Hemispheric disconnection in the form of hemispherectomy or hemispherotomy is the most effective way of treating intractable hemispheric epilepsy. Anatomical hemispherectomy approaches have largely been abandoned in most cases due to a higher risk of superficial hemosiderosis, intraoperative blood loss, hydrocephalus, prolonged hospital stay, and mortality compared to the variety of tissue-sparing hemispherotomy techniques. Disconnective hemispherotomy approaches utilize the lateral ventricle as a key component of the surgical corridor. Without a lateral ventricle, disconnective surgery becomes significantly challenging, typically leading to a hemispherectomy. The authors present the case of a patient with severe hemispheric dysplasia without a lateral ventricle on the pathologic side and detail a novel surgical technique for a prone, occipital interhemispheric, tissue-sparing, purely disconnective aventricular hemispherotomy with an excellent surgical outcome.
Cameron Brimley, Vivek P. Buch, Jared M. Pisapia and Benjamin C. Kennedy
Peter J. Madsen, Shih-Shan Lang, Jared M. Pisapia, Phillip B. Storm, Robert W. Hurst and Gregory G. Heuer
Pial arteriovenous fistulas (PAVFs) are a rare form of cerebrovascular disease that tend to be overrepresented in the pediatric population. There have been limited studies of the clinical features and outcomes in this group of patients. Here, the authors attempt to better delineate this clinical entity with institutional cases and a review of the literature.
A retrospective review of cases at our institution was performed to identify all pediatric patients treated for a PAVF between 2000 and 2012.
Five patients treated for a PAVF were identified. Patients had a mean age of 1.9 years at diagnosis, and the most common presenting symptoms were seizure and macrocephaly. Patients were treated primarily with embolization, and 3 patients required both N-butyl cyanoacrylate (NBCA) glue and coiling. Four of the patients had complete obliteration of the PAVF and had a pediatric overall performance category score of either 1 (n = 3) or 2 (n = 1) at follow-up. There was 1 death due to heart failure. Analysis of the literature review suggested that a younger age or presence of intracerebral hemorrhage (ICH) or congestive heart failure (CHF) at presentation likely predicts a worse prognosis. Older patients presented more often with ICH, whereas younger patients presented significantly more often in CHF. The majority of pediatric patients reported on in the literature were treated with endovascular embolization, most commonly with NBCA glue alone. Most patients (65.4%) in the literature had an excellent outcome without neurological deficit.
Pial AVFs represent a serious yet rare form of cerebrovascular disease. Pediatric patients with ICH or CHF at presentation or those who are very young are likely to have a worse prognosis. Endovascular management of these patients has greatly changed the natural history of this disease, but the complication and mortality rates suggest the need for continued insights and advances in treatment.
Jared M. Pisapia, Casey H. Halpern, Noel N. Williams, Thomas A. Wadden, Gordon H. Baltuch and Sherman C. Stein
Roux-en-Y gastric bypass is the gold standard treatment for morbid obesity, although failure rates may be high, particularly in patients with a BMI > 50 kg/m2. With improved understanding of the neuropsychiatric basis of obesity, deep brain stimulation (DBS) offers a less invasive and reversible alternative to available surgical treatments. In this decision analysis, the authors determined the success rate at which DBS would be equivalent to the two most common bariatric surgeries.
Medline searches were performed for studies of laparoscopic adjustable gastric banding (LAGB), laparoscopic Roux-en-Y gastric bypass (LRYGB), and DBS for movement disorders. Bariatric surgery was considered successful if postoperative excess weight loss exceeded 45% at 1-year follow-up. Using complication and success rates from the literature, the authors constructed a decision analysis model for treatment by LAGB, LRYGB, DBS, or no surgical treatment. A sensitivity analysis in which major parameters were systematically varied within their 95% CIs was used.
Fifteen studies involving 3489 and 3306 cases of LAGB and LRYGB, respectively, and 45 studies involving 2937 cases treated with DBS were included. The operative successes were 0.30 (95% CI 0.247–0.358) for LAGB and 0.968 (95% CI 0.967–0.969) for LRYGB. Sensitivity analysis revealed utility of surgical complications in LRYGB, probability of surgical complications in DBS, and success rate of DBS as having the greatest influence on outcomes. At no values did LAGB result in superior outcomes compared with other treatments.
Deep brain stimulation must achieve a success rate of 83% to be equivalent to bariatric surgery. This high-threshold success rate is probably due to the reported success rate of LRYGB, despite its higher complication rate (33.4%) compared with DBS (19.4%). The results support further research into the role of DBS for the treatment of obesity.
Jennifer Hong, Jared M. Pisapia, Zarina S. Ali, Austin J. Heuer, Erin Alexander, Gregory G. Heuer and Eric L. Zager
Neurogenic thoracic outlet syndrome (nTOS) is an uncommon compression syndrome of the brachial plexus that presents with pain, sensory changes, and motor weakness in the affected limb. The authors reviewed the clinical presentations and outcomes in their series of pediatric patients with surgically treated nTOS over a 6-year period.
Cases of nTOS in patients age 18 years or younger were extracted for analysis from a prospective database of peripheral nerve operations. Baseline patient characteristics, imaging and neurophysiological data, operative findings, and outcomes and complications were assessed.
Twelve patients with 14 cases of nTOS surgically treated between April 2010 and December 2016 were identified. One-third of the patients were male, and 2 male patients underwent staged, bilateral procedures. Disabling pain (both local and radiating) was the most common presenting symptom (100%), followed by numbness (35.7%), then tingling (28.6%). The mean duration of symptoms prior to surgery was 15.8 ± 6.6 months (mean ± SD). Sports-related onset of symptoms was seen in 78.6% of cases. Imaging revealed cervical ribs in 4 cases, prominent C-7 transverse processes in 4 cases, abnormal first thoracic ribs in 2 cases, and absence of bony anomalies in 4 cases. Neurophysiological testing results were normal in 85.7% of cases. Conservative management failed in all patients, with 5 patients reporting minimal improvement in symptoms with physical therapy. With a mean follow-up after surgery of 22 ± 18.3 months (mean ± SD), pain relief was excellent (> 90%) in 8 cases (57.1%), and good (improved > 50%) in 6 cases (42.9%). On univariate analysis, patients who reported excellent pain resolution following surgery at long-term follow-up were found to be significantly younger, and to have suffered a shorter duration of preoperative symptoms than patients who had worse outcomes. Lack of significant trauma or previous surgery to the affected arm was also associated with excellent outcomes. There were 4 minor complications in 3 patients within 30 days of surgery: 1 patient developed a small pneumothorax that resolved spontaneously; 1 patient suffered a transient increase in pain requiring consultation, followed by hiccups for a period of 3 hours that resolved spontaneously; and 1 patient fell at home, with transient increased pain in the surgically treated extremity. There were no new neurological deficits, wound infections, deep vein thromboses, or readmissions.
Pediatric nTOS commonly presents with disabling pain and is more frequently associated with bony anomalies compared with adult nTOS. In carefully selected patients, surgical decompression of the brachial plexus results in excellent pain relief, which is more likely to be seen in younger patients who present for early surgical evaluation.
Bert W. O'Malley Jr., M. Sean Grady, Brandon C. Gabel, Marc A. Cohen, Gregory G. Heuer, Jared Pisapia, Leif-Erik Bohman and Jason M. Leibowitz
The endoscopic endonasal approach for resection of pituitary lesions is an effective surgical option for tumors of the sella turcica. In this study the authors compared outcomes after either purely endoscopic resection or traditional microscope-aided resection. They also attempted to determine the learning curve associated with a surgical team converting to endoscopic techniques.
Retrospective data were collected on patients who were surgically treated for a pituitary lesion at the Hospital of the University of Pennsylvania between July 2003 and May 2008. Age, sex, race, presenting symptoms, length of hospital stay, surgical approach, duration of surgery, tumor pathological features, gross-total resection (GTR) of tumor, recurrence of the lesion, and intraoperative and postoperative complications were noted. All procedures were performed by the same senior neurosurgeon, who was initially unfamiliar with the endoscopic endonasal approach.
A total of 25 patients underwent microscopic resection and 25 patients underwent endoscopic resection performed by a single skull base team consisting of the same senior neurosurgeon and otorhinolaryngologist (M.S.G. and B.W.O.). In the microscopically treated cohort, there were 8 intra- or postoperative complications, 6 intraoperative CSF leaks, 17 (77%) of 22 patients had GTR on postoperative imaging, 5 patients underwent ≥ 2 operations, and 10 (59%) of 17 patients reported total symptom resolution at follow-up. The endoscopically treated group had 7 intraor postoperative complications and 7 intraoperative CSF leaks. Of the patients who had pre- and postoperative imaging studies, 14 (66%) of 21 endoscopically treated patients had GTR; 4 patients had ≥ 2 operations, and 10 (66%) of 15 patients reported complete symptom resolution at follow-up. The first 9 patients who were treated endoscopically had a mean surgical time of 3.42 hours and a mean hospital stay of 4.67 days. The next 8 patients treated had a mean surgical time of 3.11 hours and a mean hospital stay of 3.13 days. The final 8 patients treated endoscopically had a mean surgical time of 2.22 hours and a mean hospital stay of 3.88 days. The difference in length of operation between the first 9 and the last 8 patients treated endoscopically was significantly different. There was a trend toward decreased CSF leaks and other complications from the first 2 groups compared with the third group.
In this subset of patients, the use of endoscopic endonasal resection results in a similar complication and symptom resolution rate compared with traditional techniques. The authors postulate that the learning curve for endoscopic resection can be ≤ 17 procedures.
Jared M. Pisapia, Martin Rozycki, Hamed Akbari, Spyridon Bakas, Jayesh P. Thawani, Julie S. Moldenhauer, Phillip B. Storm, Deborah M. Zarnow, Christos Davatzikos and Gregory G. Heuer
Fetal ventriculomegaly (FV), or enlarged cerebral ventricles in utero, is defined in fetal studies as an atrial diameter (AD) greater than 10 mm. In postnatal studies, the frontooccipital horn ratio (FOHR) is commonly used as a proxy for ventricle size (VS); however, its role in FV has not been assessed. Using image analysis techniques to quantify VS on fetal MR images, authors of the present study examined correlations between linear measures (AD and FOHR) and VS in patients with FV.
The authors performed a cross-sectional study using fetal MR images to measure AD in the axial plane at the level of the atria of the lateral ventricles and to calculate FOHR as the average of the frontal and occipital horn diameters divided by the biparietal distance. Computer software was used to separately segment and measure the area of the ventricle and the ventricle plus the subarachnoid space in 2 dimensions. Segmentation was performed on axial slices 3 above and 3 below the slice used to measure AD, and measurements for each slice were combined to yield a volume, or 3D VS. The VS was expressed as the absolute number of voxels (non-normalized) and as the number of voxels divided by intracranial size (normalized). A Pearson correlation coefficient was used to measure the strength of the relationships between the linear measures and the size of segmented regions in 2 and 3 dimensions and over various gestational ages (GAs). Differences between correlations were compared using Steiger's z-test.
Fifty FV patients who had undergone fetal MRI between 2008 and 2014 were included in the study. The mean GA was 26.3 ± 5.4 weeks. The mean AD was 18.1 ± 8.3 mm, and the mean FOHR was 0.49 ± 0.11. When using absolute VS, the correlation between AD and 3D VS (r = 0.844, p < 0.0001) was significantly higher than that between FOHR and 3D VS (r = 0.668, p < 0.0001; p = 0.0004, Steiger's z-test). However, when VS was normalized, correlations were not significantly different between AD and 3D VS (r = 0.830, p < 0.0001) or FOHR and 3D VS (r = 0.842, p < 0.0001; p = 0.8, Steiger's z-test). For GAs of 24 weeks or earlier, AD correlated more strongly with normalized 3D VS (r = 0.902, p < 0.0001) than with FOHR (r = 0.674, p < 0.0001; p < 0.0001, Steiger's z-test). After 24 weeks, there was no difference in correlations between linear measures (AD or FOHR) and 3D VS (r > 0.9). Correlations of linear measures with VS in 2 and 3 dimensions were similar, and inclusion of the subarachnoid space did not significantly alter results.
Findings in the study support the use of AD as a measure of VS in fetal studies as it correlates highly with both absolute and relative VS, especially at early GAs, and captures the preferential dilation of the occipital horns in patients with FV. Compared with AD, FOHR similarly correlates with normalized VS and, after a GA of 24 weeks, can be reported in fetal studies to provide continuity with postnatal monitoring.
Jared M. Pisapia, Nikhil R. Nayak, Ryan D. Salinas, Luke Macyszyn, John Y. K. Lee, Timothy H. Lucas, Neil R. Malhotra, H. Isaac Chen and James M. Schuster
As odontoid process fractures become increasingly common in the aging population, a technical understanding of treatment approaches is critical. 3D image guidance can improve the safety of posterior cervical hardware placement, but few studies have explored its utility in anterior approaches. The authors present in a stepwise fashion the technique of odontoid screw placement using the Medtronic O-arm navigation system and describe their initial institutional experience with this surgical approach.
The authors retrospectively reviewed all cases of anterior odontoid screw fixation for Type II fractures at an academic medical center between 2006 and 2015. Patients were identified from a prospectively collected institutional database of patients who had suffered spine trauma. A standardized protocol for navigated odontoid screw placement was generated from the collective experience at the authors' institution. Secondarily, the authors compared collected variables, including presenting symptoms, injury mechanism, surgical complications, blood loss, operative time, radiographically demonstrated nonunion rate, and clinical outcome at most recent follow-up, between navigated and nonnavigated cases.
Ten patients (three female; mean age 61) underwent odontoid screw placement. Most patients presented with neck pain without a neurological deficit after a fall. O-arm navigation was used in 8 patients. An acute neck hematoma and screw retraction, each requiring surgery, occurred in 2 patients in whom navigation was used. Partial vocal cord paralysis occurred after surgery in one patient in whom no navigation was used. There was no difference in blood loss or operative time with or without navigation. One patient from each group had radiographic nonunion. No patient reported a worsening of symptoms at follow-up (mean duration 9 months).
The authors provide a detailed step-by-step guide to the navigated placement of an odontoid screw. Their surgical experience suggests that O-arm–assisted odontoid screw fixation is a viable approach. Future studies will be needed to rigorously compare the accuracy and efficiency of navigated versus nonnavigated odontoid screw placement.