Proposal for evaluating the quality of reports of surgical interventions in the treatment of trigeminal neuralgia: the Surgical Trigeminal Neuralgia Score

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Object

The aim of this study was to design a checklist with a scoring system for reporting on studies of surgical interventions for trigeminal neuralgia (TN) and to validate it by a review of the recent literature.

Methods

A checklist with a scoring system, the Surgical Trigeminal Neuralgia Score (STNS), was devised partially based on the validated STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) criteria and customized for TN after a literature review and then applied to a series of articles. These articles were identified using a prespecified MEDLINE and Embase search covering the period from 2008 to 2010. Of the 584 articles found, 59 were studies of interventional procedures for TN that fulfilled the inclusion criteria and 56 could be obtained in full. The STNS was then applied independently by 3 of the authors.

Results

The maximum STNS came to 30, and was reliable and reproducible when used by the 3 authors who performed the scoring. The range of scores was 6–23.5, with a mean of 14 for all the journals. The impact factor scores of the journals in which the papers were published ranged from 0 to 4.8. Twenty-four of the studies were published in the Journal of Neurosurgery or in Neurosurgery. Studies published in neurosurgical journals ranked higher on the STNS scale than those published in nonneurosurgical journals. There was no statistically significant correlation between STNS and impact factors. Stereotactic radiosurgery (n = 25) and microvascular decompression (n = 15) were the most commonly reported procedures.

The diagnostic criteria were stated in 35% of the studies, and 4 studies reported subtypes of TN. An increasing number of studies (46%) used the recommended Kaplan-Meier methodology for pain survival outcomes. The follow-up period was unclear in 8 studies, and 26 reported follow-ups of more than 5 years. Complications were reported fairly consistently but the temporal course was not always indicated. Direct interview, telephone conversation, and questionnaires were used to measure outcomes. Independent assessment of outcome was only clearly stated in 7 studies. Only 2 studies used the 36-Item Short Form Health Survey to measure quality of life and 4 studies reported on the severity of preoperative pain. The Barrow Neurological Institute pain questionnaire was the most commonly used outcome measure (n = 13), followed by the visual analog scale.

Conclusions

Similar to the STROBE criteria that provide a checklist of items that should be included in reports of observational studies in general, the authors' suggested checklist for the STNS could help editors and reviewers ensure that quality reports are published, and could prove useful for colleagues when reporting their results specifically on the surgical management of TN. It would help the patient and clinicians make a decision about selecting the appropriate neurosurgical procedure.

Abbreviations used in this paper:BNI = Barrow Neurological Institute; BPI = Brief Pain Inventory; GKS = Gamma Knife surgery; IASP = International Association for the Study of Pain; IF = impact factor; MVD = microvascular decompression; QOL = quality of life; RCT = randomized controlled trial; SF-36 = 36-Item Short Form Health Survey; STNS = Surgical Trigeminal Neuralgia Score; STROBE = STrengthening the Reporting of OBservational studies in Epidemiology; TN = trigeminal neuralgia.

Object

The aim of this study was to design a checklist with a scoring system for reporting on studies of surgical interventions for trigeminal neuralgia (TN) and to validate it by a review of the recent literature.

Methods

A checklist with a scoring system, the Surgical Trigeminal Neuralgia Score (STNS), was devised partially based on the validated STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) criteria and customized for TN after a literature review and then applied to a series of articles. These articles were identified using a prespecified MEDLINE and Embase search covering the period from 2008 to 2010. Of the 584 articles found, 59 were studies of interventional procedures for TN that fulfilled the inclusion criteria and 56 could be obtained in full. The STNS was then applied independently by 3 of the authors.

Results

The maximum STNS came to 30, and was reliable and reproducible when used by the 3 authors who performed the scoring. The range of scores was 6–23.5, with a mean of 14 for all the journals. The impact factor scores of the journals in which the papers were published ranged from 0 to 4.8. Twenty-four of the studies were published in the Journal of Neurosurgery or in Neurosurgery. Studies published in neurosurgical journals ranked higher on the STNS scale than those published in nonneurosurgical journals. There was no statistically significant correlation between STNS and impact factors. Stereotactic radiosurgery (n = 25) and microvascular decompression (n = 15) were the most commonly reported procedures.

The diagnostic criteria were stated in 35% of the studies, and 4 studies reported subtypes of TN. An increasing number of studies (46%) used the recommended Kaplan-Meier methodology for pain survival outcomes. The follow-up period was unclear in 8 studies, and 26 reported follow-ups of more than 5 years. Complications were reported fairly consistently but the temporal course was not always indicated. Direct interview, telephone conversation, and questionnaires were used to measure outcomes. Independent assessment of outcome was only clearly stated in 7 studies. Only 2 studies used the 36-Item Short Form Health Survey to measure quality of life and 4 studies reported on the severity of preoperative pain. The Barrow Neurological Institute pain questionnaire was the most commonly used outcome measure (n = 13), followed by the visual analog scale.

Conclusions

Similar to the STROBE criteria that provide a checklist of items that should be included in reports of observational studies in general, the authors' suggested checklist for the STNS could help editors and reviewers ensure that quality reports are published, and could prove useful for colleagues when reporting their results specifically on the surgical management of TN. It would help the patient and clinicians make a decision about selecting the appropriate neurosurgical procedure.

Abbreviations used in this paper:BNI = Barrow Neurological Institute; BPI = Brief Pain Inventory; GKS = Gamma Knife surgery; IASP = International Association for the Study of Pain; IF = impact factor; MVD = microvascular decompression; QOL = quality of life; RCT = randomized controlled trial; SF-36 = 36-Item Short Form Health Survey; STNS = Surgical Trigeminal Neuralgia Score; STROBE = STrengthening the Reporting of OBservational studies in Epidemiology; TN = trigeminal neuralgia.

Trigeminal neuralgia is one of the few chronic neuropathic pain syndromes for which very effective and diverse surgical treatments are available. Recent international guidelines9 and systematic reviews39,46,47 identified the shortage of high-quality evidence that can enable patients, physicians, and health policy makers to select the most effective and efficient surgical treatment. Spatz et al.37 reported that patients found it difficult to choose among surgical treatments for TN for the same reasons. It is essential that high-quality evidence that compares different modalities of treatments is available to provide reliable and balanced selection of a surgical treatment by both patients and health care providers. Wente et al.43 analyzed the contents of leading surgical journals and found that only 3% of articles were reports of RCTs, and of those, 44% compared different surgical procedures and 56% compared medical therapies in surgical patients. Of the neurosurgical RCTs, only 52% were considered to be of good quality.34 Similar trends were found in a Cochrane review on neurosurgical interventions for TN. Of 11 RCTs, only 3 were considered applicable in practice.

Importantly, no studies addressed MVD, the most advocated procedure for treatment of TN.46 Using evidence from nonrandomized interventions requires very carefully designed trials and reporting. A Health Technology Assessment report by Deeks et al.10 provided guidelines for assessment of non-RCTs, which were developed further by Zakrzewska and Lopez47 for reporting surgical outcome in TN. The guidelines task force used these, but stipulated that outcomes needed to be assessed by methods independent of the operator and that this needed to be clearly stated. These guidelines have been used by several authors.4,22,39

Furthermore, Schriger and Altman,35 in their British Medical Journal editorial, suggested that postpublication review of the medical literature was inadequate because letter writing was not considered rewarding, and therefore either the existence or the lack of letters to the editor is not an indicator of “read” status; perhaps many papers remain unread and their results unused. It has been postulated that authors, when challenged about their results (for example when performing systematic reviews), often do not provide sufficient answers,34 and this is a significant error; the British Medical Journal issue of January 2012 highlighted how missing data and incomplete reporting can harm patients.17 Given the difficulty of performing RCTs of widely accepted surgical techniques, it is increasingly important to ensure that surgical reports are written to uniform standards, allowing results to be used in meta-analyses.5 Rughani et al.31 showed clearly how different conclusions can be reached when using national databases when compared with small series on TN.

It is increasingly necessary to ensure that all reports are written using a similar structure so that they can be compared; this led to the Consolidated Standards of Reporting Trials (CONSORT) statement in 1996 for the reporting of RCTs, which has now been accepted by all the major journals.2 However, not all studies are RCTs, and it has been increasingly recognized that these reports also need a more structured format. This then led to the Statement for Reporting Studies of Diagnostic Accuracy (STARD).3 However, this still did not cover all types of studies, and in 2007 a group of epidemiologists, methodologists, statisticians, researchers, and journal editors put forward a proposal for how reporting of observational studies could be improved—this was called the STROBE41 statement (http://www.strobe-statement.org/). This statement is now being increasingly endorsed by both medical and surgical journals, and may be the template that could be used for reporting TN studies.

Aim of Study

The aim of this study was to put forward a checklist and a scoring system in line with the STROBE checklist for quality assessment of papers that report specifically on surgical treatments of TN, to improve the quality of those reports and aid authors and editors.

Methods

MEDLINE and Embase databases were searched for publications reporting surgical therapies for TN in the period between January 2008 and January 2010. The search strategy used was based on one used for a Cochrane systematic review46 and modified according to the criteria provided.

Inclusion Criteria

  1. Papers reporting primary outcome parameter: effect on pain after surgery.
  2. Idiopathic TN.
  3. Prospective and retrospective studies.
  4. Randomized clinical trials.
  5. Language: English.
  6. All gasserian ganglion and posterior fossa procedures.
  7. Redo surgery; that is, separate reports of patients who had 1 prior procedure.

Exclusion Criteria

  1. Technical, anatomical, nontrial experiments, economic, or methodological reports.
  2. Reviews, editorials, surveys, guidelines, or commentaries.
  3. Case reports including < 5 patients.
  4. Non-TN papers.
  5. Symptomatic (secondary) TN or TN with multiple sclerosis.
  6. Peripheral treatments distal to the gasserian ganglion.

Once the papers were identified the titles and abstracts were then read independently by 2 authors (H.A. and J. Z.). If the abstract fulfilled the criteria or there were insufficient data in the abstract, the full papers were obtained and read prior to selection.

A checklist and scoring system, the STNS (Table 1), was devised based on the STROBE statement, the report by Deek et al.,10 previous recommendations from Zakrzewska and Lopez in 2003,47 the TN guidelines committee, and subsequent use of the latter recommendations in other reports.9,39 A range of scores from 0 to 30 was then applied to the papers that fulfilled the inclusion criteria, with scores > 25 being considered high quality. The results were presented at the Society of British Neurological Surgeons' scientific meeting in Leeds in September 2012. Feedback from the discussion was used to refine the scoring system further.

TABLE 1:

The STNS combined with STROBE to design a scoring system*

CriterionScore
Title, Abstract, & Introduction
 abstract provides an informative & balanced summary of what was done & what was found1
Methods section
 presents key elements of study design early in the paper1
 gives TN diagnostic criteria1
 uses International Headache Society or IASP criteria1
 provides a broad description of op technique: e.g., max temp given (RFTC), no. of sites, & dose provided (by GKS)1
 sensory assessment done & any deficits from previous treatments stated1
 FU through interview, telephone, questionnaire (score 0 for notes only)1
 if questionnaire is used, is it provided or reference provided?1
 is it a validated questionnaire?1
 clearly defines all outcomes, exposures, predictors, potential confounders, & effect modifiers1
 describes any efforts to address potential sources of bias, clear statement on use of independent observers1
 describes all statistical methods, including those used to control for confounding1
 explains how missing data were addressed, sample size at the start & at the end, w/ percentage of patients lost to FU stated1
Results section
 gives characteristics of study participants (e.g., demographic, clinical, social)1
 gives characteristics of laterality & divisions of CN V involved1
 details of previous op treatments given1
 summarizes FU time (e.g., average, total amount, range)1
 FU period of ≥12 mos1
 states op findings & failures (MVD)1
 reports nos. of outcome events or summary measures over time, reports outcomes separately for complete & partial pain relief, & defines recurrence1
 were the outcomes reported separately in case of a mixed TN cohort?1
 provides a baseline measure of pain/QOL1
 provides a KM graph1
 the KM graph is correctly constructed1
 provides the exact no. of patients at the end of the KM graph over 3 yrs1
 reports detailed complications related to CN V1
 reports detailed complications outside CN V1
 uses severity & time scales when reporting complications1
 reports immediate op complications1
 reports mortality rate1
total30
additional data suggested by STROBE for Discussion section
 summarize key results w/ reference to study objectives
 discuss limitations of study, taking into account sources of potential bias or imprecision; discuss both direction & magnitude of any potential bias
 give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, & other relevant evidence
 discuss the generalizability (external validity) of the study results
 give the source of funding & the role of the funders in the present study &, if applicable, in the original study on which the present article is based
* CN = cranial nerve; FU = follow-up; KM = Kaplan-Meier; max temp = maximum temperature; RFTC = radiofrequency thermocoagulation.

A randomization software program (RandomAllocations Software version 1.0, M. Saghaei, Department of Anesthesia, Isfahan University of Medical Sciences) was used to randomize the papers to 3 equally distributed groups to be scored by 3 of the authors (H.A., B.M., J.Z.). Ten percent of the scored papers were redistributed among the 3 authors, in such a way that no author reviewed the same paper twice, for validation and consistency of data acquisition. In cases of discrepancy the review was discussed between the authors.

The extracted data and scores were entered directly into a Microsoft Excel spreadsheet generated from a Microsoft Access database. The IFs of all the journals in which reports were found were obtained from the Journal Citation Reports (2010), an annual publication by the Healthcare & Science division of Thomson Reuters. For journals not included in the Journal Citation Reports, an IF of 0 was allocated. The journals were also divided into 2 groups according to the journal's mission statement, readership, and editorial board: 1) mainstream neurosurgical journals; and 2) nonneurosurgical journals.

Statistical Analysis

When examining the correlation of the scores with the IF, the quality scores were noncontinuous categorical data and did not distribute normally. Therefore nonparametric statistical analysis was performed: the Spearman rank correlation test to assess the correlation between the quality scores and IF, and the unpaired t-test for group comparisons. Given the single comparison decided a priori, the significance level was set at p < 0.05.

Results

There were minor discrepancies between authors on some of the scored items. The most significant of these was regarding the reporting on the baseline measure of pain; an agreement was reached to credit only papers that reported the actual baseline measure of pain and not those that just stated that it was measured. This meant that 4 papers instead of 17 were awarded 1 point in this category.12–14,45

Identified Papers

Fifty-nine of 584 papers fulfilled the inclusion criteria. Fifty-six manuscripts were available for review and manuscripts for 3 papers could not be obtained, because those papers were not indexed in the British Library.

The 56 articles were published in a wide range of journals, from principal neurosurgical journals to periodicals that most neurosurgeons would not access regularly. The IF of the journals cited in the Journal Citation Reports ranged from 0.408 to 4.791 (Table 2). The data extracted from the included studies are shown in Table 3.

TABLE 2:

The journals publishing the 56 studies, with 2010 IFs and STNS*

JournalIFAverage Score
mainstream neurosurgery journals w/ published IFs
 Clinical Neurology & Neurosurgery1.6419.00
 World Neurosurgery 20100.6818.00
 Zentralblatt für Neurochirurgie0.9518.00
 Journal of Neurology, Neurosurgery & Psychiatry4.7917.50
 Neurochirurgie0.4116.50
 Neurosurgery3.3016.35
 Neurosurgical Review2.2616.00
 Journal of Neurosurgery2.7415.60
 Canadian Journal of Neurological Sciences1.1815.50
 Journal of the Korean Neurosurgical Society0.6114.50
 British Journal of Neurosurgery0.9714.25
 Acta Neurochirurgica1.3313.67
 Neurosurgical Focus2.3513.00
 Stereotactic & Functional Neurosurgery1.8813.00
 Surgical Neurology1.2612.00
neurosurgery journals w/ no published IFs
 Egyptian Journal of Neurology, Psychiatry and NeurosurgeryNA10.50
 Pan Arab Journal of NeurosurgeryNA10.50
 Progress in Neurological SurgeryNA7.00
 Rawal Medical JournalNA7.00
nonneurosurgery journals
 International Journal of Radiation Oncology Biology and Physics4.5020.25
 Head & Face Medicine1.0416.00
 Neurology India0.8314.50
 Clinical Journal of Pain3.1114.00
 Neurological Sciences1.2213.00
 Cell Biochemistry and Biophysics4.3111.50
 Journal of Neuroimaging1.2910.50
 Technology in Cancer Research and Treatment1.819.00
 Journal of Clinical Neuroscience1.178.50
 Neuroradiology2.876.00
* NA = not applicable.
TABLE 3:

Data extracted from the 56 included studies*

CharacteristicNo. (%)
overall characteristics
 abstract in a structured format52 (93)
 prospective design10 (18)
 retrospective design43 (77)
 study design unclear3 (5)
study population
 presence of basic demographic data49 (87)
 diagnostic criteria clearly stated20 (36)
details of FU method stated
 interview5 (9)
 questionnaire19 (34)
 telephone4 (7)
 interview & questionnaire11 (20)
 various2 (4)
 not stated15 (27)
type of questionnaire used
 BNI scale13 (46)
 other13 (46)
 BNI scale, VAS1 (4)
 BNI, VAS, SF-361 (4)
definitions & outcome measures
 primary outcome measures defined (complete & partial pain relief)32 (57)
 report outcomes separately for complete & partial pain relief30 (54)
 recurrence defined (minor & major)27 (48)
 preop pain levels reported4 (7)
sensory assessment
 not reported27 (50)
 done postop21 (38)
 done preop4 (7)
 done pre- & postop4 (7)
patients treated more than once
 0%2 (4)
 <10%10 (18)
 ≥10%22 (39)
 unclear21 (38)
sample size & length of FU
 sample size at start of FU <30 patients8 (14)
 sample size at start of FU ≥30 patients48 (86)
 FU 1–5 yrs22 (39)
 FU >5 yrs26 (46)
 FU period unclear8 (14)
type of intervention
 SRS25 (45)
 MVD15 (27)
 MVD & SRS3 (5)
 PBC3 (5)
 RFTC3 (5)
 MVD, PGI, RFTC1 (2)
 nerve combing1 (2)
 PBC, MVD1 (2)
 redo MVD1 (2)
 PGI1 (2)
 PBC, PGI1 (2)
 MVD, RFTC, PGI, SRS1 (2)
% of patients lost to FU
 0%19 (34)
 <10%15 (27)
 10–20%5 (9)
 >20%2 (4)
 unclear15 (27)
morbidity & mortality
 mortality rate stated19 (34)
 reports immediate op complications26 (46)
 reports detailed complications of CN V46 (82)
 reports details of complications outside CN V43 (77)
 reports complications in relation to time & severity20 (36)
 uses KM for pain relief outcomes26 (46)
* PBC = percutaneous balloon compression; PGI = percutaneous glycerol injection; SRS = stereotactic radiosurgery; VAS = visual analog scale.† A questionnaire was used in 28 papers (50%).

Study Design

Most studies (77%) were retrospective. There were 3 multicenter studies (5%). A structured abstract with clearly stated objectives was provided in 93% of the studies. Few studies reported on specific parameters that prognosticate outcome—that is, age, operative techniques, type of TN,26,32 and endoscopic identification of neurovascular compression.7 Several papers reported repeat procedures in relatively small numbers of patients,18,28,40,42 whereas others reported them within the context of the whole cohort of patients. In 23 studies patient databases were available, but the means by which the selection of patients was achieved was not stated in most of the studies.

Demographic Data and Diagnostic Criteria

Sample sizes at the start varied from 4012 in the study by Chen et al.6 to 6 in the paper by Ugwuanyi and Kitchen,40 with 86% reporting more than 30 patients. Those reporting the lowest numbers were repeat operations. Most studies provided basic demographic data. In only 20 studies (35%) the diagnostic criteria used were reported, of which 13 (22.8%) used diagnostic criteria from the International Headache Society or the IASP. Only a few studies clearly defined TN according to the Burchiel classification model of Type 1 and Type 211,25,28,32 and analyzed results separately in these groups. Others stated they had mixed groups: 18 (31.5%), but only 12 (66.6%) of those reported the outcomes separately. Diagnostic criteria in 1 series were obtained retrospectively based on a series of 40 binomial questions administered by an independent interviewer to patients up to 10 years post-MVD.26 Only 4 (7%) reported a baseline level of pain12,13,15,45 to which the subsequent postoperative assessments could be made. Statistical methods were provided in 34 studies (59.6%).

Surgical Procedures

The most frequently reported procedures were MVD and GKS, and the largest series reported glycerol and novocaine injections into the gasserian ganglion. Operative procedures were well described in most studies, and the number of isocenters and the treatment dose used for GKS were provided in 30 (96.7%) of 31 and 29 (93.5%) of 31 studies, respectively. Reports on MVD procedures provided details of neurovascular compression in 17 (73.9%) of 23 papers, and only 6 (26.1%) of 23 detailed findings on MRI. Some of the papers reporting on MVD or GKS procedures provided no technical details.

Postoperative Outcomes

Only 22 papers (38.5%) stated the percentage of patients who failed to get any pain relief. Just under half of the studies (26 [45.6%]) provided a Kaplan-Meier analysis, but only 10 (38.4%) of those 26 studies indicated how many patients were still in the study at the end of that analysis. Table 3 shows that outcome measures were not clearly defined. Complications were consistently reported, but very few studies reported them in relation to time after surgery. Sensory deficit following GKS was reported in half of the studies. The mortality rate was not stated in GKS studies, and it was stated in 20 (62.5%) of the 32 non-GKS studies. Some centers have used both questionnaires and interviews as a means of follow-up, but this was not universal. Only 7 studies (12.2%) clearly stated that an independent observer was used to collect outcome data. The most commonly used outcome measure was the BNI scale or some variant of it. The QOL was assessed in 2 studies by using the SF-36.1,27 Azar et al. found no other studies in which the SF-36 was used; they also used the BNI scale in their study to make some comparisons. Two studies used the validated BPI.22,23 There was 1 study comparing the cost analysis of Cyberknife (stereotactic radiosurgery) and MVD.38

The Scores

The maximum STNS that can be achieved is 30; of the selected 56 papers included in this analysis, the scores ranged from 6 to 23.5 (Table 2). One of the two lowest-scoring papers (scoring 6 each) was published in a journal with an IF of 2.87, whereas the other was published in a journal not indexed by Thomson Reuters. The highest-scoring paper, with a score of 23.5, was published in a journal with an IF of 2.739. Our analysis showed that the quality score of the reports and the IF of the journals in which they appeared did not correlate (Spearman rank correlation, ρ = 0.213; 2-sided p = 0.11).

We used the principal neurosurgical journals with published IFs (Table 2), in which the median STNS was 15.6 (interquartile range 12–19) and the mean was 15.52, and compared them with all the other journals grouped together, with a median STNS of 10.5 (range 6–20.25) and a mean of 11.3. The papers reported in the principal neurosurgical journals had a very significantly higher mean STNS when compared with the other journals (unpaired 2-tailed t-test, p = 0.0012). There was no significant difference between the IFs of the principal neurosurgical journals and those of the other journals.

Discussion and Recommendations

To assess the quality of reporting of surgical interventions for TN we devised a checklist and scoring system, the STNS, based on previous publications9,10,39,46,47 and the STROBE statement. The STNS showed that reporting is variable and inconsistent. The scores were higher in reports from neurosurgical journals when compared with other journals. Some studies were published in high-IF journals that we assume were not routinely accessed by neurosurgeons, and the quality of reporting in these was inconsistent. Patient-related outcome measures were poorly reported.

Thus, there is a need to improve the quality of neurosurgical reporting; Kiehna et al.19 have also shown that results of intracranial neurosurgery RCTs in the principal neurosurgical journals are of a lower standard than in major medical journals. It has been shown that standardized checklists for assessing neurosurgical RCTs could be reliably used by reviewers of different experience levels and thus can improve quality. This is important because there is a risk that readers may underestimate or even ignore the role of poor design or reporting when deriving conclusions from reports published in more recognized journals or in journals with a higher IF. It is possible that journals that do not routinely publish reports on TN are less likely to have the relevant expertise, and so may not be as rigorous in the reviewing process. This explains why poorly scored reports were published in high-IF nonneurosurgical journals.

Our study showed that preoperative levels of pain, presence of sensory changes, and impact of the pain on the QOL were not consistently reported. It is essential to measure baseline pain and its impact preoperatively to evaluate outcomes because this is often missing, even in the field of pain medicine.24 Some authors,11,25,26,44 realizing the importance of baseline assessments, attempted to estimate pain preoperatively by interviewing patients postoperatively; in some instances this was done 10 years after the intervention was performed. Another problem when assessing pain outcomes is that TN is episodic, so it is not just the pain intensity that is important but also the frequency and number of branches involved, which led Degn and Brennum11 to suggest a pain vector that takes this into account (http://tn.neurokirurgi.info).

It is now established that a range of outcome measures from different perspectives needs to be used; for example, patient-reported outcomes, independent assessments such as those provided by MRI, and clinical events and therapeutic outcomes such as length of hospitalization, treatment failure, and repeat surgery. The SF-36, the most widely used generic patient-related outcome measure, was used both pre- and postoperatively by Azar et al.1 and Pan et al.27 However, Garratt,16 when commenting on the SF-36, argued that there was an urgent need for “an appropriate and standardised application of measures that include aspects of health and quality of life, and end points that are of genuine importance to patients.” There is ample evidence that outcome measures, if not assessed in an independent, blinded way, are subject to bias and are associated with significantly larger positive treatment effects than blinded outcome assessments.29

Recently the IASP14 put forward suggestions for a variety of outcome scales for patients with chronic pain, some of which are used in TN. Lee et al.20 noted that these requirements have extended the recommended BPI to take into account the impact that TN specifically has on daily living. They have validated its use as a screening tool, but its usefulness for monitoring outcomes over time remains to be established. This is a significant step forward because QOL and impact on daily living are crucial outcome measures, because in some patients pain relief is achieved at the cost of anesthesia dolorosa or loss of hearing; in a musician, for example, this can render the QOL worse than prior to the operation. It is clear that complications and their time course directly influence the QOL, which necessitates a priori risk-balancing before selecting an appropriate surgical procedure.

Questionnaire development and testing is a complex process, as Lee et al.20 have illustrated. Once questionnaires have been tested and shown to be valid, reliable, and reproducible, they cannot be altered by addition or subtraction of items, as has been done by some authors.21,33 Rogers et al.30 devised the BNI scoring system, which combined pain intensity and the use of medication. It was not specified how this scale was to be used, for example, from data in the medical records or from patients' completed forms. This particular scale was used in several studies. Some reported using it prior to surgery and stated that the patients' BNI scores were Grade IV or V,12,15,27,36,45 showing that patients who underwent surgery had intractable pain. Because pain relief after GKS is not immediate, patients remain on medication for several months. Some patients may become reluctant to stop their medication for fear of pain recurrence, and so would provide lower scores on the BNI scale than would be expected. The BNI Facial Numbness Scale was applied by others.8,15 It is a subjective assessment by the patient, which may not always correlate with neurophysiological testing, a more independent assessment.

The STROBE statement emphasizes the need to define all outcome measures and to provide details of the methods of assessment. We would propose the use of the BPI-Facial as the essential outcome measure because it measures not only intensity of pain but also the impact of the disease both on general activities of daily living and other specific activities such as the ability to eat.

When reviewing papers it may be useful to use the guidelines provided by STROBE for the discussion, which are shown in Table 1, but which were not used to generate a score.

Proposal and Conclusions

Our recommendations are as follows. 1) The STNS now needs to be used by authors, journal editors, and reviewers as a checklist when reporting on surgical outcomes in patients with TN. 2) A similar study to ours can be repeated in the future once the STNS is in use to determine whether its widespread use can improve the reporting and hence the generalizability of surgical interventions for TN. Improved generalizability of data could help guide patients, health care professionals, and policy makers in making decisions on the most effective treatments.

Disclosure

Dr. Zakrzewska undertook this work at University College London/University College London Hospitals Trust, and received a portion of funding from the Department of Health's National Institute for Health Research Biomedical Research Centre funding scheme.

Author contributions to the study and manuscript preparation include the following. Conception and design: Akram, Zakrzewska. Acquisition of data: Akram, Mirza, Zakrzewska. Analysis and interpretation of data: Akram, Mirza, Zakrzewska. Drafting the article: all authors. Critically revising the article: Kitchen, Zakrzewska. Reviewed submitted version of manuscript: Kitchen, Zakrzewska. Statistical analysis: Akram, Mirza. Administrative/technical/material support: Akram.

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    • Export Citation
  • 7

    Chen MJZhang WJYang CWu YQZhang ZYWang Y: Endoscopic neurovascular perspective in microvascular decompression of trigeminal neuralgia. J Craniomaxillofac Surg 36:4564612008

    • Search Google Scholar
    • Export Citation
  • 8

    Cheuk AVChin LSPetit JHHerman JMFang HBRegine WF: Gamma knife surgery for trigeminal neuralgia: outcome, imaging, and brainstem correlates. Int J Radiat Oncol Biol Phys 60:5375412004

    • Search Google Scholar
    • Export Citation
  • 9

    Cruccu GGronseth GAlksne JArgoff CBrainin MBurchiel K: AAN-EFNS guidelines on trigeminal neuralgia management. Eur J Neurol 15:101310282008

    • Search Google Scholar
    • Export Citation
  • 10

    Deeks JJDinnes JD'Amico RSowden AJSakarovitch CSong F: Evaluating non-randomised intervention studies. Health Technol Assess 7:iiix11732003

    • Search Google Scholar
    • Export Citation
  • 11

    Degn JBrennum J: Surgical treatment of trigeminal neuralgia. Results from the use of glycerol injection, microvascular decompression, and rhizotomia. Acta Neurochir (Wien) 152:212521322010

    • Search Google Scholar
    • Export Citation
  • 12

    Dellaretti MReyns NTouzet GSarrazin TDubois FLartigau E: Clinical outcomes after Gamma Knife surgery for idiopathic trigeminal neuralgia: review of 76 consecutive cases. J Neurosurg 109:Suppl1731782008

    • Search Google Scholar
    • Export Citation
  • 13

    Dhople AAAdams JRMaggio WWNaqvi SARegine WFKwok Y: Long-term outcomes of Gamma Knife radiosurgery for classic trigeminal neuralgia: implications of treatment and critical review of the literature. Clinical article. J Neurosurg 111:3513582009

    • Search Google Scholar
    • Export Citation
  • 14

    Dworkin RHTurk DCFarrar JTHaythornthwaite JAJensen MPKatz NP: Core outcome measures for chronic pain clinical trials: IMMPACT recommendations. Pain 113:9192005

    • Search Google Scholar
    • Export Citation
  • 15

    Fariselli LMarras CDe Santis MMarchetti MMilanesi IBroggi G: CyberKnife radiosurgery as a first treatment for idiopathic trigeminal neuralgia. Neurosurgery 64:2 SupplA96A1012009

    • Search Google Scholar
    • Export Citation
  • 16

    Garratt A: Patient reported outcome measures in trials. BMJ 338:a25972009

  • 17

    Godlee FWager E: Research misconduct in the UK. BMJ 344:d83572012

  • 18

    Han IShin DChang JKim KChang JHuh R: Effect of various surgical modalities in recurrent or persistent trigeminal neuralgia. Stereotact Funct Neurosurg 88:1561622010

    • Search Google Scholar
    • Export Citation
  • 19

    Kiehna ENStarke RMPouratian NDumont AS: Standards for reporting randomized controlled trials in neurosurgery. A review. J Neurosurg 114:2802852011

    • Search Google Scholar
    • Export Citation
  • 20

    Lee JYChen HIUrban CHojat AChurch EXie SX: Development of and psychometric testing for the Brief Pain Inventory-Facial in patients with facial pain syndromes. Clinical article. J Neurosurg 113:5165232010

    • Search Google Scholar
    • Export Citation
  • 21

    Linskey MERatanatharathorn VPeñagaricano J: A prospective cohort study of microvascular decompression and Gamma Knife surgery in patients with trigeminal neuralgia. J Neurosurg 109:Suppl1601722008

    • Search Google Scholar
    • Export Citation
  • 22

    Little ASShetter AGShetter MEBay CRogers CL: Long-term pain response and quality of life in patients with typical trigeminal neuralgia treated with gamma knife stereotactic radiosurgery. Neurosurgery 63:9159242008

    • Search Google Scholar
    • Export Citation
  • 23

    Little ASShetter AGShetter MEKakarla UKRogers CL: Salvage gamma knife stereotactic radiosurgery for surgically refractory trigeminal neuralgia. Int J Radiat Oncol Biol Phys 74:5225272009

    • Search Google Scholar
    • Export Citation
  • 24

    Loeser JD: Relieving pain in America. Clin J Pain 28:1851862012

  • 25

    Miller JPAcar FBurchiel KJ: Classification of trigeminal neuralgia: clinical, therapeutic, and prognostic implications in a series of 144 patients undergoing microvascular decompression. Clinical article. J Neurosurg 111:123112342009

    • Search Google Scholar
    • Export Citation
  • 26

    Miller JPMagill STAcar FBurchiel KJ: Predictors of long-term success after microvascular decompression for trigeminal neuralgia. Clinical article. J Neurosurg 110:6206262009

    • Search Google Scholar
    • Export Citation
  • 27

    Pan HCSheehan JHuang CFSheu MLYang DYChiu WT: Quality-of-life outcomes after Gamma Knife surgery for trigeminal neuralgia. Clinical article. J Neurosurg 113:Suppl1911982010

    • Search Google Scholar
    • Export Citation
  • 28

    Pollock BEStein KJ: Surgical management of trigeminal neuralgia patients with recurrent or persistent pain despite three or more prior operations. World Neurosurg 73:5235282010

    • Search Google Scholar
    • Export Citation
  • 29

    Poolman RWStruijs PAKrips RSierevelt INMarti RKFarrokhyar F: Reporting of outcomes in orthopaedic randomized trials: does blinding of outcome assessors matter?. J Bone Joint Surg Am 89:5505582007

    • Search Google Scholar
    • Export Citation
  • 30

    Rogers CLShetter AGFiedler JASmith KAHan PPSpeiser BL: Gamma knife radiosurgery for trigeminal neuralgia: the initial experience of The Barrow Neurological Institute. Int J Radiat Oncol Biol Phys 47:101310192000

    • Search Google Scholar
    • Export Citation
  • 31

    Rughani AIDumont TMLin CTTranmer BIHorgan MA: Safety of microvascular decompression for trigeminal neuralgia in the elderly. Clinical article. J Neurosurg 115:2022092011

    • Search Google Scholar
    • Export Citation
  • 32

    Sandell TEide PK: Effect of microvascular decompression in trigeminal neuralgia patients with or without constant pain. Neurosurgery 63:931002008

    • Search Google Scholar
    • Export Citation
  • 33

    Sarsam ZGarcia-Fiñana MNurmikko TJVarma TRKEldridge P: The long-term outcome of microvascular decompression for trigeminal neuralgia. Br J Neurosurg 24:18252010

    • Search Google Scholar
    • Export Citation
  • 34

    Scholler KLicht STonn JCUhl E: Randomized controlled trials in neurosurgery–how good are we?. Acta Neurochir (Wien) 151:5195272009

    • Search Google Scholar
    • Export Citation
  • 35

    Schriger DLAltman DG: Inadequate post-publication review of medical research. BMJ 341:c38032010

  • 36

    Sheehan JPRay DKMonteith SYen CPLesnick JKersh R: Gamma Knife radiosurgery for trigeminal neuralgia: the impact of magnetic resonance imaging-detected vascular impingement of the affected nerve. Clinical article. J Neurosurg 113:53582010

    • Search Google Scholar
    • Export Citation
  • 37

    Spatz ALZakrzewska JMKay EJ: Decision analysis of medical and surgical treatments for trigeminal neuralgia: how patient evaluations of benefits and risks affect the utility of treatment decisions. Pain 131:3023102007

    • Search Google Scholar
    • Export Citation
  • 38

    Tarricone RAguzzi GMusi FFariselli LCasasco A: Cost-effectiveness analysis for trigeminal neuralgia: Cyberknife vs microvascular decompression. Neuropsychiatr Dis Treat 4:6476522008

    • Search Google Scholar
    • Export Citation
  • 39

    Tatli MSatici OKanpolat YSindou M: Various surgical modalities for trigeminal neuralgia: literature study of respective long-term outcomes. Acta Neurochir (Wien) 150:2432552008

    • Search Google Scholar
    • Export Citation
  • 40

    Ugwuanyi UCKitchen ND: The operative findings in re-do microvascular decompression for recurrent trigeminal neuralgia. Br J Neurosurg 24:26302010

    • Search Google Scholar
    • Export Citation
  • 41

    von Elm EAltman DGEgger MPocock SJGøtzsche PCVandenbroucke JP: The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Prev Med 45:2472512007

    • Search Google Scholar
    • Export Citation
  • 42

    Wang LZhao ZWQin HZLi WTZhang HZong JH: Repeat gamma knife radiosurgery for recurrent or refractory trigeminal neuralgia. Neurol India 56:36412008

    • Search Google Scholar
    • Export Citation
  • 43

    Wente MNSeiler CMUhl WBüchler MW: Perspectives of evidence-based surgery. Dig Surg 20:2632692003

  • 44

    Zacest ACMagill STMiller JBurchiel KJ: Preoperative magnetic resonance imaging in Type 2 trigeminal neuralgia. Clinical article. J Neurosurg 113:5115152010

    • Search Google Scholar
    • Export Citation
  • 45

    Zahra HTeh BSPaulino ACYoshor DTrask TBaskin D: Stereotactic radiosurgery for trigeminal neuralgia utilizing the BrainLAB Novalis system. Technol Cancer Res Treat 8:4074122009

    • Search Google Scholar
    • Export Citation
  • 46

    Zakrzewska JMAkram H: Neurosurgical interventions for the treatment of classical trigeminal neuralgia. Cochrane Database Syst Rev 9:CD0073122011

    • Search Google Scholar
    • Export Citation
  • 47

    Zakrzewska JMLopez BC: Quality of reporting in evaluations of surgical treatment of trigeminal neuralgia: recommendations for future reports. Neurosurgery 53:1101222003

    • Search Google Scholar
    • Export Citation

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Article Information

Contributor Notes

Address correspondence to: Harith Akram, F.R.C.S.(Neuro. Surg), Victor Horsley Department of Neurosurgery, The National Hospital for Neurology & Neurosurgery, Queen Square, London WC1N 3BG, United Kingdom. email: harith.akram@doctors.org.uk.Please include this information when citing this paper: DOI: 10.3171/2013.6.FOCUS13213.

© Copyright 1944-2019 American Association of Neurological Surgeons

Headings
References
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    Azar MYahyavi STBitaraf MAGazik FKAllahverdi MShahbazi S: Gamma knife radiosurgery in patients with trigeminal neuralgia: quality of life, outcomes, and complications. Clin Neurol Neurosurg 111:1741782009

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    Begg CCho MEastwood SHorton RMoher DOlkin I: Improving the quality of reporting of randomized controlled trials. The CONSORT statement. JAMA 276:6376391996

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    Bossuyt PMReitsma JBBruns DEGatsonis CAGlasziou PPIrwig LM: The STARD statement for reporting studies of diagnostic accuracy: explanation and elaboration. Croat Med J 44:6396502003

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    Chakravarthi PSGhanta RKattimani V: Microvascular decompression treatment for trigeminal neuralgia. J Craniofac Surg 22:8948982011

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    • Export Citation
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    Chan AW: Out of sight but not out of mind: how to search for unpublished clinical trial evidence. BMJ 344:d80132012

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    Chen LXu MZou Y: Treatment of trigeminal neuralgia with percutaneous glycerol injection into Meckel's cavity: experience in 4012 patients. Cell Biochem Biophys 58:85892010

    • Search Google Scholar
    • Export Citation
  • 7

    Chen MJZhang WJYang CWu YQZhang ZYWang Y: Endoscopic neurovascular perspective in microvascular decompression of trigeminal neuralgia. J Craniomaxillofac Surg 36:4564612008

    • Search Google Scholar
    • Export Citation
  • 8

    Cheuk AVChin LSPetit JHHerman JMFang HBRegine WF: Gamma knife surgery for trigeminal neuralgia: outcome, imaging, and brainstem correlates. Int J Radiat Oncol Biol Phys 60:5375412004

    • Search Google Scholar
    • Export Citation
  • 9

    Cruccu GGronseth GAlksne JArgoff CBrainin MBurchiel K: AAN-EFNS guidelines on trigeminal neuralgia management. Eur J Neurol 15:101310282008

    • Search Google Scholar
    • Export Citation
  • 10

    Deeks JJDinnes JD'Amico RSowden AJSakarovitch CSong F: Evaluating non-randomised intervention studies. Health Technol Assess 7:iiix11732003

    • Search Google Scholar
    • Export Citation
  • 11

    Degn JBrennum J: Surgical treatment of trigeminal neuralgia. Results from the use of glycerol injection, microvascular decompression, and rhizotomia. Acta Neurochir (Wien) 152:212521322010

    • Search Google Scholar
    • Export Citation
  • 12

    Dellaretti MReyns NTouzet GSarrazin TDubois FLartigau E: Clinical outcomes after Gamma Knife surgery for idiopathic trigeminal neuralgia: review of 76 consecutive cases. J Neurosurg 109:Suppl1731782008

    • Search Google Scholar
    • Export Citation
  • 13

    Dhople AAAdams JRMaggio WWNaqvi SARegine WFKwok Y: Long-term outcomes of Gamma Knife radiosurgery for classic trigeminal neuralgia: implications of treatment and critical review of the literature. Clinical article. J Neurosurg 111:3513582009

    • Search Google Scholar
    • Export Citation
  • 14

    Dworkin RHTurk DCFarrar JTHaythornthwaite JAJensen MPKatz NP: Core outcome measures for chronic pain clinical trials: IMMPACT recommendations. Pain 113:9192005

    • Search Google Scholar
    • Export Citation
  • 15

    Fariselli LMarras CDe Santis MMarchetti MMilanesi IBroggi G: CyberKnife radiosurgery as a first treatment for idiopathic trigeminal neuralgia. Neurosurgery 64:2 SupplA96A1012009

    • Search Google Scholar
    • Export Citation
  • 16

    Garratt A: Patient reported outcome measures in trials. BMJ 338:a25972009

  • 17

    Godlee FWager E: Research misconduct in the UK. BMJ 344:d83572012

  • 18

    Han IShin DChang JKim KChang JHuh R: Effect of various surgical modalities in recurrent or persistent trigeminal neuralgia. Stereotact Funct Neurosurg 88:1561622010

    • Search Google Scholar
    • Export Citation
  • 19

    Kiehna ENStarke RMPouratian NDumont AS: Standards for reporting randomized controlled trials in neurosurgery. A review. J Neurosurg 114:2802852011

    • Search Google Scholar
    • Export Citation
  • 20

    Lee JYChen HIUrban CHojat AChurch EXie SX: Development of and psychometric testing for the Brief Pain Inventory-Facial in patients with facial pain syndromes. Clinical article. J Neurosurg 113:5165232010

    • Search Google Scholar
    • Export Citation
  • 21

    Linskey MERatanatharathorn VPeñagaricano J: A prospective cohort study of microvascular decompression and Gamma Knife surgery in patients with trigeminal neuralgia. J Neurosurg 109:Suppl1601722008

    • Search Google Scholar
    • Export Citation
  • 22

    Little ASShetter AGShetter MEBay CRogers CL: Long-term pain response and quality of life in patients with typical trigeminal neuralgia treated with gamma knife stereotactic radiosurgery. Neurosurgery 63:9159242008

    • Search Google Scholar
    • Export Citation
  • 23

    Little ASShetter AGShetter MEKakarla UKRogers CL: Salvage gamma knife stereotactic radiosurgery for surgically refractory trigeminal neuralgia. Int J Radiat Oncol Biol Phys 74:5225272009

    • Search Google Scholar
    • Export Citation
  • 24

    Loeser JD: Relieving pain in America. Clin J Pain 28:1851862012

  • 25

    Miller JPAcar FBurchiel KJ: Classification of trigeminal neuralgia: clinical, therapeutic, and prognostic implications in a series of 144 patients undergoing microvascular decompression. Clinical article. J Neurosurg 111:123112342009

    • Search Google Scholar
    • Export Citation
  • 26

    Miller JPMagill STAcar FBurchiel KJ: Predictors of long-term success after microvascular decompression for trigeminal neuralgia. Clinical article. J Neurosurg 110:6206262009

    • Search Google Scholar
    • Export Citation
  • 27

    Pan HCSheehan JHuang CFSheu MLYang DYChiu WT: Quality-of-life outcomes after Gamma Knife surgery for trigeminal neuralgia. Clinical article. J Neurosurg 113:Suppl1911982010

    • Search Google Scholar
    • Export Citation
  • 28

    Pollock BEStein KJ: Surgical management of trigeminal neuralgia patients with recurrent or persistent pain despite three or more prior operations. World Neurosurg 73:5235282010

    • Search Google Scholar
    • Export Citation
  • 29

    Poolman RWStruijs PAKrips RSierevelt INMarti RKFarrokhyar F: Reporting of outcomes in orthopaedic randomized trials: does blinding of outcome assessors matter?. J Bone Joint Surg Am 89:5505582007

    • Search Google Scholar
    • Export Citation
  • 30

    Rogers CLShetter AGFiedler JASmith KAHan PPSpeiser BL: Gamma knife radiosurgery for trigeminal neuralgia: the initial experience of The Barrow Neurological Institute. Int J Radiat Oncol Biol Phys 47:101310192000

    • Search Google Scholar
    • Export Citation
  • 31

    Rughani AIDumont TMLin CTTranmer BIHorgan MA: Safety of microvascular decompression for trigeminal neuralgia in the elderly. Clinical article. J Neurosurg 115:2022092011

    • Search Google Scholar
    • Export Citation
  • 32

    Sandell TEide PK: Effect of microvascular decompression in trigeminal neuralgia patients with or without constant pain. Neurosurgery 63:931002008

    • Search Google Scholar
    • Export Citation
  • 33

    Sarsam ZGarcia-Fiñana MNurmikko TJVarma TRKEldridge P: The long-term outcome of microvascular decompression for trigeminal neuralgia. Br J Neurosurg 24:18252010

    • Search Google Scholar
    • Export Citation
  • 34

    Scholler KLicht STonn JCUhl E: Randomized controlled trials in neurosurgery–how good are we?. Acta Neurochir (Wien) 151:5195272009

    • Search Google Scholar
    • Export Citation
  • 35

    Schriger DLAltman DG: Inadequate post-publication review of medical research. BMJ 341:c38032010

  • 36

    Sheehan JPRay DKMonteith SYen CPLesnick JKersh R: Gamma Knife radiosurgery for trigeminal neuralgia: the impact of magnetic resonance imaging-detected vascular impingement of the affected nerve. Clinical article. J Neurosurg 113:53582010

    • Search Google Scholar
    • Export Citation
  • 37

    Spatz ALZakrzewska JMKay EJ: Decision analysis of medical and surgical treatments for trigeminal neuralgia: how patient evaluations of benefits and risks affect the utility of treatment decisions. Pain 131:3023102007

    • Search Google Scholar
    • Export Citation
  • 38

    Tarricone RAguzzi GMusi FFariselli LCasasco A: Cost-effectiveness analysis for trigeminal neuralgia: Cyberknife vs microvascular decompression. Neuropsychiatr Dis Treat 4:6476522008

    • Search Google Scholar
    • Export Citation
  • 39

    Tatli MSatici OKanpolat YSindou M: Various surgical modalities for trigeminal neuralgia: literature study of respective long-term outcomes. Acta Neurochir (Wien) 150:2432552008

    • Search Google Scholar
    • Export Citation
  • 40

    Ugwuanyi UCKitchen ND: The operative findings in re-do microvascular decompression for recurrent trigeminal neuralgia. Br J Neurosurg 24:26302010

    • Search Google Scholar
    • Export Citation
  • 41

    von Elm EAltman DGEgger MPocock SJGøtzsche PCVandenbroucke JP: The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. Prev Med 45:2472512007

    • Search Google Scholar
    • Export Citation
  • 42

    Wang LZhao ZWQin HZLi WTZhang HZong JH: Repeat gamma knife radiosurgery for recurrent or refractory trigeminal neuralgia. Neurol India 56:36412008

    • Search Google Scholar
    • Export Citation
  • 43

    Wente MNSeiler CMUhl WBüchler MW: Perspectives of evidence-based surgery. Dig Surg 20:2632692003

  • 44

    Zacest ACMagill STMiller JBurchiel KJ: Preoperative magnetic resonance imaging in Type 2 trigeminal neuralgia. Clinical article. J Neurosurg 113:5115152010

    • Search Google Scholar
    • Export Citation
  • 45

    Zahra HTeh BSPaulino ACYoshor DTrask TBaskin D: Stereotactic radiosurgery for trigeminal neuralgia utilizing the BrainLAB Novalis system. Technol Cancer Res Treat 8:4074122009

    • Search Google Scholar
    • Export Citation
  • 46

    Zakrzewska JMAkram H: Neurosurgical interventions for the treatment of classical trigeminal neuralgia. Cochrane Database Syst Rev 9:CD0073122011

    • Search Google Scholar
    • Export Citation
  • 47

    Zakrzewska JMLopez BC: Quality of reporting in evaluations of surgical treatment of trigeminal neuralgia: recommendations for future reports. Neurosurgery 53:1101222003

    • Search Google Scholar
    • Export Citation
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