Cystic lesion of the ventriculus terminalis: proposal for a new clinical classification

The ventriculus terminalis is a small cavity inside the conus medullaris that is formed during the embryonic development. Previous reports regarding cystic lesion of the ventriculus terminalis (CLVT) in adults have detailed a broad and diversified distribution in terms of clinical symptoms, clinical evolution, neurological findings, and treatment. Therefore, nonstandardized management has led to unsatisfactory outcomes. Thus, the authors propose a new classification system in which the clinical presentation is taken into account to standardize the cases and facilitate the proper management of these lesions. Two more cases are described. The literature was reviewed, dividing the patients into 3 groups by clinical presentation as follows: CLVT Type I, patients with nonspecific neurological symptoms or nonspecific complaints; CLVT Type II, presence of focal neurological deficit; and CLVT Type III, presence of sphincter disturbances (bowel or bladder dysfunction). Two patients were classified as CLVT Type I, 3 as CLVT Type II, and 12 as CLVT Type III. In Type I, no improvement was observed in clinical evaluation after surgery, and stable symptoms were achieved with clinical management. In Type II, 2 patients had total improvement and 1 had subtotal improvement after surgery. Finally, in Type III, 92% of the patients improved postoperatively; among these 33% presented with total improvement. Only 1 case in this group was handled conservatively and no improvement was documented. This new classification is useful to group the patients into 3 clinical types to provide guidance as to the best management options. Treatment for the Type I lesion seems to be best conducted conservatively, whereas Types II and III seem to be best handled surgically.

Surgical outcomes of the endoscopic endonasal transsphenoidal approach for large and giant pituitary adenomas: institutional experience with special attention to approach-related complications

ABSTRACT Objective In this study, we investigate our institutional experience of patients who underwent endoscopic endonasal transsphenoidal approach for treatment of large and giant pituitary adenomas emphasizing the surgical results and approach-related complications. Method The authors reviewed 28 consecutive patients who underwent surgery between March, 2010 and March, 2014. Results The mean preoperative tumor diameter was 4.6 cm. Gross-total resection was achieved in 14.3%, near-total in 10.7%, subtotal in 39.3%, and partial in 35.7%. Nine patients experienced improvement in visual acuity, while one patient worsened. The most common complications were transient diabetes insipidus (53%), new pituitary deficit (35.7%), endonasal adhesions (21.4%), and cerebrospinal fluid leak (17.8%). Surgical mortality was 7.1%. Conclusions Endoscopic endonasal transsphenoidal surgery is a valuable treatment option for large or giant pituitary adenomas, which results in high rates of surgical decompression of cerebrovascular structures.

Malignant peripheral nerve sheath tumor with and without neurofibromatosis type 1

ABSTRACT Objective In this study, we review the institution’s experience in treating malignant peripheral nerve sheath tumors (MPNSTs). A secondary aim was to compare outcomes between MPNSTs with and without neurofibromatosis type 1 (NF1). Methods Ninety-two patients with MPNSTs, over a period of 20 years, were reviewed. A retrospective chart review was performed. The median age was 43.5 years (range, 3–84 years) and 55.4% were female; 41 patients (44.6%) had NF1-associated tumors. Results Mean tumor sizes were 15.8 ± 8.2 cm and 10.8 ± 6.3 cm for patients with and without NF1, respectively. Combined two- and five-year overall survival was 48.5% and 29%. Multivariate analysis confirmed the association of tumor size greater than 10 cm (hazard ratio (HR) 2.99; 95% confidence interval (CI) 1.14–7.85; p = 0.0258) and presence of NF1 (HR 3.41; 95%CI 1.88–6.19; p < 0.001) with a decreased overall survival. Conclusion Tumor size and NF1 status were the most important predictors of overall survival in our population.

Urethral extrusion of a peritoneal catheter in a patient with a neobladder: a rare complication of shunt insertion

The insertion of a ventriculoperitoneal shunt (VPS) is considered the standard of care for several forms of hydrocephalus. Abdominal complications are most common with this procedure, comprising up to 30% of all shunt-related problems. Conversely, visceral perforation or extrusion of the shunt apparatus is rare. Herein we report a rare complication of VPS insertion in which the peritoneal catheter was spontaneously extruded through the urethra of a patient with a neobladder. We further discuss the pathogenesis, diagnosis, and treatment of this condition.

Late obstruction of an endoscopic third ventriculostomy stoma by metastatic seeding of a recurrent medulloblastoma

Endoscopic third ventriculostomy (ETV) has been established as an effective method in the treatment of tumoral obstructive hydrocephalus. Delayed closure of the ETV stoma has been attributed to scarring involving the third ventricular floor. Secondary obstruction of the stoma due to intraventricular tumor seeding is an extremely rare condition, with only one case described to date. The authors report on a unique case of late closure of the ETV stoma caused by metastatic seeding of a recurrent medulloblastoma 9 years after the initial treatment. The patient was submitted to a second endoscopic procedure in which a reddish mass located just at the third ventricular floor was resected, leading to reopening of the previous ETV stoma. To the best of the authors' knowledge, this case is the first report of an ETV obstruction due to metastatic CSF seeding of a medulloblastoma. In such cases of late failure of the ETV stoma because of tumor obstruction, a second ETV can be safely performed and lead to adequate function of the stoma, even if limited by the aggressive nature of the disease.

The role of the trigeminocardiac reflex in postoperative hearing function in non-vestibular schwannoma cerebellopontine angle tumors

The trigeminocardiac reflex (TCR) is a common event during skull base surgery that can lead to intraoperative arterial hypotension and bradycardia. Arterial hypotension associated with TCR can be a negative prognostic factor for postoperative auditory function and ipsilateral tinnitus in patients undergoing surgery for vestibular schwannoma (VS). In this study, the contribution of TCR to postoperative auditory function in non-VS cerebellopontine angle (CPA) tumor surgery was investigated. From a consecutive series of 102 patients with CPA tumors, we studied the occurrence of TCR and its influence on postoperative auditory function in patients with non-VS tumors. Pre- and postoperative auditory function, pre- and intraoperative mean arterial blood pressure, as well as preoperative medication, tumor size, and occurrence of TCR were evaluated. Of the 35 patients evaluated, four developed intraoperative TCR, of whom one was preoperatively deaf. Preoperative functional hearing was detected in 30/35 patients (85.7%): preoperative deafness was documented in one patient in the TCR group and in four patients in the non-TCR group. Of the 30 patients with preoperative functional hearing, 1/3 (33.3%) patients in the TCR group and 23/27 (85.2%) patients in the non-TCR group had functional hearing postoperatively. When patients with large tumors and functional, hearing were considered, only 33.3% of patients in the TCR group and 77.8% of patients in the non-TCR group remained within the same hearing classes following surgical treatment (p=0.1573). TCR may be a negative prognostic factor for postoperative auditory function in patients with large, non-VS CPA tumors.

Transcranial Electrocortical Stimulation to Monitor the Facial Nerve Motor Function During Cerebellopontine Angle Surgery

OBJECTIVE

This study was conducted to investigate the success rate of using the facial motor evoked potential (FMEP) of orbicularis oculi and oris muscles for facial nerve function monitoring with use of a stepwise protocol, and its usefulness in predicting facial nerve outcome during cerebellopontine angle (CPA) surgeries.

METHODS

FMEPs were recorded intraoperatively from 60 patients undergoing CPA surgeries. Transcranial electrocortical stimulation (TES) was performed using corkscrew electrodes positioned at hemispheric montage (C3/C4 and CZ). The contralateral abductor pollicis brevis muscle was used as the control response. Stimulation was always applied contralaterally to the affected side using 1, 3, or 5 rectangular pulses ranging from 200 to 600 V with 50 μs of pulse duration and an interstimulus interval of 2 ms. Facial potentials were recorded from needles placed in the orbicularis oculi and oris muscles.

RESULTS

FMEP from the orbicularis oris and oculi muscles could be reliably monitored in 86.7% and 85% of the patients, respectively. The immediate postoperative facial function correlated significantly with the FMEP ratio in the orbicularis oculi muscle at 80% amplitude ratio (P = .037) and orbicularis oris muscle at 35% ratio (P = .000). FMEP loss was always related to postoperative facial paresis, although in different degrees.

CONCLUSION

FMEPs can be obtained reliably by using TES with 3 to 5 train pulses. Stable intraoperative FMEPs can predict a good postoperative outcome of facial function. However, further refinements of this technique are necessary to minimize artifacts and to make this method more reliable.

Retroclival epidural hematoma in a child affected by whiplash cervical injury: a typical case of a rare condition

Traumatic posterior fossa epidural hematomas are uncommon lesions. Among these lesions, retroclival epidural hematomas (REDH) are particularly rare conditions that usually occur in the pediatric population due to predisposing anatomical features in this patient group. We describe a typical case of traumatic REDH from the mechanism of trauma to outcome. This 8-year-old girl was involved in a motor vehicle accident leading to whiplash cervical injury and cranial nerve palsy. Any children involved in a severe motor vehicle accident with such a sequence of events should raise suspicion for prompt diagnosis.

The parahippocampal gyrus as a multimodal association area in psychosis

Temporal lobe lesions may lead to schizophrenia-like psychosis, a phenomenon resembling psychotic disorders such as schizophrenia. We discuss a patient with a temporo-basal low-grade glioma presenting with bimodal hallucinosis (visual and auditory), a symptom set that is rarely described in psychotic disorders associated with morphological correlates. In light of a literature review of patients experiencing similar bimodal psychotic symptoms and electrophysiological data obtained in non-human primates, we suggest the parahippocampal gyrus to be a multimodal association area with bimodal units.

Prognostic significance of mast cell and microvascular densities in malignant peripheral nerve sheath tumor with and without neurofibromatosis type 1

Malignant peripheral nerve sheath tumors (MPNSTs) are rare and aggressive soft tissue sarcomas with a significant susceptibility to metastasize early in their course. Pathogenesis is yet to be fully elucidated. Recently, the essential role of mast cells in the tumor onset of neurofibromatosis type 1 (NF1)‐associated neurofibromas and MPNSTs was confirmed in both experimental and human studies. In this study, we investigate mast cell density (MCD), microvascular density (MVD), and proliferation index (Ki‐67) in MPNST. A secondary aim was to correlate histological staining to clinical data and survival in patients with and without NF1. In total, 34 formalin‐fixed paraffin‐embedded MPNST tissues from 29 patients were eligible. MCD, MVD, and Ki‐67 labeling index (LI) were analyzed in all stained tissues by a computer‐based quantitative algorithm (Aperio ImageScope). In addition, chart review was performed for clinical data and survival analysis. Overall, MCD, MVD, and Ki‐67 LI were evenly distributed throughout tumor tissue. There was a negative correlation of NF1 status (affected, P = 0.037), tumor size (>10 cm, P = 0.023), and MVD in the tumor periphery (higher tercile, P = 0.002) to survival. Multivariate analysis confirmed the association of MVD in the tumor periphery (higher tercile, P = 0.019) with a decreased overall survival. Diverse mast cell and microvascular distributions suggest that angiogenesis in MPNST occurs independently. The role of mast cells in tumor progression is unclear and lacks prognostic value. Higher MVD has prognostic significance with possible therapeutic implications in MPNST.

The course of Modic vertebral body changes after posterolateral lumbar fusion on fused and adjacent levels: A systematic review of the literature

According to the original description by Modic et al., the natural course of bone marrow signal abnormalities is an inexorable, progressive one, however recent evidence has demonstrated in healthy individuals and those suffering from lumbar disc herniation that the course of endplate degenerative changes is rather dynamic and sometimes regressive. The evolution of such changes in lumbar fused segments and adjacent levels is largely unknown. The literature relevant to the course of Modic changes on fused and adjacent levels, as well as its clinical correspondence in patients undergoing posterolateral lumbar fusion was collected. Two studies met the criteria. Of 38 patients with Modic type I signals preoperatively, 6 regressed to type 0, 22 progressed to type 2, and 10 remained the same postoperatively. Of 12 patients with Modic type 2 signals preoperatively, 2 regressed to type 0 and 10 remained the same postoperatively. None of the articles described the Modic changes in adjacent levels. Clinical and functional outcomes were significantly improved at follow-up regardless of the endplate signal changes. The best available evidence points out to a reduction in Modic type I frequency on fused segments, either regressive or progressive. There was a predominance of new type II changes in postoperative images, which might represent improvement of instability. This study calls into attention the controversial role of Modic changes as an indicator of clinical significance, since clinical and functional outcomes significantly improved regardless of the endplate signal changes.

Spinal metastasis of endometrial stromal sarcoma: clinicopathological features and management

BACKGROUND

Endometrial Stromal Sarcoma (ESS) is a rare uterine malignancy which often metastasizes several years after initial diagnosis. Thoracic spine is a rare ESS metastatic site and its proper management is still not a consensus. We discuss the histopathological features and the management strategies through an illustrative case of a 77 year-old woman with metastasis to the thoracic spine 13 years after total hysterectomy for ESS.

METHODS

Review of the literature and identification of 5 patients, including our present case, with ESS involving the spinal cord. We discuss the outcomes achieved after each therapy. In our case, the patient presented a mass involving the thoracic spinal canal constricting the spinal cord at T7 level. A two-level decompression laminectomy was performed and the lesion was partially excised.

RESULTS

The histopathological along with the immunohistochemical profile mitotic rate indicated the endometrial stromal cells origin of the tumor, confirming the diagnosis of a low-grade ESS metastasis. The patient was managed with surgery in combination with postoperative radiation therapy.

CONCLUSIONS

The small number of published cases precludes definitive conclusions regarding standard management. However, it seems that treatment of metastatic ESS to the spine matches the same general concepts of spine metastasis, namely surgery followed by radiation therapy, due to clinical improvement and long-term disease control of the reported cases. Hormonal therapy may be considered in recurrent disease with strong expression of estrogen and progesterone receptors. However, these findings need confirmation in larger studies.

Predictors of Outcomes and Complications After Microsurgical and Endovascular Treatment of 1300 Intracranial Aneurysms

BACKGROUND

We performed a rigorous statistical analysis of the complications and outcomes of patients with ruptured or unruptured intracranial aneurysms. Our emphasis was on the potential predictive factors when both surgical and endovascular management are offered by a team with balanced microsurgical and endovascular expertise.

METHODS

From January 2005 to December 2011, 1297 consecutive patients presenting with ruptured (n=829) or unruptured (n=468) aneurysms were prospectively enrolled in our vascular database. The treatment modality was determined by consensus of the endovascular and microsurgical teams. The patients' medical and neurological conditions and aneurysm characteristics were compared against the postintervention complication rates and outcomes using multivariate analyses.

RESULTS

The patients mostly underwent clipping for ruptured (63.7%) or unruptured (56.6%) aneurysms. For ruptured aneurysms, higher Hunt and Hess and Fisher grades on admission were key predictors of increased neurological (P < 0.001 and P < 0.001, respectively) and medical (P < 0.001 and P=0.041, respectively) complication rates. No significant differences in the outcomes were observed between the coiling or clipping groups during the follow-up period. For the unruptured group, a family history of intracranial aneurysms was the most relevant predictor for reducing neurological complication rates and increasing survival at 6 months. Hypertension was, however, the strongest factor associated with complications negatively affecting the outcomes.

CONCLUSIONS

For the ruptured and unruptured groups both, the outcomes were generally good, although neurological and medical complications were reasonably more frequent for the ruptured aneurysms. Coiling provided a sustained benefit in lowering the complication rates only in the short term for the unruptured aneurysms. Smoking was associated, paradoxically, with improved outcomes.

Fibular Nerve Repair by Lateral Sural Cutaneous Nerve Graft: Anatomic Feasibility Study and Clinical Results

OBJECTIVE

The common fibular nerve (CFN) is the most frequently injured nerve in the lower limbs. Surgical management is necessary in approximately two thirds of patients and includes neurolysis, suture, graft repair, or nerve transfer. The distal sural nerve is the preferred donor for grafting, but it is not without complications and requires a second incision. We sought to study the surgical anatomy of the lateral sural cutaneous nerve (LSCN) with the aim of repairing CFN injuries through the same incision and as a potential source for grafting in other nerve injuries.

METHODS

The popliteal fossa was dissected in 11 lower limbs of embalmed cadavers to study LSCN variations. Four patients with CFN injuries then underwent surgical repair by LSCN grafting using the same surgical approach.

RESULTS

At the medial margin of the biceps femoris, the LSCN emerged from the CFN approximately 8.15 cm above the fibular head. The LSCN ran longitudinally to the long axis of the popliteal fossa, with an average of 3.2 cm medial to the fibular head. The mean LSCN length and diameter were 9.61 cm and 3.6 mm, respectively. The LSCN could be harvested in all patients for grafting. The mean graft length was 4.4 cm. Motor function was consistently recovered for foot eversion but was recovered to a lesser extent for dorsiflexion and toe extension. All patients recovered sensitive function (75% of S3). Hypoesthesia was recognized at the calf.

CONCLUSIONS

LSCN harvest is a viable alternative for nerve grafting, especially for repairing short CFN injuries, thereby avoiding the need for a second incision.

Endovascular Intervention Versus Surgery in Ruptured Intracranial Aneurysms in Equipoise

Background and Purpose—

The benefits of endovascular intervention over surgery in the treatment of ruptured aneurysms of anterior circulation remains uncertain. Recently, published studies did not find superiority of endovascular intervention, challenging earlier evidence from a clinical trial. The earlier evidence also had a higher than average proportion of patients in good clinical status, leading to uncertainty about external validity of earlier trials.

Methods—

We performed a systematic review of studies after 2005 under a protocol published in the International Prospective Register of Systematic Reviews. Primary outcomes were posttreatment rebleeding and adverse events (procedural complications). Secondary outcomes were dependency at 3 to 6 and 12 months, delayed cerebral ischemia, and seizures.

Results—

Rebleeding was more frequent after endovascular intervention (Peto OR, 2.18 [95% CI, 1.29–3.70]; 3104 participants; 15 studies; I 2 =0%, Grading of Recommendations, Assessment, Development and Evaluation: very low certainty of evidence). Fewer adverse events were reported with the endovascular intervention (RR, 0.71 [95% CI, 0.53–0.95]; 1661 participants; 11 studies; I 2 =14%, Grading of Recommendations, Assessment, Development and Evaluation: low certainty of evidence). Three to six months dependency (RR, 0.82 [95% CI, 0.73–0.93]; 4081 participants; 18 studies; I 2 =15%, Grading of Recommendations, Assessment, Development and Evaluation: low certainty of evidence) and 12-month dependency (RR, 0.76 [95% CI, 0.66–0.86]; 1981 participants; 10 studies; I 2 =0%, Grading of Recommendations, Assessment, Development and Evaluation: low certainty of evidence) were lower after endovascular intervention.

Conclusions—

This study found consistent results between recent studies and the earlier evidence, in that endovascular intervention results in lower chance of dependency compared with surgery for repair of ruptured anterior circulation aneurysms. A lower proportion of patients in good clinical status in this review supports the application of the earlier evidence.

Registration—

URL: https://www.crd.york.ac.uk/PROSPERO . Unique identifier: CRD42018090396.

Retroperitoneoscopic Resection of a Lumbosacral Plexus Schwannoma: Case Report and Literature Review

BACKGROUND AND STUDY AIMS

 Schwannomas are benign tumors derived from the Schwann cells of the peripheral nerve sheath that rarely affect the retroperitoneum. When symptomatic, surgical resection is usually recommended via open surgery or the laparoscopic transperitoneal approach. We discuss the retroperitoneoscopic resection of lumbosacral plexus schwannomas through an illustrative case and literature review. A new management classification is also proposed.

PATIENTS

 A 61-year-old woman affected by schwannomatosis presented with neuropathic pain in her right inguinocrural area for the past 4 years before admission. Preoperative imaging revealed a 2-cm right retroperitoneal tumor lateral to the psoas muscle. The diagnosis of a schwannoma of the ilioinguinal nerve was then suggested. The patient underwent complete tumor resection through retroperitoneoscopy, and no recurrence was observed over the long term. A review of the relevant literature revealed that surgical strategy depends on tumor location, and therefore patients are divided into three groups by tumor position to guide trocar placement: type 1 (paravertebral or over the psoas muscle), type 2 (lateral to the psoas muscle), and type 3 (sacral or pelvic).

RESULTS

 Four patients were classified as type 1, one as type 2, and three as type 3, thereby guiding trocar placement to a lateral, anterior, or inferior montage, respectively.

CONCLUSIONS

 Retroperitoneoscopy is a minimally invasive technique that offers some potential advantages in approaching retroperitoneal masses. This new classification is useful to group patients and thus provide guidance on the best retroperitoneoscopic surgical strategy.

Bilateral mini-open decompression in the treatment of carpal tunnel syndrome caused by persistent median artery: case report

Carpal tunnel syndrome (CTS) is a common peripheral entrapment neuropathy that is caused by increased pressure within the carpal tunnel resulting in a chronic process of median nerve ischemia and segmental demyelination. We report on a patient with bilateral patent persistent median artery (PMA) affected by typical symptomatic CTS who was treated by bilateral mini-open decompression with complete improvement. For PMA-associated CTS, standard decompression is considered the treatment of choice, whereas resection should be reserved for pathological PMA. Mini-open decompression can be an alternative, as we have verified in this first description.

"Million dollar nerve" magnetic resonance neurography: first normal and pathological findings

OBJECTIVES

To evaluate prospectively the feasibility of magnetic resonance neurography (MRN) in identifying the anatomical characteristics of thenar muscular branch (TMB) of the median nerve, also known as the "million dollar nerve," in patients and controls.

METHODS

Thirteen patients affected by carpal tunnel syndrome (CTS) and four healthy controls had their hands scanned on a 3-T MR imaging scanner for TMB visualization. Median nerve anatomical variations were classified into four groups according to Poisel's classification system modified by Lanz. TMB signal intensity and diameter were assessed for the diagnosis of neuropathy.

RESULTS

TMB was successfully identified in all patients and subjects by using MRN. The most suitable pulse sequences to identify and measure nerve diameter were 3D DW-PSIF and T2-FS-TSE. The axial oblique and sagittal oblique planes are complementary in demonstrating its entire course. TMB had mostly an extraligamentous course with radial side origin (93.8%, each). All patients experienced increased T2 signal intensity (p < 0.001) and thickened nerves. Mean TMB diameters were 1.27 ± 0.21 mm (range, 1.02-1.74 mm) and 0.87 ± 0.16 mm (0.73-1.08 mm) (p = 0.008) in the patient and control groups, respectively.

CONCLUSION

MRN is a reliable imaging technique for identification and anatomical characterization of TMB in patients affected by CTS. This innovative imaging workup may therefore be included in the preoperative evaluation of patients scheduled for carpal tunnel release, especially in CTS with TMB involvement or even in isolated TMB neuropathy.

KEY POINTS

• Magnetic resonance neurography allows precise visualization of the thenar muscular branch of the median nerve. • Thenar muscular branch anatomical variations can be correctly identified. • Preoperative scanning can contribute to reducing the risk of iatrogenic injuries during carpal tunnel release, especially in carpal tunnel syndrome with thenar muscular branch involvement or even in isolated thenar muscular branch neuropathy.

Modified simple decompression in the treatment of cubital tunnel syndrome: avoiding ulnar nerve subluxation

Objective

In this study, we propose a modification to the simple decompression technique that contains the ulnar nerve in the cubital fossa, thus preventing subluxation during forearm flexion movements.

Methods

Five consecutive patients with leprosy-associated cubital tunnel syndrome underwent surgery with the modified technique between July 2011 and October 2012.

Results

The most common symptoms were neuropathic pain and sensory changes (both 60%). On the McGowan scale, three patients maintained their preoperative score and two patients improved by two points, while on the Louisiana State University Health Sciences Center scale, two patients maintained the same scores, two improved by two points, and one improved by one point. Four patients were able to discontinue corticosteroid use. The mean follow-up time was 25.6 months (range 2-48 months). There were no recurrences or subluxations in the long-term.

Conclusion

This alternative technique resulted in excellent functional results, as well as successful withdrawal from corticosteroids. Furthermore, it resulted in no ulnar nerve subluxations.