective case series study of all combined tilt-vEEG studies performed at Stanford Health Care over a 2-year period was performed. Studies were grouped into categories: (1) abnormal tilt and normal vEEG; (2) abnormal vEEG and normal tilt; (3) abnormal vEEG and abnormal tilt; (4) normal tilt and normal vEEG, with neurologic symptoms; and (5) normal tilt and normal vEEG without neurologic symptoms. Results: Sixty-eight percent of patients had an abnormal study (categories A–C), with only 3% having both an abnormal tilt and an abnormal EEG (category C). Of these, one patient had a focal epileptic seizure induced by HUT. With HUT positioning, the patient stopped answering questions and vEEG showed a left temporal seizure; systolic blood pressure abruptly dropped to 89 mm Hg (64 mm Hg below baseline); heart rate did not change, but pacemaker showed increased firing (threshold: <60 bpm). Conclusions: Combined tilt-table and vEEG evaluation was able to identify a previously unreported scenario—head-up tilt provocation of an epileptic seizure—and improve treatment. Combined tilt and vEEG testing should be considered for episodes that persist despite treatment to confirm proper diagnosis.
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As previous chapters have illustrated, the oropharyngeal swallow is the end result of several coordinated neuromuscular elements: velopharyngeal closure, tongue loading, tongue pulsion, closure of the laryngeal vestibule, upper esophageal... more
As previous chapters have illustrated, the oropharyngeal swallow is the end result of several coordinated neuromuscular elements: velopharyngeal closure, tongue loading, tongue pulsion, closure of the laryngeal vestibule, upper esophageal sphincter opening, and pharyngeal clearance. It is estimated that more than 30 muscles are involved in the various stages of the swallow. Muscular disorders leading to impairment in any of these steps can cause dysphagia. A better understanding of the swallowing problems associated with these conditions may help in guiding treatment, choosing technical aids, modifying the consistency of foods, swallowing rehabilitation, and nutritional support by the non-oral route.
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ABSTRACT The spectrum of hereditary neuropathies has evolved recently as a result of the exponential growth of genetic research. For the purpose of this review, we will use Charcot-Marie-Tooth (CMT), hereditary liability to pressure palsy... more
ABSTRACT The spectrum of hereditary neuropathies has evolved recently as a result of the exponential growth of genetic research. For the purpose of this review, we will use Charcot-Marie-Tooth (CMT), hereditary liability to pressure palsy (HNPP) and hereditary sensory and autonomic neuropathies (HSAN) to illustrate the current clinical and genetic approach to such neuropathies.
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Pseudoparalysis or apparent weakness of a limb associated with septic arthritis or osteomyelitis is a well documented phenomenon. Muscular spasm associated with pain caused by the infection can lead to the apparent weakness. In contrast,... more
Pseudoparalysis or apparent weakness of a limb associated with septic arthritis or osteomyelitis is a well documented phenomenon. Muscular spasm associated with pain caused by the infection can lead to the apparent weakness. In contrast, true nerve paralysis associated with osteomyelitis is uncommon, and documentation of the electromyographic changes is rare. We describe a five-week-old male infant who had a brachial plexus neuropathy and paralysis of the right upper extremity secondary to septic arthritis of the glenohumeral joint and osteomyelitis of the proximal part of the humerus. A male infant was delivered by cesarean section after thirty-six weeks of gestation to a primiparous thirty-five-year-old woman. No problems with the use of the upper extremities were noted at birth. At the age of three weeks, the infant had projectile vomiting and was admitted to the hospital for the operative correction of pyloric stenosis. The hospital course was uneventful, and he was discharged. One week later, he was admitted to the pediatric service for evaluation of a loss of movement of the right upper extremity of several days' duration. There was no history of fever or signs of constitutional illness while the infant was at home, but the mother reported that he had had mild upper respiratory symptoms for two days. The rectal temperature on admission was 37.2 degrees Celsius, and the vital signs were stable. The physical examination revealed a palpable mass in the right axilla, and the right upper extremity was flaccid. The patient had poor grasp, active flexion of the elbow was decreased, and active abduction of the shoulder was absent. Laboratory evaluation revealed a white blood-cell count of 20,800 per cubic millimeter (20.8 x 109 per liter) with a differential of 60 per cent segmented neutrophils, 2 per cent bands, 2 per cent lymphocytes, 16 per cent …
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Research Interests: Gastroenterology, Medicine, Comorbidity, Inflammatory Bowel Disease, Humans, and 15 moreInternal Medicine, Female, Clinical, Male, Clinical Sciences, Middle Aged, Adult, Case Control Study, Crohn Disease, Confidence Interval, Inflammatory Bowel Diseases, Case Control Studies, Delivery of Health Care, Clinical Gastroenterology, and autonomic dysfunction
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The purpose of this study was to identify if a modified end-to-side repair can achieve equal results of nerve regeneration compared to an end-to-end repair using donor phrenic nerves in repair of the musculocutaneous nerve and also... more
The purpose of this study was to identify if a modified end-to-side repair can achieve equal results of nerve regeneration compared to an end-to-end repair using donor phrenic nerves in repair of the musculocutaneous nerve and also pulmonary protection. Eighteen rats were divided into three groups of six each comparing two nerve graft techniques: helicoid end-to-side plus distal oblique repair vs. traditional end-to-end repair, using a donor phrenic nerve. The saphenous nerve was used as a graft between the phrenic nerve and the musculocutaneous nerve. The third group was used as control; the musculocutaneous nerve was transected without any repair. Three months postoperatively, electrophysiology, tetanic force, moist muscle weight, histology, nerve fiber counting, and chest X-ray were evaluated. All results have shown that this modified end-to-side repair was superior to the end-to-end repair. The former did not compromise the diaphragm function, but the latter showed an elevation of the diaphragm. Little recovery was seen in the third group. The conclusion is that this modified end-to-side repair can replace the traditional end-to-end repair using donor phrenic nerves with better results of nerve regeneration without diaphragm compromise.
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To identify a suitable animal model and to delineate the neural pathway and target organs of the esophagoglottal closure reflex we studied three species. Study showed the existence of an esophagoglottal closure reflex in cats. The... more
To identify a suitable animal model and to delineate the neural pathway and target organs of the esophagoglottal closure reflex we studied three species. Study showed the existence of an esophagoglottal closure reflex in cats. The presence of this reflex could not be documented in the opossum. In monkeys, because of the inadequacy of the available recording devices, its presence could not be ascertained. In the feline model, the closure response of the vocal folds to the abrupt generalized and segmental distension of the esophagus was similar to that of the humans. Study findings indicate that among glottal adductor muscles at least interarytenoid and lateral cricoarytenoid muscles are involved as target organs of the esophagoglottal closure reflex. Decerebration did not change the frequency of glottal closure response to esophageal distension, supporting the notion that this reflex is completely under brain stem control. Bilateral cervical vagotomy abolished the glottal closure induced by esophageal distension indicating that this reflex is mediated by the vagus nerve. Upper esophageal sphincter (UES) pressure response to esophageal distension by air was variable, suggesting that glottal and UES response to esophageal distension, although closely coordinated, are not dependent on one another. In summary, an esophagoglottal closure reflex exists in feline species, and many similarities in the elicitation and mediation of this reflex have been found with that of humans. This model could be used for further physiological studies.
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The cricopharyngeal muscle (CPM) is essential for normal deglutition. Pharyngeal dysphagia commonly results from impaired or uncoordinated CPM dilation. Dysfunction of the CPM has also been implicated in the genesis of... more
The cricopharyngeal muscle (CPM) is essential for normal deglutition. Pharyngeal dysphagia commonly results from impaired or uncoordinated CPM dilation. Dysfunction of the CPM has also been implicated in the genesis of Zenker's (pharyngoesophageal) diverticulum. Despite the CPM's significance, little is understood about its morphology. We studied CPM biopsy specimens from 20 patients with Zenker's diverticulum and from 5 fresh cadaver patients with detailed histologic techniques to include fiber size and shape and adenosine triphosphatase, reduced nicotinamide adenine dinucleotide, trichrome, succinate dehydrogenase, cytochrome C oxidase, periodic acid-Schiff reaction, oil red O, acid phosphatase, Congo red, crystal violet, and monoadenylate deaminase stains. The normal CPM has unique morphological characteristics, with some myofibers having staining properties that are a hybrid between striated muscle and muscle spindle. The variable orientation of the muscle fibers is also different from that of most other striated musculature. Of the 20 Zenker CPM specimens, 4 specimens did not reveal any significant differences from controls (2 of which had insufficient amounts of tissue for complete analysis). In the remaining 16 specimens, several abnormalities existed, including excessive size variation (16/16), grouping of atrophic fibers (9/16), target or targetoid formations (4/16), cores (2/16), and ragged red fibers (2/16). The final pathological pattern of the 16 specimens was neurogenic in 7, myopathic in 4, and mixed (with neurogenic predominance) in the remaining 5. Two specimens contained significant lymphocytic inflammatory infiltrates. We conclude that the unique neuromuscular function of the CPM in deglutition is likely due to its fiber orientation and the hybrid nature of some of the myofibers. Morphological disturbances of the CPM impair its dilation and may account for the development of Zenker's diverticulum. This disturbance is most often due to progressive denervation of the CPM.
Research Interests: Pathology, Medicine, Biopsy, Anatomy, Humans, and 12 moreFemale, Male, Clinical Sciences, Aged, Middle Aged, Atrophy, Adult, Esophagus, NAD, Vagus Nerve, Nerve degeneration, and Muscle fibers skeletal
OBJECTIVESeveral recent reports suggest there may be a relationship between chronic rhinitis and extraesophageal manifestations of gastroe‐sophageal reflux (EER). It is hypothesized that this relationship is a result of autonomic nervous... more
OBJECTIVESeveral recent reports suggest there may be a relationship between chronic rhinitis and extraesophageal manifestations of gastroe‐sophageal reflux (EER). It is hypothesized that this relationship is a result of autonomic nervous system (ANS) dysfunction.STUDY DESIGNPatients with isolated vasomotor rhinitis (VR), both VR and EER, and a control group were studied by a battery of tests designed to objectively evaluate ANS function. In addition all 3 groups underwent barium esophagogram and 4‐site (proximal pharynx, distal pharynx, proximal esophagus, and distal esophagus) ambulatory pH monitoring. Adult patients fulfilling diagnostic criteria for VR, and with both VR and EER underwent objective ANS testing in a recently developed ANS testing laboratory. The control group consisted of age‐ and sex‐matched adults without diagnostic criteria for VR or EER.RESULTSIn patients with VR only (n = 9), 2 patients had a positive esophagogram, whereas a positive pharyngeal reflux probe was found in 1 and an abnormal composite autonomic scoring scale (CASS) was found in 8 (mean VR CASS = 1.750 vs control CASS 0.556, P =. 02). The group with VR and EER (n = 12) had a positive esophagogram in 10 patients, positive pharyngeal reflux by probe in 9, and all 12 had an abnormal CASS (mean CASS VR/EER = 2.909 vs CASS control = 0.556, P =. 001 and vs VR CASS = 1.750, P =. 05). The control patients (n = 9) had normal transesopohageal gastroduo‐denoscopy in 8, 1 had a positive pharyngeal probe study, and all 9 had a normal CASS. In addition ANS testing in patients with diagnostic criteria for both VR/EER revealed statistically significant evidence of an adrenergic deficit as compared with control patients on the basis of mean phase II blood pressure response to Valsalva maneuver (mean phase II VR/EER = −16.730 vs control = −7.780, P =. 05). In the VR only group, the phase II blood pressure decrease was greater than in control patients, but did not reach statistical significance (mean phase II VR = −9.370 vs control = − 7.780, P = 0.672).CONCLUSIONPatients with VR and VR/EER have objective evidence of ANS dysfunction when compared with a group of age‐ and sex‐matched control patients. Patients with both VR/EER demonstrate a significantly greater degree of ANS dysfunction than patients with isolated VR. The mechanism by which VR and EER interact is not entirely clear, but ANS dysfunction is objectively associated with both disorders. In addition, patients with VR/EER seem to demonstrate hypo‐function of the adrenergic component of the ANS, in contrast to the generally held hypothesis that VR results from increased cholinergic activity. Further characterization of the type of ANS abnormality may allow the development of novel pharmacologic therapies for these disorders.
Research Interests: Reflux, Medicine, Autonomic Nervous System, Humans, Blood Pressure, and 15 moreFemale, Male, Statistical Significance, Clinical Sciences, Middle Aged, Adult, Esophagus, Study design, Gastroesophageal Reflux, Control Group, Case Control Studies, Valsalva Maneuver, Diagnostic Criteria, Pharynx, and autonomic dysfunction
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After nerve injury, an influx of calcium exceeds the homeostatic capacity, which damages peripheral nerves. Previous studies identified that following nerve crush, function improves as calcium levels normalize. Electrophysiological... more
After nerve injury, an influx of calcium exceeds the homeostatic capacity, which damages peripheral nerves. Previous studies identified that following nerve crush, function improves as calcium levels normalize. Electrophysiological analysis was performed to measure the compound muscle action potential of 15 patients' damaged nerves. These samples were evaluated for calcium level and also stained with a Luxol fast blue and neurofilament antibodies to evaluate the myelin sheath and neurofilaments of the nerves. Based on the Sunderland scale, we identified three exclusive types of peripheral nerve injury groups. There was a correlation between histopathological damage and calcium levels of 0.81 (p < 0.005). The average relative fluorescence units (RFUs) was 235.28 ± 19, which corresponds to 5.3 × 10⁻⁷ M of calcium, five times the normal value. Our study shows promising clinical implications via faster pathology results by the RFU technique. This approach of calcium staining, though still in clinical trials, offers significant clinical application, allowing physicians to get the clinically diagnostic nerve injury degree faster and will also facilitate better strategies for further treatment or future surgeries.
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Electromyography of the cricopharyngeus muscle is helpful in the study of normal swallowing and in the evaluation of various conditions leading to dysphagia. This article describes the technical aspects of the studies and the findings in... more
Electromyography of the cricopharyngeus muscle is helpful in the study of normal swallowing and in the evaluation of various conditions leading to dysphagia. This article describes the technical aspects of the studies and the findings in normal controls and in various disease states.
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This study evaluated 2 end-to-side nerve repair techniques for ability to induce nerve sprouting and muscular recovery. Twenty-four rats underwent identical surgeries. The helicoid method of neurorrhaphy was used on the left (large... more
This study evaluated 2 end-to-side nerve repair techniques for ability to induce nerve sprouting and muscular recovery. Twenty-four rats underwent identical surgeries. The helicoid method of neurorrhaphy was used on the left (large epineurial window) side and the standard end-to-side (small epineurial window) repair on the right side of each rat to repair the peroneal nerve. The helicoid configuration markedly increases the area from which axons can sprout into the recipient nerve. At 11 months after surgery, axons were counted in donor and recipient nerves, and muscle moist weight of the extensor digitorum longus (EDL) and tetanic force were measured. Muscle volume, tetanic force, and moist weight of EDL muscles were significantly higher on the left side (helicoid) than on the right (end-to-side). Histologic analysis and nerve axon counting of the recipient peroneal nerve showed significantly more regenerative nerves on the left than on the right. There were no significant differences between sites above and below the repair site in the donor tibial nerve in regard to mean number of nerve fibers. Helicoid nerve repair can entice more nerve fiber sprouts from the intact donor nerve, improve muscular recovery, and maintain donor nerve health.
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IntroductionGastrointestinal dysfunction, particularly constipation, is among the most common non‐motor manifestations in Parkinson's Disease (PD). We aimed to identify high‐resolution anorectal manometry (HR‐ARM) abnormalities in... more
IntroductionGastrointestinal dysfunction, particularly constipation, is among the most common non‐motor manifestations in Parkinson's Disease (PD). We aimed to identify high‐resolution anorectal manometry (HR‐ARM) abnormalities in patients with PD using the London Classification.MethodsWe conducted a retrospective review of all PD patients at our institution who underwent HR‐ARM and balloon expulsion test (BET) for evaluation of constipation between 2015 and 2021. Using age and sex‐specific normal values, HR‐ARM recordings were re‐analyzed and abnormalities were reported using the London Classification. A combination of Wilcoxon rank sum and Fisher's exact test were used.Results36 patients (19 women) with median age 71 (interquartile range [IQR]: 69–74) years, were included. Using the London Classification, 7 (19%) patients had anal hypotension, 17 (47%) had anal hypocontractility, and 3 women had combined hypotension and hypocontractility. Anal hypocontractility was significantly more common in women compared to men. Abnormal BET and dyssynergia were noted in 22 (61%) patients, while abnormal BET and poor propulsion were only seen in 2 (5%). Men had significantly more paradoxical anal contraction and higher residual anal pressures during simulated defecation, resulting in more negative recto‐anal pressure gradients. Rectal hyposensitivity was seen in nearly one third of PD patients and comparable among men and women.ConclusionOur data affirms the high prevalence of anorectal disorders in PD. Using the London Classification, abnormal expulsion and dyssynergia and anal hypocontractility were the most common findings in PD. Whether the high prevalence of anal hypocontractility in females is directly related to PD or other confounding factors will require further research.
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Dysfunction of the autonomic nervous system presents a diagnostic and therapeutic challenge for many clinicians, but recent clinical advances offer new strategies to identify and manage these conditions. In the latest episode of the ANA... more
Dysfunction of the autonomic nervous system presents a diagnostic and therapeutic challenge for many clinicians, but recent clinical advances offer new strategies to identify and manage these conditions. In the latest episode of the ANA Investigates podcast, Dr Safwan Jaradeh, Professor of Neurology, Psychiatry, and Behavioral Sciences and Director of the Autonomic Disorders Program at the Stanford Neuroscience Health Center, discusses the latest clinical approach to autonomic disorders. Typical clinical syndromes of autonomic dysfunction include orthostatic intolerance, functional gastrointestinal disorders, alterations in body temperature and sweating, and genitourinary symptoms; these syndromes commonly co-occur with peripheral neuropathy or parkinsonism. A careful review of systems is critical to encapsulating the scope of autonomic dysfunction. The medical examination should include assessment of orthostatic vital signs and signs of vasomotor autonomic dysfunction, whereas the neurologic examination emphasizes pupillary assessment, reflexes, sensory examination, and a detailed parkinsonism evaluation. In the podcast, Dr Jaradeh elaborates on the details of these assessments and discusses the standard diagnostic testing of dysautonomia, including measurement of heart rate variability with deep breathing, the Valsalva ratio, and tilt table testing, the latter of which may be combined with electroencephalogram or provocative techniques including mental stress or hand grip maneuver. Advanced autonomic investigations include quantitative sudomotor axon reflex testing, thermoregulatory sweat testing, fat pad biopsy for amyloid deposition, and skin punch biopsy for epidermal and sweat gland nerve fiber density. In the podcast, Dr Jaradeh also touches on the diagnosis and treatment of postural orthostatic tachycardia syndrome, which entails a mismatch between the hemodynamic demands of the body during postural changes that leads to an exaggerated heart rate increase with position change. He also discusses the treatment of refractory orthostatic intolerance, including countermaneuvers such as elastic stockings and abdominal binders, and pharmacologic therapy. Dr Jaradeh concludes the podcast with a discussion of the most significant unanswered questions in the evaluation of autonomic disorders. He describes opportunities for future research in the field, including expanding upon known genomic associations, improvement of symptomatic therapies, and treatment to halt or reverse the progression of the host of neurogenerative disorders associated with autonomic dysfunction. Suggested Supplemental Material:
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With the goal of better defining the types of bladder dysfunction observed in this population, we present the chief urologic complaints, results of urodynamic studies, and treatments of patients with dysautonomia-related urinary symptoms.... more
With the goal of better defining the types of bladder dysfunction observed in this population, we present the chief urologic complaints, results of urodynamic studies, and treatments of patients with dysautonomia-related urinary symptoms. All patients with dysautonomia referred to our neurourology clinic between 2005 and 2015 for management of lower urinary tract dysfunction were retrospectively reviewed. Each patient's chief urologic complaint was recorded and used to initially characterize the bladder storage or voiding symptoms. Patient evaluation included history and physical examination, urinalysis, post void bladder ultrasound, and urodynamic studies. Successful treatment modalities that subjectively or objectively improved symptoms were recorded. Of 815 patients with the diagnosis of dysautonomia, 82 (10 %) were referred for evaluation of lower urinary tract dysfunction. Mean age was 47 years (range 12-83) and 84 % were female. The chief complaint was urinary urgency ± incontinence in 61 % and hesitancy in 23 % of patients. Urodynamic findings demonstrated detrusor overactivity ± incontinence in 50 % of patients, although chief complaint did not reliably predict objective findings. Successful objective and subjective treatments were multimodal and typically non-operative. Lower urinary tract dysfunction may develop in at least 10 % of patients with dysautonomia, predominantly females. Bladder storage or voiding complaints do not reliably predict urodynamic findings. Urodynamically, most patients exhibited detrusor overactivity. The majority of patients were successfully managed with medical or physical therapy.
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Spin-lock imaging is a new magnetic resonance imaging (MRI) technique used to reflect the microstructural integrity of muscle. The purpose of this study was to characterize spin-lock contrast (SLC) of calf muscles in limb girdle muscular... more
Spin-lock imaging is a new magnetic resonance imaging (MRI) technique used to reflect the microstructural integrity of muscle. The purpose of this study was to characterize spin-lock contrast (SLC) of calf muscles in limb girdle muscular dystrophy (LGMD). The calf muscles of 5 patients with LGMD and 10 healthy volunteers were imaged with an off-resonance magnetic resonance (MR) spin-lock suppression pulse. Spin-lock suppression ratios were calculated for anterior tibialis, posterior tibialis, soleus, and gastrocnemius muscles. Clinical assessments of muscle strength were compared to the spin-lock suppression ratios in the LGMD group. Strong SLC was observed in healthy muscles, with mean (+/- SD) suppression ratios ranging from 51.2% (+/- 3.6%) to 56.3% (+/- 1.3%). In diseased muscle, spin-lock signal suppression was reduced by 8%-70%, demonstrating an inverse correlation between symptom duration and suppression ratios. Spin-lock contrast in the patients with LGMD, as a reflection of tissue integrity, was best preserved in posterior tibialis, anterior tibialis, soleus, and gastrocnemius muscles in descending order. Clinical assessments did a poorer job of differentiating than SLC did and were in poor agreement with spin-lock suppression ratios. Spin-lock MRI can quantify microstructural changes in LGMD and appears to provide information not obtainable from clinical evaluations. This suggests that this noninvasive technique may be useful in evaluating the extent, progression, and response to therapy of LGMD.
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Seven patients with a sensorimotor peripheral neuropathy followed years later by extrapyramidal manifestations are presented. This appears to be a separate genetic disorder(s) from that described as Machado-Joseph disease. In five... more
Seven patients with a sensorimotor peripheral neuropathy followed years later by extrapyramidal manifestations are presented. This appears to be a separate genetic disorder(s) from that described as Machado-Joseph disease. In five subjects, other relatives had similar multisystem involvement. None was of known Portuguese ancestry. The extrapyramidal syndrome was mainly parkinsonian. Pain was prominent in five subjects. In all cases, low or moderate doses of levodopa/carbidopa ameliorated both the pain and the parkinsonian features. In one patient, a randomized placebo-controlled trial of levodopa/carbidopa was found to significantly improve most symptoms and neurologic dysfunction scores related to the extrapyramidal syndrome.
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ObjectiveAlthough cricopharyngeal electromyography (CP‐EMG) is recognized as a diagnostic tool for dysphagia assessment, few reports in the literature characterize CP‐EMG abnormalities in relation to clinical presentation. The aim of this... more
ObjectiveAlthough cricopharyngeal electromyography (CP‐EMG) is recognized as a diagnostic tool for dysphagia assessment, few reports in the literature characterize CP‐EMG abnormalities in relation to clinical presentation. The aim of this study was to review a large series of CP‐EMG studies, and compare the CP‐EMG results with the patients' diagnoses.MethodsA retrospective review of all CP‐EMG performed at our institution over a 10‐year period was executed. CP‐EMG findings were then compared with the patients' clinical history, focusing on potential etiologies of neurogenic injury.ResultsSeventy CP‐EMGs were reviewed, with 47 (67%) demonstrating neural injury. Of those cases with neural injury on EMG, 29 (60%) had known vagal injuries, 13 (28%) had idiopathic nerve palsies, and 5 (11%) had central etiologies, such as stroke. Each of these three neurogenic subgroups revealed a distinct pattern of EMG abnormalities.ConclusionThis study suggests there is an association between patterns of CP‐EMG abnormalities and underlying etiology based on clinical history.