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Dive into the research topics where Jennifer Noeller is active.

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Featured researches published by Jennifer Noeller.


Clinical Neurology and Neurosurgery | 2014

Post-traumatic syringomyelia: outcome predictors.

Youssef R. Karam; Patrick W. Hitchon; Nakhle E. Mhanna; Wenzhuan He; Jennifer Noeller

OBJECTIVE To identify risk factors that predispose to post-traumatic syringomyelia (PTS) and describe the outcome of surgical management. METHODS Retrospective cohort study of 27 patients with post-traumatic syringomyelia. Spinal cord injury of these patients spanned the period from 1963 to 2008. All data were collected retrospectively using available medical records and radiological images. RESULTS There were 24 males and 3 females. The level of initial spine injury was thoracic in 21, cervical in 4, and lumbar in 2. The average age (±SD) at diagnosis of PTS was 40±13 years. The mean follow-up ±SD from injury was 18±11 years. On admission after injury, there were 14 patients with American Spinal Injuries Association (ASIA) disability scores of A, 3 with ASIA C, and 10 with ASIA score of D. At the time of diagnosis of PTS, local kyphosis at the site of injury measured 28±12°, and the residual canal was 67±19% compared to the average rostral and caudal anteroposterior diameter. Fourteen patients underwent a single operation for PTS, and 13 needed two or more procedures. In the 11 patients in whom the initial surgery included a duraplasty, 3 required reoperation for unsuccessful reduction in the size of the syrinx and failure to improve symptoms. In the 16 patients in whom the initial procedure was that of a shunt alone, 10 required revision (p=0.0718 rate of revision between shunting and duraplasty). As a result of treatment for PTS, improvement in symptoms of PTS occurred in 14, symptoms were unchanged in 10, and progressed in 3. In the 11 patients with sequential MRI scans, a significant correlation was shown between the reduction in the size of the syrinx and clinical improvement (p<0.001). CONCLUSION PTS is often the result of severe spinal cord injuries, with over half of patients having an ASIA disability score of A. Our review corroborates other published reports showing that PTS is associated with significant deformity and stenosis. Irrespective of treatment, over half of the patients required reoperation for their PTS. Duraplasty and arachnolysis are the preferred treatment for PTS over shunting alone. Treatment was associated with cessation of symptoms or improvement in nearly 90% of the patients.


Journal of Neurosurgery | 2015

Minimally invasive resection of lumbar intraspinal synovial cysts via a contralateral approach: review of 13 cases.

Hamdi G. Sukkarieh; Patrick W. Hitchon; Olatilewa Awe; Jennifer Noeller

OBJECT The authors sought to determine patient-related outcomes after minimally invasive surgical (MIS) lumbar intraspinal synovial cyst excision via a tubular working channel and a contralateral facet-sparing approach. METHODS All the patients with a symptomatic lumbar intraspinal synovial cyst who underwent surgery at the University of Iowa Hospitals and Clinics with an MIS excision via a contralateral approach were treated between July 2010 and August 2014. There was a total of 13 cases. Each patient was evaluated with preoperative neurological examinations, lumbar spine radiography, MRI, and visual analog scale (VAS) scores. The patients were evaluated postoperatively with neurological examinations and VAS and Macnab scores. The primary outcomes were improvement in VAS and Macnab scores. Secondary outcomes were average blood loss, hospital stay duration, and operative times. RESULTS There were 5 males and 8 females. The mean age was 66 years, and the mean body mass index was 28.5 kg/m(2). Sixty-nine percent (9 of 13) of the cysts were at L4-5. Most patients had low-back pain and radicular pain, and one-third of them had Grade 1 spondylolisthesis. The mean (± SD) follow-up duration was 20.8 ± 16.9 months. The mean Macnab score was 3.4 ± 1.0, and the VAS score decreased from 7.8 preoperatively to 2.9 postoperatively. The mean operative time was 123 ± 30 minutes, with a mean estimated blood loss of 44 ± 29 ml. Hospital stay averaged 1.5 ± 0.7 days. There were no complications noted in this series. CONCLUSIONS The MIS excision of lumbar intraspinal synovial cysts via a contralateral approach offers excellent exposure to the cyst and spares the facet joint at the involved level, thus minimizing risk of instability, blood loss, operative time, and hospital stay. Prospective randomized trials with longer follow-up times and larger cohorts are needed to conclusively determine the superiority of the contralateral MIS approach over others, including open or ipsilateral minimally invasive surgery.


Clinical Neurology and Neurosurgery | 2015

The Cost-Effectiveness of Surgery for Trigeminal Neuralgia in Surgically Naïve Patients: a Retrospective study.

Marshall T. Holland; Jennifer Noeller; John M. Buatti; Wenzhuan He; E. Torage Shivapour; Patrick W. Hitchon

OBJECTIVE For 75% of patients with trigeminal neuralgia (TN), the pain can be controlled with medication. For those who fail medication therapy, surgical options include microvascular decompression (MVD), percutaneous radiofrequency rhizotomy (RFR), and stereotactic radiosurgery (SRS). Few studies have explored the relative cost-effectiveness of these interventions, particularly in surgically naïve patients. METHODS A retrospective chart review performed between January 2003 and January 2013 identified a total of 89 patients who underwent surgical treatment for TN (MVD=27, RFR=23, SRS=39). Outcome measures included facial pain (excellent=no pain, no medications; good=no pain, medications required; fair=>50% decrease in pain; and poor=<50% decrease in pain/secondary surgery), numbness, cost, and the need for a subsequent procedure. RESULTS The average age of patients for each procedure was MVD=53.9±16, RFR=76.2±16, and SRS=74.5±12 (p<0.001 MVD vs. other modalities). Total charges for the procedures (US dollars) were MVD=50,100±9600, RFR=4700±2200, and SRS=39,300±6000 (p<0.001). Actual collections varied by insurance. Percentages of postoperative facial numbness were MVD=11%, RFR=52%, and SRS=28% (p<0.01). At two years, the rates of recurrence requiring a second procedure were MVD=22%, RFR=74%, and SRS=31% (p<0.01). Average times to secondary procedure in months were MVD=26±29, RFR=59±76, and SRS=35±25. Mean quality adjusted pain-free years were MVD=1.58, RFR=2.28, and SRS=0.99. Cost-effectiveness calculations in US dollars showed MVD=31,800, RFR=2100, and SRS=39,600 (p<0.001). CONCLUSION There are significant cost differences among the three most common surgical procedures for TN. MVD was the most expensive procedure, was more likely to be performed on younger patients, had the lowest rate of facial numbness, and had the lowest rate of recurrence requiring a secondary procedure. SRS was slightly less costly, more likely to be performed on an older population, and had a rate of recurrence similar to MVD. RFR was the least expensive procedure, provided immediate relief, but was associated with the highest rates of facial numbness and recurrence. Based on cost-effectiveness, considering both cost and outcome, RFR was the most cost-effective, followed by MVD, and finally SRS.


Clinical Neurology and Neurosurgery | 2013

Alternative grafts in anterior cervical fusion.

Fangxiang Chen; Wenzhuan He; Kelly B. Mahaney; Jennifer Noeller; Nakhle E. Mhanna; Stephen Viljoen; James C. Torner; Patrick W. Hitchon

OBJECTIVE The present retrospective study was conducted to compare the clinical and radiographic outcomes in patients undergoing anterior cervical discectomy with fusion (ACDF) using carbon fiber reinforced polymer (CFRP) cages, or allograft. METHODS We retrospectively reviewed cases of ACDF using allograft in 20 patients, and CFRP in 19 who had sequential radiographs before and after surgery, and at 1 year. RESULTS There were no apparent significant differences between the 2 groups in age (p=0.057), gender (p=0.635), or complications (p=0.648). At 12 months, there were no cases of construct failure, and fusion appeared to have been achieved in patients of both groups. Lordosis was increased significantly in both groups after surgery (p<0.001 in allograft and p=0.025 in CFRP), and was maintained up until 1 year (p<0.018 in allograft and p=0.05 in CFRP) without a difference between groups (p=0.721). Anterior interbody height was significantly increased (p<0.001 in both groups at each time points) after surgery, without a significant difference between groups (p>0.21). This increase in height was greatest in magnitude immediately after surgery, and declined with the passage of time. There was no detectable health-related quality of life difference between allograft and CFRP group after surgery (p>0.05). CONCLUSION The present study demonstrates that CFRP cages appear to have comparable fusion rates, restoration of lordosis and disc space height, and complication rates to patients who undergo ACDF with allograft.


Clinical Neurology and Neurosurgery | 2015

Microvascular decompression and MRI findings in trigeminal neuralgia and hemifacial spasm. A single center experience.

Patrick W. Hitchon; Mario Zanaty; Toshio Moritani; Ergun Y. Uc; Connie Pieper; Wenzhuan He; Jennifer Noeller

OBJECTIVE For patients with medically unresponsive trigeminal neuralgia (TIC) and hemifacial spasm (HS), surgical microvascular decompression (MVD) is the procedure of choice. The authors of this report sought to review their outcomes with MVD in patients with TIC and HS, and the success of preoperative magnetic resonance imaging (MRI) in identifying the offending vascular compression. METHODS Since 2004, there were a total of 51 patients with TIC and 12 with HS with available MRI scans. All patients underwent preoperative MRI to rule out non-surgical etiologies for facial pain and facial spasm, and confirm vascular compression. Follow-up after surgery was 13 ± 22 months for the patients with TIC and 33 ± 27 months for the patients with HS. RESULTS There were 45 responders to MVD in the TIC cohort (88%), with a Visual Analog Score (VAS) of 1 ± 3. All patients with HS responded to MVD between 25 and 100%, with a mean of 75 ± 22%. Wound complications occurred in 10% of patients with MVD for TIC, and 1 patient reported hearing loss after MVD for HS, documented by audiogram. The congruence rate between the preoperative MRI and operative findings of vascular compression was 84% in TIC and 75% in HS. CONCLUSION MVD is an effective and safe modality of treatment for TIC and HS. In addition to ruling out structural lesions, MRI can offer additional information by highlighting vascular loops associated with compressions. On conventional scans as obtained here, the resolution of MRI was congruent with operative findings in 84% in TIC and 75% in HS. This review emphasizes that the decision to undertake MVD in TIC or HS should be based on clinical diagnosis and not visualization of a compressing vessel by MRI. Conversely, the presence of a compressing vessel by MRI demands perseverance by the surgeon until the nerve is decompressed.


Clinical Neurology and Neurosurgery | 2016

Options in Treating Trigeminal Neuralgia: Experience With 195 Patients.

Patrick W. Hitchon; Marshall T. Holland; Jennifer Noeller; Mark C. Smith; Toshio Moritani; Nivedita U. Jerath; Wenzhuan He

OBJECTIVE For patients with medically unresponsive trigeminal neuralgia (TN), surgical options include microvascular decompression (MVD), radiofrequency rhizotomy (RF), and stereotactic radiosurgery (SRS). In an attempt to identify the risks and benefits and cost inherent with each of the three modalities, we performed a retrospective review of our experience with 195 cases of TN treated over the past 15 years. METHODS Since 2001, 195 patients with previously untreated TN were managed: with MVD in 79, RF in 36, and SRS in 80. All patients reported herein underwent preoperative MRI. Women outnumbered men 122/73 (p=0.045). Follow-up after surgery was 32±46months. RESULTS The patients qualifying for MVD were generally healthier and younger, with a mean age±SD of 57±14, compared to those undergoing RF (75±15) or SRS (73±13, p<0.0001). In case of relapse, medical treatment was always tried and failed prior to consideration of surgical intervention. A second surgical procedure was necessary in 2, 23, and 18 patients initially treated with MVD, RF, and SRS respectively (p<0.0001). In the patients treated with MVD, RF, and SRS, the average number of procedures per patient necessary to achieve pain control was 1.1, 2.0, and 1.3 respectively (p=0.001). There were 7 complications in the patients treated with MVD but no deaths. Numbness was present in 13, 18, and 29 patients treated with MVD, RF, and SRS respectively (p=0.008). CONCLUSION MVD for TN is the treatment least likely to fail or require additional treatment. Patients who underwent MVD were younger than those undergoing RF or SRS. The highest rate of recurrence of TN was encountered in patients undergoing RF (64%). Facial numbness was least likely to occur with MVD (16%) compared to RF and SRS (50% and 36% respectively).


Spine | 2016

Nonoperative Management in Neurologically Intact Thoracolumbar Burst Fractures: Clinical and Radiographic Outcomes.

Patrick W. Hitchon; Kingsley Abode-Iyamah; Nader S. Dahdaleh; Christopher Shaffrey; Jennifer Noeller; Wenzhuan He; Toshio Moritani

Study Design. Retrospective cohort study. Objective. The identification of factors that lead to the failure of nonoperative management in neurologically intact thoracolumbar burst fractures. Summary of Background Data. The treatment of thoracolumbar burst fractures (TLBF) can be controversial, particularly in the neurologically intact. Surgery for intact burst fractures has been advocated for early mobilization and a shorter hospital stay. These goals, however, have not always been achieved, rejuvenating an interest in nonoperative treatment. Methods. Sixty-eight neurologically intact patients with burst fractures of the thoracolumbar junction (T11-L2), and a thoracolumbar injury classification and severity score (TLICS) of 2, were treated at our institution. Based on CT scans, patients were scored based on the load-sharing classification (LSC) scale. Initial treatment consisted of bracing in clamshell thoracolumbar orthosis and gradual mobilization. Results. Owing to pain limiting mobilization, 18 patients failed nonoperative management and required instrumentation. Those who failed nonsurgical management were significantly more kyphotic (8°±10) and stenotic (52% ± 14%) than those successfully treated nonoperatively (3°±7 and 63 ± 12%, respectively). The LSC score of those undergoing surgery (6.9 ± 1.1) was also greater than those successfully treated nonoperatively (5.8 ± 1.3, P = 0.006). Length of hospitalization was longer, and hospital charges higher in those requiring surgery compared to the nonoperative group. At follow-up there was no difference between groups in the visual analog score for pain (VAS) or the Oswestry disability index. Conclusion. Owing to pain limiting mobilization, a quarter of neurologically intact patients with thoracolumbar burst fractures and a TLICS score of 2 failed nonsurgical management. The greater the kyphosis, stenosis, and fragmentation of the fracture, the more likely patients required surgery. In addition to the TLICS classification, other radiographic and clinical parameters should be included in selecting appropriate treatment strategy. The cost savings with nonoperative treatment of intact burst fractures, when appropriate, are significant. Level of Evidence: 3


British Journal of Neurosurgery | 2014

Predictors of outcome in the non-operative management of thoracolumbar and lumbar burst fractures

Patrick W. Hitchon; Wenzhuan He; Stephen Viljoen; Nader S. Dahdaleh; Rajinder Kumar; Jennifer Noeller; James C. Torner

Abstract Aim. Burst fractures without neurological deficit are often treated successfully without surgery. A subgroup may fail non-operative treatment owing to pain, and opt for surgery.The following review was conducted to identify predictors of success or failure in the non-operative treatment of thoracolumbar burst fractures. Methods. A cohort of 60 patients with T11-L4 thoracolumbar burst fractures were treated non-operatively, with bed rest and bracing until the pain abated sufficiently to allow mobilization. Patients were followed prospectively for a mean ± SD of 12 ± 14 months, and their data were reviewed retrospectively. Results. Fifty-one patients successfully completed non-operative treatment. Owing to intractable pain in nine, surgery was undertaken. Ages in the non-operative and operative groups were 46 ± 18 and 68 ± 15 years respectively (p = 0.002). The residual canal and angulation at the site of the fracture were 63 ± 12% and 1.6 ± 8.4° in the non-operative group and 47 ± 15% and 6.6 ± 13.6° in the surgical group (p = 0.001 and 0.149 between groups, respectively). Regression analysis of age, gender, angulation, and residual canal showed that only age (OR, 1.099; 95% CI, 1.022–1.183; p = 0.011) and residual canal (OR, 0.795; 95% CI, 0.642–0.985; p = 0.035) were significant predictors of failure, ultimately undergoing surgery. Conclusion. Non-surgical treatment was more likely to prove sufficient in patients aged 46 ± 18 years, and residual canal of 63 ± 12%, than in older patients with ages of 68 ± 15, and canal of 47 ± 15%. The latter group was more likely to fail, undergoing surgery because of pain or instability.


Clinical Neurology and Neurosurgery | 2016

Risk factors and outcomes in thoracic stenosis with myelopathy: A single center experience

Patrick W. Hitchon; Kingsley Abode-Iyamah; Nader S. Dahdaleh; Andrew J. Grossbach; Najib E. El Tecle; Jennifer Noeller; Wenzhuan He

OBJECTIVE Identify risk factors predisposing to thoracic spinal stenosis and myelopathy (TS) and address treatment options and outcomes. METHODS A retrospective review of our centers experience with TS over 10 years. Clinical and magnetic resonance imaging (MRI) data, surgical intervention and outcomes using Frankel and Japanese Orthopedic Association (JOA) scales were collected. RESULTS A total of 44 patients with TS were identified. There were 30 men and 14 women with a mean age±SD of 66±15years. Neurological performance was evaluated using the Frankel scale (A-E or 1-5), and JOA scale for myelopathy (0-11). Frankel scores (1-5) and JOA scores (0-11) on admission were 3.5±0.9 and 6.8±2.6 respectively. At follow-up, Frankel scores had improved to 4.1±0.8 (p=0.041) and JOA scores had improved to 8.3±2.4 (p=0.021). The presence on admission of increased signal from the cord on T2-weighted MRI was associated with lower Frankel and JOA scores (3.3±0.9, and 6.2±2.5 respectively) than in those with absent increased signal (4.0±0.4 and 8.6±2.1, p=0.02 and p=0.008 respectively). There were 4 complications, requiring exploration and debridement for dehiscence in 3 and an epidural hematoma in the fourth that necessitated evacuation, with a good outcome. A fifth patient underwent reoperation at the same level 18 months later for persistent stenosis. CONCLUSION Thoracic stenosis with myelopathy should be entertained in patients with myelopathy. Over half of our patients with TS were over the age of 70, and men outnumbered women by a ratio of 2:1. Nearly half the patients with TS had concomitant cervical and/or lumbar degenerative disease warranting surgery also. Increased signal intensity on T2-weighted MRI images correlated with lower Frankel and JOA scores compared to those without. Decompression for thoracic stenosis is associated with neurological improvement.


Clinical Neurology and Neurosurgery | 2018

C5 palsy following posterior decompression and instrumentation in cervical stenosis: Single center experience and review

Patrick W. Hitchon; Toshio Moritani; Royce W. Woodroffe; Kingsley Abode-Iyamah; Najib E. El Tecle; Jennifer Noeller; Reem K. Elwy; Kirill V. Nourski

OBJECTIVE Causation and avoidance of C5 palsy after laminectomy have proven elusive, with multiple factors incriminated including width of the laminectomy, spinal cord migration, C5 neural foraminal stenosis, or intraoperative C5 root traction. In an attempt to identify risk factors for C5 palsy after decompression in cervical stenosis and myelopathy, the following review was conducted. This report is from a single center with consistent criteria for diagnosis and management of cervical stenosis and myelopathy. PATIENTS AND METHODS We retrospectively reviewed 63 patients with cervical stenosis and myelopathy who had been treated with laminectomy with instrumentation at the C4-6 level. Imaging studies reviewed included plain X-ray films, magnetic resonance imaging (MRI), and computed tomography (CT) scans of the cervical spine. Health-related outcomes were assessed before and at follow-up and included Visual Analog Scale (VAS) for pain (1-10), Japanese Orthopedic Association (JOA) score for myelopathy (0-18), and SF-36 physical functioning, energy and fatigue, and general health categories (0-100). RESULTS In 53 patients (control group), decompression and instrumentation was accomplished without incident, but 5 patients developed lasting postoperative C5 palsy. At follow-up, there were overall significant improvements in VAS, JOA, and SF-36 physical functioning and general health domains. Subsequent to surgery, a loss of lordosis of 5° and an increase in C2 sagittal vertical axis (SVA) of 17 mm was significant. There was, however, no significant difference between control and C5 palsy patients in lordosis and C2 SVA, before or after surgery. Postoperative MRI studies were obtained in 15 of the control patients and 6 of the C5 palsy patients. Postoperative width of the laminectomy as well as the caliber of the C5 neural foramina in the control and C5 palsy cohorts were not statistically different. Though the posterior displacement of the cord in the C5 palsy cohort was larger than in controls, this difference was also not significant. CONCLUSION The above findings suggest that the cause of C5 palsy remains elusive. Though our incidence of lasting C5 palsy subsequent to laminectomy and instrumentation was 8%, it is probably under-reported. In our experience, laminectomy and instrumentation failed to increase lordosis and, in fact, were associated with an increase in positive cervical balance. Complications with cervical laminectomy and instrumentation are not by any means rare, and need to be emphasized in counselling patients, and selecting the approach.

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Patrick W. Hitchon

Roy J. and Lucille A. Carver College of Medicine

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Toshio Moritani

University of Iowa Hospitals and Clinics

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Kingsley Abode-Iyamah

University of Iowa Hospitals and Clinics

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Marshall T. Holland

University of Iowa Hospitals and Clinics

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